samedi 21 octobre 2017

Bigelow Aerospace and United Launch Alliance Announce Agreement to Place a B330 Habitat in Low Lunar Orbit








Bigelow Aerospace logo / United Launch Alliance (ULA) logo.

Oct. 21, 2017

Bigelow Aerospace and United Launch Alliance (ULA) are working together to launch a B330 expandable module on ULA’s Vulcan launch vehicle.  The launch would place a B330 outfitted module in Low Lunar Orbit by the end of 2022 to serve as a lunar depot.

B330 Habitat in Low Lunar Orbit

“We are excited to work with ULA on this lunar depot project,” said Robert Bigelow, president of Bigelow Aerospace. “Our lunar depot plan is a strong complement to other plans intended to eventually put people on Mars. It will provide NASA and America with an exciting and financially practical success opportunity that can be accomplished in the short term. This lunar depot could be deployed easily by 2022 to support the nation’s re-energized plans for returning to the Moon.

"This commercial lunar depot would provide anchorage for significant lunar business development in addition to offering NASA and other governments the Moon as a new exciting location to conduct long-term exploration and astronaut training.”

video
B330 A Fully Autonomous Stand -Alone Space Station description

The B330 would launch to Low Earth Orbit on a Vulcan 562 configuration rocket, the only commercial launch vehicle in development today with sufficient performance and a large enough payload fairing to carry the habitat. Once the B330 is in orbit, Bigelow Aerospace will outfit the habitat and demonstrate it is working properly.  Once the B330 is fully operational, ULA’s industry-unique distributed lift capability would be used to send the B330 to lunar orbit.  Distributed lift would also utilize two more Vulcan ACES launches, each carrying 35 tons of cryogenic propellant to low Earth orbit.  In LEO, all of the cryogenic propellant would be transferred to one of the Advanced Cryogenic Evolved Stage (ACES). The now full ACES would then rendezvous with the B330 and perform multiple maneuvers to deliver the B330 to its final position in Low Lunar Orbit.


Image above: Radiation Protection and Debris Shielding. Terrestrial test data and on-orbit validation suggest that a fully outfitted B330 spacecraft will have robust debris and radiation shielding.

“We are so pleased to be able to continue our relationship with Bigelow Aerospace,” said Tory Bruno, ULA’s president and CEO. “The company is doing such tremendous work in the area of habitats for visiting, living and working off our planet and we are thrilled to be the ride that enables that reality.”

Actual Bigelow module (BEAM) test on International Space Station

Bigelow Aerospace is a destination-oriented company with a focus on expandable systems for use in a variety of space applications.  These NASA heritage systems provide for greater volume, safety, opportunity and economy than the aluminum alternatives.

Launcher's, Modularity & Scalability (not to scale)

The B330 is a standalone commercial space station that can operate in low Earth orbit, cislunar space and beyond.  A single B330 is comparable to one third of the current pressurized volume of the entire International Space Station.  Bigelow Aerospace is developing two B330 commercial space station habitats that will be ready for launch any time after 2020.

Related links:

Bigelow Expandable Activity Module (BEAM): https://www.nasa.gov/content/bigelow-expandable-activity-module

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

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

For more information on Bigelow Aerospace visit http://www.bigelowaerospace.com/

For more information on United Launch Alliance (ULA), visit the ULA website at http://www.ulalaunch.com/

Images, Videos, Text, Credits: ULA/Bigelow Aerospace/NASA.

Greetings, Orbiter.ch

vendredi 20 octobre 2017

Expedition 53 Spacewalk Successfully Comes to an End














ISS - Expedition 53 Mission patch / EVA - Extra Vehicular Activities patch.

October 20, 2017


Image above: Two NASA astronauts switched their spacesuits to battery power this morning at 7:47 a.m. EDT aboard the International Space Station to begin a spacewalk. Image Credit: NASA TV.

Expedition 53 Commander Randy Bresnik and Flight Engineer Joe Acaba of NASA completed a 6 hour, 49 minute spacewalk at 2:36 p.m. EDT. The two astronauts installed a new camera system on the Canadarm2 robotic arm’s latching end effector, an HD camera on the starboard truss of the station and replaced a fuse on the Dextre robotic arm extension.

video
Space Station Crew Completes a Trio of October Spacewalks

The duo worked quickly and were able to complete several “get ahead” tasks. Acaba greased the new end effector on the robotic arm. Bresnik installed a new radiator grapple bar. Bresnik completed prep work for one of two spare pump modules on separate stowage platforms to enable easier access for potential robotic replacement tasks in the future. He nearly finished prep work on the second, but that work will be completed by future spacewalkers.


Image above: The two astronauts installed a new camera system on the Canadarm2 robotic arm’s latching end effector. Image Credit: NASA TV.

This was the fifth spacewalk of Bresnik’s career (32 hours total spacewalking) and the third for Acaba (19 hours and 46 minutes total spacewalking). Space station crew members have conducted 205 spacewalks in support of assembly and maintenance of the orbiting laboratory. Spacewalkers have now spent a total of 53 days, 6 hours and 25 minutes working outside the station.

Related links:

Expedition 53: https://www.nasa.gov/mission_pages/station/expeditions/expedition53/index.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

Images (mentioned), Video (NASA TV), Text, Credits: NASA/Melanie Whiting.

Best regards, Orbiter.ch

NASA's SDO Spots a Lunar Transit












NASA - Solar Dynamics Observatory (SDO) patch.

Oct. 20, 2017


On Oct. 19, 2017, the Moon photobombed NASA’s Solar Dynamics Observatory, or SDO, when it crossed the spacecraft’s view of the Sun, treating us to these shadowy images. The lunar transit lasted about 45 minutes, between 3:41 and 4:25 p.m. EDT, with the Moon covering about 26 percent of the Sun at the peak of its journey. The Moon’s shadow obstructs SDO’s otherwise constant view of the Sun, and the shadow’s edge is sharp and distinct, since the Moon has no atmosphere which would distort sunlight.

SDO captured these images in a wavelength of extreme ultraviolet light that shows solar material heated to more than 10 million degrees Fahrenheit. This kind of light is invisible to human eyes, but colorized here in green.

Solar Dynamics Observatory or SDO spacecraft. Image Credit: NASA

Related links:

Eclipses and Transits: https://www.nasa.gov/eclipse

SDO (Solar Dynamics Observatory): http://www.nasa.gov/mission_pages/sdo/main/index.html

Animation, Images Credits: NASA’s Goddard Space Flight Center/SDO/Joy Ng/Text: Lina Tran, NASA’s Goddard Space Flight Center, Greenbelt, Md.

Greetings, Orbiter.ch

NASA’s MAVEN Mission Finds Mars Has a Twisted Tail












NASA - MAVEN Mission logo.

Oct. 20, 2017

Mars has an invisible magnetic “tail” that is twisted by interaction with the solar wind, according to new research using data from NASA’s MAVEN spacecraft.

NASA’s Mars Atmosphere and Volatile Evolution Mission (MAVEN) spacecraft is in orbit around Mars gathering data on how the Red Planet lost much of its atmosphere and water, transforming from a world that could have supported life billions of years ago into a cold and inhospitable place today. The process that creates the twisted tail could also allow some of Mars’ already thin atmosphere to escape to space, according to the research team.

“We found that Mars’ magnetic tail, or magnetotail, is unique in the solar system,” said Gina DiBraccio of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It’s not like the magnetotail found at Venus, a planet with no magnetic field of its own, nor is it like Earth’s, which is surrounded by its own internally generated magnetic field. Instead, it is a hybrid between the two.” DiBraccio is project scientist for MAVEN and is presenting this research at a press briefing Thursday, Oct. 19 at 12:15pm MDT during the 49th annual meeting of the American Astronomical Society’s Division for Planetary Sciences in Provo, Utah.

The team found that a process called “magnetic reconnection” must have a big role in creating the Martian magnetotail because, if reconnection were occurring, it would put the twist in the tail.


Image above: Artist's conception of the complex magnetic field environment at Mars. Yellow lines represent magnetic field lines from the Sun carried by the solar wind, blue lines represent Martian surface magnetic fields, white sparks are reconnection activity, and red lines are reconnected magnetic fields that link the surface to space via the Martian magnetotail. Image Credits: Anil Rao/Univ. of Colorado/MAVEN/NASA GSFC.

“Our model predicted that magnetic reconnection will cause the Martian magnetotail to twist 45 degrees from what’s expected based on the direction of the magnetic field carried by the solar wind,” said DiBraccio. “When we compared those predictions to MAVEN data on the directions of the Martian and solar wind magnetic fields, they were in very good agreement.”

Mars lost its global magnetic field billions of years ago and now just has remnant “fossil” magnetic fields embedded in certain regions of its surface. According to the new work, Mars’ magnetotail is formed when magnetic fields carried by the solar wind join with the magnetic fields embedded in the Martian surface in a process called magnetic reconnection. The solar wind is a stream of electrically conducting gas continuously blowing from the Sun’s surface into space at about one million miles (1.6 million kilometers) per hour. It carries magnetic fields from the Sun with it. If the solar wind field happens to be oriented in the opposite direction to a field in the Martian surface, the two fields join together in magnetic reconnection.

The magnetic reconnection process also might propel some of Mars’ atmosphere into space. Mars’ upper atmosphere has electrically charged particles (ions). Ions respond to electric and magnetic forces and flow along magnetic field lines. Since the Martian magnetotail is formed by linking surface magnetic fields to solar wind fields, ions in the Martian upper atmosphere have a pathway to space if they flow down the magnetotail. Like a stretched rubber band suddenly snapping to a new shape, magnetic reconnection also releases energy, which could actively propel ions in the Martian atmosphere down the magnetotail into space.

Since Mars has a patchwork of surface magnetic fields, scientists had suspected that the Martian magnetotail would be a complex hybrid between that of a planet with no magnetic field at all and that found behind a planet with a global magnetic field. Extensive MAVEN data on the Martian magnetic field allowed the team to be the first to confirm this. MAVEN’s orbit continually changes its orientation with respect to the Sun, allowing measurements to be made covering all of the regions surrounding Mars and building up a map of the magnetotail and its interaction with the solar wind.

Mars Atmosphere and Volatile Evolution or MAVEN spacecraft. Image Credit: NASA

Magnetic fields are invisible but their direction and strength can be measured by the magnetometer instrument on MAVEN, which the team used to make the observations. They plan to examine data from other instruments on MAVEN to see if escaping particles map to the same regions where they see reconnected magnetic fields to confirm that reconnection is contributing to Martian atmospheric loss and determine how significant it is. They also will gather more magnetometer data over the next few years to see how the various surface magnetic fields affect the tail as Mars rotates. This rotation, coupled with an ever-changing solar wind magnetic field, creates an extremely dynamic Martian magnetotail. “Mars is really complicated but really interesting at the same time,” said DiBraccio.

The research was funded by the MAVEN mission. MAVEN began its primary science mission on November 2014, and is the first spacecraft dedicated to understanding Mars’ upper atmosphere. MAVEN’s principal investigator is based at the University of Colorado’s Laboratory for Atmospheric and Space Physics, Boulder. The university provided two science instruments and leads science operations, as well as education and public outreach, for the mission. NASA Goddard manages the MAVEN project and provided two science instruments for the mission, including the magnetometer. Lockheed Martin built the spacecraft and is responsible for mission operations. The University of California at Berkeley’s Space Sciences Laboratory also provided four science instruments for the mission. NASA’s Jet Propulsion Laboratory in Pasadena, California, provides navigation and Deep Space Network support, as well as the Electra telecommunications relay hardware and operations.

MAVEN (Mars Atmosphere and Volatile Evolution): https://www.nasa.gov/mission_pages/maven/main/index.html

Images (mentioned), Text, Credits: NASA/Goddard Space Flight Center, Bill Steigerwald/Nancy Jones.

Greetings, Orbiter.ch

jeudi 19 octobre 2017

A more precise measurement for antimatter than for matter












CERN - European Organization for Nuclear Research logo.

19 Oct 2017


Image above: Stefan Ulmer, spokesperson of the BASE collaboration, working on the experiment set-up. (Image: Maximilien Brice, Julien Ordan/CERN).

This week, the BASE collaboration published, in Nature, a new measurement of the magnetic moment of the antiproton, with a precision exceeding that of the proton. Thanks to a new method involving simultaneous measurements made on two separately-trapped antiprotons in two Penning traps, BASE succeeded in breaking its own record presented last January. This new result improves by a factor 350 the precision of the previous measurement and allows to compare matter and antimatter with an unprecedented accuracy.

“This result is the culmination of many years of continuous research and development, and the successful completion of one of the most difficult measurements ever performed in a Penning trap instrument,” said BASE spokesperson Stefan Ulmer.

The results are consistent with the magnetic moments of the proton and antiproton being equal, with the experimental uncertainty of the new antiproton measurement now significantly smaller than that for protons. The magnetic moment of the antiproton is found to be 2.792 847 344 1 (measured in unit of nuclear magneton), to be compared to the figure of 2.792 847 350 that the same collaboration of researchers found for the proton in 2014, at the BASE companion experiment at Mainz, in Germany.

“It is probably the first time that physicists get a more precise measurement for antimatter than for matter, which demonstrates the extraordinary progress accomplished at CERN’s Antiproton Decelerator, ” added first-author of the study Christian Smorra.

video
The BASE experiment at CERN's Antimatter Factory

Video above: Drone footage of CERN's BASE experiment (Video:Noemi Caraban/CERN).

You can read the scientific paper here: http://doi.org/10.1038/nature24048

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.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

BASE: http://home.cern/about/experiments/base

Antimatter: http://home.cern/topics/antimatter

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

Image (mentioned), Video (mentioned), Text, Credits: CERN/Corinne Pralavorio.

Best regards, Orbiter.ch

Final Spacewalk Preps Before November Cygnus Launch












ISS - Expedition 53 Mission patch.

October 19, 2017

Four Expedition 53 crewmates huddled together and made final preparations the day before the third and final spacewalk planned for October. Meanwhile, NASA’s commercial partner Orbital ATK has announced Nov. 11 as the new launch date for its Cygnus cargo carrier to the International Space Station.

Commander Randy Bresnik and Flight Engineer Joe Acaba are reviewing procedures and configuring tools before their spacewalk set for Friday at 8:05 a.m. EDT. NASA astronaut Mark Vande Hei and Paolo Nespoli from the European Space Agency will assist the spacewalkers in and out of their spacesuits and guide the duo as they work outside.


Image above: Astronaut Joe Acaba (foreground) assisted crewmates Randy Bresnik (right) and Mark Vande Hei before they began a spacewalk on Oct. 10. Image Credit: NASA.

The spacewalk was originally set for Wednesday before mission managers replanned a new set of tasks due to a camera light failure. Bresnik and Acaba will now replace the camera light assembly on the Canadarm2’s newly installed Latching End Effector and install an HD camera on the starboard truss. The duo will also replace a fuse on Dextre’s payload platform and remove thermal insulation on two electrical spare parts housed on stowage platforms.

Orbital ATK is targeting the launch of its eighth Cygnus resupply mission to the station for Nov. 11. Cygnus will make a nine-minute ascent to space after launch, then begin a two-day trek to the station where it will be installed for a month-long stay after its capture by the Canadarm2.

Related links:

Orbital ATK: https://www.nasa.gov/orbital

Expedition 53: https://www.nasa.gov/mission_pages/station/expeditions/expedition53/index.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), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

New NASA Study Improves Search for Habitable Worlds












NASA - Goddard Space Flight Center logo.

Oct. 19, 2017

New NASA research is helping to refine our understanding of candidate planets beyond our solar system that might support life.

“Using a model that more realistically simulates atmospheric conditions, we discovered a new process that controls the habitability of exoplanets and will guide us in identifying candidates for further study,” said Yuka Fujii of NASA’s Goddard Institute for Space Studies (GISS), New York, New York and the Earth-Life Science Institute at the Tokyo Institute of Technology, Japan, lead author of a paper on the research published in the Astrophysical Journal Oct. 17.


Image above: This illustration shows a star's light illuminating the atmosphere of a planet. Image Credits: NASA Goddard Space Flight Center.

Previous models simulated atmospheric conditions along one dimension, the vertical. Like some other recent habitability studies, the new research used a model that calculates conditions in all three dimensions, allowing the team to simulate the circulation of the atmosphere and the special features of that circulation, which one-dimensional models cannot do. The new work will help astronomers allocate scarce observing time to the most promising candidates for habitability.

Liquid water is necessary for life as we know it, so the surface of an alien world (e.g. an exoplanet) is considered potentially habitable if its temperature allows liquid water to be present for sufficient time (billions of years) to allow life to thrive. If the exoplanet is too far from its parent star, it will be too cold, and its oceans will freeze. If the exoplanet is too close, light from the star will be too intense, and its oceans will eventually evaporate and be lost to space. This happens when water vapor rises to a layer in the upper atmosphere called the stratosphere and gets broken into its elemental components (hydrogen and oxygen) by ultraviolet light from the star. The extremely light hydrogen atoms can then escape to space. Planets in the process of losing their oceans this way are said to have entered a “moist greenhouse” state because of their humid stratospheres.

In order for water vapor to rise to the stratosphere, previous models predicted that long-term surface temperatures had to be greater than anything experienced on Earth – over 150 degrees Fahrenheit (66 degrees Celsius). These temperatures would power intense convective storms; however, it turns out that these storms aren’t the reason water reaches the stratosphere for slowly rotating planets entering a moist greenhouse state.

“We found an important role for the type of radiation a star emits and the effect it has on the atmospheric circulation of an exoplanet in making the moist greenhouse state,” said Fujii. For exoplanets orbiting close to their parent stars, a star’s gravity will be strong enough to slow a planet’s rotation. This may cause it to become tidally locked, with one side always facing the star – giving it eternal day – and one side always facing away –giving it eternal night.

When this happens, thick clouds form on the dayside of the planet and act like a sun umbrella to shield the surface from much of the starlight. While this could keep the planet cool and prevent water vapor from rising, the team found that the amount of near-Infrared radiation (NIR) from a star could provide the heat needed to cause a planet to enter the moist greenhouse state. NIR is a type of light invisible to the human eye. Water as vapor in air and water droplets or ice crystals in clouds strongly absorbs NIR light, warming the air. As the air warms, it rises, carrying the water up into the stratosphere where it creates the moist greenhouse.

This process is especially relevant for planets around low-mass stars that are cooler and much dimmer than the Sun. To be habitable, planets must be much closer to these stars than our Earth is to the Sun. At such close range, these planets likely experience strong tides from their star, making them rotate slowly. Also, the cooler a star is, the more NIR it emits. The new model demonstrated that since these stars emit the bulk of their light at NIR wavelengths, a moist greenhouse state will result even in conditions comparable to or somewhat warmer than Earth's tropics. For exoplanets closer to their stars, the team found that the NIR-driven process increased moisture in the stratosphere gradually. So, it’s possible, contrary to old model predictions, that an exoplanet closer to its parent star could remain habitable.

This is an important observation for astronomers searching for habitable worlds, since low-mass stars are the most common in the galaxy. Their sheer numbers increase the odds that a habitable world may be found among them, and their small size increases the chance to detect planetary signals.

The new work will help astronomers screen the most promising candidates in the search for planets that could support life. “As long as we know the temperature of the star, we can estimate whether planets close to their stars have the potential to be in the moist greenhouse state,” said Anthony Del Genio of GISS, a co-author of the paper. “Current technology will be pushed to the limit to detect small amounts of water vapor in an exoplanet’s atmosphere. If there is enough water to be detected, it probably means that planet is in the moist greenhouse state.”

In this study, researchers assumed a planet with an atmosphere like Earth, but entirely covered by oceans. These assumptions allowed the team to clearly see how changing the orbital distance and type of stellar radiation affected the amount of water vapor in the stratosphere. In the future, the team plans to vary planetary characteristics such as gravity, size, atmospheric composition, and surface pressure to see how they affect water vapor circulation and habitability.


Image above: This is a plot of what the sea ice distribution could look like on a synchronously rotating ocean world. The star is off to the right, blue is where there is open ocean, and white is where there is sea ice. Image Credits: Anthony Del Genio/GISS/NASA.

The research was funded by the NASA Astrobiology Program through the Nexus for Exoplanet System Science; the NASA Postdoctoral Program, administered by Oak Ridge Affiliated Universities, Oak Ridge, Tennessee, and Universities Space Research Association, Columbia, Maryland; and a Grant-in-Aid from the Japan Society for the Promotion of Science, Tokyo, Japan (No.15K17605).

Related links:

Tokyo Institute of Technology, Japan, paper: http://iopscience.iop.org/article/10.3847/1538-4357/aa8955/meta

Astrobiology, Exoplanets: https://www.nasa.gov/content/the-search-for-life

Images (mentioned), Text, Credits: NASA Goddard Space Flight Center/Bill Steigerwald.

Greetings, Orbiter.ch