samedi 5 janvier 2019

Best Wishes from around the World 'Beamed' toward New Horizons in the Kuiper Belt













NASA - New Horizons Mission patch.

January 5, 2019

NASA's New Horizons spacecraft flew by a small, distant world in the Kuiper Belt on New Year's Day – the place, officially designated 2014 MU69 and nicknamed Ultima Thule, is 4 billion miles from Earth. No spacecraft has ever explored a world so far away.


Image above: Raw images of the New Horizons MU69 encounter. Image Credits: NASA/JHUAPL/SwRI/Emily Lakdawalla.

Several weeks before that flyby the New Horizons team gave people around the world the opportunity to "beam" their name and a choice of messages, at the speed of light, toward New Horizons and Ultima Thule on flyby day – ¬and 30,547 people ultimately signed on. "Happy 2019!" was the top choice, selected by 8,100 participants, followed by "Keep on Exploring!" sent by 6,800 participants.

Transmitted on New Year's Eve from the satellite communications facility at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland – where New Horizons was built and is operated – the signals carrying the messages reached New Horizons just hours before the flyby, then continued on past Ultima Thule and through the Kuiper Belt.


Image above: Tens of thousands of names and wishes for New Horizons were transmitted to the Kuiper Belt on New Year's Eve from the 60-foot antenna at the satellite communications facility at the Johns Hopkins Applied Physics Laboratory, as NASA's New Horizons spacecraft bore down on its flyby target, Ultima Thule. Image Credit: NASA.

"Never before has the public had an opportunity to have their names and messages across our entire solar system on the historic day of the farthest exploration of worlds in human history," said New Horizons Principal Investigator and "Beam Me" project originator Alan Stern, of the Southwest Research Institute, Boulder, Colorado.

New Horizons spacecraft. Image Credit: NASA

New Horizons' closest approach to Ultima Thule occurred at 12:33 a.m. EST on Jan. 1, when it zipped approximately 2,200 miles (3,500 kilometers) from the object. The spacecraft sent back the first close-up images of its Kuiper Belt target in the following days, confirming that Ultima Thule is a contact binary, and offering tantalizing hints of the science to come.

Related articles:

New Ultima Thule Discoveries from NASA's New Horizons
https://orbiterchspacenews.blogspot.com/2019/01/new-ultima-thule-discoveries-from-nasas.html

New Horizons Mission Reveals Entirely New Kind of World
https://orbiterchspacenews.blogspot.com/2019/01/new-horizons-mission-reveals-entirely.html

New Horizons Successfully Explores Ultima Thule
https://orbiterchspacenews.blogspot.com/2019/01/new-horizons-successfully-explores.html

Live updates and links to mission information are also available on: http://pluto.jhuapl.edu

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: https://www.nasa.gov/newhorizons

Images (mentioned), Text, Credits: NASA/JHUAPL.

Greetings, Orbiter.ch

vendredi 4 janvier 2019

Dragon Departing Station Next Week; Crew Studies Biology













ISS - Expedition 58 Mission patch.

January 4, 2019

The SpaceX Dragon cargo craft is in its final week attached to the International Space Station’s Harmony module. Meanwhile, robotics experts on the ground and the crew aboard the lab are working a wide variety of science activities today.


Image above: The SpaceX Dragon cargo craft is pictured attached to the International Space Station almost 257 miles above Quebec on New Year’s Eve. Image Credit: NASA.

The Dragon space freighter has nearly completed its cargo mission to replenish the orbital laboratory after delivering over 5,600 pounds of science and supplies Dec. 8. Dragon will return to Earth Jan. 10 for retrieval in the Pacific Ocean loaded with completed science experiments and used hardware for analysis.


Image above: Flying over Austral Ocean, seen by EarthCam on ISS, speed: 27'577 Km/h, altitude: 419,72 Km, image captured by Roland Berga (on Earth in Switzerland) from International Space Station (ISS) using ISS-HD Live application with EarthCam's from ISS on January 4, 2019 at 14:25 UTC. Image Credits: Orbiter.ch Aerospace/Roland Berga.

New space exposure experiments are being remotely installed outside the station today using a specialized robotic hand known as Dextre. Also, astronauts Anne McClain and David Saint-Jacques collected biological samples today for stowage and later analysis. The duo then split up for more science work including testing crew brain function and removing science hardware that explores stem cells and other biological processes.

Related links:

Expedition 58: https://www.nasa.gov/mission_pages/station/expeditions/expedition58/index.html

SpaceX Dragon: https://www.nasa.gov/mission_pages/station/structure/launch/spacex.html

Dextre: https://www.nasa.gov/mission_pages/station/structure/elements/special-purpose-dextrous-manipulator

New space exposure experiments: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7929

Brain function: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=979

Stem cells: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7503

Biological processes: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1660

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Text, Credits: NASA/Mark Garcia/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

InSight Places First Instrument on Mars - New Images












NASA - InSight Mission patch.

Jan. 4, 2019


Image above: NASA's InSight lander placed its seismometer on Mars on Dec. 19, 2018. This was the first time a spacecraft robotically placed a seismometer onto the surface of another planet. Image Credits: NASA/JPL-Caltech.

NASA's InSight lander has deployed its first instrument onto the surface of Mars, completing a major mission milestone. New images from the lander show the seismometer on the ground, its copper-colored covering faintly illuminated in the Martian dusk. It looks as if all is calm and all is bright for InSight, heading into the end of the year.

"InSight's timetable of activities on Mars has gone better than we hoped," said InSight Project Manager Tom Hoffman, who is based at NASA's Jet Propulsion Laboratory in Pasadena, California. "Getting the seismometer safely on the ground is an awesome Christmas present." 


Animation above: This set of images from the Instrument Deployment Camera shows NASA's InSight lander placing its first instrument onto the surface of Mars, completing a major mission milestone. Animation Credits: NASA/JPL-Caltech.

The InSight team has been working carefully toward deploying its two dedicated science instruments onto Martian soil since landing on Mars on Nov. 26. Meanwhile, the Rotation and Interior Structure Experiment (RISE), which does not have its own separate instrument, has already begun using InSight's radio connection with Earth to collect preliminary data on the planet’s core. Not enough time has elapsed for scientists to deduce what they want to know — scientists estimate they might have some results starting in about a year.


Animation above: A fish-eye view of NASA's InSight lander deploying its first instrument onto the surface of Mars, taken by the spacecraft's Instrument Context Camera (ICC) on Dec. 19, 2018. Animation Credits: NASA/JPL-Caltech.

To deploy the seismometer (also known as the Seismic Experiment for Interior Structure, or SEIS) and the heat probe (also known as the Heat Flow and Physical Properties Probe, or HP3), engineers first had to verify the robotic arm that picks up and places InSight's instruments onto the Martian surface was working properly. Engineers tested the commands for the lander, making sure a model in the test bed at JPL deployed the instruments exactly as intended. Scientists also had to analyze images of the Martian terrain around the lander to figure out the best places to deploy the instruments.

On Tuesday, Dec. 18, InSight engineers sent up the commands to the spacecraft. On Wednesday, Dec. 19, the seismometer was gently placed onto the ground directly in front of the lander, about as far away as the arm can reach — 5.367 feet, or 1.636 meters, away).

"Seismometer deployment is as important as landing InSight on Mars," said InSight Principal Investigator Bruce Banerdt, also based at JPL. "The seismometer is the highest-priority instrument on InSight: We need it in order to complete about three-quarters of our science objectives."

The seismometer allows scientists to peer into the Martian interior by studying ground motion — also known as marsquakes. Each marsquake acts as a kind of flashbulb that illuminates the structure of the planet's interior. By analyzing how seismic waves pass through the layers of the planet, scientists can deduce the depth and composition of these layers.

"Having the seismometer on the ground is like holding a phone up to your ear," said Philippe Lognonné, principal investigator of SEIS from Institut de Physique du Globe de Paris (IPGP) and Paris Diderot University. "We're thrilled that we're now in the best position to listen to all the seismic waves from below Mars' surface and from its deep interior."

In the coming days, the InSight team will work on leveling the seismometer, which is sitting on ground that is tilted 2 to 3 degrees. The first seismometer science data should begin to flow back to Earth after the seismometer is in the right position.


Image above: This is NASA InSight's first selfie on Mars. It displays the lander's solar panels and deck. On top of the deck are its science instruments, weather sensor booms and UHF antenna. The selfie was taken on Dec. 6, 2018 (Sol 10). Image Credits: NASA/JPL-Caltech.

But engineers and scientists at JPL, the French national space agency Centre National d'Études Spatiales (CNES) and other institutions affiliated with the SEIS team will need several additional weeks to make sure the returned data are as clear as possible. For one thing, they will check and possibly adjust the seismometer's long, wire-lined tether to minimize noise that could travel along it to the seismometer. Then, in early January, engineers expect to command the robotic arm to place the Wind and Thermal Shield over the seismometer to stabilize the environment around the sensors.

Assuming that there are no unexpected issues, the InSight team plans to deploy the heat probe onto the Martian surface by late January. HP3 will be on the east side of the lander's work space, roughly the same distance away from the lander as the seismometer.

For now, though, the team is focusing on getting those first bits of seismic data (however noisy) back from the Martian surface.

"We look forward to popping some Champagne when we start to get data from InSight's seismometer on the ground," Banerdt added. "I have a bottle ready for the occasion."

Animation Credits: NASA/JPL-Caltech

JPL manages InSight for NASA's Science Mission Directorate in Washington. InSight is part of NASA's Discovery Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.

A number of European partners, including CNES and the German Aerospace Center (DLR), support the InSight mission. CNES provided SEIS to NASA, with the principal investigator at IPGP. Significant contributions for SEIS came from IPGP, the Max Planck Institute for Solar System Research in Germany, the Swiss Institute of Technology in Switzerland, Imperial College and Oxford University in the United Kingdom, and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center of the Polish Academy of Sciences and Astronika in Poland. Spain's Centro de Astrobiología supplied the wind sensors.

Related articles:

NASA's InSight Places First Instrument on Mars
https://orbiterchspacenews.blogspot.com/2018/12/nasas-insight-places-first-instrument.html

NASA's InSight Takes Its First Selfie
https://orbiterchspacenews.blogspot.com/2018/12/nasas-insight-takes-its-first-selfie.html

NASA InSight Lander 'Hears' Martian Winds
https://orbiterchspacenews.blogspot.com/2018/12/nasa-insight-lander-hears-martian-winds.html

NASA's Mars InSight Flexes Its Arm
http://orbiterchspacenews.blogspot.com/2018/12/nasas-mars-insight-flexes-its-arm.html

For more information about InSight, visit: https://mars.nasa.gov/insight

Experiment for Interior Structure (SEIS): https://mars.nasa.gov/insight/spacecraft/instruments/seis/

Heat Flow and Physical Properties Probe (HP3): https://mars.nasa.gov/insight/mission/instruments/hp3/

Images (mentioned), Animations (mentioned), Text, Credits: NASA/Jon Nelson/JPL/Jia-Rui Cook/Andrew Good.

Best regards, Orbiter.ch

"Small step for the rover, big step for China"













CLEP - China Lunar Exploration Program logo.

Jan. 4, 2019


Image above: China's Yutu 2 Lunar Rover Leaves First Ever Footprint on Moon's Far Side. Image Credits: CNSA/CLEP.

After a historic lunar landing on the far side of the moon, the Chinese space agency announced that its exploration by a robot had begun.

A small Chinese motorized robot has begun to explore the hidden face of the moon, the Chinese space agency said Friday after the historic moon landing of its Chang'e-4 exploration module, hailing a "big step for the Chinese people."

Chang’e-4 Yutu-2 rover starts exploring the Von Karman Crater

Video above: The Chang’e-4 rover, named Yutu-2 (玉兔二号, Jade Rabbit-2), was deployed onto the surface of the Von Karman Crater, on 3 January 2019, at 14:22 UTC (22:22 Beijing time). The Von Karman Crater is located in the Aitken Basin, in the South Pole region on the far side of the Moon. China’s Chang’e-4 (嫦娥四号) lunar mission landed in the crater on 3 January 2019, at 02:26 UTC (10:26 Beijing time). Communications with Earth are provided by the relay satellite Queqiao (鹊桥, Magpie Bridge). Video Credits: China Central Television (CCTV)/China National Space Administration (CNSA)/SciNews.

The Yutu-2 rover surveyed the lunar surface on Thursday at 10:22 am Beijing time (1422 GMT), 12 hours after China achieved the first ever moon landing of a spacecraft on the dark side. of the Moon, the agency said.


Animation above:  Yutu-2 rover leave Chang’e-4 lander and starts exploring the Von Karman Crater. Animation Credits: CNSA/CLEP/Orbiter.ch Aerospace/Roland Berga.

The latter published a photo taken by the Chang'e-4 module (named after the goddess of the moon in Chinese mythology) and showing traces of the small radio-controlled vehicle as it left the spacecraft. The Chinese agency did not specify the distance traveled by the robot.

"Even though it was just a small step for the rover, I think it's a big step for the Chinese people," said Wu Weiren, chief engineer of the Chinese program. lunar exploration, in an interview with state television CCTV.

Chang'e 4 lander-rover relayed back via satellite relay.Image Credits: CASC/CNSA

An allusion to the famous phrase ("A small step for man, a big step for humanity") pronounced by the American astronaut Neil Armstrong, the first man to have walked on the Moon, in 1969.

Unknown territory

This is the second time that the Asian giant sends a machine to explore the moon after the small motorized robot Yutu ("Jade Bunny") in 2013. He remained active for 31 months, on the visible side of the star.


Image above: Artist's view of China's Yutu 2 Lunar Rover Leaves lander, first roll on the Moon far side. Image Credits: CASC/CNSA.

Unlike this face closest to Earth, which is still facing our planet, no probe or exploration module had yet touched the ground on the other side. This one, mountainous and uneven, is strewn with craters.

China invests billions in its space program, led by the military. It places satellites in orbit, on its behalf (earth observation, telecommunications, Beidou geolocation system) or for other countries. She also hopes to send humans to the moon.

Related articles:

Chang'e 4 spacecraft sends images after landing on far side of the Moon
https://orbiterchspacenews.blogspot.com/2019/01/change-4-spacecraft-sends-images-after.html

Chang'e-4 Probe Enters Lunar Orbit
https://orbiterchspacenews.blogspot.com/2018/12/change-4-probe-enters-lunar-orbit.html

China launches lunar rover in historic mission to the dark side of the moon
https://orbiterchspacenews.blogspot.com/2018/12/china-launches-lunar-rover-in-historic.html

For more information about China Aerospace Science and Technology Corporation (CASC), visit: http://english.spacechina.com/n16421/index.html

For more information about China National Space Administration (CNSA), visit: http://www.cnsa.gov.cn/

Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits:  NXP/AFP/CNSA/CASC/CLEP/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

jeudi 3 janvier 2019

New Ultima Thule Discoveries from NASA's New Horizons













NASA - New Horizons Mission patch.

January 3, 2019


Image above: Illustration of NASA’s New Horizons spacecraft encountering 2014 MU69 – nicknamed “Ultima Thule” – a Kuiper Belt object that orbits one billion miles beyond Pluto. Set for New Year’s 2019, New Horizons’ exploration of Ultima is the farthest space probe flyby in history. Image Credits: NASA/JHUAPL/SwRI.

Ultima Thule in 3D

Data from NASA's New Horizons spacecraft, which explored Kuiper Belt object Ultima Thule earlier this week, is yielding scientific discoveries daily. Among the findings made by the mission science team in the past day are:

- Initial data analysis has found no evidence of rings or satellites larger than one mile in diameter orbiting Ultima Thule.

- Data analysis has also not yet found any evidence of an atmosphere.

- The color of Ultima Thule matches the color of similar worlds in the Kuiper Belt, as determined by telescopic measurements.

- The two lobes of Ultima Thule — the first Kuiper Belt contact binary visited — are nearly identical in color. This matches what we know about binary systems which haven't come into contact with each other, but rather orbit around a shared point of gravity.

"The first exploration of a small Kuiper Belt object and the most distant exploration of any world in history is now history, but almost all of the data analysis lies in the future," said Alan Stern of the Southwest Research Institute in Boulder, Colorado.


Image above: The New Horizons science team created the first stereo image pair of Ultima Thule. This image can be viewed with stereo glasses to reveal the Kuiper Belt object's three-dimensional shape. The images that created the stereo pair were taken by the Long-Range Reconnaissance Imager (LORRI) at 4:23 and 5:01 Universal Time on January 1, 2019 from respective ranges of 38,000 miles (61,000 kilometers) and 17,000 miles (28,000 kilometers), with respective original scales of 1017 feet (310 meters) and 459 feet (140 meters) per pixel. Image Credits: NASA/JHUAPL/SwRI.

Data transmission from New Horizons will pause for about a week while the spacecraft passes behind the sun as seen from here on Earth. Data transmission resumes Jan. 10, starting a 20-month download of the spacecraft's remaining scientific treasures.

"Those of us on the science team can't wait to begin to start digging into that treasure trove," said Stern. New Horizons completed the farthest flyby in history when it came within about 2,200 miles (3,500 kilometers) of Ultima Thule at 12:33 a.m. EST on Jan. 1, zooming past the object at more than 32,000 miles (51,000 kilometers) per hour.


Animation above: In this animated GIF of Kuiper Belt object Ultima Thule made from two images taken 38 minutes apart, the "Thule" lobe is closest to the New Horizons spacecraft. As Ultima Thule is seen to rotate, hints of the topography can be perceived. The images were taken by the Long-Range Reconnaissance Imager (LORRI) at 4:23 and 5:01 Universal Time on January 1, 2019 from respective ranges of 38,000 miles (61,000 kilometers) and 17,000 miles (28,000 kilometers), with respective original scales of 1017 feet (310 meters) and 459 feet (140 meters) per pixel. Animation Credits: NASA/JHUAPL/SwRI.

The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, designed, built and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Related articles:

New Horizons Mission Reveals Entirely New Kind of World
https://orbiterchspacenews.blogspot.com/2019/01/new-horizons-mission-reveals-entirely.html

New Horizons Successfully Explores Ultima Thule
https://orbiterchspacenews.blogspot.com/2019/01/new-horizons-successfully-explores.html

Live updates and links to mission information are also available on: http://pluto.jhuapl.edu

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: https://www.nasa.gov/newhorizons

Images (mentioned), Animation (mentioned), Video, Text, Credits: NASA/JHUAPL.

Best regards, Orbiter.ch

Chang'e 4 spacecraft sends images after landing on far side of the Moon













China Lunar Exploration Program logo.

Jan. 3, 2019


Image above: An image of the Moon's far side taken by the Chang'e-4 probe.  Photo: The first image of the Moon's far side, taken by China's Chang'e-4 probe. (AP: China National Space Administration/Xinhua News Agency).

A Chinese spacecraft has made the first landing on the far side of the Moon, sending back images of a crater in the latest achievement for the country's growing space program.

Chang’e-4 lands on the Moon and sends back first images

China’s Chang'e-4 lunar mission (lander and rover) landed in the Von Karman Crater, located in the Aitken Basin, in the South Pole region on the far side of the Moon, on 3 January 2019, at 02:26 UTC (10:26 Beijing time). The Chang’e-4 lunar mission was launched by a Long March-3B rocket from the Xichang Satellite Launch Center, Sichuan Province, southwest China, on 7 December 2018, at 18:23 UTC (8 December at 02:23 local time). Video Credit: China Central Television (CCTV)/China National Space Administration (CNSA)/Music: Moonlight Sonata by Beethoven courtesy of YouTube Audio Library.

The Chang'e-4 probe successfully performed the first soft landing on the Moon's far side on Thursday, the Chinese National Space Agency said. One image, taken from the south side of the landing site, was relayed back via a relay satellite, according to state-owned television network CGTN.

Black and white images taken by the probe before and after its landing where also shared by Chinese news agencies. It is the first time a soft landing has been performed on the Moon's far side — also known as the dark side because it faces away from Earth and remains comparatively unknown — due to challenges relaying signals.

Chang'e 4 is a lander-rover combination and will explore both above and below the lunar surface.


Image above: An image taken by China's Chang'e-4 spacecraft after its landing on the far side of the moon. Photo Credits: (AP: China National Space Administration/Xinhua News Agency).

Some of the experiments aboard will investigate the Moon's potential to support future space travelers. One of those experiments is a biosphere project, which includes silkworm eggs, thale cress and potatoes seeds.

If it goes to plan, the ecosystem would be self-sustaining, with the silkworms germinating the potatoes and popping out caterpillars. These would in turn produce carbon dioxide, helping the plants grow as a food source.

Artist's view of Chang'e-4 landed on the dark side of the Moon. Image Credits: CASC/CNSA

Because the far side faces away from Earth, it is also shielded from radio transmissions — making it the perfect place from which to study the universe. The mission is part of China's ambitious push to explore the Moon's resources and potential as a space base.

China landed its Yutu, or 'Jade Rabbit' rover on the Moon five years ago and plans to have Chang'e 5 return to earth with samples — the first time that will have been done since 1976. A crewed lunar mission is also under consideration.

The Moon's not-so-dark side

While in popular culture the far side of the Moon is often called the "dark side", the far side is not dark in the sense that it does get exposed to sunlight.

It is known as the far side because only the near side of the Moon can be seen from Earth, as the Moon takes the same time to spin on its axis as it takes to complete one full orbit.

Chang'e 4 lander-rover relayed back via a relay satellite.Image Credits: CASC/CNSA

The far side has been mapped by several orbiting craft over the years.

The dominant feature is the 2,500km-wide South Pole-Aitken basin, the Moon's oldest and deepest crater. Scientists are particularly interested in the geology of the basin as it may help explain how the Moon formed.

Related articles:

Chang'e-4 Probe Enters Lunar Orbit
https://orbiterchspacenews.blogspot.com/2018/12/change-4-probe-enters-lunar-orbit.html

China launches lunar rover in historic mission to the dark side of the moon
https://orbiterchspacenews.blogspot.com/2018/12/china-launches-lunar-rover-in-historic.html

For more information about China Aerospace Science and Technology Corporation (CASC), visit: http://english.spacechina.com/n16421/index.html

For more information about China National Space Administration (CNSA), visit: http://www.cnsa.gov.cn/

Images (mentioned), Video (mentioned), Text, Credits: CASC/CNSA/AP/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

mercredi 2 janvier 2019

New Horizons Mission Reveals Entirely New Kind of World













NASA - New Horizons Mission patch.

January 2, 2019

Images of the Kuiper Belt object Ultima Thule unveil the very first stages of solar system's history


Image above: This image taken by the Long-Range Reconnaissance Imager (LORRI) is the most detailed of Ultima Thule returned so far by the New Horizons spacecraft. It was taken at 5:01 Universal Time on January 1, 2019, just 30 minutes before closest approach from a range of 18,000 miles (28,000 kilometers), with an original scale of 459 feet (140 meters) per pixel. Image Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

Scientists from NASA's New Horizons mission released the first detailed images of the most distant object ever explored — the Kuiper Belt object nicknamed Ultima Thule. Its remarkable appearance, unlike anything we've seen before, illuminates the processes that built the planets four and a half billion years ago.

"This flyby is a historic achievement," said New Horizons Principal Investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado. "Never before has any spacecraft team tracked down such a small body at such high speed so far away in the abyss of space. New Horizons has set a new bar for state-of-the-art spacecraft navigation."


Images above: The first color image of Ultima Thule, taken at a distance of 85,000 miles (137,000 kilometers) at 4:08 Universal Time on January 1, 2019, highlights its reddish surface. At left is an enhanced color image taken by the Multispectral Visible Imaging Camera (MVIC), produced by combining the near infrared, red and blue channels. The center image taken by the Long-Range Reconnaissance Imager (LORRI) has a higher spatial resolution than MVIC by approximately a factor of five. At right, the color has been overlaid onto the LORRI image to show the color uniformity of the Ultima and Thule lobes. Note the reduced red coloring at the neck of the object. Images Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

The new images — taken from as close as 17,000 miles (27,000 kilometers) on approach — revealed Ultima Thule as a "contact binary," consisting of two connected spheres. End to end, the world measures 19 miles (31 kilometers) in length. The team has dubbed the larger sphere "Ultima" (12 miles/19 kilometers across) and the smaller sphere "Thule" (9 miles/14 kilometers across).


Image above: This image taken by the Long-Range Reconnaissance Imager (LORRI) is the most detailed of Ultima Thule returned so far by the New Horizons spacecraft. It was taken at 5:01 Universal Time on January 1, 2019, just 30 minutes before closest approach from a range of 18,000 miles (28,000 kilometers), with an original scale of 459 feet (140 meters) per pixel. Image Credits: NASA/JHUAPL/SwRI.

The team says that the two spheres likely joined as early as 99 percent of the way back to the formation of the solar system, colliding no faster than two cars in a fender-bender.

"New Horizons is like a time machine, taking us back to the birth of the solar system. We are seeing a physical representation of the beginning of planetary formation, frozen in time," said Jeff Moore, New Horizons Geology and Geophysics team lead. "Studying Ultima Thule is helping us understand how planets form — both those in our own solar system and those orbiting other stars in our galaxy."

Data from the New Year's Day flyby will continue to arrive over the next weeks and months, with much higher resolution images yet to come.


Image above: Illustration of NASA’s New Horizons spacecraft encountering 2014 MU69 – nicknamed “Ultima Thule” – a Kuiper Belt object that orbits one billion miles beyond Pluto. Set for New Year’s 2019, New Horizons’ exploration of Ultima is the farthest space probe flyby in history. Image Credits: NASA/JHUAPL/SwRI.

"In the coming months, New Horizons will transmit dozens of data sets to Earth, and we'll write new chapters in the story of Ultima Thule — and the solar system," said Helene Winters, New Horizons Project Manager.

The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, designed, built and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Related article:

New Horizons Successfully Explores Ultima Thule
https://orbiterchspacenews.blogspot.com/2019/01/new-horizons-successfully-explores.html

Live updates and links to mission information are also available on: http://pluto.jhuapl.edu

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: https://www.nasa.gov/newhorizons

Images (mentioned), Text, Credits: NASA/JHUAPL.

Best regards, Orbiter.ch

OSIRIS-REx Spacecraft Enters Close Orbit Around Bennu, Breaking Record












NASA - OSIRIS-REx Mission patch.

Jan. 2, 2019

On December 31, 2018 - At 2:43 p.m. EST on December 31, while many on Earth prepared to welcome the New Year, NASA’s OSIRIS-REx spacecraft, 70 million miles (110 million kilometers) away, carried out a single, eight-second burn of its thrusters – and broke a space exploration record. The spacecraft entered into orbit around the asteroid Bennu, and made Bennu the smallest object ever to be orbited by a spacecraft.


Image above: On Dec. 31, 2018, NASA’s OSIRIS-REx spacecraft went into orbit around asteroid Bennu for the first time. Image Credit: NASA.

“The team continued our long string of successes by executing the orbit-insertion maneuver perfectly,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. “With the navigation campaign coming to an end, we are looking forward to the scientific mapping and sample site selection phase of the mission.”

Lauretta, along with his team, spent the last day of 2018 with his feet planted on Earth, but his mind focused on space. “Entering orbit around Bennu is an amazing accomplishment that our team has been planning for years,” Lauretta said.

Inching around the asteroid at a snail’s pace, OSIRIS-REx’s first orbit marks a leap for humankind. Never before has a spacecraft from Earth circled so close to such a small space object – one with barely enough gravity to keep a vehicle in a stable orbit.

Now, the spacecraft will circle Bennu about a mile (1.75 kilometers) from its center, closer than any other spacecraft has come to its celestial object of study. (Previously the closest orbit of a planetary body was in May 2016, when the Rosetta spacecraft orbited about four miles (seven kilometers) from the center of the comet 67P/Churyumov-Gerasimenko.) The comfortable distance is necessary to keep the spacecraft locked to Bennu, which has a gravity force only 5-millionths as strong as Earth’s. The spacecraft is scheduled to orbit Bennu through mid-February at a leisurely 62 hours per orbit.

Now that the OSIRIS-REx spacecraft is closer to Bennu, physical details about the asteroid will leap into sharper focus, and the spacecraft’s tour of this rubble pile of primordial debris will become increasingly detailed and focused.

“Our orbit design is highly dependent on Bennu’s physical properties, such as its mass and gravity field, which we didn’t know before we arrived,” said OSIRIS-REx’s flight dynamics system manager Mike Moreau, who is based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

“Up until now, we had to account for a wide variety of possible scenarios in our computer simulations to make sure we could safely navigate the spacecraft so close to Bennu. As the team learned more about the asteroid, we incorporated new information to hone in on the final orbit design,” he said.

The simulations have played a critical role. The OSIRIS-REx mission, after all, was designed based on complex computer programs that predicted — quite accurately, as it turns out — the properties of Bennu and how the spacecraft’s trajectory would behave. This diligent preparation allowed the team to navigate the vehicle safely to Bennu in December and put some questions to rest (there are, indeed, signs of ancient water preserved in Bennu’s rocks) and to fly over its poles and equator in a preliminary survey that led to some surprises (Bennu has many large boulders).

Having completed the preliminary survey of Bennu with a flyby of its south pole on December 16, the spacecraft moved to a safe 31 miles (50 kilometers) away from the asteroid to give the navigation team a chance to regroup and prepare for orbit insertion. Next, Lockheed Martin engineers programmed the spacecraft to begin moving back to a position about nine miles (15 kilometers) over Bennu’s north pole to prepare for three burns of its thrusters over the course of 10 days that would place the spacecraft into orbit.

OSIRIS-REx Begins Orbiting Asteroid Bennu

Even though OSIRIS-REx is in the most stable orbit possible, Bennu’s gravitational pull is so tenuous that keeping the spacecraft safe will require occasional adjustments, said Dan Wibben, OSIRIS-REx maneuver and trajectory design lead at KinetX Aerospace in Simi Valley, California.

“The gravity of Bennu is so small, forces like solar radiation and thermal pressure from Bennu’s surface become much more relevant and can push the spacecraft around in its orbit much more than if it were orbiting around Earth or Mars, where gravity is by far the most dominant force,” he said.

The OSIRIS-REx navigation team will use “trim” maneuvers to slightly thrust the spacecraft in one direction or another to correct its orbit and counter these small forces. If the spacecraft drifts away from Bennu, or some other problem forces it into safe mode, it has been programmed to fly away from the asteroid to stay safe from impact.

“It’s simple logic: always burn toward the Sun if something goes wrong,” said Coralie Adam, OSIRIS-REx lead optical navigation engineer at KinetX. Engineers can navigate the spacecraft back into orbit if it drifts away, Adam said, though that’s unlikely to happen.

The navigation and spacecraft operations teams are focused on the first orbital phase. Their primary goal is to transition away from star-based navigation, which allowed the team to locate the spacecraft based on pictures of the star formations around it taken by the cameras onboard. Navigators use methods like this since there is no GPS in deep space and we can’t see the spacecraft from Earth-based telescopes. From this point forward, though, the OSIRIS-REx team will rely on landmarks on Bennu’s surface to track OSIRIS-REx, a more precise technique that will ultimately guide them to a sample-collection site clear of boulders and large rocks, said Adam.

“After conducting a global imaging and mapping campaign during our recent preliminary survey phase, the science team has created 3-D models of Bennu’s terrain that we’re going to begin using for navigation around the asteroid,” she said.

Another critical objective of this orbital phase, Adam said, is to get a better handle on Bennu’s mass and gravity, features that will influence the planning of the rest of the mission, notably the short touchdown on the surface for sample collection in 2020. In the case of Bennu, scientists can only measure these features by getting OSIRIS-REx very close to the surface to see how its trajectory bends from Bennu’s gravitational pull.

“The Orbital A phase will help improve our detailed models for Bennu’s gravity field, thermal properties, orientation, and spin rate,” said Wibben. “This, in turn, will allow us to refine our trajectory designs for the even more challenging flight activities we will perform in 2019.”

The December 31 maneuver to place the spacecraft into orbit about Bennu is the first of many exciting navigation activities planned for the mission. The OSIRIS-REx team will resume science operations in late February. At that point, the spacecraft will perform a series of close flybys of Bennu for several months to take high-resolution images of every square inch of the asteroid to help select a sampling site. During the summer of 2020, the spacecraft will briefly touch the surface of Bennu to retrieve a sample. The OSIRIS-REx mission is scheduled to deliver the sample to Earth in September 2023.

Goddard provides overall mission management, systems engineering and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama for the agency’s Science Mission Directorate in Washington.

Related article:

Planetary Defense: Tonight begin the Bennu Experiment
https://orbiterchspacenews.blogspot.com/2018/12/planetary-defense-tonight-begin-bennu.html

OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security Regolith Explorer): http://www.nasa.gov/mission_pages/osiris-rex/index.html

Image (mentioned), Video (OSIRIS-REx Mission), Text, Credits: NASA/Erin Morton/GSFC/Lonnie Shekhtman.

Greetings, Orbiter.ch

mardi 1 janvier 2019

New Horizons Successfully Explores Ultima Thule













NASA - New Horizons Mission patch.

January 1, 2019

NASA Spacecraft Reaches Most Distant Target in History

 
NASA's New Horizons spacecraft flew past Ultima Thule in the early hours of New Year's Day, ushering in the era of exploration from the enigmatic Kuiper Belt, a region of primordial objects that holds keys to understanding the origins of the solar system.


Image above: At left is a composite of two images taken by New Horizons' high-resolution Long-Range Reconnaissance Imager (LORRI), which provides the best indication of Ultima Thule's size and shape so far. Preliminary measurements of this Kuiper Belt object suggest it is approximately 20 miles long by 10 miles wide (32 kilometers by 16 kilometers). An artist's impression at right illustrates one possible appearance of Ultima Thule, based on the actual image at left. The direction of Ultima's spin axis is indicated by the arrows. Image Credits: NASA/JHUAPL/SwRI; sketch courtesy of James Tuttle Keane.

"Congratulations to NASA's New Horizons team, Johns Hopkins Applied Physics Laboratory and the Southwest Research Institute for making history yet again. In addition to being the first to explore Pluto, today New Horizons flew by the most distant object ever visited by a spacecraft and became the first to directly explore an object that holds remnants from the birth of our solar system," said NASA Administrator Jim Bridenstine. "This is what leadership in space exploration is all about."

Signals confirming the spacecraft is healthy and had filled its digital recorders with science data on Ultima Thule reached the mission operations center at the Johns Hopkins Applied Physics Laboratory (APL) today at 10:29 a.m. EST, almost exactly 10 hours after New Horizons' closest approach to the object.

Where is New Horizons? Image Credit: JHUAPL

"New Horizons performed as planned today, conducting the farthest exploration of any world in history — 4 billion miles from the Sun," said Principal Investigator Alan Stern, of the Southwest Research Institute in Boulder, Colorado. "The data we have look fantastic and we're already learning about Ultima from up close. From here out the data will just get better and better!"

Images taken during the spacecraft's approach — which brought New Horizons to within just 2,200 miles (3,500 kilometers) of Ultima at 12:33 a.m. EST — revealed that the Kuiper Belt object may have a shape similar to a bowling pin, spinning end over end, with dimensions of approximately 20 by 10 miles (32 by 16 kilometers). Another possibility is Ultima could be two objects orbiting each other. Flyby data have already solved one of Ultima's mysteries, showing that the Kuiper Belt object is spinning like a propeller with the axis pointing approximately toward New Horizons. This explains why, in earlier images taken before Ultima was resolved, its brightness didn't appear to vary as it rotated. The team has still not determined the rotation period.

As the science data began its initial return to Earth, mission team members and leadership reveled in the excitement of the first exploration of this distant region of space.

"New Horizons holds a dear place in our hearts as an intrepid and persistent little explorer, as well as a great photographer," said Johns Hopkins Applied Physics Laboratory Director Ralph Semmel. "This flyby marks a first for all of us — APL, NASA, the nation and the world — and it is a great credit to the bold team of scientists and engineers who brought us to this point."


Animation above: This sequence of three images, received on Dec. 31, 2018, and taken by the LORRI camera onboard New Horizons at 70 and 85 minutes apart illustrates the rotation of Ultima Thule. Animation Credits: NASA/JHUAPL/SwRI.

"Reaching Ultima Thule from 4 billion miles away is an incredible achievement. This is exploration at its finest," said Adam L. Hamilton, president and CEO of the Southwest Research Institute in San Antonio. "Kudos to the science team and mission partners for starting the textbooks on Pluto and the Kuiper Belt. We're looking forward to seeing the next chapter."

The New Horizons spacecraft will continue downloading images and other data in the days and months ahead, completing the return of all science data over the next 20 months. When New Horizons launched in January 2006, George W. Bush was in the White House, Twitter had just been launched and Time Magazine's Person of the Year was "you — all the worldwide web users." Nine years into its journey, the spacecraft began its exploration of the Kuiper Belt with a flyby of Pluto and its moons. Almost 13 years after the launch, the spacecraft will continue its exploration of the Kuiper Belt until at least 2021. Team members plan to propose more Kuiper Belt exploration.


Images above: Just over 24 hours before its closest approach to Kuiper Belt object Ultima Thule, the New Horizons spacecraft has sent back the first images that begin to reveal Ultima's shape. The original images have a pixel size of 6 miles (10 kilometers), not much smaller than Ultima's estimated size of 20 miles (30 kilometers), so Ultima is only about 3 pixels across (left panel). However, image-sharpening techniques combining multiple images show that it is elongated, perhaps twice as long as it is wide (right panel). This shape roughly matches the outline of Ultima's shadow that was seen in observations of the object passing in front of a star made from Argentina in 2017 and Senegal in 2018. Image Credits: Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.

The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, designed, built and operates the New Horizons spacecraft, and manages the mission for NASA's Science Mission Directorate. The Southwest Research Institute, based in San Antonio, leads the science team, payload operations and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Related article:

Hubble Paved the Way for the New Horizons Mission to Pluto and Ultima Thule
https://orbiterchspacenews.blogspot.com/2018/12/hubble-paved-way-for-new-horizons.html

Live updates and links to mission information are also available on: http://pluto.jhuapl.edu

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: https://www.nasa.gov/newhorizons

Images (mentioned), Animation (mentioned), Banner, Text, Credits: NASA/JHUAPL.

Happy New Year 2019! Best regards, Orbiter.ch

lundi 31 décembre 2018

Planetary Defense: Tonight begin the Bennu Experiment












NASA - OSIRIS-REx Mission patch.

Dec. 31, 2018

On Dec. 3, after traveling billions of kilometers from Earth, NASA's OSIRIS-REx spacecraft reached its target, Bennu, and kicked off a nearly two-year, up-close investigation of the asteroid. It will inspect nearly every square inch of this ancient clump of rubble left over from the formation of our solar system. Ultimately, the spacecraft will pick up a sample of pebbles and dust from Bennu's surface and deliver it to Earth in 2023.


Image above: This artist's concept shows the Origins Spectral Interpretation Resource Identification Security - Regolith Explorer (OSIRIS-REx) spacecraft contacting the asteroid Bennu with the Touch-And-Go Sample Arm Mechanism or TAGSAM. The mission aims to return a sample of Bennu's surface coating to Earth for study as well as return detailed information about the asteroid and it's trajectory. Image Credits: NASA's Goddard Space Flight Center.

The spacecraft’s first orbital insertion is scheduled for Dec. 31 (today), and OSIRIS-REx will remain in orbit until mid-February 2019, when it exits to initiate another series of flybys for the next survey phase. During the first orbital phase, the spacecraft will orbit the asteroid at a range of 0.9 miles (1.4 km) to 1.24 miles (2.0 km) from the center of Bennu — setting new records for the smallest body ever orbited by a spacecraft and the closest orbit of a planetary body by any spacecraft.

Generations of planetary scientists will get to study pieces of the primitive materials that formed our cosmic neighborhood and to better understand the role asteroids may have played in delivering life-forming compounds to planets and moons.

But it's not just history that the mission to Bennu will help uncover. Scientists studying the rock through OSIRIS-REx's instruments in space will also shape our future. As they collect the most detailed information yet about the forces that move asteroids, experts from NASA's Planetary Defense Coordination Office, who are responsible for detecting potentially hazardous asteroids, will improve their predictions of which ones could be on a crash-course with our planet.

Here is how the OSIRIS-REx mission will support this work:

How scientists predict Bennu's whereabouts

About a third of a mile, or half a kilometer, wide, Bennu is large enough to reach Earth's surface; many smaller space objects, in contrast, burn up in our atmosphere. If it impacted Earth, Bennu would cause widespread damage. Asteroid experts at the Center for Near-Earth Object Studies (CNEOS) at NASA's Jet Propulsion Laboratory in Pasadena, California, project that Bennu will come close enough to Earth over the next century to pose a 1 in 2,700 chance of impacting it between 2175 and 2196. Put another way, those odds mean there is a 99.963 percent chance the asteroid will miss the Earth. Even so, astronomers want to know exactly where Bennu is located at all times.


Animation above: This series of images taken by the OSIRIS-REx spacecraft shows Bennu in one full rotation from a distance of around 50 miles (80 km). The spacecraft’s PolyCam camera obtained the thirty-six 2.2-millisecond frames over a period of four hours and 18 minutes. Animation Credits: NASA's Goddard Space Flight Center/University of Arizona.

Astronomers have estimated Bennu's future trajectory after observing it several times since it was discovered in 1999. They've turned their optical, infrared and radio telescopes toward the asteroid every time it came close enough to Earth, about every six years, to deduce features such as its shape, rotation rate and trajectory.

"We know within a few kilometers where Bennu is right now," said Steven Chesley, senior research scientist at CNEOSand an OSIRIS-REx team member whose job it is to predict Bennu's future trajectory.

Why Bennu's future trajectory predictions get fuzzy

Scientists have estimated Bennu's trajectory around the Sun far into the future. Their predictions are informed by ground observations and mathematical calculations that account for the gravitational nudging of Bennu by the Sun, the Moon, planets and other asteroids, plus non-gravitational factors.

Given these parameters, astronomers can predict the next four exact dates (in September of 2054, 2060, 2080 and 2135) that Bennu will come within 7.5 million kilometers (5 million miles or .05 astronomical units) of Earth. That's close enough that Earth's gravity will slightly bend Bennu's orbital path as it passes by. As a result, the uncertainty about where the asteroid will be each time it loops back around the Sun will grow, causing predictions about Bennu's future orbit to become increasingly hazy after 2060.

In 2060, Bennu will pass Earth at about twice the distance from here to the Moon. But it could pass at any point in a 30-kilometer (19-mile) window of space. A very small difference in position within that window will get magnified enormously in future orbits and make it increasingly hard to predict Bennu's trajectory.

As a result, when this asteroid comes back near Earth in 2080, according to Chesley's calculations, the best window we can get on its whereabouts is 14,000 kilometers (nearly 9,000 miles) wide. By 2135, when Bennu's shifted orbit is expected to bring it closer than the Moon, its flyby window grows wider, to 160,000 kilometers (nearly 100,000 miles). This will be Bennu's closest approach to Earth over the five centuries for which we have reliable calculations.

"Right now, Bennu has the best orbit of any asteroid in our database," Chesley said. "And yet, after that encounter in 2135, we really can't say exactly where it is headed."


Animation above: This picture shows the OSIRIS-REx spacecraft’s view of Bennu during the final phase of its journey to the asteroid. From Aug. 17 through Nov. 27 the spacecraft’s PolyCam camera imaged Bennu almost daily as the spacecraft traveled 1.4 million miles (2.2 million km) toward the asteroid. The final images were obtained from a distance of around 40 miles (65 km). During this period, OSIRIS-REx completed four maneuvers slowing the spacecraft’s velocity from approximately 1,100 mph (491 m/sec) to 0.10 mph (0.04 m/sec) relative to Bennu, which resulted in the slower approach speed at the end of the video. Animation Credits: NASA's Goddard Space Flight Center/University of Arizona.

There's another phenomenon nudging Bennu's orbit and muddying future impact projections. It's called the Yarkovsky effect. Having nothing to do with gravity, the Yarkovsky effect sways Bennu's orbit because of heat from the Sun.

"There are a lot of factors that might affect the predictability of Bennu's trajectory in the future, but most of them are relatively small," says William Bottke, an asteroid expert at the Southwest Research Institute in Boulder, Colorado, and a participating scientist on the OSIRIS-REx mission. "The one that's most sizeable is Yarkvovsky."

This heat nudge was named after the Polish civil engineer who first described it in 1901: Ivan Osipovich Yarkovsky. He suggested thatsunlight warms one side of a small, dark asteroid and some hours later the heat radiates away as the asteroid rotates its hot side into cold darkness. This thrusts the rock pile a bit, either toward the Sun or away from it, depending on the direction of its rotation.

In Bennu's case, astronomers have calculated that the Yarkovsky effect has shifted its orbit about 284 meters (0.18 miles) per year toward the Sunsince 1999. In fact, it helped deliver Bennu to our part of the solar system, in the first place, from the asteroid belt between Mars and Jupiter over billions of years. Now, Yarkovsky is complicating our efforts to make predictions about Bennu's path relative to Earth.

Getting face-to-face with the asteroid will help

The OSIRIS-REx spacecraft will use its suite of instruments to transmit radio tracking signals and capture optical images of Bennu that will help NASA scientists determine its precise position in the solar system and its exact orbital path. Combined with existing, ground-based observations, the space measurements will help clarify how Bennu's orbit is changing over time.

Additionally, astronomers will get to test their understanding of the Yarkovksy effect on a real-life asteroid for the first time. They will instruct the spacecraft to follow Bennu in its orbit about the Sun for about two years to see whether it's moving along an expected path based on gravity and Yarkovsky theories. Any differences between the predictions and reality could be used to refine models of the Yarkovsky effect.

But even more significant to understanding Yarkovsky better will be the thermal measurements of Bennu. During its mission, OSIRIS-REx will track how much solar heat radiates off the asteroid, and where on the surface it's coming from—data that will help confirm and refine calculations of the Yarkovsky effect on asteroids.

The spacecraft also will address some open questions about the Yarkovsky theory. One of them, said Chesley, is how do boulders and craters on the surface of an asteroid change the way photons scatter off of it as it cools, carrying away momentum from the hotter side and thereby nudging the asteroid in the opposite direction? OSIRIS-REx will help scientists understand by mapping the rockiness of Bennu's surface.

"We know surface roughness is going to affect the Yarkovsky effect; we have models" said Chesley. "But the models are speculative. No one has been able to test them."

After the OSIRIS-REx mission, Chesley said, NASA's trajectory projections for Bennu will be about 60 times better than they are now.

Related article:

NASA’s Newly Arrived OSIRIS-REx Spacecraft Already Discovers Water on Asteroid
http://orbiterchspacenews.blogspot.com/2018/12/nasas-newly-arrived-osiris-rex.html

Related links:

Center for Near-Earth Object Studies (CNEOS): https://cneos.jpl.nasa.gov/

OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security Regolith Explorer): http://www.nasa.gov/mission_pages/osiris-rex/index.html

Image (mentioned), Animations (mentioned), Text, Credits: NASA/Dwayne Brown/JoAnna Wendel/Tricia Talbert/JPL/DC Agle/Goddard Space Flight Center, by Lonnie Shekhtman.

Happy New Year, Orbiter.ch

Hubble Paved the Way for the New Horizons Mission to Pluto and Ultima Thule













NASA -  New Horizons Mission patch.

December 31, 2018

New Year's Ultima Thule encounter

Years before a team of researchers proposed a mission called New Horizons to explore the dwarf planet Pluto, NASA's Hubble Space Telescope had already made initial observations of the world at the dim outer fringes of our celestial neighborhood. Over many years, Hubble's pioneering observations repeatedly accomplished what ground-based telescopes could not — imaging features on Pluto's surface, finding new Plutonian moons, and tracking down a destination to visit after Pluto — an even tinier, icy object in a vast region of small worlds beyond the orbit of Neptune called the Kuiper Belt.


Image above: NASA's Hubble Space Telescope has explored the universe since the early 1990s, gathering visible, near-ultraviolet, and near-infrared imagery and spectra. From its location in space, the telescope avoids the distortion produced by Earth's atmosphere, enabling it to take images in higher resolutions at greater distances than possible with ground-based telescopes. Image Credit: NASA.

Thus began a decades-long relationship between Hubble and NASA's New Horizons mission: A legendary space-based telescope and a pioneering space probe hurtling through space at about 32,000 miles (51,500 kilometers) per hour.

In 1990, Hubble produced the first image that illuminated Pluto and its large moon Charon. After Hubble's optical repair in 1993, scientists captured even sharper images. New Horizons Principal Investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado, led the imaging projects while co-investigator Marc Buie, now at SwRI Boulder but then at Lowell Observatory where Pluto was discovered, led the data analysis.

Where is New Horizons? Image Credit: JHUAPL

"We got eight pixels of Pluto in 1994. Each pixel represented more than 150 square miles of Pluto's surface. Fast forward to 2002 and we got even fewer pixels per image. We had to wring every bit of information from each pixel possible," Buie said. "It was a time- and computer-intensive process, but we were able to create the first maps of Pluto's surface, and they were truly spectacular for their time."

Those crude but valuable maps provided the best evidence that Pluto was not simply a homogenous ball of ices, but has a complex, variegated surface — a promising aspect for close-up inspection by a visiting spacecraft. Hubble's cameras revealed nearly a dozen distinctive bright features, none of which had ever been seen before, including a "ragged" northern polar cap bisected by a dark strip, a puzzling high-contrast bright spot seen rotating with the planet, a cluster of dark spots, and a bright linear marking. That bright spot feature, unusually rich in carbon monoxide frost, became the prime target for New Horizons to examine up close after NASA funded the mission in 2002.


Image above: This is the first detection of Ultima Thule using the highest resolution mode of the Long Range Reconnaissance Imager (LORRI) aboard the New Horizons spacecraft. Three separate images, each with an exposure time of 0.5 seconds, were combined to produce the image. All three images were taken on Dec. 24, when Ultima was 4 billion miles (6.5 billion kilometers) from the Sun and 6.3 million miles (10 million kilometers) from the New Horizons spacecraft.(Click for full caption). Image Credits: NASA/JHUAPL/SwRI.

Although Charon was discovered in 1978 using ground-based telescopes, Hubble detected all four of Pluto's other moons: Nix and Hydra in 2005, Kerberos in 2011, and Styx in 2012. These moons were spotted in the Hubble images by New Horizons team members, most notably Project Scientist Hal Weaver of the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, and co-investigator Mark Showalter of the SETI Institute in Mountain View, California. By the time the latter two moons were discovered, New Horizons was in the final years of its almost decade-long, 3-billion-mile sprint from Earth to Pluto.


Image above: Illustration of NASA’s New Horizons spacecraft encountering 2014 MU69 – nicknamed “Ultima Thule” – a Kuiper Belt object that orbits one billion miles beyond Pluto. Set for New Year’s 2019, New Horizons’ exploration of Ultima will be the farthest space probe flyby in history. Image Credits: NASA/JHUAPL/SwRI.

The discovery of these four small satellites was critical to overall Pluto flyby planning by identifying potential hazards, verifying the optimal spacecraft trajectory, and establishing the need for time to include observations of them as part of the flyby observing sequence. Without Hubble, New Horizons would have discovered these moons only a few months before the encounter — too late to effectively plan for their detailed study. To examine the possibility for an extended mission into the Kuiper Belt, the New Horizons team used Hubble in 2014 to conduct a needle-in-a-haystack search for a suitable Kuiper Belt Object that New Horizons could visit after passing Pluto. Hubble's sensitive telescope allowed it to look for fainter KBOs than ground-based telescopes can see. Hubble took deep exposures on 20 areas of the sky and found three suitable KBO targets about one billion miles beyond Pluto. Following NASA approval for a mission extension in 2016, Stern selected 2014 MU69, since nicknamed Ultima Thule, as the target for its January 2019 flyby. In the years since, Hubble has measured the target's red color and refined its orbit with dozens of additional observations.


Image above: NASA's Hubble Space Telescope discovered the next target for the New Horizons spacecraft — 2014 MU69, nicknamed Ultima Thule — in June 2014. Seen in these five overlaid images, the object resides more than one billion miles beyond Pluto in the frigid outer reaches of the Kuiper Belt. New Horizons will reach Ultima Thule on New Year's Day 2019. Image Credits: NASA/STScI/JHUAPL/SwRI.

"Without Hubble there would be no flyby of Ultima Thule," said Stern. "And without Hubble, New Horizons would not have been as productive studying Pluto's small moons. In fact, without Hubble's early images revealing how interesting Pluto's surface markings are, there might have never been a mission to explore this fascinating dwarf planet."

New Horizons Beyond Pluto

The New Horizons spacecraft is now on course to fly by Ultima Thule — the farthest object ever explored by humankind — on New Year's Day, Jan. 1, at 12:33 a.m. EST. Follow New Horizons to Ultima Thule at http://pluto.jhuapl.edu/Mission/Where-is-New-Horizons.php.

For more information on the New Horizons mission, including fact sheets, schedules, video and images, visit: https://www.nasa.gov/newhorizons

Images (mentioned), Video, Text, Credits: NASA/JHUAPL.

Happy New Year, Orbiter.ch