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Sonntag, 12. März 2017 - 19:45 Uhr

Astronomie - Licht von einem ultra-kühlen Nachbar

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Kepler animation of light from TRAPPIST-1

This animation shows the amount of light detected by each pixel in a small section of the camera onboard NASA's Kepler space telescope. The light collected from TRAPPIST-1, an ultra-cool dwarf star approximately 40 light-years from Earth, is at the center of the image. Not directly visible in the movie are the seven Earth-size planets that orbit TRAPPIST-1.

 

Kepler detects a change in brightness when a planet passes in front of a star from the vantage point of the telescope. Transiting planets block a tiny fraction of starlight that produces miniscule dips in the brightness of their host star. An Earth-size planet passing in front of a small ultra-cool dwarf star like TRAPPIST-1 creates less than a one percent dip in brightness, and is not visible with the naked eye.

 

Astronomers use sophisticated algorithms to search the data for these dips in brightness, and in particular, to correct for the spacecraft’s small movements in space—this is the 'flickering' of the pixels seen in the movie.

 

During the period of Dec. 15, 2016 and March 4, the Kepler spacecraft, operating as the K2 mission, observed TRAPPIST-1 for 74 days. This animation shows 60 brightness measurements or photos taken by Kepler's onboard camera once a minute for an hour on February 22. Called a target pixel file, the image covers an area of 11 square pixels or 44 square arcseconds of the sky. This area is equivalent in size to holding up a grain of sand at arms length towards the sky.

Quelle: NASA


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Sonntag, 12. März 2017 - 19:30 Uhr

Astronomie - Hubble Hones In on a Hypergiants Home

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This beautiful Hubble image reveals a young super star cluster known as Westerlund 1, only 15,000 light-years away in our Milky Way neighborhood, yet home to one of the largest stars ever discovered.

 

Stars are classified according to their spectral type, surface temperature, and luminosity. While studying and classifying the cluster’s constituent stars, astronomers discovered that Westerlund 1 is home to an enormous star.  Originally named Westerlund 1-26, this monster star is a red supergiant (although sometimes classified as a hypergiant) with a radius over 1,500 times that of our sun. If Westerlund 1-26 were placed where our sun is in our solar system, it would extend out beyond the orbit of Jupiter.

 

Most of Westerlund 1’s stars are thought to have formed in the same burst of activity, meaning that they have similar ages and compositions. The cluster is relatively young in astronomical terms —at around three million years old it is a baby compared to our own sun, which is some 4.6 billion years old.

Quelle: NASA



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Sonntag, 12. März 2017 - 16:30 Uhr

Astronomie - Chinesische Astronomen erneuern Antarktis-Teleskop-Plan

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Chinese astronomers renew Antarctica telescope plan 

 
In 2012, Chinese Antarctic Kunlun Station installed the first of three wide-field Antarctica Schmidt telescopes (AST3).In 2012, Chinese Antarctic Kunlun Station installed the first of three wide-field Antarctica Schmidt telescopes (AST3). (Photo: CNS)

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Chinese astronomers have renewed their ambitious attempt to build two powerful telescopes at Dome A, the highest place in Antarctica.
 
Professor Cui, Deputy Director of the Chinese Centre for Antarctic Astronomy, said the two major telescopes would greatly assist the research of black holes and dark energy, as well as the origins of life and the universe, reported Xinhua News Agency.
 
Both Kunlun Dark Universe Telescope (KDUST), a 2.5-metre survey telescope, and Dome A Terahertz Explorer-5 (DATE5) were originally included in China’s 12th Five Year Plan (2011-2015) but funding has been difficult to secure.

According to Nature, the 5-metre DATE5 would offer a view inside the dark clouds of dust and molecules where astronomers believe stars are forming.
 
Using optical and near-infrared light to detect planets similar to Earth outside the solar system, KDUST could also find clues related to the mystery of dark matter and dark energy, as well as how the first stars were formed. 

“The completion of KDUST would make up for China’s lack of a Hubble telescope […] By observing distant objects in infrared wavelengths, we could expect to achieve a breakthrough in the field of dark energy research,” added Professor Cui, an academic with the Chinese Academy of Sciences and a National Party Congress deputy.

Located at 4,093m above sea level, Antarctica’s Dome A, also known as Dome Argus, ice cap offers unparalleled conditions for stargazing because of its altitude and clean, bone-dry air, as well as reduced background noises for infrared observations.

Quelle: gbtimes

 

 


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Sonntag, 12. März 2017 - 16:00 Uhr

Raumfahrt - Chinas nächste Schritte bei der Raumfahrt und Raumstation Bau

12.03.2017

China's Space Station: Tianhe-1 module to be followed by Tianzhou-2, Shenzhou-12 

 
The Shenzhou-9 spacecraft undergoing tests ahead of its June 2012 launch. The Shenzhou-9 spacecraft undergoing tests ahead of its June 2012 launch. 

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The outline for China's next steps in human spaceflight and space station construction have been announced by a senior official at the main contractor for the country's space programme.

The core module of the Chinese Space Station, Tianhe-1, will be launched in 2018, says Zhang Bainan, chief designer of crewed spacecraft at the China Aerospace Science and Technology Cooperation (CASC).

This will be followed by Tianzhou-2, a cargo and refuelling spacecraft, which will dock with and supply Tianhe-1 in low Earth orbit.

After this the Shenzhou-12 crewed spacecraft will visit Tianhe-1, which is the first of three large modules that will make up the completed Chinese Space Station (CSS).

The launch order was revealed to press in Beijing at the country's ongoing annual parliamentary sessions by Mr. Zhang, whose given name is also pronounced 'Bonan', though no dates were offered.

Construction of the 20 metric tonne Tianhe-1 core module was completed in late 2016 and has entered a testing phase. 
Diagram of the Tianhe-1 Chinese Space Station core module (CMSA).
Above: Rendering of the Tianhe-1 Chinese Space Station core module (CMSA).

Tianhe-1 will be launched from Wenchang by a Long March 5B rocket, a low Earth orbit variant of a new generation heavy-lift launch vehicle that debuted last year and will in November launch a lunar sample return mission, Chang'e-5.

The Tianzhou cargo spacecraft will next month have its first flight via a Long March 7 rocket to test liquid propellant refuelling in microgravity, once it docks with the orbiting Tiangong-2 space lab, a small 8-tonne testbed for CSS modules.

The mission will test and verify the crucial refuelling technologies and processes needed to maintain the future Mir-class CSS.

Shenzhou-12 will be China's seventh crewed spaceflight mission, following Shenzhou-11 last October which doubled the country's record for human spaceflight duration.

Jing Haipeng 'walks' silkworms aboard Tiangong-2.
Above: Jing Haipeng 'walks' silkworms aboard Tiangong-2.

Somewhat confusing matters, Zhang Yulin, deputy commander-in-chief of China's human spaceflight programme, also stated this week that the Long March 5B would launch for the first time in 2019, suggesting a later schedule than announced by others.

"The research and production of the new rocket specially used to launch the space station will be based on Long March 5. There are still some challenges and more research work will be carried out...It will launch the space station in 2019," Zhang said.

Constructing a space station

Bao Weimin, also of CASC, told press earlier this week that from 2018 to completion, the CSS project will require more than a dozen launches, including launching modules, Tianzhou cargo vessels and Shenzhou crewed missions to the facility.

Liu Yang, China's first woman in space, said in an interview this week that the country's astronauts are in training for extravehicular activities - EVAs or 'spacewalks' - and maintenance of the CSS.

A model of the CSS with a Shenzhou vessel docked below, on display during China's first space day in April 2016.
Above: A model of the CSS with a Shenzhou vessel docked below and Tianzhou craft (fore) on display during China's first space day in April 2016.

Two experiment modules named 'Wentian' and 'Mengtian' will join with Tianhe-1 to form the CSS. Smooth progress would see it completed by around 2022. 

The two science modules will feature experiment racks focusing on the areas of space life sciences and biotechnology, microgravity fluid physics and combustion, material science in space, fundamental physics in microgravity and other multi-purpose uses.

Space life science experiment racks for the Chinese Space Station (CMSA),
Above: Space life science experiment racks for the CSS (CMSA).

The CSS will feature two 30-metre solar panels and two robotic arms for construction, repair and docking.

Also expected to be part of the CSS is a free-flying space telescope with a two-metre mirror, dubbed 'China's Hubble'.

The Xuntian module is expected to provide a level of resolution no less than the famous Hubble space telescope, but with a field of view 300 times larger.

An illustration of China's planned Xuntian Hubble-class space telescope.
Above: An illustration of China's Xuntian space telescope.

China began its human spaceflight programme in 1992, and in 2003 became only the third country after the United States and Russia (Soviet Union) to independently put an astronaut - namely Yang Liwei - in space, 

The CSS is the ultimate goal of 'Project 921', which China aims to keep permanently crewed with 3-6 astronauts for at least a decade. 

Tianzhou-1 undergoing testing at the AIT centre in Tianjin, North China (CGTN/Framegrab).
Above: Tianzhou-1 undergoing testing at the AIT centre in Tianjin, North China (CGTN/Framegrab).

Quelle: gbtimes


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Sonntag, 12. März 2017 - 08:15 Uhr

Raumfahrt - Japanische Maschinenhersteller suchen ihr Glück bei den Sternen

12.03.2017

Japanese construction companies hitch their fortunes to the stars

Once the realm of science fiction, space development now has contractors seriously interested

KOSUKE TERAI, Nikkei staff writer

TOKYO -- With an eye to profiting from humankind's final frontier, Japanese construction giants are developing ambitious space technologies to supplant the Olympic building boom. And some of their projects are simply out of this world.

In February, an odd looking device was seen rolling around a highway construction site on Japan's southwestern island of Shikoku, stopping regularly to examine soil hardness. The machine was actually an autonomous rover, the product of a collaboration between Takenaka, one of the nation's largest contractors, its subsidiary Takenaka Civil Engineering & Construction and the Japan Aerospace Exploration Agency (JAXA). Designed for exploring the moon and Mars, it is currently being tested to see if it can collect samples for space-based engineering and construction projects.

 
 

A prototype of the rover, dubbed Kenage, was developed in 2014 by JAXA and Ono Denki Seisakusho, a Japanese machinery manufacturer. It was able negotiate 30-centimeter obstacles and climb 45-degree slopes, but obviously lacked the capability to traverse more rugged terrain like the rocky, pockmarked surface of the moon. That's when Takenaka stepped in. The original developers hoped to leverage the company's expertise in platform cars commonly used at construction sites to advance their goals.

 

 
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Now, the rover has been equipped with ultrasonic sensors and GPS in order to detect and avoid obstacles, thus improving mobility over treacherous landscapes. Testing is also underway at different places around the world to assess the machine's terrestrial capabilities, as the developers would like to exploit more down-to-earth opportunities. "We hope technologies designed for space can also be used for our earth-based business," remarked Masahiro Sugata, a researcher who heads the new production systems unit at Takenaka's Research & Development Institute.

Currently, the biggest challenge still facing project engineers is making a rover that can deal with unexpectedly formidable obstacles. One idea is to integrate multiple robots into a single machine.

The trials in Shikoku proved that the rover can reduce soil inspection times by 15%. JAXA hopes to have a fully functioning version included on its moon missions slated for early next decade.

The idea of exploiting outer space for profit began in the free-spending days of Japan's bubble economy in the 1980s. At the time, some construction companies unveiled otherworldly plans, such as Shimizu's space hotel and moon base -- projects that were laughed off as little more than sci-fi dreams. Since then, new capabilities acquired from participation in numerous infrastructure projects as well as advances in information technology have made spaced-based business a distinct possibility.

Corporations involved in space projects also want to apply the fruits of their labors to infrastructure on earth. Takenaka believes its autonomous moon rover can be used for inspecting road bridges, many of which have complex inner structures that are time-consuming to check. The company is banking on robots to generate substantial savings in time and manpower when used for similar tasks.

Another large Japanese contractor, Tokyu Construction, is developing technology for manufacturing bricklike construction materials on the moon. Since any moon bases would be exposed to meteorites and high levels of radiation, the company figures that lunar facilities would require walls at least 10 meters high for protection. Launching materials from Earth to construct these walls would be impractical, hence the need for this futuristic technology, which would use sand mined from the lunar surface and a minimum of Earth-based materials to make the bricks.

Tokyo City University and Nitto Seimo, a fishing-net manufacturer, have joined the project, which launched last year and involves nearly 20 engineers and researchers. The team has been mixing lunar sand obtained from JAXA with materials found on Earth in order to find just the right blend. They anticipate a solution by late March. Like Takenaka, Tokyu hopes the new technology can be used for more earthly applications.

Quelle: Asian Review


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Sonntag, 12. März 2017 - 08:00 Uhr

Raumfahrt - ASU-Studenten konkurrieren bei Mond-Mission um Cyanobakterien auf Mondoberfläche zu bringen

12.03.2017


Sun Devils working with teammates on the other side of the globe for a chance to induce photosynthesis on our lunar neighbor

Unlocking humanity’s future as an interplanetary species is no simple feat.

But students at Arizona State University and the Central University of Tamil Nadu in India are up for the challenge. The international collaboration is vying for a chance to induce photosynthesis on the moon.

“Photosynthesis is the basis of all life,” said Jonathon Barkl, a physics and economics major in the College of Liberal Arts and Sciences. “If it can happen on another planet, we’re one step closer to proving humanity can eventually do the same.”

The quest to help build sustainable life on the moon started with TeamIndus, the only Indian team competing for the Google Lunar XPRIZE. The $30 million international competition inspires innovators to develop low-cost methods of robotic space exploration and be the first privately funded team to land spacecraft on the moon, travel 500 meters and transmit high-definition video and images back to Earth.

TeamIndus has officially secured a launch contract with India’s Space Research Organization to send a lander to the moon in December 2017. As part of their mission to catalyze humankind as a multi-planetary species, TeamIndus created the Lab2Moon challenge to fly one youth experiment aboard their spacecraft to the moon.  

“We have this amazing opportunity to send a payload to the lunar surface and conduct science that could impact the future of human exploration,” said Barkl, a member of the ASU/CUTN Lab2Moon team. “It blows my mind every time I think about it.” 

During phase one of the challenge, TeamIndus received 3,000 entries from across the globe explaining a range of experiments to catalyze the evolution of humankind – from growing plants on the moon to investigating the lunar subsurface.

Twenty-five teams were shortlisted in the competition to build prototypes of their concept, including the ASU/CUTN Lab2Moon team who are eager to determine if photosynthesis can take place on the moon with its very hostile conditions.

“The premise of our mission is taking cyanobacteria – a really robust and primitive life form – and placing it on the lunar surface to see how it affects the photosynthesis process,” Barkl said. “If cyanobacteria can photosynthesize and thrive on this surface, we can use it as a means of potentially producing energy, food or even possibly terraforming another planet.”

 

The ASU/CUTN Lab2Moon team has been developing a strategy for putting their mission on the moon, from outlining power requirements to maintaining a safe environment for the bacteria. As they start to develop a full-on prototype of their project, they have to meet TeamIndus’ three criteria: be the size of a regular soda can, weigh less than 250 grams and connect to the spacecraft’s on-board computer.

“It’s a unique challenge to coordinate between the two universities,” Barkl said. “We’re halfway around the world and our colleagues are 12.5 hours ahead. We’ll message them while they’re trying to sleep or they’ll message us when we’re in class. The time coordination is hard, but it’s going well.”

During the development stage, the team has broken down responsibilities for the members at each university. Santosh and Sukanya Roychowdhury from CUTN will be developing the space capsule and testing it for space-grade readiness, structural integrity and its ability to withstand pressure and temperature. Barkl, Aidan McGirr and Autumn Conner from ASU will determine how to configure the electronics with the on-board computer, prepare the cyanobacteria and test the capsule’s sensors.

“Our mission is very heavy in science and data because we’re going to have about nine sensors whereas several other teams have only two or three,” Barkl said. “We have two main groups of sensors: one for maintaining a relatively friendly environment for the cyanobacteria and one for measuring the output of photosynthesis as the function of radiation on the lunar surface.”

 

Team of ASU students competing to go to the moon

Members of the Arizona State University and the Central University of Tamil Nadu Lab2Moon team — (from left) Autumn Conner, Jonathon Barkl and Aidan McGirr — along with Rakshith Dekshidar (right), a graduate student in electrical engineering, who has been helping the team configure the space capsule's sensors and electronics systems.

 

After their second design review with TeamIndus, the ASU/CUTN Lab2Moon team was invited to the final stage of the competition. The team will showcase their prototype to an international team of judges in Bangalore, India, on March 13, where they’ll find out who gets to fly with TeamIndus to the moon this year.

“We see professors from the School of Earth and Space Exploration all the time getting research grants from NASA and winning different missions. It’s inspiring to think, ‘Wow, I can go to space too,’ ” Barkl said. “ASU has never had a student mission of this caliber. We want to prove that not only are the faculty doing amazing science, but so are the students.”

Although Barkl is a student in the Department of Physics, he considers himself an honoree member of the School of Earth and Space Exploration. The research being conducted in the school was the reason he decided to attend the university and what inspired him to pursue this competition.

“The ASU community has really been a huge support for us,” Barkl said. “It’s a humbling experience to work with so many inspiring researchers who are so supportive and answer all our questions. If we had three years to research these questions, we could probably figure them out on our own. But with such a short turnaround time, they have really helped us make this project possible.”

The team’s mentors include Lindy Elkins-Tanton, planetary scientist and director of the School of Earth and Space Exploration; Philip Christensen, geologist and geophysicist; Scott Parazynski, retired NASA astronaut and current professor of practice; Ferran Garcia-Pichel, dean of natural sciences in the College of Liberal Arts and Sciences; Mark Jacobs, dean of Barrett, The Honors College and professor in the School of Life Sciences; Mark Naufel, director of strategic projects at the university; and Scott Smas, program manager of ASU’s Space Technology and Science Initiative.

“ASU has provided us with funding, supplies, facilities and mentorship,” Barkl said. “Having access to all these resources has pretty much changed the game for us.”

Barkl and McGirr, an astrophysics major, want to use the Lab2Moon project to kick off a miniature space agency and private, student-run organization at ASU where students can take what they are learning in the classroom and apply it in a meaningful way to advance space technologies.

“What I look forward to most is being able to say I’ve contributed to the goal of human colonization on other planets,” Barkl said. “And we want to prove that students can do meaningful work in the space sector too.”

Quelle: Arizona State University


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Samstag, 11. März 2017 - 07:40 Uhr

Astronomie - Schöne Spekulation: FRBs durch Neutronensterne oder Alien Raumschiff-Antrieb?

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Could fast radio bursts really be powering alien space ships?

 

base

M. Weiss/CfA

 

Are alien radio beams causing one of the most mysterious signals from space? A new study by Manasvi Lingam and Avi Loeb at Harvard says that fast radio bursts (FRBs) could come from extraterrestrial radio beams being used as beacons or to power alien light sails.

The source of FRBs, which are milliseconds-long but incredibly bright pulses of radio waves, have intrigued and mystified astronomers for years – and this isn’t the first time aliens have been suggested.

 

 

What? They found aliens?

No. There is no evidence that FRBs come from aliens. This new research isn’t saying that anyone found aliens or that aliens cause FRBs. Instead, it takes the scenario where these mysterious signals do come from extragalactic civilizations as a starting point, and asks how that could happen.

Since we don’t know what actually causes FRBs, this work is simply adding another idea to the pile. Many astronomers find it unlikely, but Loeb argues it’s worth investigating anyway.

“Deciding what’s likely ahead of time limits the possibilities,” Loeb said in a press release. “It’s worth putting ideas out there and letting the data be the judge.”

If it was aliens, how would that work?

According to Lingam and Loeb, FRB signals could come from enormous radio transmitters outside of our galaxy. If they were powered by sunlight, these alien transmitters would need to be twice the size of Earth. Why make the effort to build a planet-sized radio transmitter? If aliens are trying to signal that they’re out there, this seems like one of the more difficult and inefficient ways to do so.

Instead, maybe they are using these powerful radio beams to power light sails, which push spacecraft along by bouncing light off a large, reflective sheet. A sail that requires a beam as powerful as an FRB would be much bigger than any we’ve ever considered making on Earth. Such an alien light sail could carry almost a million tonnes – in contrast, the International Space Station only weighs about 420 tonnes.

 

If there were many extraterrestrial civilizations with colossal alien cruise ships, there could be many powerful radio beams sweeping through the sky, each following the path of a sail. When the beam’s path intersects with the Earth’s, we’d see a bright but fleeting burst of radio waves.

If fast radio bursts aren’t alien signals, what are they?

Since FRBs probably come from extremely far away, they must come from extraordinarily energetic and bright sources. So most proposed explanations involve the most extreme objects in the universe, neutron stars and black holes.

One theory holds that as a neutron star and a black hole orbit one another and spiral inward, their interacting magnetic fields generate electricity, lighting up the area in radio waves. Just before the two behemoths merge, that light flashes, causing the radio bursts that we see.

Or maybe FRBs come from neutron stars in the process of becoming black holes. If a supernova left behind an overweight neutron star, only its fast rotation would stop it from immediately collapsing into a black hole. Eventually, though, the neutron star has to give in to gravity. When it does, its magnetic field may be severed, releasing a burst of energy – maybe in the form of an FRB.

Is there anything else it could be?

One FRB appears to repeat, which throws a wrench into the idea that they must come from cataclysmic one-time events. Repetition could point to “something like a pulsar on steroids”, a rotating source that occasionally emits bursts of radio waves in our direction, said Jason Hessels of the Netherlands Institute for Radio Astronomy, who was part of the team that discovered the repeating FRB.

It’s also possible FRBs are caused by a combination of things, or by something else that nobody’s thought of yet. We’ve only seen 17 unique FRBs so far, so it’s hard to say with any confidence what causes them.

So… it could still be aliens?

Well, nobody has proven that it definitely isn’t aliens or that it definitely is any other source… So technically, yes, it could still be aliens. We’ll leave it to you to decide how likely that is.

Quelle: New Scientist


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Samstag, 11. März 2017 - 07:30 Uhr

Planet Erde - Ist dies die Dämmerung für das Goldene Zeitalter der Erdbeobachtung in den USA?

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Is This Twilight for the Golden Age of Earth Observation? 

A flying satellite with several green beam projecting down to a cliff of ice
Illustration: Goddard Space Flight Center/NASA

When leaders of the Congressional committees that approve NASA’s missions and budgets put forth their priorities in February, only space science and deep space exploration made the cut. Conspicuously absent was Earth science—a US $2 billion function within NASA that tracks our rapidly changing “home planet.”

Add in White House skepticism of climate science, and what experts call today’s “golden age” of monitoring Earth via satellite faces some serious challenges.

That age began in 2009, when President Barack Obama responded to a U.S. National Research Council warning that budget cuts had left the United States’ Earth observing system “at risk of collapse.” NASA, the lead federal agency for satellite development, saw its Earth science budget rise 56 percent between 2008 and 2016, and it placed eight new Earth-observing satellites in orbit during that period packing state-of-the-art sensors.

The data they deliver inform a widening range of activities—crop planning and management, wildfire risk assessment, extreme air pollution warnings, and more. NASA delivered 1.42 billion data products in 2015—174 times as many as it delivered in 2000—according to a November 2016 review by the agency’s Inspector General.

More missions are in the pipeline, such as NASA’s second Ice, Cloud, and land Elevation Satellite (ICESat-2), whose primary objectives are tracking melting polar ice sheets and glaciers and quantifying the carbon locked up in the globe’s forests.

ICESat-2, however, exemplifies both the present strength of the U.S. Earth observation program and a less visible weakness. To understand why, you need a sense of the ambitious nature of ICESat-2’s mission.

Rather than rerunning the first ICESat mission, which ended in 2009, NASA redesigned the laser altimeter to boost its impact. One laser beam firing sporadically became six beams firing 365 days a year; higher-precision digital photon counting replaced analog detection of beams bouncing back from Earth.

ICESat-2 should enable measurement of annual elevation changes in ice sheets at ± 4-millimeter accuracy (and better for other targets), and at 17 times the spatial resolution of its predecessor, according to Thorsten Markus, chief of cryospheric sciences at NASA’s Goddard Space Flight Center, in Maryland. Such data, he says, will elucidate some basic physical processes that elude climate models, and thus improve their predictions.

But pushing for the best has not come cheap. Instead of $300 million for an ICESat rerun, NASA’s estimate for ICESat-2’s development started at $559 million and has grown to $764 million. Including operations for up to seven years, the mission could cost nearly $1.1 billion, according to that November Inspector General report. Launch dates, meanwhile, have slipped from 2015 to 2018.

Delays and cost creep in ICESat-2 and other missions, as well as several failed launches, put a significant tarnish on Earth observation’s golden age. Extending existing missions to avoid gaps in observational data creates risk, according to NASA’s Inspector General: “More than half the Agency’s 16 operating missions have surpassed their designed lifespan and are increasingly prone to failures that could result in critical data loss….”

Similar risks confront the National Oceanic and Atmospheric Administration, a key partner in climate and weather observation, according to a February report by Congress’s watchdog agency the Government Accountability OfficeNOAA’s polar readings currently come from a dying NASA demonstration mission. If it fails before the agencies’ long-awaited Joint Polar Satellite System launches, it would degrade weather forecasts, “exposing the nation to a 15 percent chance of missing an extreme weather event forecast,” writes the GAO.

If the golden age of Earth observation harbored weak spots before the 2016 election, experts say the new administration introduces new risks. One is the $54 billion in belt-tightening proposed for federal agencies by President Donald Trump. In early March the Washington Post reported that the President will ask for 17 percent less funding for NOAA.

Another is potential interference with climate science. In February, Lamar Smith, chairman of the House Committee on Science, Space, and Technology, called for “rebalancing” of NASA’s portfolio. A former chairman, Robert Walker, now a lobbyist for space-related industries, built a similar plank into the space platform that he drafted for Trump’s campaign. Both men question human-induced climate change—a view held by many Republicans in Congress and Trump appointees.

Walker says expanded Earth observation under Obama came at the expense of other science programs, particularly deep space robotic missions. He also alleges that NASA science was “tainted" by a political agenda against fossil fuels, focusing on impacts from burning coal, oil, and natural gas and neglecting natural climate influences such as volcanic eruptions. “There’s an extremely complex system that involves a lot more than CO2,” he says.

The Intergovernmental Panel on Climate Change’s 2014 assessment, however, expressed “very high confidence” that volcanic eruptions caused only “a small fraction” of the warming observed since the Industrial Revolution. And it cites “robust evidence” from satellite data showing that natural factors have had “near-zero” effect since 1980.

The notion that human activities alter climate is not a political invention, but a scientific judgement based on gigabytes of data downloaded daily from a gilded era’s orbiting sensors. “It’s not a belief,” says NASA’s Markus. “That’s what the data show.”

Quelle: IEEE


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Samstag, 11. März 2017 - 07:20 Uhr

Raumfahrt - Neue NASA Radar Technik findet verlorene Mond Sonde Chandrayaan-1

10.03.2017

 
 
 
Deep Space Network
 
This computer generated image depicts the Chandrayaan-1's location
 
 
 
Radar imagery acquired of the Chandrayaan-1 spacecraft as it flew over the moon's south pole on July 3, 2016. The imagery was acquired using NASA's 70-meter (230-foot) antenna at the Goldstone Deep Space Communications Complex in California. This is one of four detections of Chandrayaan-1 from that day. Image credit: NASA/JPL-Caltech 
› Larger view

Finding derelict spacecraft and space debris in Earth's orbit can be a technological challenge. Detecting these objects in orbit around Earth's moon is even more difficult. Optical telescopes are unable to search for small objects hidden in the bright glare of the moon. However, a new technological application of interplanetary radar pioneered by scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, has successfully located spacecraft orbiting the moon -- one active, and one dormant. This new technique could assist planners of future moon missions.

"We have been able to detect NASA's Lunar Reconnaissance Orbiter [LRO] and the Indian Space Research Organization's Chandrayaan-1 spacecraft in lunar orbit with ground-based radar," said Marina Brozovic, a radar scientist at JPL and principal investigator for the test project. "Finding LRO was relatively easy, as we were working with the mission's navigators and had precise orbit data where it was located. Finding India's Chandrayaan-1 required a bit more detective work because the last contact with the spacecraft was in August of 2009."

Add to the mix that the Chandrayaan-1 spacecraft is very small, a cube about five feet (1.5 meters) on each side -- about half the size of a smart car. Although the interplanetary radar has been used to observe small asteroids several million miles from Earth, researchers were not certain that an object of this smaller size as far away as the moon could be detected, even with the world's most powerful radars. Chandrayaan-1 proved the perfect target for demonstrating the capability of this technique.

While they all use microwaves, not all radar transmitters are created equal. The average police radar gun has an operational range of about one mile, while air traffic control radar goes to about 60 miles. To find a spacecraft 237,000 miles (380,000 kilometers) away, JPL's team used NASA's 70-meter (230-foot) antenna at NASA's Goldstone Deep Space Communications Complex in California to send out a powerful beam of microwaves directed toward the moon. Then the radar echoes bounced back from lunar orbit were received by the 100-meter (330-foot) Green Bank Telescope in West Virginia.

Finding a derelict spacecraft at lunar distance that has not been tracked for years is tricky because the moon is riddled with mascons (regions with higher-than-average gravitational pull) that can dramatically affect a spacecraft's orbit over time, and even cause it to have crashed into the moon. JPL's orbital calculations indicated that Chandrayaan-1 is still circling some 124 miles (200 kilometers) above the lunar surface, but it was generally considered "lost." 

However, with Chandrayaan-1, the radar team utilized the fact that this spacecraft is in polar orbit around the moon, so it would always cross above the lunar poles on each orbit. So, on July 2, 2016, the team pointed Goldstone and Green Bank at a location about 100 miles (160 kilometers) above the moon's north pole and waited to see if the lost spacecraft crossed the radar beam. Chandrayaan-1 was predicted to complete one orbit around the moon every two hours and 8 minutes. Something that had a radar signature of a small spacecraft did cross the beam twice during four hours of observations, and the timings between detections matched the time it would take Chandrayaan-1 to complete one orbit and return to the same position above the moon's pole.

The team used data from the return signal to estimate its velocity and the distance to the target. This information was then used to update the orbital predictions for Chandrayaan-1. 

"It turns out that we needed to shift the location of Chandrayaan-1 by about 180 degrees, or half a cycle from the old orbital estimates from 2009," said Ryan Park, the manager of JPL's Solar System Dynamics group, who delivered the new orbit back to the radar team. "But otherwise, Chandrayaan-1's orbit still had the shape and alignment that we expected." 

Radar echoes from the spacecraft were obtained seven more times over three months and are in perfect agreement with the new orbital predictions. Some of the follow-up observations were done with the Arecibo Observatory in Puerto Rico, which has the most powerful astronomical radar system on Earth. Arecibo is operated by the National Science Foundation with funding from NASA's Planetary Defense Coordination Office for the radar capability.

Hunting down LRO and rediscovering Chandrayaan-1 have provided the start for a unique new capability. Working together, the large radar antennas at Goldstone, Arecibo and Green Bank demonstrated that they can detect and track even small spacecraft in lunar orbit. Ground-based radars could possibly play a part in future robotic and human missions to the moon, both for a collisional hazard assessment tool and as a safety mechanism for spacecraft that encounter navigation or communication issues.

JPL manages and operates NASA's Deep Space Network, including the Goldstone Solar System Radar, and hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program, an element of the Planetary Defense Coordination Office within the agency's Science Mission Directorate.

Quelle: NASA

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Update: 11.03.2017

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Chandrayaan-I, 'lost' in Aug. 2009, now found by NASA

A model of Chandrayaan-1. File Photo   | Photo Credit: V_Ganesan

 

Calculations suggest that the spacecraft, "lost" since Aug. 2009, is still circling some 200 km above the lunar surface, but it was generally considered "lost."

NASA’s Jet Propulsion Laboratory, using a new interplanetary radar technology, has spotted India's Chandrayaan 1, which has been out of radio contact since August 2009. 

"We have been able to detect NASA’s Lunar Reconnaissance Orbiter [LRO] and the Indian Space Research Organisation’s Chandrayaan-1 spacecraft in lunar orbit with ground based radar," said Marina Brozovic, a radar scientist at JPL and principal investigator of the test project, in a press note released by JPL on Thursday. 

"Finding LRO was relatively easy, as we were working with the mission's navigators and had precise orbit data where it was located. Finding Chandrayaan-1 required a bit more detective work because the last contact with the spacecraft was in August 2009."

"Although the interplanetary radar has been used to observe small asteroids several million miles from the Earth, researchers were not certain that an object of this smaller size as far away as the moon could be detected, even with the world's most powerful radars," the press note added. 

Optical telescopes are unable to search for small objects hidden in the bright glare of the moon.

 

Chandrayaan-1, India’s first moon mission, was launched on October 22, 2008. It was successfully placed in a polar orbit around the moon on November 8, 2008. The Moon Impact Probe was placed on the moon on November 14, 2008, and with this India became the fourth country to touch the moon. 

Analysing the soil collected by the impact probe, Indian scientists found evidence of the existence of water on the moon. The mission was expected to last for two years; however, after 312 days, it had to be closed, as the station lost track of the spacecraft on August 29, 2009.

Finding a dormant spacecraft around the moon is difficult, since its orbital path could have varied over time, or even crashed on the moon. JPL's calculations suggest that Chandrayaan-1 is still circling some 200 km above the lunar surface, but it was generally considered "lost." 

As Chandrayaan-1 is in a polar orbit around the moon, the scientists aimed the radar at a location above the moon’s north pole and waited for the satellite to pass the radar beam. "Chandrayaan-1 was predicted to complete one orbit around the moon every two hours and 8 minutes. Something that had a radar signature of a small spacecraft did cross the beam twice during four hours of observations, and the timings between detections matched the time it would take Chandrayaan-1 to complete one orbit and return to the same position above the moon’s pole," the press note said. Seven more readings over the next three months confirmed that it is indeed Chandrayaan.

India's second moon mission Chandrayaan-2 is expected to be launched at the end of 2018.

Quelle: The Hindu

 


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Samstag, 11. März 2017 - 07:10 Uhr

Astronomie - NASA Direktor der Planetenwissenschaften Jim Green glaubt, wir bis 2027 Planeten mit erdähnlichen Atmosphären finden

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Extraterrestrial life answer soon at hand: NASA

NASA director of planetary science Jim Green believes humanity will discover whether other planets with Earth-like atmospheres exist by 2027. 
NASA Web
NASA director of planetary science lectures at Lakehead University on Wednesday evening. 

THUNDER BAY -- If life exists beyond this planet, a NASA director visiting the city this week believes we'll know within the next decade. 

"We may or may not find life beyond Earth but I think in the next 10 years, we'll be able to answer the question, 'is there life beyond our solar system,'" NASA director of planetary science Jim Green said at a Lakehead University lecture on Wednesday evening. 

"We'll go to the right places, we'll interrogate those places where there's a significant amount of water there might have been life in the past and we'll really take a good look to see if we can find it." 

Green said space exploration has made incredible strides in the past half-century since Neil Armstrong's mission to the moon in 1969. NASA has a deep perspective on this solar system's planets and is beginning to gain perspective on the universe beyond.  

 

The recent discovery of seven planets in the TRAPPIST-1 system has unleashed the imaginations of astronomists. The possibility of one or more planets orbiting their star within a habitable distance to sustain human life has re-ignited the discussion of life in outer space among the public.   

Although scientists don't know whether planets in the recent discovery have atmosphere, water or life, Green pointed out the very fact they exist so close to Earth is reason enough to be optimistic. 

"The seven planets we discovered are only 40 light years away. That's in our neighbourood. That's right on our block," he said.  

"Their significance tells us there's a lot of planet-making material all around us so we'll be looking for other stars with planets that are more Earth-like."  

Quelle: tbnewswatch


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