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Samstag, 31. Dezember 2016 - 17:30 Uhr

Raumfahrt - Virgin Galactic plant Raketen, die kleine Satelliten starten

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SATELLITE LAUNCH

We’re Building Rockets That Will Launch The Small Satellite Revolution

While every other gadget in our lives has gotten smaller, lighter, and cheaper, satellite technology spent decades after the launch of Sputnik and Explorer I getting bigger, heavier, and more expensive. But recently, the rise of cubesats and microsatellites has meant that at last, commercial satellite start-ups, universities, schools, and even crowdfunding campaigns can put their own satellites into space. However, small satellites need small satellite launch vehicles—after all, small satellites cannot truly change the world without cost-effective, frequent rides to space!

Most of the small and microsatellites that have already reached space have done so by “hitchhiking” — catching a ride on someone else’s big, expensive rocket. Hitchhiking to space has real drawbacks: just like hitchhiking here on Earth, when you leave and where you get dropped off aren’t your decisions to make, there are very strict rules about what you can and can’t do during the ride. Those restrictions may be fine if your only goal is to prove that your satellite works in space, but if you are trying to build a business or accomplish a mission, you need your own ride, to the right destination and at the right price.

The makers, builders, and satellite entrepreneurs have done their part. It’s time for the rockets to do theirs. It’s time for LauncherOne.

At Virgin Galactic, we are leveraging our work building our human spaceflight program and our team’s extensive background in low-cost launch systems to create LauncherOne, an orbital launch vehicle dedicated to the small satellite market. Already, our world-class team of 150 experienced professionals are hard at work in our 150,000 square foot manufacturing and design facility, helping make this system a reality. We’ve built and tested real hardware, acquired a 747-400 to serve as our dedicated carrier aircraft, and signed up both commercial and government customers to real launch contracts. With real hardware built and real results achieved, we are well on our way towards a vehicle that will meet our customers’ needs for launch reliability, availability and flexibility, at a commercial price they can afford.

LauncherOne customers will use their satellites to conduct a staggering array of missions. Some will further the exploration of space, others will directly focus on improving life here on Earth. Already, satellite manufacturers have presented plans to use LauncherOne to launch missions to provide broadband internet to billions of people who are currently without internet access, to take pictures of the Earth for humanitarian causes, to collect more accurate weather measurements, to hunt for asteroids that could represent threats and opportunities to our home planet, and to launch many other types of satellites. We’re convinced that the types of missions are only the tip of the proverbial iceberg.

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Providing Affordable, Reliable And Flexible Launch For A New Generation Of Satellites

Governments, companies, and even individuals all around the world are now building incredibly innovative small satellites. Once a team of satellite innovators has invested their time and money perfecting their satellite technology, they don’t want to sit around waiting for a launch date that could be years in the future. The world’s leading satellite inventors deserve a launch vehicle that works the way their satellites work. That’s why LauncherOne is built to support quick, responsive, and affordable cubesat and microsatellite missions.

LauncherOne has been designed from the start to be affordable, reliable, flexible, and responsive. We accomplish those ambitious goals through the way we design the system, the way we build it, and way we operate it. One critically important aspect of our method is the way we launch our system.

Rather than launching from a traditional launch pad at a spaceport, LauncherOne is launched from our dedicated 747-400 carrier aircraft, called Cosmic Girl.

 

Cosmic Girl will carry LauncherOne to at an altitude of approximately 35,000 feet before releasing the launch vehicle to begin its rocket-powered flight to orbit. Starting each mission with an airplane rather than a traditional launch pad offers performance benefits in terms of payload capacity, but more importantly, air-launch offers an unparalleled level of flexibility. LauncherOne will operate from a variety of locations independently of traditional launch ranges—which are often congested with traffic—and will have the ability operate through or around a variety of weather conditions and other impediments that delay traditional launches.

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Once released from the carrier aircraft, the LauncherOne rocket fires up its single main stage engine, a 73,500 lbf, LOX/RP-1 rocket engine called the “NewtonThree.” Typically, this engine will fire for approximately three minutes. After stage separation, the single upper stage engine, a 5,000 lbf LOX/RP-1 rocket engine called the “NewtonFour” will carry the satellite(s) into orbit. Typically, the second stage will execute multiple burns totaling nearly six minutes. Both the NewtonThree and the NewtonFour are highly reliable liquid rocket engines designed, tested, and built by Virgin Galactic.

At the end of this sequence, LauncherOne will deploy our customers’ satellite (or satellites) into their desired orbit. Both stages of LauncherOne will be safely deorbited, while the carrier aircraft will return to a predetermined airport, where it can be quickly prepared for its next flight.

Quelle: Virgin Galactic


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Samstag, 31. Dezember 2016 - 13:30 Uhr

UFO-Forschung - IFO-Universität: Gas-Ballons

Es müssen nicht immer nur die Himmelslaternen und LED-Ballons sein welche in den Abendstunden für Verwirrung sorgen können, auch bemannte Gas-Ballons fliegen bzw. fahren bei entsprechenden Wetterlagen am Himmel:

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Kein Ufo, sondern ein Gasballon

 
 

Ein Leser unserer Zeitung wunderte sich jetzt über Ballonfahrer zu beinahe nächtlicher Stunde über dem nördlichen Oberhausener Stadtgebiet. Die Redaktion fragte nach: Tatsächlich nutzte der Niederrheinische Verein für Luftschifffahrt 1902 e.V. (Ballonstartplatz Gladbeck) die aktuelle gute Phase des Winterwetters für insgesamt drei Ballons-Starts vom Startplatz in Gladbeck-Wittringen aus.

Einer dieser Ballons wurde beispielsweise von Pilot Matthias Zenge gesteuert, der von Gasballon-Weltrekordler Wilhelm Eimers begleitet wurde. Dieser Ballon machte von Gladbeck aus eine große Kurve über die Region, flog zuerst über Essen und dann auch über Oberhausen und das Centro weiter in Richtung der niederländischen Grenze bis Hengelo. Gasballons können über 90 Stunden in der Luft bleiben und verfügen – im Gegensatz zu Heißluftballons – über keinen Brenner, so dass vor allem auch ihr lautloses nächtliches Fahren bei vielen Beobachtern für ein besonderes Erstaunen sorgt. So war es nun auch in Oberhausen.

Quelle: IKZ

 


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Samstag, 31. Dezember 2016 - 11:30 Uhr

Astronomie - Entwicklung von Spektrum-RG Röntgenobservatorium

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New equipment funded for Joint Russian-German Spektrum-RG Observatory
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The future Spektrum-RG observatory

Replacing electronic equipment for the future Spektrum-RG observatory due to the new estimates of radiation levels cost German participants of this project about five million euros (approximately $5.2 million), Mikhail Pavlinsky, the head of Russian Space Research Institute, said Tuesday.

The Spektrum-RG is an X-ray observatory project run jointly by a number of space agencies, including Russian Federal Space Agency (Roscosmos) and German Space Agency (DLR).

"We have considered a low Earth orbit, close to the equator. Unfortunately, the radiation levels are different at the L-point, so all the electronic equipment had to be replaced. Our German partners said that moving from one orbit to another cost about five million euros," Pavlinsky said.

The Spektrum-RG observatory is supposed to be placed at Lagrange point L2, one of several orbital locations where gravitational forces of two large celestial bodies balance out a centrifugal force of a smaller third body, stabilizing the latter and making L-points perfect for the observatories.

Spektrum-RG is expected to be launched in the spring of 2018 with eRosita X-ray grazing-incidence mirror telescope and ART-XC X-ray mirror telescope as its two principal instruments.

Quelle: SD


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Samstag, 31. Dezember 2016 - 11:00 Uhr

Astronomie - NASAs NEOWISE Mission Spies One Comet, Maybe Two

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NASA's NEOWISE mission has recently discovered some celestial objects traveling through our neighborhood, including one on the blurry line between asteroid and comet. Another--definitely a comet--might be seen with binoculars through next week. 

An object called 2016 WF9 was detected by the NEOWISE project on Nov. 27, 2016. It's in an orbit that takes it on a scenic tour of our solar system. At its farthest distance from the sun, it approaches Jupiter's orbit. Over the course of 4.9 Earth-years, it travels inward, passing under the main asteroid belt and the orbit of Mars until it swings just inside Earth's own orbit. After that, it heads back toward the outer solar system. Objects in these types of orbits have multiple possible origins; it might once have been a comet, or it could have strayed from a population of dark objects in the main asteroid belt.

2016 WF9 will approach Earth's orbit on Feb. 25, 2017. At a distance of nearly 32 million miles (51 million kilometers) from Earth, this pass will not bring it particularly close. The trajectory of 2016 WF9 is well understood, and the object is not a threat to Earth for the foreseeable future.

A different object, discovered by NEOWISE a month earlier, is more clearly a comet, releasing dust as it nears the sun. This comet, C/2016 U1 NEOWISE, "has a good chance of becoming visible through a good pair of binoculars, although we can't be sure because a comet's brightness is notoriously unpredictable," said Paul Chodas, manager of NASA's Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California.

As seen from the northern hemisphere during the first week of 2017, comet C/2016 U1 NEOWISE will be in the southeastern sky shortly before dawn. It is moving farther south each day and it will reach its closest point to the sun, inside the orbit of Mercury, on Jan. 14, before heading back out to the outer reaches of the solar system for an orbit lasting thousands of years. While it will be visible to skywatchers at Earth, it is not considered a threat to our planet either.

NEOWISE is the asteroid-and-comet-hunting portion of the Wide-Field Infrared Survey Explorer (WISE) mission. After discovering more than 34,000 asteroids during its original mission, NEOWISE was brought out of hibernation in December of 2013 to find and learn more about asteroids and comets that could pose an impact hazard to Earth. If 2016 WF9 turns out to be a comet, it would be the 10th discovered since reactivation. If it turns out to be an asteroid, it would be the 100th discovered since reactivation.

What NEOWISE scientists do know is that 2016 WF9 is relatively large: roughly 0.3 to 0.6 mile (0.5 to 1 kilometer) across. 

It is also rather dark, reflecting only a few percent of the light that falls on its surface. This body resembles a comet in its reflectivity and orbit, but appears to lack the characteristic dust and gas cloud that defines a comet. 

"2016 WF9 could have cometary origins," said Deputy Principal Investigator James "Gerbs" Bauer at JPL. "This object illustrates that the boundary between asteroids and comets is a blurry one; perhaps over time this object has lost the majority of the volatiles that linger on or just under its surface."

Near-Earth objects (NEOs) absorb most of the light that falls on them and re-emit that energy at infrared wavelengths. This enables NEOWISE's infrared detectors to study both dark and light-colored NEOs with nearly equal clarity and sensitivity. 

"These are quite dark objects," said NEOWISE team member Joseph Masiero, "Think of new asphalt on streets; these objects would look like charcoal, or in some cases are even darker than that." 

NEOWISE data have been used to measure the size of each near-Earth object it observes. Thirty-one asteroids that NEOWISE has discovered pass within about 20 lunar distances from Earth's orbit, and 19 are more than 460 feet (140 meters) in size but reflect less than 10 percent of the sunlight that falls on them. 

The Wide-field Infrared Survey Explorer (WISE) has completed its seventh year in space after being launched on Dec. 14, 2009.

Quelle: NASA


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Freitag, 30. Dezember 2016 - 19:45 Uhr

Astronomie - Planeten-Spechteln am Jahresende

Nach vielen Tagen mit Wolken und Nebel gab es in den letzten STunden des Jahres noch gute Spechtel-Momente für die auffälligen Planeten am Himmel:

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Venus am Südwesthimmel und Jupiter+Spica Duo am Morgenhimmel...

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Fotos: ©-hjkc


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Freitag, 30. Dezember 2016 - 19:30 Uhr

Raumfahrt-History - 1983 Space-Shuttle STS-9 Columbia

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STS-9
 
 
Mission: Orbital Laboratory and Observations Platform/First Spacelab Mission
First Rollback/First 6 Crew Member Flight
Space Shuttle: Columbia
Launch Pad: 39A 
Launch Weight: 247,619 pounds
Launched: November 28, 1983 at 11:00:00 a.m. EST
Landing Site: Edwards Air Force Base, Calif.
Landing: December 8, 1983 at 3:47:24 a.m. PST
Landing Weight: 220,027 pounds
Runway: 17
Rollout Distance: 8,456 feet
Rollout Time: 53 seconds
Revolution: 167
Mission Duration: 10 days, 7 hours, 47 minutes and 24 seconds 
Returned to KSC: December 15, 1983
Orbit Altitude: 155 nautical miles
Orbit Inclination: 57 degrees
Miles Traveled: 4.3 million 

Crew Members

                   STS-9 Crew Photograph

Image above: STS-9 Crew photo with Commander John W. Young, Pilot Brewster H. Shaw Jr., Mission Specialists Owen K. GarriottRobert A. R. Parker and Payload Specialists Byron K. Lichtenberg and Ulf Merbold of the European Space Agency. Image Credit: NASA 

Launch/Landing Highlights

STS-9 Mission PatchThe launch set for Sept. 30 was delayed 28 days due to a suspect exhaust nozzle on the right solid rocket booster. The problem was discovered while the shuttle was on the launch pad. The shuttle returned to the Vehicle Assembly Building (VAB) and was demated. The suspect nozzle was replaced and the vehicle restacked. The countdown on Nov. 28 proceeded as scheduled.

The landing was delayed approximately eight hours to analyze problems when general purpose computers one and two failed and inertial measurement unit one failed. During landing, two of three auxiliary power units caught fire.

Mission Highlights

This flight carried first Spacelab mission and first astronaut to represent the European Space Agency (ESA), Ulf Merbold of Germany. ESA and NASA jointly sponsored the Spacelab-1 and conducted investigations which demonstrated the capability for advanced research in space. Spacelab is an orbital laboratory and contains an observations platform composed of cylindrical pressurized modules and U-shaped unpressurized pallets which remain in the orbiter's cargo bay during flight. Altogether 73 separate investigations were carried out in astronomy and physics, atmospheric physics, Earth observations, life sciences, materials sciences, space plasma physics and technology. This was the first time six persons were carried into space on a single vehicle.
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Frams von STS-9 Columbia-Spacelab1-Mission NASA-Video:
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Quelle: NASA
 
 
 
 
 
 

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Freitag, 30. Dezember 2016 - 16:00 Uhr

Mars-Chroniken - Gasconade, wurde von Mars Rover Opportunity untersucht

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This relatively bright outcropping of rock, dubbed "Gasconade," was investigated by NASA's Mars Exploration Rover Opportunity while the rover was perched on "Spirit Mound" at the western edge of Mars' Endeavour Crater.

 

This mosaic combines four frames taken by the microscopic imager on Opportunity's robotic arm on Oct. 2, 2016, during the 4,512st Martian day, or sol, of the rover's work on Mars. Enhanced color information from Opportunity's panoramic camera has been added to emphasize differences in the materials visible in the target. Figure A is a version with no color information added to the microscopic imager mosaic.

 

The view covers an area about 2 inches (5 centimeters) wide. Opportunity's inspection found Gasconade to be a wind-etched outcrop with angular bits of darker rock within a lighter matrix, which may have been formed from fallout of the impact event that excavated the crater.

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Opportunity View of 'Private Joseph Field' on Mars

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This image of a target called "Private Joseph Field" combines four images from the microscopic imager on the robotic arm of NASA's Mars Exploration Rover Opportunity, with enhanced color information added from the rover's panoramic camera.

Figure A is a version without the added color information.

This target is within the "Marathon Valley" area of the western rim of Endeavour Crater. The component images were taken on May 29, 2016, during the 4,389th Martian day, or sol, of Opportunity's work on Mars. The mosaic shows an area spanning about 2 inches (5 centimeters).

Geochemical data indicate the presence of magnesium and iron sulfates at this location, most likely corresponding to the white pebble visible near the center of the image. These sulfates may have formed by the interaction of acidic fluids with the rocks along the rim of Endeavour crater.

Quelle: NASA


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Freitag, 30. Dezember 2016 - 08:20 Uhr

Raumfahrt - NASA will einen riesigen Raum-Laser verwenden um Plankton zu studieren

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NASA's Got a Giant Space Laser and It's Not Afraid to Use It (To Study Plankton)

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Using an enormous laser tucked into a satellite orbiting Earth, NASA scientists have been locked in intent 
study of polar phytoplankton and the cycles of these tiny plants that are the foundation of coastal and oceanic food chains.

“It’s really important for us to understand what controls these boom-and-bust cycles, and how they might change in the future so we can better evaluate the implications on all other parts of the food web,” Michael Behrenfeld, a marine plankton expert at Oregon State University, stated in the release. 

NASA has been studying the way plants grow in oceans using the Cloud-Aerosol LIdar with Orthogonal Polarization (a.k.a. CALIOP), aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (a.k.a. CALIPSO), a satellite that measures plankton through the clouds. 

Before these tools were launched, in 2006, NASA could only measure the amount of plankton in the ocean by using satellites that could track the plankton when the sunlight was reflected off of ocean water. But the new LIdar system doesn't need outside sources of light to gauge the amount of plankton. And NASA has found out all kinds of stuff about phytoplankton. 

Polar phytoplankton may not sound that interesting, but the microscopic marine plants play a major role in the planet's carbon cycle. Specifically, the plankton, which contains chlorophyll and floats on the upper parts of the oceans where it can catch the sunlight required to live, sucks up and absorbs a lot of the carbon dioxide that gets produced and ends up in the upper parts of the oceans. 

The microalgae are also the main food source for all kinds of sea creatures, from shrimp to whales, when the ecosystem is balanced. When the ecosystem is out of whack and there are too many nutrients, the phytoplankton can grow out of control and form harmful algae blooms, like the red tide algae that has cropped up along the Gulf Coast so often in recent years, screwing up the oyster seasons and poisoning fish. 

After years of observation using that huge laser (it's not like the Death Star so nothing gets destroyed, hurt or even uncomfortably tingly when the laser is used), NASA scientists concluded that even the smallest environmental changes have major effects on the amount of phytoplankton growing, and vice versa. 

If phytoplankton grows too fast and outgrows the animals that eat it, the ecosystem falls out of balance, which allows large plankton blooms to spring into being. However, as soon as the plankton stops growing so fast, the animals that like to eat the nutrient-rich plankton gobble it up and everything snaps back into balance. (This goes against the traditional theory that plankton would start growing too fast on its own and then would stop growing too fast, also on its own, according to NASA.)

The study also reveals that while the year-to-year push-me-pull-you between predator (the organisms that eat phytoplankton) and prey (the phytoplankton) has been the primary driver of change in Arctic plankton stocks over the past decade, it hasn't been the only factor. The study also found that in the Southern Ocean around Antarctica, the changes in ice coverage — like, let's say, the melting of the polar ice caps, for instance — has had just as large an effect on phytoplankton growth as the balance of the food chain. 

In other words, when it comes to phytoplankton, everything matters, and phytoplankton matters a lot to us, since these tiny plants suck the carbon dioxide out of the atmosphere so that Earth remains a place where we can, you know, breathe. 

NASA's research is a big deal because it upends traditional theory about how phytoplankton responds to its environment. This discovery is also important since it may mark one of the last revelations NASA gets to unearth earth-science-wise before the space agency is officially in new hands with new missions and focuses. 

While President Barack Obama pushed hard on Earth science studies,President-elect Donald Trump has already made clear he will be doing pretty much the exact opposite of that. So savor this new bit of information about the tiny plants that play a major role in life on Earth, because Trump's administration isn't interested in this research. 

Quelle: Houston Press


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Freitag, 30. Dezember 2016 - 08:10 Uhr

Astronomie - Ein Komet (45P / Honda-Mrkos-Pajdušáková) fliegt an der Erde am Silvesterabend vorbei. Nein, es ist kein Zeichen der Apokalypse.

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A comet will fly past Earth on New Year's Eve. No, it's not a sign of the apocalypse.

 

If you're looking for an extra dose of fireworks this New Year's Even, look to the skies for the chance to see a comet that only comes around every five years.

The comet — named Comet 45P/Honda-Mrkos-Pajdušáková — is set to appear somewhere near the crescent moon on Dec. 31. It won't be visible to the naked eye, however. 

Interested skywatchers will need a set of binoculars or a small telescope to really be able to see the comet in clear skies.

While comets have historically been seen as bad omens, Comet 45P doesn't pose a threat to Earth. The ball of ice and dust will still be millions of miles from the planet when it makes its close flyby this month.

 

 

This isn't the comet's first pass of the planet. Comet 45P makes a full orbit of Earth every 5.25 years, allowing scientists to track it. 

These "periodic comets" are on predictable paths around the sun and can lend themselves to some good skywatching. (Halley's comet, for instance is also a periodic comet.)

Comet 45P — which like other comets is thought to be a leftover piece of ice and rock from the beginning of the solar system — has been gracing skies for most of December, first appearing on Dec. 15 when it was visible near the star cluster M75.

And the comet isn't the only cosmic sight in the sky on Dec. 31. 

Caption

 

IMAGE: NASA

Mars, which has been visible for most of the month, will look like it's right next to the blue/green tinted Neptune even though the two are millions of miles away from each other in reality. 

Venus, which can masquerade as a bright star at dawn or dusk, will also be visible in the western sky along with Neptune and Mars on New Year's Eve. 

"Through telescopes, rusty red Mars and blue-green Neptune‘s colors contrast beautifully," NASA said.

Quelle: Mashable


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Freitag, 30. Dezember 2016 - 08:00 Uhr

Mars-Chroniken - Curiosity Interner Schmutz kann ein Problem mit Mars-Roverbohrgerät verursachen

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File photo of Curiosity’s drill bit from Feb. 24, 2015. Credit: NASA/JPL-Caltech/MSSS

Engineers suspect a piece of foreign object debris may be intermittently stalling a motor needed to place the Curiosity Mars rover’s drill bit onto rocks, and the robot’s ground team is assessing the source of the potential contamination.

More importantly, Curiosity project manager Jim Erickson said, engineers are spending the holidays crunching data from a series of diagnostic tests conducted in recent weeks to analyze the drill’s behavior and determine a possible fix.

Curiosity is in its second extended mission — the rover’s original primary mission phase ended in 2014 — on the lower flank of Mount Sharp, a three-mile-high (5-kilometer) peak towering over the floor of Gale Crater, the robot’s landing site.

The rover’s drill pulverizes material from inside Martian rocks into powder, and delivers the samples to two of Curiosity’s main science instruments — the Sample Analysis at Mars payload and the Chemistry and Mineralogy package — to look for organic materials and measure mineral content.

Ground controllers believe the drill problem is rooted in a brake on the drill feed mechanism, which is supposed to extend and place the drill bit on the surface of target rocks.

When Curiosity goes in to drill into Martian rocks, the rover extends its robotic arm and two prongs on each side of the drill bit press against the target. The drill feed motor then engages to push the bit onto the rock, then percussive and rotating mechanisms start boring into the target to collect a powder sample.

Erickson told Spaceflight Now that the drill problem, first encountered Dec. 1, has cropped up off and on, but ground controllers have only commanded the motor to move in tiny increments in their testing.

Rover drivers at NASA’s Jet Propulsion Laboratory in Pasadena, California, have also sent Curiosity on short trips and activated shakers inside the drill to test the feed motor’s response to motion, Erickson told Spaceflight Now in JPL’s “Mars yard” facility where engineers test out rover models in simulated Martian terrain.

The shakers are normally used to sort the powder sample acquired by the drill.

Experts believe they found a pattern in the way the drill feed motor behaves over time, Eriskson said, and the pattern observed so far matches what engineers would expect to see if a piece of foreign object debris, or FOD, was embedded somewhere inside the drill.

This view from the wide-angle Hazard Avoidance Camera (Hazcam) on the front of NASA’s Curiosity Mars Rover shows the rover’s drill in position for a mini-drill test on Jan. 13, 2015. Credit: NASA/JPL-Caltech

Erickson said the ground team is not sure of the source of the potential debris. It could be a piece of Martian soil or a pebble that somehow got into the mechanism and is gumming up the drill feed motor, or it might be something carried from Earth.

“It some sense, it probably doesn’t matter,” Erickson said, detailing how engineers are focused, for now, on recovering use of the drill, one of the rover’s primary tools.

He described a “fishbone” diagram used by the investigation team, with arrows splitting off pointing to FOD of terrestrial and Martian origin. Then there’s another split in the fishbone, Erickson said, illustrating two more possibilities, assuming the contamination came from Earth.

“Was it something that the rover carried from Earth from before the launch, or was it generated after the launch?” Erickson asked.

Parts inside the drill may have rubbed together over the last four years since Curiosity’s landing on Mars in August 2012, creating shavings or fragments that are lodged inside the feed motor.

If operating the drill on Mars somehow created the FOD, engineers might be able to change the way they use the instrument, and improve the design of future drills, such as the device in development to fly on NASA’s Mars 2020 rover, a spacecraft largely based on Curiosity’s design and chassis.

Erickson said the rover team is still examining how to resume drilling with Curiosity, and it is too early to declare that engineers can fully correct the problem, or that the issue will prevent future drillings.

It may turn out that the stalled motor remains intermittent, he said, making it a nuisance for ground controllers commanding the rover, but not fatal for the future of the drill.

Engineers originally thought the problem might be rooted in an encoder associated with electrical sensors that tell the rover’s computer how the drill is functioning. In a press conference Dec. 13, Curiosity project scientist Ashwin Vasavada said the problem apparently is with the brake, which is “very much internal to the motor itself.”

Curiosity’s drill works by boring into rock targets with a combination of a percussive, hammering motion and the rotation of the drill bit. Rock powder excavated by the drill goes into a collection chamber, where the material is sifted and sieved for delivery to miniature laboratory instruments on the rover’s science deck.

The target selected for drilling in early December, when the drill feed problem first appeared, was to be the 16th rock drilled by the rover since it landed on Mars in August 2012. It would have been the seventh drilling operation of 2016, according to NASA.

Ground controllers programmed the drill to only use its rotating mechanism on the latest sampling attempt. The percussive mechanism that chisels into rock has had an intermittent electrical short since early 2015, and while that function is still available, officials prefer to avoid using it unless necessary.

Quelle: SN


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