The past, present and future of SETI, the search for extraterrestrial intelligence
About 2,000 years ago, just before the start of the Common Era, the Romans conquered Spain. The Roman Empire was powered by money, and the currency of the time was silver. Fortunately for the Romans, there were an ample number of silver mines in their new Spanish territory.
It takes a lot of energy to smelt silver into coins, so the Romans cut down vast swaths of Spain's forests to burn the wood for fuel. A byproduct of the smelting process is lead, which the Romans used for plumbing. For the first time, our species was engaged in large-scale industrial manufacturing—and also large-scale pollution. Signs of all this can be found in Greenland ice cores.
Pete Worden is the executive director of Breakthrough Initiatives, which funds efforts to search for life beyond Earth. He recently told me Roman silver mining is arguably the first time humans' impact on the planet was noticeable from outer space.
"If you were sitting at a nearby star and had the ability to take a spectrum of the atmosphere, with technology that we can imagine in the next few decades, you would detect these things that are at least, from our understanding, clearly industrial pollutants," he said.
A popular science fiction notion, as portrayed in the novel and movie Contact, by Planetary Society co-founder Carl Sagan, is that intelligent life might pick up our stray TV transmissions. But that's not possible with Earthling-level technology. If aliens in orbit around Proxima Centauri, our nearest stellar neighbor, broadcasted us episodes of I Love Lucy, we wouldn't hear them, unless they put a lot more power in their transmitters than ours.
We are, however, on the verge of being able to pick up missile detection radar-level signals. And if something as noisy as the Arecibo Observatory planetary radar in Puerto Rico, which is used to zap near-Earth asteroids, was aimed in our direction, we'd definitely hear—assuming we were listening and pointing in the right direction.
But in the end, it might not be our radio traffic that gives us away. Intelligent beings might already know we're here, thanks to the way we've tinkered with our planet's ecosystem.
The question of whether or not we are alone in the universe lies at the heart of many reasons we explore space. But for more than half a century, one branch of science has tried to answer the question more directly. SETI, the search for extraterrestrial intelligence, started as a fringe science, surged to a taxpayer-funded endeavor and receded into a privately funded effort.
The field's history involves semi-secret meetings, blustering congressional representatives and unexplained signal detections. Now, a surge of cash has given SETI new life. New arrays of powerful radio telescopes rising in South Africa and Australia could help revolutionize the field. Meanwhile, other upcoming projects promise to realize the dream of watching the entire sky for signals, all of the time.
Is there anybody out there? We may be closer to the answer today than ever before.
When you're finished with the story, don't miss our special episode of Planetary Radio with Breakthrough Initiatives executive director Pete Worden!
The story of modern SETI begins in 1959, when Cornell University scientists Giuseppe Cocconi and Philip Morrison published a paper in Nature titled "Searching for Interstellar Communications." The paper opens with a simple assumption: If intelligent beings know we're here, they might try to get in touch. This premise remains one of the bedrocks of the field.
What sort of beacon would extraterrestrials use? The electromagnetic spectrum is large, ranging from low-frequency radio waves to high-frequency gamma rays. Fortunately, there's a practical limitation that narrows the possibilities: Earth's atmosphere blocks large portions of the spectrum. Cocconi and Morrison reasoned an advanced civilization would recognize our limitations and transmit something we could detect on the ground.
Furthermore, since high-frequency wavelengths require more transmitting power, Cocconi and Morrison believed a good place to search would be in the radio and microwave spectrum, between 1 and 10,000 megahertz. From FM radio to X-band spacecraft communications, this is indeed where we humans do most of our over-the-air communications.
Modern, digitally equipped radio telescopes can listen to large swaths of the spectrum simultaneously. But early on, analog receivers were limited to small slices at a time. To narrow the search further, Cocconi and Morrison turned to the universal language of science. Hydrogen, the lightest and most abundant chemical element in the cosmos, emits photons at frequencies of 1,420 megahertz. Later, a cluster of hydroxyl photon emission frequencies around 1,660 megahertz were proposed. When hydrogen and hydroxyl combine, they form H2O—water. Since life as we know it requires water, the region between these two frequencies became known as the water hole, a proverbial place for galactic citizens to meet in the desert of space. It was a frequent target of early SETI scans, and most modern searches still include it.
The same year Cocconi and Morrison published their landmark paper, Frank Drake, a staff astronomer at the National Radio Astronomy Observatory in Green Bank, West Virginia, independently prepared to conduct the first SETI search using the institution's new 26-meter Tatel radio telescope. The search was dubbed Project Ozma, after a fictional princess from the Land of Oz, and started scanning the water hole for signals from nearby stars Tau Ceti and Epsilon Eridani in 1960.
One year later, the National Academy of Sciences hosted an invitation-only meeting at Green Bank to discuss how to go about conducting further SETI research. The eclectic, interdisciplinary group included Drake, Cocconi, Morrison, the biochemist Melvin Calvin (who won the Nobel Prize in Chemistry during the meeting), Bernard Oliver, who was the vice president of research and development at Hewlett-Packard, the young Carl Sagan, and the scientist John Lilly, who had recently published a controversial book arguing dolphins were an intelligent species.
With a nod to Lilly's book, the participants dubbed themselves "The Order of the Dolphin." One product of the meeting was the Drake equation, which attempts to predict the number of advanced civilizations in the Milky Way able to contact Earth. The equation includes variables such as average star formation rate, the number of habitable planets per star, and the number of planets where intelligent life could evolve.
After 200 hours of observing, Project Ozma came up empty. But the field of SETI was officially born.
For the rest of the 1960s, SETI research remained mostly dormant, aside from a few searches in the Soviet Union. Starting in 1971, two Project Ozma follow-ups named Ozpa and Ozma II used bigger dishes and listened to more stars.
In 1973, another SETI search began, using a radio telescope called Big Ear at Ohio State University. Big Ear was a flat, aluminum dish three football fields wide, with reflectors at both ends.
On the night of August 15, 1977, Big Ear picked up a signal from the constellation Sagittarius that was 30 times stronger than the cosmic background noise, right at the 1,420 megahertz hydrogen line frequency. No one noticed it for a few days, until a volunteer sifting through the previous week's data circled the signal and wrote "Wow!" in the margin.
Jill Tarter is a legendary SETI scientist. She's the Bernard Oliver Chair for SETI at the SETI Institute in Mountain View, California, and is the inspiration for protagonist Ellie Arroway in Contact, played by Jodie Foster in the film adaptation.
Tarter told me Big Ear's automated search program had no built-in logic to stop and focus on the Wow! signal. Furthermore, there was no confirmation system such as a second telescope located elsewhere, which could help determine whether the signal was local to Earth or truly from the stars.
Despite decades of follow-up searches, the Wow! signal was never heard again. To this day, Tarter favors SETI programs that can process data in real time, rapidly follow-up on detections, and rule out local interference.
I asked her if the Wow! signal still haunts the SETI field. "Well, it haunts me," she said.
By the end of the 1970s, NASA got involved, giving the field a huge boost in credibility. The agency planned to conduct SETI research on two fronts. A systematic, all-sky search would be led by NASA's Jet Propulsion Laboratory, primarily using the agency's Deep Space Network facilities. JPL director Bruce Murray, who co-founded The Planetary Society in 1980, was a strong proponent of this approach.
At the same time, NASA's Ames Research Center would examine nearby stars similar to our Sun, using Arecibo, Green Bank, Parkes Observatory in Australia, and Nancay Observatory in France. Both JPL and Ames would look at frequencies between 1,000 and 3,000 megahertz, covering a large swath of the spectrum near the water hole.
But before the search began, it was met with political resistance. In 1979, Senator William Proxmire bestowed his ignominious "Golden Fleece Award" on the program, calling it a waste of taxpayer dollars. Three years later, Proxmire got SETI funding on the chopping block. Carl Sagan personally met with the senator to convince him SETI was a worthwhile endeavor, arguing it would spur development of advanced technologies and potentially offer evidence Earthlings can survive what Sagan dubbed our "technological adolescence," should we make contact with other beings. A petition signed by leading world scientists and Nobel laureates bolstered Sagan's argument.
At the time, the program had strong support from the scientific community, said Andrew Siemion, the director of the SETI Research Center at the University of California, Berkeley.
"Looking back at some of the study conferences that were held, before the first time Congress tried to kill the funding, it's just absolutely incredible," he said. "I mean, it's virtually a who's-who of not just astronomy, but of science and technology."
Proxmire backed down, and following another decade of development, NASA's SETI program officially went online in 1992, innocuously re-branded as the High Resolution Microwave Survey.
NASA contracted much of its SETI activities to the SETI Institute, a nonprofit formed in 1984. A group of SETI researchers, including John Billingham, who spearheaded some of NASA's initial SETI efforts at Ames, grew irked that the academic researchers NASA hired came with high overhead costs, in the form of extra percentages paid to researchers' universities. In the case of Stanford University, Tarter said, the overhead rate was 100 percent—meaning every dollar paid for a researcher's time required another dollar paid to Stanford.
Billingham had an idea: What if an independent institution could hire the researchers directly, charge less, and then apply for the same grants?
"Our whole motive was to save NASA money," said Tarter, who became the SETI Institute's first employee. "We could actually set our own overhead rate at the true cost of doing business. As opposed to 100 percent, it was more like 20 percent." The cost savings were funneled into building hardware for SETI searches.
But the NASA-led search was barely underway when it came under fire again. This time, Nevada Senator Richard Bryan attacked the program. Once more, Sagan and others prepared to lobby on NASA's behalf, but Bryan outright refused to meet with anyone involved with SETI. In 1993, after a total investment of $60 million and just one year of operations, the High Resolution Microwave Survey was canceled.
"This hopefully will be the end of Martian hunting season at the taxpayer's expense," said a press release from Bryan.
The SETI Institute scrambled to pick up the pieces. Fortunately, said Tarter, the proposals for observing time at Arecibo and Parkes had already been peer-reviewed and accepted.
"I then wrote to all of the (observatories) on which we had been granted time and said, 'If we can come up with the money to keep this project going, can we still have the time?' They all responded yes," she said.
The Ames portion of the SETI program rose from the ashes as Project Phoenix, a suite of equipment that could be connected to large radio dishes like Arecibo, Parkes, and Green Bank. From 1995 through 2004, Project Phoenix scanned Sun-like stars at a frequency between 1,000 and 3,000 megahertz.
The JPL all-sky search using NASA's Deep Space Network, however, could not be salvaged. A final attempt to install SETI equipment at NASA's Deep Space Network facility in Goldstone, California, which would passively collect data from wherever the telescope aimed, was swiftly rejected.
"NASA came back and said, 'Oh no you won't.' They really shut it down hard," said Tarter. "Bryan had done this with such vengeance that we became the four-letter-S-word you couldn't say at NASA headquarters."
In 1978, during one of his many appearances on The Tonight Show, Planetary Society co-founder Carl Sagan discussed SETI at length with host Johnny Carson. In a pre-Internet era where most Americans only had a few channels, Sagan and Carson spent 15 minutes on prime-time television discussing everything from Star Wars ("I felt very bad that, at the end, the Wookiee didn't get a medal," Sagan said) to how aliens might send us a signal using prime numbers.
"The remarkable thing is, for all the history of mankind, people have wondered about intelligence elsewhere—I think it's in religion and philosophy, legends—but this is the first time that we have the competence and ability to actually do such a search, and we are just beginning," Sagan said.
The Planetary Society's involvement in SETI practically began when the organization was founded in 1980. Just one year later, NASA and the Society funded Suitcase SETI, a portable spectrum analyzer that could be installed on large radio telescopes like Arecibo. Suitcase SETI eventually grew into Sentinel, an all-sky search using a 26-meter radio telescope at Harvard University. Next came META, the Megachannel ExtraTerrestrial Assay, funded with a significant donation from Steven Spielberg, who was then a Planetary Society board member.
These projects were led by Paul Horowitz, a Harvard physicist and electrical engineer. Horowitz said META was able to pick through 8 million slices of radio frequency at a time, making it the most advanced SETI search ever when it came online in 1985. Yet when compared to modern processing capabilities, its performance was paltry.
"I had that thing (the META computer) in a double rack, and at the top, it said, 'META supercomputer—75 million instructions per second,'" Horowitz said. "Now, your cell phone is better than that."
During a decade of operations, META found 37 "candidate events"—strong signals of unknown origin. None have ever repeated. The Society launched a southern hemisphere clone of the project named META II, and META eventually evolved into BETA, which increased the processing capacity of the Harvard telescope to a quarter-billion channels at once, scanning the water hole between 1,400 and 1,700 megahertz. BETA operated until 1999, when a storm damaged the antenna's drive gear.
Around the same time, Horowitz's group, motivated by Charles Townes, who invented the laser, started tinkering with optical SETI searches. Visible light has a higher frequency than radio waves, allowing more data to be encoded over any given period of time. Like radio waves, visible light also filters through our atmosphere, making it a logical portion of the spectrum for SETI searches.
In 2006, Horowitz and The Planetary Society constructed a 1.8-meter telescope at Harvard which began the first dedicated, all-sky optical SETI survey. The search is still in operation, completing a full survey of the sky visible from Massachusetts every 200 nights.
Meanwhile, in the late 1980s, The Planetary Society, NASA and the National Science Foundation helped fund a west coast SETI effort called SERENDIP at the University of California, Berkeley. SERENDIP, as its name implies, looks for serendipitous SETI detections by piggybacking on traditional astronomical observations made by large radio telescopes. The program has undergone many upgrades and relocations over the years, and was still running at Arecibo when the telescope was damaged by Hurricane Maria in September 2017.
SERENDIP originally processed data in real-time, but Berkeley soon began archiving the data and sifting through them using computer algorithms. There were more data available than could be processed using supercomputers, said Dan Werthimer, who is now chief scientist of the Berkeley SETI Research Center. Werthimer and three other engineers and scientists designed a program to allow home computers to help with the data crunching.
"We had this wild and crazy idea to use volunteers to analyze our data, but we took it around to various people, and nobody seemed to think it would ever work," Werthimer told me. "The Planetary Society said, 'Hey this wild, crazy idea? We want to get behind it.' And they gave us the money to launch the project."
In 1999, Berkeley released the result, SETI@home, and since then more than 8 million people have downloaded the program and donated spare computing power to help search for intelligent life. The open-source software, BOINC, on which SETI@home is based, is now used for other projects. This led to what Werthimer calls "the democratization of supercomputing," where users can choose individual research programs to assist.
Andrew Siemion, the Berkeley SETI Research Center director, credits The Planetary Society's SETI@home involvement for helping keep the field alive prior to his arrival at Berkeley as a student in 2004.
"Science is about standing on the shoulders of giants," he said. "Frankly, we would not be here today were it not for the support specifically of the Planetary Society."
Before the SETI Institute's resurrected NASA program, Project Phoenix, came to a close in 2004, the group planned for what would come next.
A series of workshops involving scientists, engineers and Silicon Valley computing experts concluded the next step in SETI radio research should be a large array of small telescopes. Signals from small dishes can be combined, ultimately covering larger swaths of the sky than single, large dishes, and smaller dishes are cheaper, often using off-the-shelf hardware.
In 2007, the Allen Telescope Array, named after its benefactor, Microsoft co-founder Paul Allen, went online at Hat Creek Observatory in northern California. Using digital technology to process incoming signals, the array was built with long-term scalability in mind. Early on, it collected more data than could be processed. Now, there is a near-match between data volume and processing power, and by the end of the project, SETI scientists should be data-starved.
The original design called for 350 dishes. But the antennas cost more than predicted, and Berkeley, originally a project partner, could not secure hoped-for operating funds from the National Science Foundation. The project was downsized, and taking a page from the Hitchhiker's Guide to the Galaxy, the SETI Institute stopped construction at 42.
"What number are you going to pick if you can't get to 350, right?" said Tarter.
Shortly before 2000, Shelley Wright was working on her physics bachelor's degree at the University of California, Santa Cruz. One day, she saw a flyer for an astrobiology conference at NASA's Ames Research Center, and decided to attend.
During lunch at the conference, she unknowingly sat next to SETI experts Frank Drake and Dan Werthimer. She struck up a conversation, grew interested in the field, and ended up with a gig at Lick Observatory near San Jose, California, where she built an optical SETI detector as part of her undergraduate thesis. Drake became one of her advisors.
Many SETI scientists start in subjects like astronomy, astrophysics or engineering, and either work in related areas or find homes at places like the SETI Institute. Wright is now an assistant professor of physics at the University of California, San Diego, where she designs and builds telescope instruments used to study galaxies and black holes.
She also uses her talents for SETI research. Earlier in her career, she did so quietly, "because it was semi-taboo," she told me.
"The truth is, I think people want to work on SETI," Wright said. "It's just that we all have to pay rent. People need a career path, and if there is no government funding for this, it's really challenging."
Among those who do work on SETI, there are generation gaps corresponding to the field's ups and downs. First came the pioneers, like Drake. A second generation is represented by Tarter, Horowitz and Werthimer. The latest group includes Wright and Siemion, but both are quickly becoming mid-career scientists. A fourth generation needs training.
"There aren't a lot of graduate students that work on it," said Siemion. "This is a huge problem, obviously, for the field to kind of keep it going."
Generational gaps occur in other scientific fields, too, Werthimer said. "But SETI is a little more fragile."
In 2009, NASA launched the Kepler space telescope to hunt for planets around other stars, known as exoplanets. Before Kepler, only a handful of exoplanets were confirmed to exist; that number has now jumped to more than 3,500, with more than 2,000 confirmed by Kepler alone. Another 4,500 await independent confirmation. So far, scientists have found around 30 Earth-sized exoplanets in their stars' habitable zones, where liquid water could exist.
Kepler made the notion of intelligent beings on other worlds far less abstract. A SETI revolution was ready to happen; the field just needed a financial breakthrough.
In 2012, a Russian billionaire named Yuri Milner announced a new annual award called the Breakthrough Prize, designed to hand out cash to scientists making major contributions to fundamental physics.
Milner, who is named after Yuri Gagarin, the first human to fly in space, was born in Moscow and initially studied physics before becoming a successful technology entrepreneur. In its 2017 iteration, the Breakthrough Prize awarded more than $25 million. It is the largest individual monetary science prize, and has expanded to include life sciences and mathematics.
By 2015, Pete Worden, then director of NASA Ames, heard Milner was interested in expanding his philanthropy to bolster the search for life. Under an umbrella group named Breakthrough Initiatives, Milner's benefaction would be split between SETI observations, characterizing nearby exoplanets, and developing a fleet of miniature, laser-powered sail spacecraft to visit the neighboring Alpha Centauri star system.
As a NASA center director, a lot of Worden's day-to-day work focused on "budget and personnel, and, you know, that the toilets don't work in building 18," he told me. He was happiest when he had time to arm himself with snacks, escape his office and visit scientists and engineers working on missions like Kepler.
When Worden found out about Milner's desire to seek answers to fundamental questions about life in the cosmos, he was intrigued. "Probably since I was a teenager—maybe even younger—I've had these questions on my mind," he said. "And they were clearly on Yuri Milner's mind, and he felt that now was the time to begin a set of initiatives to address those questions."
Worden retired from NASA that same year, and became the executive director of Breakthrough Initiatives. "I'm spending most of my time now on these big questions, which is really cool. I can't believe I'm so lucky," he said.
A large cash influx could drastically alter the SETI landscape. The field's two biggest players were the SETI Institute and the SETI Research Center at Berkeley. At the time, representatives from both groups were working together on an initiative called FIRSST, which sought to create a long-term endowment for SETI research.
"If you don't have institutional funding—and apparently we're not going to be able to get that for SETI—then you need something like an endowment, so that people can take risks and do new things that don't necessarily provide publication next month," said Tarter, who was a FIRSST institutional liaison.
Milner ultimately funneled the funding through Berkeley, under a new program called Breakthrough Listen. Breakthrough would use the giant telescopes at Green Bank and Parkes to scan the nearest 1 million stars—a sphere about 1,000 light years across, covering the round-trip distance where other beings may have noticed our 2,000-year-old pollution habits and tried to get in touch. The program would also scan the Milky Way's galactic plane and the nearest 100 galaxies, while another telescope, the Automated Planet Finder at Lick Observatory, would conduct optical SETI searches.
Berkeley engineers set to work upgrading the digital processing capabilities at Green Bank and Parkes. The university's SETI Research Center would process the data, eventually making some of it available for SETI@home users.
Milner allocated $100 million to Breakthrough Listen, to be spent over a 10-year period. Worden said the annual spending rate varies; most recently it was between 6 and 7 million. The FIRSST endowment fizzled, and three SETI Institute representatives, including Tarter, joined the Breakthrough Listen advisory committee. But thus far, no Breakthrough funds have gone to the SETI Institute, or the Allen Array.
"We may just now be finding a way to work gracefully in concert with them," Tarter said. "It's been very disappointing for us, that we were essentially excluded."
For the radio observatories participating in the search, Breakthrough Listen was a welcome new funding source.
In 2013, the National Science Foundation announced it would divest the Green Bank Telescope, forcing the observatory to start funding itself. The process was completed in 2016. In Australia, Parkes faces a similar, uncertain future. Parkes declined to say how much money the observatory has received from Breakthrough Listen thus far, while Green Bank did not respond to interview requests. But the funding was clearly welcome; Breakthrough is now paying to use a quarter of both telescopes' time. In 2015, Karen O'Neil, who is now the director at Green Bank, told The Planetary Society the new money would "go a long way toward helping secure the long-term future of the facility."
Securing observing arrangements at both locations required contracts with the U.S. and Australian governments, but Worden said the process went remarkably smoothly.
"I worked for the government most of my career, and I never saw the government move so quickly," he said. "We signed an agreement within a few weeks for millions of dollars."
Dedicating a quarter of observing time at Green Bank and Parkes to SETI impacts other telescope users. But somewhat making up for that is a reciprocal arrangement between SETI and traditional radio astronomy. The equipment Breakthrough installs can be used by other observers. At both locations, Berkeley engineers spent about a year installing high-end graphical processing units—the same found in video game cards—to process incoming signals. Those processing units are now "the most powerful digital instruments the telescopes have, full stop," said Siemion.
The arrangement also works in reverse. Through a technology called multibeam receivers, Breakthrough plans to use surplus observing bandwidth during other observations to run SETI searches on nearby swaths of sky. And because Breakthrough openly publishes all its data, SETI observations can be used to make other scientific discoveries.
Jimi Green is a senior systems scientist at CSIRO, Australia's national science agency, which runs Parkes Observatory. When I spoke to him via Skype, he sat in an operations center in Sydney, next to an array of screens used to remotely control the telescope. Green said the Breakthrough search is contributing to the quest to understand a mysterious astronomical phenomenon called Fast Radio Bursts, or FRBs.
FRBs are short, high-energy bursts of radio waves believed to come from outside our galaxy. The first was discovered in 2007, by a student searching archival Parkes data for a different reason. Astronomers aren't sure what causes FRBs—they could be anything from colliding black holes to laser-driven sail spacecraft.
"There's a joke in the community that there are more theories for what they are than there are detections," Green said.
Because SETI searches encompass seemingly random locations across the sky, they uniquely contribute to the hunt for FRBs.
"We don't know enough about (FRBs) yet, like where they come from, what mechanisms generate them, and so on," said Green. "So just doing this sort-of blind searching—wherever (Breakthrough) is looking, we're running at the same time—is a great way to do it." In August, the Breakthrough team, working with a collaboration of international researchers, announced they had detected 15 new pulses from a known FRB at a higher frequency and wider bandwidth than ever before.
In April, Breakthrough Listen published the data from 692 stars observed during initial Green Bank telescope observations, and described the results in an upcoming paper for The Astrophysical Journal. Berkeley scientists also published a corresponding list of 11 "significant events" where radio signals spiked above the cosmic background noise. None were believed to be signals from intelligent beings, but 692 is only a fraction of the million stars the project will survey.
Back at Hat Creek Observatory in northern California, the Allen Array continues its own SETI search. Until recently, the array was looking at Kepler exoplanet candidates, but since it is now clear most stars have planets, the array is scanning the nearest 20,000 stars, most of which are red dwarfs. To pay for operating costs, the array allocates half of its observing time to SRI International, which subcontracts telescope usage for various research and communications projects.
Together, Breakthrough and the SETI Institute are conducting the broadest-ever targeted SETI radio search. The telescopes roughly cover frequencies between 1,000 and 15,000 megahertz; NASA's original HRMS program, for comparison, only searched between 1,000 and 3,000 megahertz.
Bill Diamond, the CEO and president of the SETI Institute, said Breakthrough Listen has hardly made the Allen Array redundant. He sees the two efforts as complementary, and notes the Allen Array has its own unique capabilities, including the ability to process data in real time.
"That immediate analysis gives us the opportunity to verify and eliminate false positives," he said.
Tarter said she would still like to find a way to get the array up to 350 dishes, which would increase its sensitivity and allow it to see more of the sky at once.
"I'm not giving up on that one," she said. "That would be one hell of an instrument for both SETI and radio astronomy."
In a 1991 issue of The Planetary Report, Harvard's Paul Horowitz described a discussion he had with SETI pioneer Philip Morrison, and Michael Davis, then director of Arecibo Observatory. At Morrison's house, the trio talked about the future of SETI, theorizing about how to revolutionize the field. Horowitz put forth what he called "a favorite idea," that future radio searches would scrap large, traditional telescopes for massive arrays of small receivers listening to the entire sky all at once.
"There it is," he wrote. "A dry lake bed tiled with glistening purple checkerboards of silicon, quietly receiving radio signals from a multiplicity of directions."
I asked Horowitz if this 26-year-old idea was still feasible. He said it was, but that I shouldn't hold my breath for it to happen anytime soon.
"If someone wanted to put a billion dollars in it, we could probably build such a thing," he said. "It's not harder than getting to the Moon. It's just different."
At Parkes in Australia, Breakthrough Listen is currently surveying the Milky Way's galactic plane. During a single observation, the observatory's 64-meter telescope can listen to an area of sky about three Moons wide at a time. Surveying the galactic plane will take about 1,500 hours, and since Breakthrough only gets about one-fourth of the telescope's observing time, it will take a year to complete the survey. As a result, the telescope can only listen to each slice of sky for five minutes before moving on.
The Planetary Society's 1.8-meter optical SETI telescope at Harvard covers an even smaller area, just slightly larger than the Moon. Though the telescope is allocated entirely to SETI, it still has to fight cloudy Massachusetts nights and takes a year to complete one full sky survey. The total time spent staring at each patch of stars? Forty-eight seconds.
Herein lies the challenge of SETI: If intelligent beings are currently sending us a beacon, it would have to be near-continuous for us to receive it using our current methods.
"If we wanted to do the best possible experiment we could do, we would want to look at every wavelength, every frequency, all the time, in as many ways as we could possibly conceive of," said Andrew Siemion. "For now, we have to have to make choices."
Two new optical SETI projects are hoping to make giant leaps forward in our ability to watch the entire sky, all of the time. At the University of California, San Diego, Shelley Wright leads a team developing a system called PANO-SETI. Wright and other SETI experts, including Horowitz, recently spent a year brainstorming a way to continuously monitor the entire sky at once, which Wright calls "the ultimate optical solution."
A single telescope dish focuses and amplifies the light from one patch of sky at a time, creating sharp, high-resolution images of celestial objects. But using large telescopes for SETI is akin to searching the heavens through a soda straw. To watch the entire sky at once, you could build an array of giant telescopes, but that would be unthinkably expensive, and for optical SETI, you don't really need high-resolution images. Instead, you only need to count the number of photons coming through the telescope and see if that changes.
PANO-SETI relies on Fresnel lenses, named after their French inventor, who originally built them for lighthouses. A Fresnel lens takes a patch of sky and converts it into a single point, and a detector behind the lens called a solid state photomultiplier samples the light every nanosecond, watching for changes that could indicate the presence of a laser signal. The sample rate is faster than any known natural phenomenon, such as pulsars or the twinkling effect created by Earth's atmosphere.
Each hexagonal Fresnel lens is a half-meter across, and Wright's team envisions 126 of them mounted on the outside of an observatory dome just taller than a person. Like a fly's eye, the array would continuously sample the sky as it rotates overhead. Just a few of these 126-lens domes scattered around the world could continually monitor the entire celestial sphere.
PANO-SETI covers the entire visible spectrum, and as a bonus, a little bit of infrared. This is another area of Wright's expertise; in 2015, she commissioned NIROSETI, the first dedicated near-infrared SETI search. It successfully surveyed 1,000 stars, and Wright's team is preparing to publish the results. The idea of infrared SETI has been around for a long time, but it's expensive because the telescope instruments must be cooled to stop radiant heat from interfering with observations, and the detectors have traditionally been difficult to work with. Nevertheless, infrared is a logical place to search for signals; higher-energy visible wavelengths, like blues, scatter easily (this is why our sky is blue), making infrared a compelling choice for would-be extraterrestrial phone calls. (PANO-SETI will not require cooling because it does not dip deep enough into the infrared.)
Right now, Wright's team is testing a single Fresnel lens. They're almost ready to take it out for trial runs, and she also sees potential to use the technology in other fields.
"We're learning a ton of things, which I think are applicable to other applications in astronomy, and other science," she said.
PANO-SETI could detect the most powerful lasers we have on Earth from a distance out to a few thousand light-years. The team has enough funding for design and prototyping, but to make the concept a reality, they'll need additional investment. They pitched the idea to Breakthrough Listen, but have yet to get a response.
Another advantage of all-sky surveys over targeted searches is that they also capture the void of space between stars and galaxies. If there's something unseen saying hello from the blackness, an all-sky search could pick it up.
Eliot Gillum is the director of the SETI Institute's optical SETI program, which recently introduced an all-sky solution called Laser SETI. Goal-wise, Laser SETI is similar to PANO-SETI; the former is less sensitive, but cheaper.
Laser SETI uses off-the-shelf, wide-field camera lenses to monitor the sky. A single observatory has eight cameras, housed in small, horn-shaped enclosures small enough to carry. The concept is relatively inexpensive thanks to advances in computing, 3D printing and electronics, Gillum told me. "You couldn't have done this ten years ago," he said.
Through a device called diffraction grating, Laser SETI splits each point of starlight into threes. As the Earth rotates, the three dots smear across electronic detectors under each lens. The cameras work in pairs to track the points of light in both the horizontal and vertical directions, and the results are fed into a computer that analyzes the trails for brightness changes.
Gillum envisions installing 12 Laser SETI observatories around the world to continually monitor the entire celestial sphere. Each is self-contained, requiring little intervention besides "power and connectivity, and physical security, to make sure somebody doesn't walk away with your very expensive cameras," he said.
In August, the SETI Institute raised more than $100,000 for Laser SETI on the crowdfunding website Indiegogo. Gillum has a working prototype, and said the next step is getting multiple cameras working together. He is in the process of formalizing a partnership with a yet-to-be-disclosed California observatory for testing.
To this day, most SETI searches envision intelligent civilizations intentionally contacting us with radio or laser signals. The I Love Lucy scenario—where we accidentally pick up aliens' weak, wayward transmissions—has never been possible.
That will soon change. A giant network of new radio telescopes coming online will be sensitive enough to pick up "leakage" signals equivalent to those we inadvertently beam away from Earth. The telescopes are being built for traditional astronomical research, but SETI scientists are salivating at the chance to use them to search for intelligent life.
The new network is called the Square Kilometer Array, or SKA, and as its name suggests, it will have a combined collecting area of one square kilometer. Like the Allen Array, the SKA combines the signals from multiple dishes; one proposal for the final design involves 2,000, 15-meter-wide dishes and a million smaller antennas. If it were a single, circular dish, the SKA would be 1.13 kilometers wide, dwarfing any other telescope on Earth. "We really don't want to make single dishes that big," one astronomer told me. "You lose some efficiency (using smaller dishes), but it's worth it."
The SKA is headquartered at Jodrell Bank Observatory in the U.K., with dishes and antennas located in South Africa and Australia. The project, which won't be completed until at least the end of the 2020s, is so large it has precursor projects—and those precursors have their own precursors.
The first phase, SKA1, is currently underway. In Australia, the precursor Murchison Widefield Array (MWA) consists of 2,048 small antennas, laying the groundwork for a system of 130,000 by the time SKA1 is complete. In South Africa, another precursor called MeerKAT will have 64, 13.5-meter-wide dishes, 16 of which are already online. By itself, MeerKAT will be the largest radio telescope in the Southern Hemisphere when finished, and the dishes will be integrated into a total pool of 200 for SKA1.
MeerKAT picks up mid-frequency radio waves, including the part of the spectrum traditionally targeted by SETI searches. As part of its commissioning phase, MeerKAT will conduct sky surveys, mapping the structure of the galaxy while hunting for pulsars and FRBs. Pete Worden said Breakthrough Listen is "deep in discussions" with the MeerKAT team, hoping to run piggyback SETI searches at the same time.
"These are next-generation facilities in terms of their sensitivities, and their field of view, and also in terms of the way that we can access them digitally," said Andrew Siemion. "So it's incredibly easy for us to plug instrumentation into them, and that makes it possible for us to use them for SETI very easily."
MWA is a low-frequency array. Low frequencies are not typically targeted by SETI searches because longer wavelengths constrain how much information can be transmitted over any given period of time.
Low-frequency arrays can, however, cover the entire sky all at once. For this reason, scientists like Dan Werthimer are increasingly interested in conducting SETI searches with arrays like MWA, "not necessarily because we think E.T. might be broadcasting there," but because the experience could be used to build higher-wavelength all-sky arrays like Horowitz envisioned.
"The microwave part of the spectrum that most people think about for SETI experiments—that will be a little harder," said Werthimer.
The second phase of the Square Kilometer Array, SKA-2, includes a mid-frequency array called MFAA. One of its proposed precursors, MANTIS, would use 250,000 antennas to cover 200 square degrees of sky at once—the equivalent of 1,000 Moons. Its frequency range is 450 to 1,450 megahertz—a large chunk of the water hole, making it a good tool for SETI research.
Though the U.S. did not help fund SKA, the National Radio Astronomy Observatory is considering its own ambitious, SKA-like facility called the next-generation Very Large Array, or ngVLA. Should it be built, the ngVLA would consist of 214, 28-meter high-frequency radio dishes in the southwestern U.S. capable of receiving signals from 1,200 megahertz to 116 gigahertz. Jill Tarter said SETI researchers are making the case that the search for life should be part of the ngVLA's science justification, should it be built.
In an era where the term "big data" dominates the technology landscape, many SETI scientists are eyeing improvements to the way telescope signals are stored and processed.
At Parkes, Breakthrough stores up to 100 times more data than a typical telescope user—down to individual voltage levels bouncing off the dish itself. The team currently stores a petabyte, or 1,000 terabytes, of those data. "But they quickly get through that," said Jimi Green, the Parkes scientist.
New algorithms and machine learning could help rule out spurious signals while finding hidden ones scientists don't know to look for. Pete Worden hopes to bring in help, perhaps on a volunteer basis, from unique places like the intelligence community.
"We'd really kind of like to get somebody that may work in the daytime for a three-letter agency, who goes home at night, downloads the data says 'Hey, I found something interesting,'" Worden said.
About a year ago, the SETI Institute teamed up with IBM to start using machine learning to sift through the 54 terabytes of data per day the Allen Array captures. Bill Diamond said IBM was interested in placing the data in "a gymnasium for software" to test new computing algorithms. In return, the SETI Institute gets access to cloud computing resources and tools.
"It's almost like building a new instrument, or building a new telescope," Diamond said.
During his 1978 Tonight Show appearance, Carl Sagan theorized about what it might mean to establish two-way communication with another civilization.
"We are at a very dangerous moment in human history," he said. "We have weapons of mass destruction, we are in the process of inadvertently altering our climate—exhaustion of fossil fuels and minerals—all kinds of problems that come with technology. We are not certain that we will be able to survive this period of what I like to call technological adolescence. Were we to receive a message from somewhere else, it would show that it's possible to survive this kind of period. And that's a useful bit of information to have."
Humans have only had radio technology for a century—just a blip on the galactic timescale. If we do find intelligent beings, it would be "awfully unusual to find them where they just discovered radio a hundred years ago," Werthimer said. Odds are they'll be much more advanced than us, and potentially able to offer the kind of guidance Sagan envisioned.
Hearing nothing won't necessarily mean no one is out there; perhaps we aren't looking the right way. What if intelligent beings communicate using a form of energy stronger than gamma rays? Or chat via subspace, like on Star Trek?
"We have to reserve the right to get smarter," Tarter said. "We may be doing a fantastic, excellent job at just the wrong thing."
Or, we could truly be alone in the cosmos. Paraphrasing Arthur C. Clarke, Siemion said the non-detection of intelligent life would be just as profound as detecting it.
"The only thing weirder than there being intelligent life out there is that there is not intelligent life out there," he said. "These ideas are kind of equally compelling—equally strange and amazing."
At a Breakthrough Initiatives meeting just before the Listen project was announced, each team member predicted the odds the effort would find intelligent life, Worden said.
"The numbers ranged from a percent or two, to ten to the minus fifth," he said. Milner was among the low end of the estimates.
"I was just thinking at the time, if I had gone to the U.S. government and said I want a hundred million bucks to do something, and they asked me what I thought the probability of success was, even if I had said two percent, they would have said, 'you must be nuts,'" he said.
Even negative results help define the boundaries of where and how to look. And the only way to know for sure whether there's anybody out there is to keep searching.
"I think most people in the public think we're always looking, which is totally not true," said Shelley Wright. "We've barely looked, contrary to all of our sci-fi movies."
Quelle: The Planetary Society
Soaring to the depths of our universe, gallant spacecraft roam the cosmos, snapping images of celestial wonders. Some spacecraft have instruments capable of capturing radio emissions. When scientists convert these to sound waves, the results are eerie to hear.
In time for Halloween, we've put together a compilation of elusive "sounds" of howling planets and whistling helium that is sure to make your skin crawl.
Read more about some of the sounds featured here:
Juno Captures the 'Roar' of Jupiter: NASA's Juno spacecraft has crossed the boundary of Jupiter's immense magnetic field. Juno's Waves instrument recorded the encounter with the bow shock over the course of about two hours on June 24, 2016.
Plasma Waves: Plasma waves, like the roaring ocean surf, create a rhythmic cacophony that — with the EMFISIS instrument aboard NASA’s Van Allen Probes — we can hear across space.
Saturn's Radio Emissions: Saturn is a source of intense radio emissions, which were monitored by the Cassini spacecraft. The radio waves are closely related to the auroras near the poles of the planet. These auroras are similar to Earth's northern and southern lights. More of Saturn's eerie-sounding radio emissions.
Sounds of Jupiter: Scientists sometimes translate radio signals into sound to better understand the signals. This approach is called "data sonification". On June 27, 1996, the Galileo spacecraft made the first flyby of Jupiter's largest moon, Ganymede, and this audio track represents data from Galileo's Plasma Wave Experiment instrument.
Sounds of a Comet Encounter: During its Feb. 14, 2011, flyby of comet Tempel 1, an instrument on the protective shield on NASA's Stardust spacecraft was pelted by dust particles and small rocks, as can be heard in this audio track.
October 31-- Orbital ATK Minotaur-C rocket carrying SkySat
An Orbital ATK Minotaur-C rocket is scheduled to six SkySat Earth observation satellites for Planet and several CubeSat payloads., from launch site SLC-576E, at 2:37 p.m.
Nov. 10-- ULA Delta 2 carrying JPSS 1
Dec. 13--Delta 4 carrying NROL-47
A United Launch Alliance Delta 4 rocket is scheduled to launch a classified spacecraft payload for the U.S. National Reconnaissance Office, from launch site SLC-6. Time is to be determined later.
Dec. 22-23-- SpaceX Falcon 9 carrying Iridium Next 31-40
Jan. 30-- SpaceX Falcon 9 carrying Paz
A SpaceX Falcon 9 rocket is scheduled to launch the Paz satellite for Hisdesat of Madrid, Spain, from launch site SLC-4E. Time is to be determined later.
Quelle: Santa Maria Times
In the search for new planets, a lot of the focus has been on finding some that reside in what's called the habitable zone. This is an area between where a planet's orbit receives enough starlight to keep water liquid, but not so much light that it all boils off as steam. Planets in habitable zone orbits are expected to have better prospects of harboring life as we know it from Earth's example.
But it's important to recognize that habitable zone doesn't mean habitable. If a habitable zone's planet's surface reflects enough light, it could end up as a frozen snowball. If its atmosphere has enough greenhouse gases, it could end up a baking hell like Venus.
Now, a team of European researchers has identified something else that could have an immense effect on habitability: the star's magnetic field. Under the right conditions, planets close to a star will experience a strong but variable magnetic field, which can cause induction heating. In the case of one system with several habitable zone planets, the induction heating could be strong enough to convert them into oceans of magma.
Induction heating is a process we sometimes use on Earth. It relies on sweeping magnetic fields across metallic objects. These fields get electrons moving, creating small loops of current, termed "eddy currents." Those currents experience some degree of electrical resistance, which turns the entire metal into a weak resistance heater (think of the red, glowing coils in a portable space heater). With a strong enough magnetic field, the heating can be intense.
The same effect can work in non-metals. Obviously, the amount of current will be smaller, but the resistance the object faces will be larger.
This isn't an issue in our solar system, because planets and moons are mostly far enough from other sources of magnetic fields to experience significant heating (with the possible exception of Jupiter's moon Io, where any induction heating is swamped by gravitational tidal heating). But lots of exosolar systems have planets in close proximity to their host stars, which may have strong magnetic fields.
To get induction heating to work, however, you need a magnetic field that changes relatively rapidly. From a star, this requires a rather particular set of circumstances: the star itself has to rotate rapidly, and its magnetic poles have to be offset a bit from its axis of rotation, just as the Earth's magnetic poles aren't at the geographic poles. With this combination, the star's rotation will sweep its magnetic field across any planets that orbit it.
The European team behind the new report focused on M dwarf stars. Because these are small, relatively cool objects, their habitable zones are close to the star and well within the region where the star's magnetic field is quite strong. They also have magnetic fields that are strong to begin with, sometimes in the area of thousands of Gauss. The magnetic field of our Sun is typically 10 to 1,000 times weaker.
Not all M dwarfs rotate quickly enough for this to matter. Proxima Centauri, which hosts the closest known exoplanet, takes more than 80 days to complete a rotation. But there is a nearby M dwarf that completes a rotation in only three days: TRAPPIST-1, which hosts at least seven planets, three of them in the habitable zone. So, the team decided to model how much of an effect induction heating might have on these bodies.
TRAPPIST-1 has had its magnetic field measured at 600 Gauss, but the authors used an earlier estimate of its rotation period (1.4 days vs. the present estimate of 3.2 days). That probably exaggerates present day heating but may reflect earlier conditions, as stars tend to slow their rotation as they age.
The key unknown, however, is the composition of the planets. The amount of induction heating possible is very sensitive to the materials that are being heated, but at present there's no way of determining what these planets are made of. The team assumed an Earth-like composition, but results could change significantly based on the actual materials that formed the TRAPPIST exoplanets.
In this model, the inner-most planet's orbit, which takes 1.5 days, was a rough match for the star's 1.4-day rotation. As a result, the magnetic fields swept across it relatively slowly, so induction heating wasn't a major factor. At the present estimate of the star's rotation, no planets will end up seeing this benefit. The three outer planets are far enough from the star that they don't see much heating, either. That leaves the three planets in between these groups, one of which resides in the habitable zone, to examine in detail.
Here, induction heating has a somewhat counter-intuitive effect. The star's magnetic fields are at maximal strength at the surface; as you move toward the interior, eddy currents induced in the layers above act as a shield, limiting the strength of the magnetic field. As a result, these planets end up heated from the surface-inward rather than from the core-out like on Earth. The peak heating actually occurs only 10 percent of the way toward the planet's core.
And the heating is rather substantial. For TRAPPIST-1c, the third planet out from the star, induction heating reaches more than 60 percent of the heat released in the planet by radioactive decay. That's enough to melt the entire surface, turning it into a magma ocean in nearly all the different model conditions sampled. The same conditions are likely on TRAPPIST-1d, the one in the habitable zone, where induction heating can be above half the amount of heat released by radioactive decay.
The process, however, may be self-limiting to a degree. Molten minerals tend to be better conductors, which means stronger eddy currents. Although this means more energy released at the surface, it limits the depth to which the magnetic field can penetrate. As a result, the total heating ends up lower, and the prospects for a magma ocean go down a bit. Other conditions, like the cycling of material through plate tectonics, can moderate the effect of induction heating. An active planetary magnetic field would also provide some shielding (the researchers assumed none was present).
In any case, the models make a persuasive case that induction heating will increase volcanic activity on these worlds. And that would have a complicated relationship to habitability. Volcanic activity can cycle up water and carbon dioxide to the planet's surface, restoring an atmosphere if it were lost due to earlier eruptions on the nearby star. That atmosphere, however, would likely create a potent greenhouse effect, making these planets too hot for habitability, given that they're near the inner edge of the habitable zone.
The huge number of assumptions about composition and internal structure required to make this model work mean that it should be viewed as an indication of what could be happening on exosolar systems like this. It's also a general caution; it's easy to get excited about habitable zone planets, but we have a lot of work to do to understand whether they're actually habitable. That work includes fully understanding their stars, atmospheres, and planetary composition. And, unfortunately, there's no technology on the horizon that will get us the planetary composition any time soon.
The universe shouldn't exist, according to new ultra-precise measurements of anti-protons.
But the fact that I'm typing this article and you're reading it, however, suggests that we are here, so something must be awry with our understanding of the physics the universe is governed by.
The universe is the embodiment of an epic battle between matter and antimatter that occurred immediately after the Big Bang, 13.82 billion years ago. Evidently, matter won — because there are galaxies, stars, planets, you, me, hamsters, long walks on sandy beaches and beer — but how matter won is one of the biggest mysteries hanging over physics.
It is predicted that equal amounts of matter and antimatter were produced in the primordial universe (a basic prediction by the Standard Model of physics), but if that's the case, all matter in the universe should have been annihilated when it came into contact with its antimatter counterpart — a Big Bang followed by a big disappointment.
This physics conundrum focuses on the idea that all particles have their antimatter twin with the same quantum numbers, only the exact opposite. Protons have anti-protons, electrons have positrons, neutrinos have anti-neutrinos etc.; a beautiful example of symmetry in the quantum world. But should one of these quantum numbers be very slightly different between matter and antimatter particles, it might explain why matter became the dominant "stuff" of the universe.
So, in an attempt to measure one of the quantum states of particles, physicists of CERN's Baryon–Antibaryon Symmetry Experiment (BASE), located near Geneva, Switzerland, have made the most precise measurement of the anti-proton's magnetic moment. BASE is a complex piece of hardware that can precisely measure the magnetic moments of protons and anti-protons in an attempt to detect an extremely small difference between the two. Should there be a difference, this might explain why matter is more dominant than antimatter.
However, this latest measurement of the magnetic moment of anti-protons has revealed that the magnetic moments of both protons and anti-protons are exactly the same to a record-breaking level of precision. In fact, the anti-proton measurement is even more precise than our measurements of the magnetic moment of a proton — a stunning feat considering how difficult anti-protons are to study.
"It is probably the first time that physicists get a more precise measurement for antimatter than for matter, which demonstrates the extraordinary progress accomplished at CERN's Antiproton Decelerator," said physicist Christian Smorra in a CERN statement. The Antiproton Decelerator is a machine that can capture antiparticles (created from particle collisions that occur at CERN’s Proton Synchrotron) and funnel them to other experiments, like BASE.
Antimatter is very tricky to observe and measure. Should these antiparticles come into contact with particles, they annihilate — you can't simply shove a bunch of anti-protons into a flask and expect them to play nice. So, to prevent antimatter from making contact with matter, physicists have to create magnetic vacuum "traps" that can quarantine anti-protons from touching matter, thereby allowing further study.
A major area of research has been to develop ever more sophisticated magnetic traps; the slightest imperfections in a trap's magnetic field containing the antimatter can allow particles to leak. The more perfect the magnetic field, the less chance there is of leakage and the longer antimatter remains levitating away from matter. Over the years, physicists have achieved longer and longer antimatter containment records.
In this new study, published in the journal Nature on Oct. 18, researchers used a combination of two cryogenically-cooled Penning traps that held anti-protons in place for a record-breaking 405 days. In that time they were able to apply another magnetic field to the antimatter, forcing quantum jumps in the particles’ spin. By doing this, they could measure their magnetic moments to astonishing accuracy.
According to their study, anti-protons have a magnetic moment of −2.792847344142 μN (where μN is the nuclear magneton, a physical constant). The proton's magnetic moment is 2.7928473509 μN, almost exactly the same — the slight difference is well within the experiment's error margin. As a consequence, if there's a difference between the magnetic moment of protons and anti-protons, it must be much smaller than the experiment can currently detect.
These tiny measurements have huge — you could say: universal — implications.
"All of our observations find a complete symmetry between matter and antimatter, which is why the universe should not actually exist," added Smorra. "An asymmetry must exist here somewhere but we simply do not understand where the difference is."
Now the plan is to improve methods of capturing antimatter particles, pushing BASE to even higher precision, to see if there really is an asymmetry in magnetic moment between protons and anti-protons. If there’s not, well, physicists will need to find their asymmetry elsewhere.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
A grassroots movement seeks to build momentum for a second NASA mission to the outer solar system, a generation after a similar effort helped give rise to the first one.
That first mission, of course, was New Horizons, which in July 2015 performed the first-ever flyby of Pluto and is currently cruising toward a January 2019 close encounter with a small object known as 2014 MU69.
New Horizons got its start with letter-writing campaigns in the late 1980s, and the new project hopes to duplicate that success, said campaign co-leader Kelsi Singer, a New Horizons team member who's based at the Southwest Research Institute (SwRI) in Boulder, Colorado.
Nearly three dozen scientists have drafted letters in support of a potential return mission to Pluto or to another destination in the Kuiper Belt, the ring of icy bodies beyond Neptune's orbit, Singer told Space.com.
These letters have been sent to NASA planetary science chief Jim Green, as well as to the chairs of several committees that advise the agency, she added.
"We need the community to realize that people are interested," Singer said. "We need the community to realize that there are important, unmet goals. And we need the community to realize that this should have a spot somewhere in the Decadal Survey."
That would be the Planetary Science Decadal Survey, a report published by the National Academy of Sciences that lays out the nation's top exploration priorities for the coming decade.
"This is the way it normally works," said New Horizons principal investigator Alan Stern, who's also based at SwRI.
"First it bubbles up in the community and then, when there's enough action, the agency starts to get behind it," Stern, who has been the driving force behind New Horizons since the very beginning, told Space.com. "Then it lets the Decadal Survey sort things out."
Stern contributed a letter to the new campaign, and he has voiced support for a dedicated Pluto orbiter. Singer would also be happy if NASA went back to the dwarf planet.
"Pluto just has so much going on," she said.
But there are other exciting options available as well, Singer said. For example, NASA could do a flyby of a different faraway dwarf planet — Eris, perhaps — to get a better idea of the variety and diversity of these intriguing worlds.
Or the agency could target Kuiper Belt objects (KBOs) that have diameters of a few hundred kilometers or so, she added. New Horizons has flown by one "big" KBO (Pluto) and will soon see a small one — 2014 MU69 is just 20 miles (32 km) or so across — but there are no plans at the moment to study anything of an intermediate size up close.
The last Decadal Survey was put out in 2011, and it covers the years 2013 to 2022. The next one is due out in five years, and it will help map out NASA's plans for the 2020s and early 2030s. So Singer knows she and her colleagues must be patient, even if their letter-writing campaign ultimately bears fruit.
"I would say 25 years is the longest I think about," she said, referring to how long it may be before another Kuiper Belt mission gets to its destination. "And I hope it may be more like 15 years."
A massive, glowing bubble of light erupted in the night sky above northeastern Siberia sometime last night (Oct. 26/27), The Siberian Times has reported.
Multiple witnesses reported seeing the bubble, according to the publication, and at least five people captured images of the phenomenon.
While many people quoted by the news site expressed concerns that the phenomenon might have something to do with aliens or "a gap in the space-time continuum," The Siberian Times suspected it was caused by a rocket launch. Now, the Ministry of Defense of the Russian Federation (which operates the Russian armed forces) has said on Facebook that it launched a Topol-M intercontinental ballistic missile last night as part of a test exercise.
The missile was apparently launched from the Plesetsk Cosmodrome in northwestern Russia toward the Kura testing range in Kamchatka, which is on Russia's western, Pacific peninsula, according to The Siberian Times and the Russian Ministry of Defense.
The Siberian Times also reports that the northern lights were expected to be particularly bright last night, which explains why some of the photographers were already watching the sky when the bubble appeared.
Fears from locals of 'aliens arriving', but there is a surprising explanation and, yes, there was an unusual object in the sky.
'But gradually the ball began to expand, it became clear that this is not some radiance ... and it became scary ...' Picture: Alexey Yakovlev
The illuminated ball looming over the forest was seen clearly in the town of Salekhard right on the Arctic Circle, but was also visible over a swathe of northern Siberia in the night sky.
Residents from Yamalo-Nenets region reported 'shivers down their spines' and the social media went alive with claims of aliens arriving in an awesome UFO.
The glowing ball rose from behind the trees and moved in my direction.' Pictures: Sergey Anisimov
The extraordinary sight was captured by leading Siberian photographer Sergey Anisimov who admitted: 'At first I was taken aback for a few minutes, not understanding what was happening.
'The glowing ball rose from behind the trees and moved in my direction.
'My first thought was about the most powerful searchlight, but the speed of changing everything around changed the idea of what was happening.
'This is such a vision!' Pictures: Alexey Yakovlev
'The ball began to turn into an arc and gradually dissipated.'
After the multi-coloured light show was over he went home.
'Kids (5-6 years old) walking in the yard emotionally began to tell me about an unusual phenomenon, using the words 'aliens', 'the portal to another dimension' and the like....'
This was the launch of a Topol-M intercontinental ballistic missile from Plesetsk cosmodrome aimed at the Kura testing range in Kamchatka on the country's Pacific coast. Picture: The Siberian Times
Another photographer Alexey Yakovlev spotted the spectacle at Strezhevoi, in the north of Tomsk region, some 840 kilometres away.
'And at first I thought - it is such a radiance of such an unusual form - round in shape.
'But gradually the ball began to expand, it became clear that this is not some radiance ... and it became scary ...
'It's a gap in the space-time continuum.'
'It's good that I was not alone... they made it clear that the group of people cannot hallucinate.'
'This is such a vision!'
Anastasia Boldyreva posted simply: 'Aliens arrived.'
Vasily Zubkov said: 'I went out to smoke a cigarette and thought it was the end of the world.'
'I went out to smoke a cigarette and thought it was the end of the world.' Pictures: Vkontakte
Another local Nurgazy Taabaldiev said: 'It's a gap in the space-time continuum.'
In fact the reason photographers were out watching the sky was an amazing show of northern lights - or Aurora Borealis - but there was an extra dimension too.
This was the launch of a Topol-M intercontinental ballistic missile from Plesetsk cosmodrome aimed at the Kura testing range in Kamchatka on the country's Pacific coast.
The launch was one of several last night in exercises by the Russian strategic nuclear forces, as confirmed by the Russian defence ministry.
It was the the trace of the Topol rocket - capable of carrying nuclear missiles - that caused this extraordinary phenomenon in the sky.
As photographer Yakovlev posted accurately: 'It seems I accidentally shoot the launch of a secret space rocket from Plesetsk'.
Quelle: The Siberian Times
Three different varieties of plants growing in the Veggie plant growth chamber on the International Space Station were harvested this morning. Photo credit: NASA/ISS
Early Friday morning, astronauts onboard the International Space Station were busy at work, harvesting three varieties of leafy greens from the Veggie growth chamber and installing the next generation of plant research – the high-tech Advanced Plant Habitat.
Simultaneously Growing Three Plant Varieties a First for Veggie
The Veggie plant growth team kicked it up a notch with their sixth round of crops grown aboard the International Space Station with experiment VEG-03D. For the first time, three different plant varieties are simultaneously growing in the Veggie chamber.
On Oct. 27, station astronaut Joe Acaba harvested Mizuna mustard, Waldmann’s green lettuce and Outredgeous Red Romaine lettuce, providing himself and his crew with the makings of a salad — once they top it with salad dressing sent up by the ground crew at Kennedy Space Center in Florida, of course.
“It's an impressive harvest. Joe did a great job!" said Veggie project manager Nicole Dufour.
“As a continuation of our Veg-03 tech demo efforts, we wanted to try something a little bit different. Building on some of our current ground testing, we decided to attempt a mixed crop. We were hoping that the visual diversity of the plants would be more enjoyable to the crew, as well as the variety of flavors offered by the different types of leafy greens.”
During the harvest, Acaba only clipped about half of the leafy greens, leaving the rest to continue growing for a future yield. This technique, called cut-and-come-again repetitive harvesting, allows the crew to have access to fresh produce for a longer period of time.
Growing three different crops at the same time wasn't without its challenges.
“The biggest complication we have faced thus far has been how well the Mizuna has been growing," Dufour said. "Its long, spear-like stalks tend to get caught in the bellows as the crew opens and closes the unit to water the plants.”
After the Veggie harvest, the crew kept on their virtual overalls and went on to install the Advanced Plant Habitat (APH), NASA’s largest plant growth chamber.
Advanced Plant Habitat Turns On, Turns Up Research
As Acaba switched gears from Veggie to the new plant habitat around 5:45 a.m. EDT Friday, APH project manager Bryan Onate and his team walked Acaba through procedures to install the plant habitat into an Expedite the Processing of Experiments to Space Station, or EXPRESS, rack in the Japanese Experiment Module Kibo.
"It's amazing that a plant growth system that began from a blank sheet of paper about five years ago now is installed on the space station," Onate said. "Plant scientists are really going to be able to learn utilizing this system."
The plant habitat is a fully enclosed, closed-loop system with an environmentally controlled growth chamber. It uses red, blue and green LED lights, and broad spectrum white LED lights. The system's more than 180 sensors will relay real-time information, including temperature, oxygen content and moisture levels back to the team at Kennedy.
"APH will be the largest plant growth system on the space station," Howard Levine, the chief scientist in Kennedy's Utilization and Life Science Office who started working on APH seven years ago, said. "It will be capable of hosting multigenerational studies with environmental variables tracked and controlled in support of whole plant physiological testing and bioregenerative life support system investigations."
Once the team at Marshall completes an EXPRESS rack water flow test, the Kennedy team will power up the system. After the water cooling system with the APH passes the test, functional checkout of the plant habitat will begin and take about one week to complete.
Four power feeds to the plant habitat will be turned on and the Kennedy team will monitor the system's Plant Habitat Avionics Real-Time Manager, or PHARMER, for a response. This unique system provides real-time telemetry, remote commanding and photo downlink to the team at Kennedy.
After the PHARMER has verified all subsystems are a go, space station crew members will install the science carrier and initiate the growth of test crops - Arabidopsis seeds, small flowering plants related to cabbage and mustard, and dwarf wheat - during an overlapping timetable of about five weeks. During this time, the system will be monitored for its capability to grow plants, capture and reuse water, and maintain the atmosphere in the growth chamber.
"The test will help us to determine if the planting procedure is good and the habitat is operating as designed," Onate said. "The results of plant growth in the habitat will be compared with the results of tests completed in the control unit here at Kennedy."
All of these preparations are leading up to the initiation of PH-01, which will grow five different types of Arabidopsis and is scheduled to launch on Orbital ATK's ninth commercial resupply mission to the space station.
The nutritional boost of fresh food and the psychological benefits of growing plants become paramount as the agency plans for future missions to deep space destinations.
Researchers based millions of kilometres from Mars have unveiled new evidence for how contemporary features are formed on the Red Planet. Their innovative lab-based experiments on carbon dioxide (CO2) sublimation - the process by which a substance changes from a solid to a gas without an intermediate liquid phase - suggest the same process is responsible for altering the appearance of sand dunes on Mars.
The research was led by a Trinity College Dublin team comprising PhD candidate in the School of Natural Sciences, Lauren Mc Keown, and Dr Mary Bourke, along with Professor Jim McElwaine of Durham University. Their work, which describes phenomena unlike anything seen on Earth, has just been published in the Nature journal Scientific Reports.
Linear gullies on a dune in Matara Crater, Mars, Red and white arrows point to pits.
Lauren Mc Keown said: "We've all heard the exciting news snippets about the evidence for water on Mars. However, the current Martian climate does not frequently support water in its liquid state -- so it is important that we understand the role of other volatiles that are likely modifying Mars today."
"Mars' atmosphere is composed of over 95% CO2, yet we know little about how it interacts with the surface of the planet. Mars has seasons, just like Earth, which means that in winter, a lot of the CO2 in the atmosphere changes state from a gas to a solid and is deposited onto the surface in that form. The process is then reversed in the spring, as the ice sublimates, and this seasonal interplay may be a really important geomorphic process."
Dr Bourke added: "Several years ago I discovered unique markings on the surface of Martian sand dunes. I called them Sand Furrows as they were elongated shallow, networked features that formed and disappeared seasonally on Martian dunes. What was unusual about them was that they appeared to trend both up and down the dune slopes, which ruled out liquid water as the cause."
"At that time I proposed that they had been formed by cryo-venting -- a process whereby pressurised CO2 gas beneath the seasonal ice deposit erodes complex patterns on the dune surface when the ice fractures and releases the gas in towering dust and gas geysers. I was delighted when Lauren joined the Earth and Planetary Surface Process Group in the Department of Geography to work on this phenomenon with Jim and myself. What was required was a demonstration of how sand would respond to sublimation of CO2 ice, and this published work is an important step in providing that required proof."
The researchers designed and built a low humidity chamber and placed CO2 blocks on the granular surface. The experiments revealed that sublimating CO2 can form a range of furrow morphologies that are similar to those observed on Mars.
Linear gullies are another example of active Martian features not found on Earth. They are long, sometimes sinuous, narrow carvings thought to form by CO2 ice blocks which fall from dune brinks and 'glide' downslope.
Lauren Mc Keown said: "The difference in temperature between the sandy surface and the CO2 block will generate a vapor layer beneath the block, allowing it to levitate and maneuver downslope, in a similar manner to how pucks glide on an ice-hockey table, carving a channel in its wake. At the terminus, the block will sublimate and erode a pit. It will then disappear without a trace other than the roughly circular depression beneath it."
"While gullies on Earth are commonly formed by liquid water, they almost always terminate in debris aprons and not pits. The presence of pits therefore provides more support for a hypothesis whereby CO2 blocks are responsible for linear gullies."
By sliding dry ice blocks onto the sand bed in the low humidity chamber, the group showed that stationary blocks could erode negative topography in the form of pits and deposit lateral levees. In some cases, blocks sublimated so rapidly that they burrowed beneath the subsurface and were swallowed up by the sand in under 60 seconds.
Professor McElwaine said: "This process is really unlike anything seen to occur naturally on Earth - the bed appears fluidised and sand is kicked up in every direction. When we first observed this particular effect, it was a really exciting moment."
By generating 3-D models of the modified bed in each case, pit dimensions could be used to predict the range of block sizes that would erode the pits seen on Mars, which vary in diameter from 1 m to up to 19 m. A pit on Russell Crater megadune on Mars was observed to grow within one Mars Year to an extent predicted by these calculations, following the observation of a block within it the previous year.
The next phase of work, supported by Europlanet Horizon 2020 funding, will see the team head to the Open University Mars Chamber to assess the influence of Martian atmospheric conditions on these new geomorphic processes and test a numerical model developed by Professor McElwaine.
Wenn Kleinflugzeuge bei Tage und bei Nacht für Unruhe sorgen, gibt es auch bei unserer UFO-Meldestelle Anrufe und E-Mails welche Nachfragen beinhalten, WER da die Ruhe stört oder am Himmel blinkt.
So bekamen wir aus dem Raum Parkstein im September die Anfrage, wieweit wir auch für Fluglärm der nicht einzuordnen zuständig wären...
So erregte sich Herr K. am Telefon, das schon die örtliche Presse sich darum bemühe, aber scheinbar auch nicht herausfinden könne, woher und warum der Lärm über Stunden zu hören wäre. Ein kurzes Handy-Video auf welchem ein Himmelsausschnitt ohne jeglichen Flugkörper zu sehen ist schickte er uns zu und so kann man auf der Aufnahme ein Brummen hören, welches sich sehr nach Kleinflugzeug anhörte.
Nun brachte die örtliche Presse ihre Nachforschungen um den Fluglärm an die Öffentlichkeit und irgendwie "will es keiner gewesen sein":
Diese Flugspuren wurden am Donnerstag, 28. September, um 14.05 Uhr über Parkstein aufgezeichnet. Die Pilatus PC-12 war teilweise nur 250 Meter über dem Basaltkegel und zog während des dreistündigen Fluges auch Kreise über Trabitz und Neustadt am Kulm. Bild: Trott
Ein Motorflieger dreht Runden um den Parksteiner Basaltkegel. Zwei Tage in Folge. Immer und immer wieder. Die Bürger sind genervt und wollen sich beschweren. Aber wo? Wer ist zuständig? Und wer fliegt da eigentlich? Fragen, die nicht ganz so einfach zu beantworten sind. Und schnell erst recht nicht.
(pdtr) 28. September, früher Nachmittag. Ein Parksteiner ruft in der Redaktion an. "Hören Sie mal!" Es brummt im Hintergrund. Ein Flugzeug. Schon wieder. So gehe das seit einer geschlagenen halben Stunde, erzählt der Anrufer. Und auch schon am Vortag habe der Motorflieger ständig seine Runden über der Siedlung gedreht. Der Bürger will im Garten seine Ruhe haben. Was sei da eigentlich los? Eine militärische Übung vielleicht? "Wir fragen mal nach", verspricht der Kollege. Wenn es nur so einfach wäre.
Um eine Übung der Bundeswehr auszuschließen, rufen wir zunächst in der Ostmark-Kaserne an. Standortfeldwebel Michael Koller weiß nichts von einer Übung. Er schlägt eine Nachfrage beim Presseoffizier des Artilleriebataillons oder der US-Streitkräfte vor. Dort ist jetzt, am späten Freitagnachmittag, schwer ein Ansprechpartner zu finden. Weil der Militärflughafen als Abflughafen der Maschine in Frage kommt, fragen wir bei "Public Affairs" der US-Armee in Grafenwöhr nach. Oder haben es zumindest vor.
Wochenende, Brückentag und Feiertag bremsen uns aus, erst in der zweiten Wochenhälfte ist ein Verantwortlicher aufzutreiben, der Infos liefert. Besser: theoretisch hätte liefern können. Denn sie bringen uns nicht weiter. Eine Übung ist nicht bekannt. Ein Flugzeug könne nicht gestartet sein, weil der Flugplatz an beiden Tagen gesperrt gewesen sei, erklärt André Potzler, Referent für Öffentlichkeitsarbeit bei der siebten "Army Training Command" in Grafenwöhr.
Wir wenden uns an höhere Stellen. Das Luftfahrtbundesamt muss doch wissen, wer hier lärmt und kreist. "Wenn Sie bis jetzt nichts erfahren haben, dann wird es wohl geheim sein", lautet die Auskunft. "Versuchen Sie es bei der Deutschen Flugsicherung. Vielleicht haben die Informationen." Gesagt, getan. Hier ist auch schnell ein Ansprechpartner gefunden. Am Telefon wird die Möglichkeit der Flugspur-Nachverfolgung auf der Internetseite www.DFS.de erklärt. Auch bei späteren schriftlichen Nachfragen gibt es schnelle und unkomplizierte Hilfe. Wir kennen jetzt das Unternehmen, welches das Flugzeug betreibt, aber noch immer nicht den Grund des Fluges. Beim Flieger handelt es sich um eine "Pilatus" im Besitz der Rhein-Mosel-Flug GmbH & Co. KG. Das Unternehmen bestätigt den Flugbetrieb und erklärt, dass hier im Auftrag einer anderen Firma geflogen worden sei. Als Auftraggeber nennt es die E.I.S. Aircraft GmbH.
Telefonate mit der E.I.S Aircraft bringen uns nicht mehr wirklich weiter. Vom Hauptquartier in Euskirchen werden wir an die Außenstelle nach Kiel verwiesen. Und von dort wieder zurück. Kreisverkehr - wie die Flugroute über Parkstein. Nur ein Zufallsanruf bei der Niederlassung in München bringt ein wenig Licht ins Dunkel: Der Gesprächspartner bestätigt, dass das Unternehmen manchmal Auftragsflüge für Bundeswehr und US-Armee plant. Der, der's genauer wissen könnte, ist jedoch nie zu erreichen.
Also wenden wir uns erneut an die Pressestellen von Luftwaffe und Heer. Unisono berichten sie: "Zum angegeben Zeitpunkt fand eine Übung des Artilleriebataillons 131 in den Übungsräumen Kemnath und Mitterteich unter Beteiligung ziviler Luftfahrzeuge statt. Zur Übung wurde ein herkömmliches ziviles Flugzeug zur Verfügung gestellt. Anlass war eine Luftnahunterstützungsübung, bei welcher die Fliegerleitoffiziere den Funkverkehr mit dem Piloten üben." Na also! Oder ...? "Das Flugzeug über Parkstein war jedoch nicht im Auftrag der Bundeswehr in der Luft", heißt es weiter. "Im genannten Zeitraum ist zwar ein zivil registriertes Luftfahrzeug über Parkstein festgestellt worden, aber ohne eine mögliche Korrelation zu einer Beauftragung durch die Bundeswehr. In derselben Woche fand zeitgleich eine Luftnahunterstützungsübung der USAF (Vilseck) in genannten Räumen statt."
Immerhin können wir die Bundeswehr nun ausschließen. Ein letztes Mal fragen wir bei Pressesprecher Potzler von der "Army Training Command" nach. Doch trotz seiner Bemühungen: "Keine neuen Informationen. Keine Übungen unter Verwendung der genannten Maschine."
Es ist zum In-die-Luft-Gehen. Vier Wochen Recherche, unzählige Telefonate, massenweise E-Mails - und die Auftraggeber und die Absichten des Motorfliegers sind noch immer nicht geklärt. Die Bürgerbeschwerden laufen ins Leere: Über Parkstein war ein unbekanntes Flugobjekt unterwegs.
AnsprechpartnerWenn der Bevölkerung weitere Flugbewegungen auffallen, sind die richtigen Ansprechpartner:
Die zuständige Polizeidirektion. Für Parkstein ist das die Polizeiinspektion Neustadt/WN.
Die Beschwerdestelle des Luftamtes Nordbayern. Deren Lärmschutzbeauftragte Reiner Lux wünscht sich, dass die Auftraggeber künftig lokale Behörden und die Presse informieren. "Viele Betroffene wollen Klarheit." (pdtr)
16.10.2017 - Bogenhausen bei München
Am 17.Oktober bekamen wir einen Tel-Anruf von Herrn M. aus Bogenhausen welcher merkwürdige Objekte am Nachthimmel beobachten konnte, einmal gegen 23.30, sowie 3.30 und 6.30 MESZ. Teilweise nur ein weißes Licht dann auch mit grünen und roten Blinklicht. Normale Flugzeuge die im An- und Abflug des nahen Flughafens wären, würde er kennen und diese "Objekte" würden tiefer und anders aussehen. Per E-Mail bekamen wir dann ein kurzes Handy-Video, auf welchen man typische Antikollisionsbeleuchtung eines Kleinflugzeuges erkennen konnte:
Überprüfungen des Luftverkehrs zu den Beobachtungszeiten, erbrachte dann den Hinweis auf ein Kleinflugzeug der FCS:
Diese Flugzeuge werden zur Calibration der Flughafenanlagen eingesetzt und dies wird natürlich wegen geringerem Flugverkehr auch gerne in der Nacht vorgenommen. Zusätzlich werden neben diesem Flugzeug auch Oktokopter eingesetzt, welche für die rot blinkenden Objekte verantwortlich sein dürften.
Nachfolgende Infos zu der FCS Flight Calibration Services:
Und seit 2016 setzt FCS auch zusätzlich UAS Oktokopter bei großen Flughäfen ein: