samedi 2 mars 2019

NASA Secures First International Partnership for Moon to Mars Lunar Gateway












NASA logo.

March 2, 2019

The following is a statement from NASA Administrator Jim Bridenstine on the announcement Thursday by Canadian Prime Minister Justin Trudeau about Canada’s support for the Gateway lunar outpost and deep space exploration:

“NASA is thrilled that Canada is the first international partner for the Gateway lunar outpost. Space exploration is in Canada’s DNA. In 1962, Canada became the third nation to launch a satellite into orbit with Alouette 1.

“Today, Canada leads the world in space-based robotic capabilities, enabling critical repairs to the Hubble Space Telescope and construction of the International Space Station. Our new collaboration on Gateway will enable our broader international partnership to get to the Moon and eventually to Mars.”


Image above: In this illustration, NASA's Orion spacecraft approaches the Gateway in lunar orbit. Image Credit: NASA.

Related article:

Canada Commits to Joining NASA at the Moon
https://orbiterchspacenews.blogspot.com/2019/02/canada-commits-to-joining-nasa-at-moon.html

Related links:

ASC-CSA release: http://www.asc-csa.gc.ca/eng/astronomy/moon-exploration/default.asp?utm_source=website&utm_medium=news&utm_campaign=moon-exploration&utm_content=lunar-gateway&utm_term=home-page

For more information on the Gateway, visit: https://www.nasa.gov/topics/moon-to-mars/lunar-outpost

Learn more about NASA’s Moon to Mars exploration plan, go to: https://www.nasa.gov/topics/moon-to-mars

Image (mentioned), Text, Credits: NASA/Karen Northon/Bettina Inclán.

Greetings, Orbiter.ch

The future "Concorde" will have to be silent







Boom logo.

March 2, 2019

Boom - Supersonic Passenger Airplane

Several projects are underway to recreate a supersonic aircraft, 50 years after the Concorde's first flight. But he will have to be quieter.

Fifty years after the first test flight of the Concorde, March 2, 1969, the supersonic is still dreaming: several projects are underway in the United States but in the hour of increasing environmental requirements, the future aircraft at very high speed will have to be quieter.

A flight 50 years ago

The supersonic aircraft Concorde took flight 50 years ago in Toulouse, south-west France, under the command of test pilot André Turcat in front of a crowd of journalists and curious, admiring the "big white bird" ".

Born in November 1962 from a bilateral agreement between London and Paris, the supersonic project experienced, from the start, strong turbulence. The two partner companies, British Aircraft Corporation (now BAE Sytems) and Sud-Aviation (predecessor of Airbus) diverged on the characteristics of the aircraft: long-haul capable of crossing the Atlantic for the first, medium-haul for the second, like the famous Caravelle.

The name of the project was disputed, between "Concord" and "Concorde", although the word refers to the identical agreement in both languages. In 1967, Britain's Tony Benn, Secretary of State for Technology, decided that the final "e" would be added to "Concord" to mean "Excellence", "England", "Europe" and "Entente cordiale".

It will take nearly seven years and 5500 hours of test flight for Concorde to be allowed to start its commercial life, under the colors of Air France and British Airways

In the 1970s, the Concorde took off with a noise level of 119.4 decibels - now unacceptable in view of international standards - and the supersonic "bang" caused by the crossing of the sound barrier by the aircraft flying at a speed of cruising speed Mach 2.04 (2.500 km / h), twice the speed of sound, forbade him to fly over inhabited areas.

The first Concorde

"The economic interests of supersonic business jet projects can only be confirmed if the regulation allows the overflight of land and the lock is the supersonic bang," says Gerald Carrier, head of the applied aerodynamics department of the Onera, the French center for aerospace research.

"It is on this lock that have focused research for 10 years on the side of NASA. It must be recognized that they played a role in the advances that now allow us to reasonably believe that a supersonic low-boom aircraft is at hand, "he adds.

In July, NASA and Onera signed a research partnership on the supersonic bang. The "beautiful white bird", which has been a commercial fiasco, has been sheltered since 2003.

"Since the 1960s, the noise of subsonic aircraft has been divided by four," said Bruno Hamon, head of the Office of Environmental Performance of Aircraft at the General Directorate of Civil Aviation (DGCA).

Today, he explains, a standoff between Europeans and Americans in the commission created by ICAO, the United Nations agency specializing in air transport, to define acoustic standards for a supersonic future .

Possible "regression"

"Europeans want supersonic standards to be subsonic and Americans (...) want the standard to allow their aircraft projects to go on the market," says Hamon.

The US position in favor of "a less ambitious standard than that of subsonics" would be perceived "as a regression", with "reactions to be feared by the public", he continues, denouncing the idea of ​​putting on the market an airplane that would make more noise "while the subsonic aviation conceded huge efforts" in this direction.

On the subject of the "bang", whose "intensity is that of the two explosions of a final fireworks", according to Mr. Hamon, Europe collaborates in the project Rumble (Regulation and Norm for Low Sonic Boom Levels ) to assist ICAO in defining an acceptable standard for the supersonic bang.

NASA X59 QueSST plane

Several supersonic aircraft projects, all the size of a business jet, are being studied by start-ups in the United States, including Aerion, the most advanced, with a capacity of 8 to 12 passengers, the Spike S-512, of the same capacity, and the Boom project, the most ambitious, to carry 45 to 50 passengers.

The US manufacturer Boeing also unveiled in June its concept of "hypersonic" airliner, he hopes to fly Mach 5 - five times the speed of sound - for a possible commissioning in 20 or 30 years.

And two months ago, NASA signed an agreement with Lockheed Martin on the development of a supersonic "Avion-X", which will have the mission to cross the wall of sound without producing the "bang" and thus flying over the territories inhabited. "The risk is not zero to see America develop a supersonic," said Thursday Eric Trappier, CEO of Dassault Aviation.

"Technically, we have the skills to make a supersonic airplane (...) The problem is the standards," he continued, adding furthermore not to be "sure that the business plan is very credible" .

Related articles:

NASA’s Quiet Supersonic Technology Project Passe Major Milestone
https://orbiterchspacenews.blogspot.com/2018/11/nasas-quiet-supersonic-technology.html

NASA’s Experimental Supersonic Aircraft Now Known as X-59 QueSST
https://orbiterchspacenews.blogspot.com/2018/06/nasas-experimental-supersonic-aircraft.html

New Supersonic Technology Designed to Reduce Sonic Booms
https://orbiterchspacenews.blogspot.com/2017/08/new-supersonic-technology-designed-to.html

Images, Text, Credits: AFP/Boom/AP/NASA/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

NASA, SpaceX Launch First Flight Test of Space System Designed for Crew













SpaceX - COTS C-1 Mission patch.

March 2, 2019


Image above: Crowd gathers to watch as NASA and SpaceX make history by launching the first commercially-built and operated American crew spacecraft and rocket to the International Space Station. The SpaceX Crew Dragon spacecraft lifted off at 2:49 a.m. EST Saturday on the company’s Falcon 9 rocket at NASA’s Kennedy Space Center in Florida. Image Credit: NASA.

For the first time in history, a commercially-built and operated American crew spacecraft and rocket, which launched from American soil, is on its way to the International Space Station. The SpaceX Crew Dragon spacecraft lifted off at 2:49 a.m. EST Saturday on the company’s Falcon 9 rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida.

SpaceX Demo-1: Falcon 9 launches Crew Dragon. Image Credit: NASA

“Today’s successful launch marks a new chapter in American excellence, getting us closer to once again flying American astronauts on American rockets from American soil,” said NASA Administrator Jim Bridenstine. “I proudly congratulate the SpaceX and NASA teams for this major milestone in our nation’s space history. This first launch of a space system designed for humans, and built and operated by a commercial company through a public-private partnership, is a revolutionary step on our path to get humans to the Moon, Mars and beyond.”

Known as Demo-1, SpaceX’s inaugural flight with NASA’s Commercial Crew Program is an important uncrewed mission designed to test the end-to-end capabilities of the new system. It brings the nation one-step closer to the return of human launches to the space station from the United States for the first time since 2011 – the last space shuttle mission. Teams still have work to do after this flight to prepare the spacecraft to fly astronauts. The best way to advance the system design was to fly this spacecraft and uncover any other areas or integrated flight changes that might be required.

SpaceX Demo-1: Falcon 9 launches Crew Dragon & Falcon 9 first stage landing

The program demonstrates NASA’s commitment to investing in commercial companies through public-private partnerships and builds on the success of American companies, including SpaceX, already delivering cargo to the space station. Demo-1 is a critical step for NASA and SpaceX to demonstrate the ability to safely fly missions with NASA astronauts to the orbital laboratory.

“First a note of appreciation to the SpaceX team. It has been 17 years to get to this point, 2002 to now, and an incredible amount of hard work and sacrifice from a lot of people that got us to this point...I’d also like to express great appreciation for NASA,” said Elon Musk, CEO and lead designer at SpaceX. “SpaceX would not be here without NASA, without the incredible work that was done before SpaceX even started and without the support after SpaceX did start.”

The public-private partnership combines commercial companies’ unique, innovative approaches to human spaceflight and NASA’s decades-long experience in design, development and operations of a crew space system.

“We are watching history being made with the launch of the SpaceX Demo-1 mission,” said Steve Stich, launch manager and deputy manager of NASA’s Commercial Crew Program. “SpaceX and NASA teams have been working together for years, and now we are side-by-side in control rooms across the country for launch, in-orbit operations and, eventually, splashdown of the Crew Dragon right here off Florida’s coast.”

SpaceX controlled the launch of the Falcon 9 rocket from Kennedy’s Launch Control Center Firing Room 4, the former space shuttle control room, which SpaceX has leased as its primary launch control center. As Crew Dragon ascended into space, SpaceX commanded the Crew Dragon spacecraft from its mission control center in Hawthorne, California. NASA teams will monitor space station operations throughout the flight from Mission Control Center at the agency’s Johnson Space Center in Houston.

The SpaceX Crew Dragon spacecraft is on its way to the space station for a 6:05 a.m. Sunday, March 3 docking to the low-Earth orbit destination. Live coverage of the rendezvous and docking will air on NASA Television and the agency’s website beginning at 3:30 a.m. Coverage will resume at 8:30 a.m. with the hatch opening, followed at 10:45 a.m. with a crew welcoming ceremony.

Teams in the space station mission center at Johnson will monitor station crew members’ opening of the spacecraft hatch, entering Crew Dragon and unpacking the capsule.

Mission Objectives

All the launch pad and vehicle hardware, and the launch day operations, were conducted in preparation for the next flight with crew aboard, including the control teams and ground crews. The mission and testing continues once the Falcon 9 lifts off the pad.

During the spacecraft’s approach, in-orbit demonstrations will include rendezvous activities from a distance of up to 2.5 miles (4 kilometers), known as far field, and activities within one mile (1.6 kilometers), known as near field. As the spacecraft approaches the space station, it will demonstrate its automated control and maneuvering capabilities by reversing course and backing away from the station before the final docking sequence.

The docking phase, as well as the return and recovery of Crew Dragon, include many first-time events that cannot be totally modeled on the ground and, thus, are critical to understanding the design and systems ability to support crew flights. Previous cargo Dragon vehicles have been attached to the space station after capture by the station’s robotic arm. The Crew Dragon will approach to dock using new sensor systems, new propulsion systems and the new international docking mechanism to attach to the station’s Harmony module forward port, fitted with a new international docking adapter. Astronauts installed the adapter during a spacewalk in August 2016, following its delivery to the station in the trunk of a SpaceX Dragon spacecraft on its ninth commercial resupply services mission.  

For Demo-1, Crew Dragon is carrying more than 400 pounds of crew supplies and equipment to the space station and will return some critical research samples to Earth. A lifelike test device named Ripley also will travel on the Crew Dragon, outfitted with sensors to provide data on potential effects on humans traveling in Crew Dragon.

Artist's view of  SpaceX Crew Dragon. Image Credit: SpaceX

For operational missions, Crew Dragon will be able to launch as many as four crew members and carry more than 220 pounds of cargo, enabling the expansion of the crew members, increasing the time dedicated to research in the unique microgravity environment, and returning more science back to Earth.

The Crew Dragon is designed to stay docked to station for up to 210 days, although the Crew Dragon used for this flight test will not have that capability. This spacecraft will remain docked to the space station only five days, departing Friday, March 8. After undocking from the station, Crew Dragon will begin its descent to Earth. Live coverage of the undocking will air on NASA Television and the agency’s website beginning at 2 a.m., with deorbit and landing coverage resuming at 7:30 a.m. 

Additional spacecraft mission objectives include a safe departure from the station, followed by a deorbit burn and parachute deployment to slow the spacecraft before splashdown in the Atlantic Ocean, off the Florida Space Coast. SpaceX’s recovery ship, Go Searcher, will retrieve Crew Dragon and transport it back to port. Teams will be closely monitoring the parachute system and entry control system operation, which have been changed from cargo Dragons to provide higher reliability for crew flights.

NASA and SpaceX will use data from Demo-1, along with planned upgrades and additional qualification testing, to further prepare for Demo-2, the crewed flight test that will carry NASA astronauts Bob Behnken and Doug Hurley to the International Space Station. NASA will validate the performance of SpaceX’s systems before putting crew on board for the Demo-2 flight, currently targeted for July.

NASA’s Commercial Crew Program is working with Boeing and SpaceX to design, build, test and operate safe, reliable and cost-effective human transportation systems to low-Earth orbit. Both companies are focused on test missions, including abort system demonstrations and crew flight tests, ahead of regularly flying crew missions to the space station. Both companies’ crewed flights will be the first times in history NASA has sent astronauts to space on systems owned, built, tested and operated by private companies.

Learn more about NASA’s Commercial Crew program at: https://www.nasa.gov/commercialcrew

Commercial Space: http://www.nasa.gov/exploration/commercial/index.html

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

NASA Television: https://www.nasa.gov/live/

SpaceX: https://www.spacex.com/

Images (mentioned), Video, Text, Credits: NASA/Katherine Brown/Josh Finch/Stephanie Schierholz/KSC/Stephanie Martin/Marie Lewis/JSC/Kyle Herring/Dan Huot/NASA TV/SciNews.

Best regards, Orbiter.ch

vendredi 1 mars 2019

LHC: pushing computing to the limits













CERN - European Organization for Nuclear Research logo.

1 March, 2019

The Large Hadron Collider produced unprecedented volumes of data during its two multi-year runs, and, with its current upgrades, more computing challenges are in store 


Image above: Racks of computers in CERN’s computing centre are just a fraction of the hardware needed to store and process the data from the LHC (Image: Anthony Grossir/CERN).

At the end of 2018, the Large Hadron Collider (LHC) completed its second multi-year run (“Run 2”) that saw the machine reach a proton–proton collision energy of 13 TeV, the highest ever reached by a particle accelerator. During this run, from 2015 to 2018, LHC experiments produced unprecedented volumes of data with the machine’s performance exceeding all expectations.

This meant exceptional use of computing, with many records broken in terms of data acquisition, data rates and data volumes. The CERN Advanced Storage system (CASTOR), which relies on a tape-based backend for permanent data archiving, reached 330 PB of data (equivalent to 330 million gigabytes) stored on tape, an equivalent of over 2000 years of 24/7 HD video recording. In November 2018 alone, a record-breaking 15.8 PB of data were recorded on tape, a remarkable achievement given that it corresponds to more than what was recorded during the first year of the LHC’s Run 1.

The distributed storage system for the LHC experiments exceeded 200 PB of raw storage with about 600 million files. This system (EOS) is disk-based and open-source, and was developed at CERN for the extreme LHC computing requirements. As well as this, 830 PB of data and 1.1 billion files were transferred all over the world by File Transfer Service. To face these computing challenges and to better support the CERN experiments during Run 2, the entire computing infrastructure, and notably the storage systems, went through major upgrades and consolidation over the past few years.


Graphic above: Data (in terabytes) recorded on tape at CERN month-by-month. This plot shows the amount of data recorded on tape generated by the LHC experiments, other experiments, various back-ups and users. In 2018, over 115 PB of data in total (including about 88 PB of LHC data) were recorded on tape, with a record peak of 15.8 PB in November (Image: Esma Mobs/CERN).

New IT research-and-development activities have already begun in preparation for the LHC’s Run 3 (foreseen for 2021 to 2023). “Our new software, named CERN Tape Archive (CTA), is the new tape storage system for the custodial copy of the physics data and a replacement for its predecessor, CASTOR. The main goal of CTA is to make more efficient use of the tape drives, to handle the higher data rate anticipated during Run 3 and Run 4 of the LHC,” explains German Cancio, who leads the Tape, Archive & Backups storage section in CERN’s IT department. CTA will be deployed during the ongoing second long shutdown of the LHC (LS2), replacing CASTOR. Compared to the last year of Run 2, data archival is expected to be two-times higher during Run 3 and five-times higher or more during Run 4 (foreseen for 2026 to 2029).

The LHC’s computing will continue to evolve. Most of the data collected in CERN’s data centre is highly valuable and needs to be preserved and stored for future generations of physicists. CERN’s IT department will therefore be taking advantage of LS2, the current maintenance and upgrade of the accelerator complex, to perform the required consolidation of the computing infrastructure. They will be upgrading the storage infrastructure and software to face the likely scalability and performance challenges when the LHC restarts in 2021 for Run 3.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Related links:

Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider

CERN Advanced Storage system (CASTOR): http://castor.web.cern.ch/

This system (EOS): https://eos.web.cern.ch/

File Transfer Service: https://fts.web.cern.ch/

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Graphic (mentioned), Text, Credits: CERN/Esra Ozcesmeci.

Best regards, Orbiter.ch

NASA, SpaceX Prepare for March 2 Launch of Demo-1













SpaceX - COTS C-1 Mission patch.

March 1, 2019

Liftoff of the SpaceX Falcon 9 for Demo-1, the first flight test of the company’s Crew Dragon spacecraft, is targeted for Saturday, March 2, at 2:49 a.m. EST from historic Launch Complex 39A at NASA’s Kennedy Space Center in Florida. On this uncrewed mission, the first under the agency’s Commercial Crew Program, the Crew Dragon will fly to the International Space Station in an end-to-end demonstration of the company’s ability to launch astronauts to the orbiting laboratory and return them home. To learn more, read the prelaunch feature story.


Image above: A SpaceX Falcon 9 rocket with the company’s Crew Dragon spacecraft onboard is seen after being raised into a vertical position on the launch pad at Launch Complex 39A as preparations continue for the Demo-1 mission, Feb. 28, 2019, at NASA’s Kennedy Space Center in Florida. Photo credits: NASA/Joel Kowsky.

Join us at 2 a.m. for countdown coverage here on the blog and on NASA TV: https://www.nasa.gov/live

Mission Timeline (all times approximate) COUNTDOWN (EST)
Min/Sec—Events
-45:00—SpaceX Launch Director verifies “go” for propellant load
-37:00—Dragon launch escape system is armed
-35:00—RP-1 (rocket grade kerosene) loading begins
-35:00—First stage LOX (liquid oxygen) loading begins
-16:00—Second stage LOX loading begins
-07:00—Falcon 9 begins engine chill prior to launch
-05:00—Dragon transitions to internal power
-01:00—Command flight computer to begin final prelaunch checks
-01:00—Propellant tank pressurization to flight pressure begins
-00:45—SpaceX Launch Director verifies go for launch
-00:03—Engine controller commands engine ignition sequence to start
-00:00—Liftoff of the SpaceX Falcon 9 rocket and Crew Dragon spacecraft

LAUNCH, LANDING AND DRAGON DEPLOYMENT (EST)
Min/Sec—Events
00:58—Max Q (moment of peak mechanical stress on the rocket)
02:35—First stage main engine cutoff (MECO)
02:38—First and second stages separate
02:42—Second stage engine starts
07:48—First stage entry burn
08:59—Second stage engine cutoff (SECO-1)
09:24—First stage landing burn
09:52—First stage landing
11:00—Dragon separates from second stage

Related links:

NASA TV: https://www.nasa.gov/live

Commercial Crew Program: https://www.nasa.gov/commercialcrew

International Space Station (ISS): https://www.nasa.gov/station

Image (mentioned), Text, Credits: NASA/Anna Heiney.

Best regards, Orbiter.ch

NASA Scientists Show How Ingredients for Water Could Be Made on Surface of Moon, a 'Chemical Factory'













NASA Goddard Space Flight Center logo.

March 1, 2019

When a stream of charged particles known as the solar wind careens onto the Moon’s surface at 450 kilometers per second (or nearly 1 million miles per hour), they enrich the Moon’s surface in ingredients that could make water, NASA scientists have found.

Using a computer program, scientists simulated the chemistry that unfolds when the solar wind pelts the Moon’s surface. As the Sun streams protons to the Moon, they found, those particles interact with electrons in the lunar surface, making hydrogen (H) atoms. These atoms then migrate through the surface and latch onto the abundant oxygen (O) atoms bound in the silica (SiO2) and other oxygen-bearing molecules that make up the lunar soil, or regolith. Together, hydrogen and oxygen make the molecule hydroxyl (OH), a component of water, or H2O.


Image above: Waxing gibbous Moon at 11 days old. Credit: Ernie Wright/NASA.

“We think of water as this special, magical compound,” said William M. Farrell, a plasma physicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who helped develop the simulation. “But here’s what’s amazing: every rock has the potential to make water, especially after being irradiated by the solar wind.”

Understanding how much water — or its chemical components — is available on the Moon is critical to NASA’s goal of sending humans to establish a permanent presence there, said Orenthal James Tucker, a physicist at Goddard who spearheaded the simulation research.

“We’re trying to learn about the dynamics of transport of valuable resources like hydrogen around the lunar surface and throughout its exosphere, or very thin atmosphere, so we can know where to go to harvest those resources,” said Tucker, who recently described the simulation results in the journal JGR Planets.


Animation above: Credits: NASA/JoAnna Wendel.

Several spacecraft used infrared instruments that measure light emitted from the Moon to identify the chemistry of its surface. These include NASA’s Deep Impact spacecraft, which had numerous close encounters with the Earth-Moon system en route to comet 103P/Hartley 2; NASA’s Cassini spacecraft, which passed the Moon on its way to Saturn; and India’s Chandrayaan-1, which orbited the Moon a decade ago. All found evidence of water or its components (hydrogen or hydroxyl).

But how these atoms and compounds form on the Moon is still an open question. It’s possible that meteor impacts initiate the necessary chemical reactions, but many scientists believe that the solar wind is the primary driver.


Image above: The Sun releases a constant stream of particles and magnetic fields called the solar wind. This solar wind slams worlds across the solar system with particles and radiation — which can stream all the way to planetary surfaces unless thwarted by an atmosphere, magnetic field, or both. Here’s how these solar particles interact with a few select planets and other celestial bodies. Image Credits: NASA’s Goddard Space Flight Center/Mary Pat Hrybyk-Keith.

Tucker’s simulation, which traces the lifecycle of hydrogen atoms on the Moon, supports the solar wind idea.

“From previous research, we know how much hydrogen is coming in from the solar wind, we also know how much is in the Moon’s very thin atmosphere, and we have measurements of hydroxyl in the surface,” Tucker said. “What we’ve done now is figure out how these three inventories of hydrogen are physically intertwined.”

Showing how hydrogen atoms behave on the Moon helped resolve why spacecraft have found fluctuations in the amount of hydrogen in different regions of the Moon. Less hydrogen accumulates in warmer regions, like the Moon’s equator, because hydrogen atoms deposited there get energized by the Sun and quickly outgas from the surface into the exosphere, the team concluded. Conversely, more hydrogen appears to accumulate in the colder surface near the poles because there’s less Sun radiation and the outgassing is slowed.

Overall, Tucker’s simulation shows that as solar wind continually blasts the Moon’s surface, it breaks the bonds among atoms of silicon, iron and oxygen that make up the majority of the Moon’s soil. This leaves oxygen atoms with unsatisfied bonds. As hydrogen atoms flow through the Moon’s surface, they get temporarily trapped with the unhinged oxygen (longer in cold regions than in warm). They float from O to O before finally diffusing into the Moon’s atmosphere, and, ultimately, into space. “The whole process is like a chemical factory,” Farrell said.

A key ramification of the result, Farrell said, is that every exposed body of silica in space — from the Moon down to a small dust grain — has the potential to create hydroxyl and thus become a chemical factory for water.

Goddard physicist Rosemary Margaret Killen and Dana M. Hurley, planetary scientist at Johns Hopkins University in Baltimore, Maryland, contributed to the simulation research, which was funded by NASA’s Solar System Exploration Research Virtual Institute.

Related links:

Moon to Mars: https://www.nasa.gov/topics/moon-to-mars/

Earth's Moon: http://www.nasa.gov/moon

Humans in Space: https://www.nasa.gov/topics/humans-in-space

Animation & Images (mentioned), Text, Credits: NASA/Svetlana Shekhtman/Goddard Space Flight Center, by Lonnie Shekhtman.

Greetings, Orbiter.ch

jeudi 28 février 2019

Crew Dragon Ready for its Debut Flight













SpaceX - COTS C-1 Mission patch.

February 28, 2019

SpaceX’s Crew Dragon spacecraft—designed to fly astronauts to the International Space Station from U.S. soil—is ready for its debut flight on the company’s Falcon 9 rocket. It is a first-of-its-kind test mission of a commercially-built and operated American spacecraft and rocket designed for humans.

The Demo-1 uncrewed flight test, targeted to launch March 2, will demonstrate the company’s ability to safely launch crew to the space station and return them home.


Image above: A SpaceX Falcon 9 rocket with the company’s Crew Dragon spacecraft onboard is seen as it is rolled to the launch pad at Launch Complex 39A as preparations continue for the Demo-1 mission, Feb. 28, 2019 at NASA’s Kennedy Space Center in Florida. Photo credits: NASA/Joel Kowsky.

“It’s time to fly the SpaceX Demo-1 mission,” said Steve Stich, NASA launch manager and deputy manager of NASA’s Commercial Crew Program. “This mission is an important step in returning human spaceflight to American soil. SpaceX and NASA teams are working side-by-side on this mission from start to finish as we have throughout this process. This flight test will inform the system design, operations and drive any changes that need to be made ahead of crew flights. We are ready to learn by flying.”

NASA and SpaceX are working together as public-private partnerships to build on the success of American companies already delivering cargo to the space station. Demo-1 is a critical step for NASA and SpaceX to demonstrate the ability to safely fly missions with NASA astronauts to the orbital laboratory.

“Demo-1 is our end-to-end flight test to ensure the spacecraft and systems operate as designed before we put crew on board,” said Benji Reed, SpaceX director of crew mission management.

On launch day, SpaceX will command Crew Dragon and Falcon 9’s launch from Kennedy Space Center’s historic Launch Control Center Firing Room 4, which oversaw the countdown and liftoff of the final 15 space shuttle missions. Falcon 9 is targeted to lift off at 2:49 a.m. from Launch Complex 39A at NASA’s Kennedy Space Center. Pad A was the launch site for 11 Apollo Saturn V missions, including Apollo 11, the first Moon landing, and 82 space shuttle missions, including STS-1, the first shuttle launch, and STS-135, the final shuttle mission.


Image above: At NASA Kennedy Space Center’s Launch Complex 39A, the crew access arm has been extended to the SpaceX Crew Dragon spacecraft on Jan. 3, 2019. Mounted atop the company’s Falcon 9 rocket, both will undergo checkouts prior to its liftoff for Demo-1, the inaugural flight of one of the spacecraft designed to take NASA astronauts to and from the International Space Station. NASA has worked with SpaceX and Boeing in developing Commercial Crew Program spacecraft to facilitate new human spaceflight systems launching from U.S. soil with the goal of safe, reliable and cost-effective access to low-Earth orbit destinations such as the space station. Image Credit: SpaceX.

“Demo-1 is a demonstration of the Falcon 9 rocket, Crew Dragon spacecraft, ground systems and overall operations - basically just about everything that needs to be operating and operating well before we want to put our astronauts on-board,” said Mike Lee, NASA mission manager for SpaceX’s Demo-1 flight test. “Our main goals are to validate as many aspects of the spacecraft’s systems as we can without a crew on-board, monitor its approach and docking to the space station, and then monitor the undocking, deorbit, entry and splashdown.”

As Crew Dragon ascends into space, SpaceX will command Crew Dragon from its mission control center in Hawthorne, California. NASA teams will monitor operations throughout the flight from Mission Control, Houston at the agency’s Johnson Space Center.

SpaceX will test the spacecraft’s autonomous systems’ ability to maneuver and dock with the space station. During Crew Dragon’s approach, on-orbit demonstrations will include rendezvous activities from a distance of up to 2.5 miles (4 km), known as far field, and activities within one mile (1.6 km), known as near field. As the spacecraft approaches the space station, it will demonstrate its automated control and maneuvering capabilities by intentionally reversing course and backing away from the station before the final docking sequence. During this flight, Crew Dragon will dock to the station’s Harmony module forward, fitted with the new international docking adapter installed during an August 2016 spacewalk, port last used during the final shuttle mission in 2011.

The docking phase, as well as the return and recovery of Crew Dragon, include many new first-time events that cannot be totally modeled on the ground and thus are critically important to understand the design and systems ability to support crew flights. Previous cargo Dragon vehicles have been attached to the space station after capture by the station’s robotic arm. The Crew Dragon will fly in all the way to dock using new sensor systems, new propulsion systems and docking mechanism to attach to station.


Image above: A SpaceX Falcon 9 rocket with the company’s Crew Dragon attached, rolls out of the company’s hangar at NASA Kennedy Space Center’s Launch Complex 39A on Jan. 3, 2019. The rocket will undergo checkouts prior to the liftoff of Demo-1, the inaugural flight of one of the spacecraft designed to take NASA astronauts to and from the International Space Station. Image Credit: SpaceX.

or Demo-1, Crew Dragon will carry about 400 pounds of crew supplies and equipment to the space station and return some critical research samples to Earth. Teams in the space station Mission Control Center at Johnson will monitor station crew members’ opening of the spacecraft hatch, enter Crew Dragon and unpack the capsule. The spacecraft will remain docked to the space station for about two weeks. Ultimately, on future missions, Crew Dragon will be able to stay docked to station for up to 210 days during NASA crew rotation missions.

After undocking from station, Crew Dragon will begin its descent to Earth. Additional spacecraft mission objectives will include a safe departure from the station followed by a deorbit burn and parachute deployment to slow the spacecraft before splashdown in the Atlantic Ocean off the Florida Space Coast. SpaceX’s recovery ship, Go Searcher, will retrieve Crew Dragon and transport it back to port.

NASA and SpaceX will use data from Demo-1 to further prepare for Demo-2, the crewed flight test that will carry NASA astronauts Bob Behnken and Doug Hurley to the International Space Station. NASA will validate the performance of SpaceX’s systems before putting crew on-board for the Demo-2 flight, currently targeted for July.

Commercial crew is working with both Boeing and SpaceX to design, build, test and operate safe, reliable and cost-effective human transportation systems to low-Earth orbit. Both companies are targeting to have flight tests with NASA astronauts in 2019, which will restore the nation’s human launch capability to and from the station.

NASA continues to work with Boeing as the company plans for the uncrewed flight test of its CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket, known as the Orbital Flight Test, targeted for NET April 2019. Boeing’s Crew Flight Test is targeted for NET August 2019.

NASA to Provide Coverage of SpaceX Commercial Crew Flight Test


Image above:his illustration depicts SpaceX’s Crew Dragon spacecraft and Falcon 9 rocket lifting off from historic Launch Complex 39A at NASA’s Kennedy Space Center in Florida. Image Credit: SpaceX.

NASA and SpaceX are targeting 2:49 a.m. EST Saturday, March 2, for the launch of the company’s uncrewed Demo-1 flight, which will be the first time a commercially built and operated American rocket and spacecraft designed for humans will launch to the space station. The launch, as well as other activities leading up to the launch, will air on NASA Television and the agency’s website: http://www.nasa.gov/live

Related links:

Commercial Space: http://www.nasa.gov/exploration/commercial/index.html

Commercial Crew: https://www.nasa.gov/exploration/commercial/crew/index.html

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

Images (mentioned), Text, Credits: NASA/KSC/Linda Herridge.

Greetings, Orbiter.ch

Vision, Psychology Tests Ahead of First U.S. Commercial Crew Mission













ISS -Expedition 58 Mission patch.

February 28, 2019

The Expedition 58 crew continued filming in virtual reality onboard the International Space Station today. The orbital residents also conducted behavior tests and eye checks throughout Thursday while preparing for the first U.S. commercial crew vehicle mission.

NASA astronaut Anne McClain logged into specialized software for a test session with the Behavioral Core Measures study. The neuropsychological test measures cognition as an astronaut conducts simulated robotic activities on a laptop computer.


Image above: SpaceX’s Crew Dragon spacecraft and Falcon 9 rocket are positioned at the company’s hangar at Launch Complex 39A at NASA’s Kennedy Space Center in Florida, ahead of the Demo-1 flight test. Image Credit: SpaceX.

Afterward, she joined Canadian Space Agency (CSA) astronaut David Saint-Jacques for eye checks in the Harmony module at the end of the day. The two swapped Crew Medical Officer roles and scanned each other’s eyes using optical tomography coherence gear. Both astronauts started the day with a standard vision test in the Destiny lab module reading characters from an eye chart.

Saint-Jacques set up a virtual reality camera in the cupola, the station’s “window to the world.” The high-tech space footage will be used to create a short cinematic, immersive film for audiences on Earth. The CSA astronaut also activated a camera to capture imagery for the Meteor space-based observation study.

International Space Station (ISS). Image Credit: NASA

The astronauts are also counting down to Sunday’s arrival of the first U.S. commercial crew vehicle on the SpaceX DM-1 mission. The uncrewed SpaceX Crew Dragon will launch from Kennedy Space Center at 2:49 a.m. EST Saturday. McClain and Saint-Jacques will greet the Crew Dragon after it docks to the Harmony module’s International Docking Adapter Sunday around 6 a.m.

Related links:

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

Behavioral Core Measures: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7537

Harmony module: https://www.nasa.gov/mission_pages/station/structure/elements/harmony

Destiny lab module: https://www.nasa.gov/mission_pages/station/structure/elements/us-destiny-laboratory

Cupola: https://www.nasa.gov/mission_pages/station/structure/elements/cupola.html

virtual reality camera: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7877

Meteor: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1174

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.

Best regards, Orbiter.ch

Canada Commits to Joining NASA at the Moon














NASA logo / CSA-ASC logo.

February 28, 2019

NASA is going back to the Moon to stay. It’s part of a bold directive from the President for the U.S. to lead a worldwide endeavor to open a new era of space exploration in a measured, sustainable way. This work is going to take collaboration with international partners, industry, and other stakeholders, and I’m delighted by Canada’s commitment today to join us in our work to go forward to the Moon and Mars.

We are excited that Canada will be a vital ally in this lunar journey as they become the first international partner for the Gateway lunar outpost with their 24 year commitment to deep space exploration and collaboration.


Canada’s friendship throughout the Space Age, and our longstanding partnership aboard the International Space Station have brought our two nations many benefits. From astronauts like David St. Jacques, currently aboard the station, to the invaluable Canadarm-2 that helps us perform many tasks on the station, everything from critical repairs to the Hubble Space Telescope to the construction of the International Space Station. Canada’s technical expertise and human resources have been an incredible component of our achievements on orbit and across the spectrum of our work. It was my great pleasure to visit Canada recently and see this innovation firsthand.

Going forward to the Moon, we’re making progress on a Gateway lunar outpost where astronauts can live and work in orbit and from which we can go to the lunar surface, again and again. We’ve begun the process for industry partners to deliver the first science instruments and tech demonstrations to the Moon’s surface, and we’re going to keep up that drumbeat until we’ve built human landers to get us back to the Moon by 2028.

Today, in addition to their incredible 24-year commitment, Canada is going to build a next generation Canadarm for the Gateway lunar outpost and support our work with industry to return to the surface of the moon, among other efforts. Canada’s technologic achievement as part of Gateway lunar outpost will be a part of creating the vital backbone for commercial and other international partnerships to get to the Moon and eventually to Mars. We are thrilled to work with Canada on the next generation of its robotics to help carry out incredible missions at the Gateway lunar outpost and to collaborate in our future on the lunar surface and deep space.

I thank Prime Minister Trudeau for his vote of confidence in the Canadian Space Agency and the many innovations that its president Sylvain Laporte and the Ministry of Innovation, Science, and Economic Development are pursuing for the Canadian people and the world. Our work in space improves life for people everywhere on this planet. We look forward to our deepening partnership with Canada, and the support of the many other nations I am confident will join us and help strengthen our progress on the challenging goals we’ve set in space.

Related links:

Canada’s commitment today: https://www.nasa.gov/press-release/nasa-secures-first-international-partnership-for-moon-to-mars-lunar-gateway

Canadian Space Agency - Agence Spatiale Canadienne (CSA-ASC): http://www.asc-csa.gc.ca/eng/default.asp

Moon to Mars: https://blogs.nasa.gov/bridenstine/category/moon-to-mars/

Image, Text, Credits: NASA/Jim Bridenstine.

Best regards, Orbiter.ch

First Evidence of Planet-Wide Groundwater System on Mars













ESA - Mars Express Mission patch.

28 February 2019

Mars Express has revealed the first geological evidence of a system of ancient interconnected lakes that once lay deep beneath the Red Planet’s surface, five of which may contain minerals crucial to life.

Example of basin features

Mars appears to be an arid world, but its surface shows compelling signs that large amounts of water once existed across the planet. We see features that would have needed water to form – branching flow channels and valleys, for example – and just last year Mars Express detected a pool of liquid water beneath the planet’s south pole.

A new study now reveals the extent of underground water on ancient Mars that was previously only predicted by models.

“Early Mars was a watery world, but as the planet’s climate changed this water retreated below the surface to form pools and ‘groundwater’,” says lead author Francesco Salese of Utrecht University, the Netherlands.

Distribution of once-watery basins on Mars

“We traced this water in our study, as its scale and role is a matter of debate, and we found the first geological evidence of a planet-wide groundwater system on Mars.”

Salese and colleagues explored 24 deep, enclosed craters in the northern hemisphere of Mars, with floors lying roughly 4000 m below martian ‘sea level’ (a level that, given the planet’s lack of seas, is arbitrarily defined on Mars based on elevation and atmospheric pressure).

They found features on the floors of these craters that could only have formed in the presence of water. Many craters contain multiple features, all at depths of 4000 to 4500 m – indicating that these craters once contained pools and flows of water that changed and receded over time.

Evolution of water-filled basins over time

Features include channels etched into crater walls, valleys carved out by sapping groundwater, dark, curved deltas thought to have formed as water levels rose and fell, ridged terraces within crater walls formed by standing water, and fan-shaped deposits of sediment associated with flowing water.

The water level aligns with the proposed shorelines of a putative martian ocean thought to have existed on Mars between three and four billion years ago.

“We think that this ocean may have connected to a system of underground lakes that spread across the entire planet,” adds co-author Gian Gabriele Ori, director of the Universita` D’Annunzio’s International Research School of Planetary Sciences, Italy.

“These lakes would have existed around 3.5 billion years ago, so may have been contemporaries of a martian ocean.”

The history of water on Mars is a complex one, and is intricately linked to understanding whether or not life ever arose there – and, if so, where, when, and how it did so.

Mars Express

The team also spotted signs of minerals within five of the craters that are linked to the emergence of life on Earth: various clays, carbonates, and silicates. The finding adds weight to the idea that these basins on Mars may once have had the ingredients to host life. Moreover, they were the only basins deep enough to intersect with the water-saturated part of Mars’ crust for long periods of time, with evidence perhaps still buried in the sediments today.

Exploring sites like these may thus reveal the conditions suitable for past life, and are therefore highly relevant to astrobiological missions such as ExoMars – a joint ESA and Roscosmos endeavour. While the ExoMars Trace Gas Orbiter is already studying Mars from above, the next mission will launch next year. It comprises a rover – recently named after Rosalind Franklin – and a surface science platform, and will target and explore martian sites thought to be key in the hunt for signs of life on Mars.

“Findings like this are hugely important; they help us to identify the regions of Mars that are the most promising for finding signs of past life,” says Dmitri Titov, ESA’s Mars Express project scientist.

“It is especially exciting that a mission that has been so fruitful at the Red Planet, Mars Express, is now instrumental in helping future missions such as ExoMars explore the planet in a different way. It’s a great example of missions working together with great success.”

Notes for editors:

Salese, F., Pondrelli, M., Neeseman, A., Schmidt, G., and Ori, G. G. (2019). Geological evidence of planet-wide groundwater system on Mars. Journal of Geophysical Research:  https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2018JE005802

Mars Express was launched on 2 June 2003, and reached 15 years in space last year. This study used observations from the High Resolution Stereo Camera (HRSC) on ESA’s Mars Express, from NASA’s High Resolution Imaging Science Experiment (HiRISE), and from the Context Camera aboard NASA’s Mars Reconnaissance Orbiter. A digital terrain model was used based on data from the HRSC and NASA’s Mars Orbiter Laser Altimeter.

Related links:

Mars Express: http://www.esa.int/Our_Activities/Space_Science/Mars_Express

HRSC data viewer: http://hrscview.fu-berlin.de/

Mars Webcam: http://blogs.esa.int/vmc

Images, Text, Credits: ESA/Markus Bauer/Dmitri Titov/NASA/JPL-Caltech/MSSS/MGS/MOLA; Crater distribution: F. Salese et al (2019)/ATG medialab; Mars: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/International Research School of Planetary Sciences, Universita` D’Annunzio, Italy/Gian Gabriele Ori/Utrecht University, the Netherlands and International Research School of Planetary Sciences/Francesco Salese.

Greetings, Orbiter.ch

Rethinking everything we thought we knew about star clusters













ESA - Gaia Mission patch.

28 February 2019

ESA's Gaia satellite is on a mission: to map and characterise more than one billion of the stars in the Milky Way. Many of these stars reside in complex, eye-catching clusters scattered throughout our Galaxy and, by studying these stellar groupings, Gaia is revealing much about the formation and evolution of stars in our cosmic home and surroundings.


Image above: Gaia's view of the sky. Image Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.

The Milky Way is full of stars. Our Galaxy contains over a hundred billion of them, from dwarf to giant, populating its crowded centre and its spiralling disc.

Many of these stars are thought to have formed in the same way: from huge clouds of cool, condensing molecular gas, which collapse under the influence of gravity and fragment to form groups of hundreds to thousands of stars, known as star clusters. Some of these clusters last thousands of millions of years, while others disperse rapidly, releasing their stellar residents into the Milky Way's disc.

It is likely that also our Sun formed in a cluster some 4.5 billion years ago, and the quest for solar siblings – stars that were born in the same cluster as the Sun and then went on different paths – will provide important information on the birth of our parent star.

Despite our growing knowledge, many open questions remain. For instance, how many clusters exist, how many are currently being formed, how many are falling apart – and at what pace?

The incredible diversity of stars and their birth clusters is currently being explored by ESA's Gaia satellite.

Launched in December 2013, Gaia aims to map the nearby cosmos and execute the most extensive census of stars ever performed, tracking the positions, motions, and properties of more than one billion stars in the Milky Way and its surroundings. So far, the mission has released two packages of data: Data Release 1 (DR1) on 14 September 2016, and Data Release 2 (DR2) on 25 April 2018.

Comparison between Gaias first and second data releases

Video above: Comparison between Gaia's first (left) and second (right) data releases. Click here for details and large versions of the video. Video Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.

"The first release was planned as more of a test release than a full database, and the second is still early days for Gaia," says Carme Jordi of the University of Barcelona, Spain, a member of the Gaia Science Team. "Nonetheless, these datasets have already offered us unique insights into the stars within our Galaxy, and in particular into stellar clusters."

Gaia DR1 contained the positions and brightnesses of 1.1 billion stars, and the parallaxes (a way of measuring distance) and proper motions (movement through the sky) for a subset of two million. Gaia DR2 raises these figures to nearly 1.7 billion stars in terms of positions and brightnesses, over 1.3 billion in terms of parallax and proper motion, and adds new data about stellar colours, line-of-sight velocities, surface temperatures, variability, radii, luminosities, and more.

With Gaia DR2, the mission has provided scientists with new tools to look at star clusters in the Sun's neighbourhood and beyond.

New clusters unveiled

Alfred Castro-Ginard and colleagues used a statistical method on a subset of Gaia DR1 to discover 21 nearby clusters that had previously gone unnoticed, confirming their findings using the full DR2 data. So far, even if not unanimously, scientists had generally thought that all such clusters out to distances between 3200 and 6500 light-years from Earth had been identified – but this study suggests that there is still much to discover, even in our cosmic neck of the woods.

"It's worth noting that this study only looked at a small part of the sky," explains Jordi. "The discovery of new nearby clusters, which should be the easiest to detect, indicates that our knowledge of these clusters is really quite incomplete out to greater distances."


Image above: Parallaxes in Gaia's sky. Image Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.

This finding was soon followed and supported by a different study, led by Tristan Cantat-Gaudin, which re-analysed every previously reported cluster, known and putative alike, using data from Gaia DR2. This research confirmed earlier detections of about 1200 clusters, and determined their average distance and overall motion.

The scientists also serendipitously discovered 60 new potential clusters, but also surprisingly discarded clusters that had previously been identified. The study revealed that many such clusters are actually overlapping groups consisting of more than one cluster, while others are just asterisms – apparent patterns or groupings of stars that are in fact tricks of perspective on the two-dimensional sky.

Another study by Cantat-Gaudin and collaborators focussed on a nearby stellar group known as Vela OB2, which is somewhat looser than an ordinary cluster. Gaia's precision allowed the scientists to study stellar motions within Vela OB2 in great detail, revealing that it comprises multiple smaller clumps of stars and that the overall complex is expanding. They used the data to unravel the history of this stellar group, which is associated with a large, expanding nearby shell of gas known as the IRAS Vela Shell and thought to have originated in a supernova explosion: according to Gaia, the powerful event that triggered this shell also sparked the formation of Vela OB2's stars over 10 million years ago.

"Gaia's extraordinary data are allowing us to revisit our existing stellar census and confirm, discard, and discover clusters," says Jordi, who is a co-author on all three studies. "This is invaluable in helping us to characterise the distribution of clusters throughout the Milky Way's disc, and their height in relation to the Galactic plane."

Tracing clusters across the Galaxy

On a broader Galactic scale, the new cluster counts that scientist have started to put together with Gaia seems to indicate that clusters sitting high above the plane of the Milky Way are old, and located further from our Galaxy's centre.

"It seems there aren't old clusters at high altitudes in the inner part of the Galactic disc, so they must have dissolved – just as our models predict," explains Jordi.

Looking specifically at clusters in higher-altitude areas of our Galaxy's disc by combining positions and motions on the sky from Gaia DR2 with line-of-sight velocities from a ground-based survey, Janez Kos and colleagues discarded the existence of four out of the five analysed clusters.

In a different study, Caroline Soubiran and colleagues used line-of-sight velocities from Gaia DR2 to explore the kinematics of 861 stellar clusters, and found them to follow the velocity distribution of field stars – stars that are not associated to any cluster – in the solar neighbourhood.

Precise data from Gaia DR2 also contributed to revealing the ongoing evaporation of the nearest cluster to the Sun, the Hyades, in two independent studies led by Stefan Meingast and Siegfried Röser, respectively. This cluster was found to boast two well-defined tidal tails containing hundreds of stars, each extending from the cluster's core in a distinct 'S' shape.

The Hyades cluster

Video above: Flythrough the Gaia data, towards the Hyades cluster. Click here for details and large versions of the video. Video Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.

"This unique finding opens a new window for studying how clusters, through their gradual demise under the influence of the Milky Way's gravity, continuously feed the Galactic disc with stars," says Jordi.

Clusters as stellar test-beds

Star clusters are not only tracers of how the disc of our Galaxy has evolved over time, but also excellent laboratories for studying stellar physics. With its unprecedented data, Gaia has started to reveal previously unseen details that have an impact on our understanding of the formation and evolution of stars.

By plotting the colour of stars against their brightness, astronomers have been using the so-called Hertzsprung-Russell (HR) diagram to study the evolution of stellar populations for over a century. In this diagram, most stars lie along a top-left to bottom-right diagonal line known as the 'main sequence' – which identifies stars in their prime, burning hydrogen fuel in their cores – while stars in later stages of their lives are found away from this sequence.

The Hertzsprung-Russell diagram

Video above: The Hertzsprung-Russell diagram. Click here for details and large versions of the video. Video Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.

In clusters, which were historically thought to contain a single, simple population of stars that formed all at the same time, the position in the diagram where the main sequence 'turns off' was customarily used to estimate the age of that particular stellar population. However, in recent years, scientists had found evidence that clusters may comprise more than one population of stars, based on the observation of multiple turn-off points in their HR diagrams.

Gaia is now calling for a rethink of this phenomenon, as several studies based on its latest dataset seem to indicate how the multiple turn-off points can be explained without invoking several populations of stars, but rather by properly including the effects of the rotation of cluster stars on their predicted colours. For example, Anna Marino and colleagues conducted two studies using photometric data from Gaia DR2 to suggest that this is a common feature in Milky Way clusters, while Beomdu Lim and colleagues found a similar result by combining Gaia proper motions with ground-based spectroscopic observations of M11, also known as the 'Wild Duck' cluster. Similarly, Giacomo Cordoni and colleagues used a mix of stellar velocity, photometry, and proper motion data to confirm that rotational effects of stars can affect their estimated colours and lifespans.

Gaia. Animation Credit: ESA

This is certainly not the final word on stellar clusters, and many more studies will follow in coming years and clarify, reopen, and perhaps even deepen these intriguing topics. Like every great mission or experiment, Gaia is providing scientists with precise and plentiful data that are increasing our understanding of many astronomical problems, giving rise to new and more profound questions as our knowledge grows.

"Gaia is unique and revolutionising all fields of astrophysics, with this recent research on star clusters being a good example," says Jos de Bruijne, Gaia deputy project scientist at ESA.

"The mission has given us precise measurements of how stars move through space and their distances from us… and it has done this for over one billion stars. We've never had anything like this database before, and it's invaluable in helping us study our Galaxy.

"The recent star-cluster discoveries make this a hugely exciting area of research – especially as we have more Gaia data releases to look forward to in coming years."

More information:

ESA's Gaia satellite was launched in 2013 to create the most precise three-dimensional map of more than one billion stars in the Milky Way. The mission has released two lots of data so far: Gaia Data Release 1 on 14 September 2016, and Gaia Data Release 2 on 25 April 2018. More releases will follow in coming years.

Related links:

Gaia Data Release 1: http://sci.esa.int/gaia/58275-data-release-1/

Gaia Data Release 2: http://sci.esa.int/gaia/60243-data-release-2/

Hertzsprung-Russell (HR) diagram: http://sci.esa.int/gaia-stellar-family-portrait/

ESA Gaia: http://sci.esa.int/gaia/

Images (mentioned), Videos (mentioned), Animation (mentioned), Text, Credit: European Space Agency (ESA).

Greetings, Orbiter.ch

mercredi 27 février 2019

Liftoff of Arianespace’s Soyuz mission with six OneWeb satellites




















Arianespace - Soyuz Flight VS21 Mission poster.

February 27, 2019

Soyuz ST-B launches OneWeb F6

Arianespace VS21 mission: a Soyuz ST-B launch vehicle launched OneWeb F6, the first six OneWeb satellites, from the Soyuz Launch Complex (ELS) in Sinnamary, French Guiana, on 26 February 2019, at 21:37 UTC (18:37 local time). The Fregat-M upper stage will place the satellites into a circular low Earth orbit at 1000 km (close to their operational orbit).

Arianespace TV - VS21 Launch Sequence

Soyuz has lifted off from the Spaceport in French Guiana, carrying the first six satellites in OneWeb’s constellation – which will be deployed during a sequence lasting 1 hour and 22 minutes from liftoff to final separation.

Payload lift performance for today’s mission – which is designated Flight VS21 in Arianespace’s launcher family numbering system – is estimated at 1,945.2 kg.

OneWeb F6 satellites deployment

OneWeb F6, the first six OneWeb satellites, were successfully deployed into a circular low Earth orbit at 1000 km (close to their operational orbit) approximately one hour after being launched by a Soyuz ST-B launch vehicle from the Soyuz Launch Complex (ELS) in Sinnamary, French Guiana, on 26 February 2019, at 21:37 UTC (18:37 local time).

OneWeb Pilot satellite

OneWeb, which is developing a constellation of hundreds of satellites in low Earth orbit for low-latency broadband communications.

Arianespace: http://www.arianespace.com/

OneWeb website: http://www.oneweb.world/

OneWeb Satellites website: http://onewebsatellites.com/

Airbus Space website: https://www.airbus.com/space.html

Images, Videos, Text, Credits: Arianespace/Airbus Space/SciNews/Orbiter.ch Aerospace.

Best regards, Orbiter.ch

Crew Studies How Space Affects the Mind and Heart













ISS - Expedition 58 Mission patch.

February 27, 2019

The Expedition 58 crew explored how living in space impacts perception and psychology today. The trio also studied satellite navigation and continued reviewing this weekend’s arrival of the first SpaceX Crew Dragon spacecraft.

Astronauts Anne McClain and David Saint-Jacques partnered up this morning inside Europe’s Columbus lab module for the Vection space perception experiment. The duo wore virtual reality goggles, earplugs and a neck brace to study microgravity’s effect on the vestibular system. They took turns performing a series of tasks documenting perception of motion, orientation, height and depth. Results may improve astronaut training and the design of future space habitats.


Image above: Astronauts (from left) David Saint-Jacques and Anne McClain wear a head-mounted display for the Time Perception study which hypothesizes that crews underestimate the duration of time in space. Image Credit: NASA.

McClain then spent the rest of the day in the Japanese Kibo lab module operating a pair of tiny internal satellites for the SmoothNav study. The experiment is researching how autonomous satellites may benefit future public and private space exploration.

International Space Station (ISS). Animation Credit: NASA

Saint-Jacques went in to the afternoon reviewing rendezvous and docking operations when the uncrewed SpaceX DM-1 spacecraft arrives Sunday at 6 a.m. EST. He wrapped up his workday helping psychologists understand the adverse effects of living in space on an astronaut’s cognition and behavior.

Commander Oleg Kononenko participated in a Russian cardiopulmonary study before installing communications gear in the Zvezda service module. In the afternoon, two-time station commander collected radiation readings and ensured the upkeep of Russian life support systems.

Related links:

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

Columbus lab module: https://www.nasa.gov/mission_pages/station/structure/elements/europe-columbus-laboratory

Vection: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7484

Kibo lab module: https://www.nasa.gov/mission_pages/station/structure/elements/japan-kibo-laboratory

SmoothNav: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7532

SpaceX DM-1: https://www.nasa.gov/press-release/nasa-spacex-demo-1-briefings-events-and-broadcasts

Cognition and behavior: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7537

Cardiopulmonary study: https://www.energia.ru/en/iss/researches/human/19.html

Zvezda service module: https://www.nasa.gov/mission_pages/station/structure/elements/zvezda-service-module.html

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

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch