vendredi 4 septembre 2020

Space Station Science Highlights: Week of August 31, 2020













ISS - Expedition 63 Mission patch.

Sept. 4, 2020

The week of August 31, crew members aboard the International Space Station conducted scientific studies on monitoring spacecraft air, autonomous robots, and predicting spacecraft charging events.


Image above: NASA astronaut Chris Cassidy works inside the space station's Zvezda service module preparing for an event commemorating Russian space activities. Image Credit: NASA.

Now in its 20th year of continuous human presence, the space station provides a platform for long-duration research in microgravity and for learning to live and work in space. Experience gained on the orbiting lab supports Artemis, NASA’s program to go forward to the Moon and on to Mars.

Here are details on some of the microgravity investigations currently taking place:
Something is in the air

Spacecraft Atmosphere Monitor (SAM) demonstrates a small device known as a gas chromatograph mass spectrometer. It measures trace organic compounds such as nitrogen, oxygen, carbon dioxide, and water in space station air. The instrument uses little power and its regular transmission of data to the ground research team eliminates the need to return air samples to Earth for analysis. During the week, the crew powered off SAM and installed the Major Constituent Analyzer (MCA) plug, which is used to protect the sensor when the unit is off.


Image above: Taken as the International Space Station orbited above the border between Bolivia and Brazil, this image shows wildfires in the Amazon rainforest. Image Credit: NASA.

Autonomous airborne assistants

Astrobee tests three free-flying, cube-shaped robots designed to help scientists and engineers develop and test technologies including computer vision, robotic manipulation, control algorithms, and human-robot interactions. Cameras and sensors on the devices could be used to assist with routine chores and perform crew monitoring, scientific sampling, and logistics management, freeing up crew time for other science and engineering duties. Astrobee also gives ground controllers additional eyes and ears on the space station and can be operated remotely from the ground. During the week, crew members powered up the robots and performed various testing operations.

An early warning system for spacecraft charging


Image above: The Space Test Program-Houston 6 (STP-H6) payload can be seen atop of the EXPRESS Logistics Carrier-3 (ELC-3) at the far left of this image of NASA astronaut Andrew Morgan and ESA (European Space Agency) astronaut Luca Parmitano during a spacewalk in January 2020. Image Credit: NASA.

The Space Test Program-Houston 6-Spacecraft PlasmA Diagnostic suitE (STP-H6-SPADE) investigation monitors the interaction between the space station and the environment along its orbit. These interactions include hazardous charging events; these occur when a negative charge builds up on the outside of a spacecraft and can cause operational anomalies and satellite failures. SPADE senses key features of the spacecraft’s environment to provide early warning of dangerous charging and more accurately predict effects on satellite operations. Increasing reliance on satellites for many day-to-day operations creates a need to predict space conditions in much the way we forecast the daily weather. SPADE is one of a number of investigations that rely on automation and so require little or no crew involvement, increasing how many scientific investigations can be conducted on the orbiting lab.

Other investigations on which the crew performed work:

- Radi-N2, a Canadian Space Agency investigation, uses bubble detectors to better characterize the neutron environment on the space station, helping to define the risk it poses to crew members.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=874

- Crew members photograph Earth using digital handheld cameras for Crew Earth Observations (CEO). Photographs recording human-caused changes such as urban growth and reservoir construction and natural dynamic events including hurricanes and volcanic eruptions are publically available at the Gateway to Astronaut Photography of Earth.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=84

- ISS Ham Radio gives students an opportunity to talk directly with crew members via ham radio when the space station passes over their schools. This interaction engages and educates students, teachers, parents and other members of the community in science, technology, engineering, and math.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=337

Space to Ground: Following Chris: 09/04/2020

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

Gateway to Astronaut Photography of Earth: https://eol.jsc.nasa.gov/

Spacecraft Atmosphere Monitor (SAM): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1843

Astrobee: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1891

STP-H6-SPADE: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8005

Crew involvement: https://www.nasa.gov/mission_pages/station/research/news/research-aboard-iss-continues-with-nasa-astronaut-chris-cassidy

ISS National Lab: https://www.issnationallab.org/

Spot the Station: https://spotthestation.nasa.gov/

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

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

Images (mentioned), Video (NASA), Text, Credits: NASA/Michael Johnson/John Love, ISS Research Planning Integration Scientist Expedition 63.

Best regards, Orbiter.ch

Exoplanets: is there life elsewhere?







EPFL - Ecole Polytechnique Fédérale de Lausanne logo.

Sep. 4, 2020

How do you know if a distant planet is home to life? Researchers at EPFL have developed a model that can be used to interpret research results from distant "evidence of life". Explanations.


Image above: A new planet is discovered every two to three days. Image Credits: 123RF / PETER JURIK.

Twenty-five years ago, the scientific world discovered the first exoplanet, a planet that orbiting another sun in the galaxy. Since then, more than 4,300 of them have been spotted. And this is far from final! On average, a new planet is discovered every two to three days and almost 200 are said to be telluric, that is to say composed mainly of rocks like the Earth.

Biosignatures

Even if many other parameters must be added to this one to shelter life, such as the presence of water and the distance from their star, it is precisely on these "hard" objects that scientists have focused their quest. potential traces of life. In this context, the search for biosignatures by spectroscopy (study of the spectrum of a physical phenomenon) will probably become one of the most important methods and themes of astronomy in the coming years.

CHEOPS exoplanet chaser satellite

Numerous programs are thus being developed on the basis of new cutting-edge tools, such as the CHEOPS exoplanet chaser satellite, a project in which the University of Bern is participating, put into orbit in December 2019, or the James-Webb optical telescope, including the launch is scheduled for October 2021.

Start from the unknown

What will be the implications of such research? How to interpret the results? What does it mean if, in the end, only one biosignature is identified? Or what to deduce if none is detected? This is where researchers from the Swiss Federal Institute of Technology in Lausanne (EPFL), in collaboration with a team from the University of Rome Tor Vergata, intervened, by proposing an original model, based on the principle of Bayesian statistics, particularly relevant in the presence of small data samples.

"We all have a hunch that if we find evidence of the existence of life on another planet, that means it is all over the galaxy, but to what extent exactly?" notes Amedeo Balbi, professor of astronomy and astrophysics in the Department of Physics at the Roman University. "In this study, we propose a method that allows you to turn that intuition into statistics, and also to say precisely what these numbers mean in terms of quantity and abundance."

From one world to another

“One of our goals is to know how the assumptions, which attribute a certain degree of credibility to the presence of life outside the Earth, are weighed and compared in light of the new data that will be collected in the coming years ”, describes Claudio Grimaldi, researcher at the Laboratory of Complex Matter Physics at EPFL.

The study was able to determine that, given the small number of planets that will be examined in the near future, and assuming that life is born independently on other planets, the detection of a single biosignature could lead to a initially agnostic observer to conclude with a probability greater than 95% that there would be more than 100,000 inhabited planets in the galaxy, that is to say a greater number than that of pulsars, objects resulting from the explosion of a massive star in end of life. Conversely, the complete absence of biosignatures would in no way make it possible to think that we would be the only living beings and would still leave everything open to the abundance of other forms of life in the Milky Way.

Transfer of life between planets

Scientists add a notion to their analysis: that of panspermia, that is to say the possibility that the distribution of life in space is not the result of independent development, but of the transfer of microscopic organisms. or organic matter, between neighboring planets or over great distances, by comets for example. According to these options, the appearance of life would then be correlated with a factor of distance and the capacities of these different forms of life to resist the throes of transference as well as to adapt to new conditions.

Related article:

Cheops observes its first exoplanets and is ready for science
https://orbiterchspacenews.blogspot.com/2020/04/cheops-observes-its-first-exoplanets.html

Related links:

Tor Vergata University of Rome: https://en.uniroma2.it/

CHEOPS Mission Home Page: https://cheops.unibe.ch/

Ecole Polytechnique Fédérale de Lausanne (EPFL): https://www.epfl.ch/en/

Images (mentioned), Animation (ESA), Text, Credits: EPFL/GHI/ Philippe Kottelat/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Foams, meteors, muscle tone, and firing up the levitator – August Space Station science













ISS - International Space Station logo.

September 4, 2020

European space laboratory

While much of Europe was on holidays in August, it was business as usual on the International Space Station. European science continued to collect data on a range of topics looking to enhance space exploration and life on Earth.

Catching meteors

Perseid showers captured by ESA’s meteor camera

The Atmosphere–Space Interactions Monitor (ASIM), located outside the International Space Station, has been monitoring high-energy events that occur above clouds. On 10 August the science team behind one of the instruments used for observing these transient luminous events asked ground control to switch to a ten times higher sampling rate to catch meteors from the Perseid showers. This is a bonus element of ASIM outside of its primary scientific goals and the results will be interesting to see.

Fire up the levitator

Electromagnetic Levitator

The European Drawer Rack in ESA’s research module on the Space Station was activated from 3 August to prepare for a run of the Electromagnetic Levitator. This miniature furnace allows metal alloys to be melted and then solidified in mid-air so researchers can observe the process without a mould influencing results. The goal is to get a better understanding of metallurgy with a view to produce better, lighter and stronger metal alloys on Earth. Over 40 melting cycles were conducted in August, mainly on a sample of Titanium-Zirconium-Nickel alloys. Roscosmos’s Anatoly Ivanishin was the astronaut who set up the valves and inserted the samples.

Foaming

Chris holding Foam-Coarsening samples

Throughout August NASA astronaut Chris Cassidy set up and monitored samples for the Foam-Coarsening experiment. Bubbles on Earth tend to disappear quickly as gravity pulls on them and breaks the structures. In space, foam bubbles are more stable offering researchers more time to study how they form and behave.

Cell cartridges in the experiment contain a mixture of soap and water. Bubbles are generated by moving a piston at high speed. The foam is observed for up to 100 hours, during which the foam bubbles become larger but less in number. This process slows down over time so measurements stop when five bubbles are formed in each cell section. The results are analysed with laser optics and high-resolution cameras.

Maintenance and muscle tone

The MyotonPRO device measures muscle tension

Anatoly helped Chris take measurements of his muscle tone for the Myotones experiment on 20 August. This was the third measurement of four to track how astronauts’ muscles react to living in weightlessness. The measurements are done using a non-invasive, roughly smart-phone sized portable device called a MyotonPRO. Besides aiding space travel, this type of research could help improve the lives of many people on Earth. Elbow and back pain are common complaints for office workers and those carrying heavy loads, while the elderly, those on prolonged bed rest and people living sedentary lifestyles suffer from stiffness or a decline in function.

The Space Station is full of high-tech equipment and these require regular maintenance. Chris switched on and reviewed the biology laboratory Biolab for its annual check-up, and the Life Support Rack was switched on for a quarterly valve check and a software update.

Usual runnings

Cryptography ICE Cube experiment

Meanwhile, the regular experiments that run silently in the background did their thing without interruption. The Matiss boxes collected dust and bacteria as planned to assess new surfaces for future spacecraft; hibernating grape vines are settled well in cold storage to see how plants cope with weightlessness; the radiation monitors Dosis-3D continue to collect data on cosmic radiation and how much passes through the Space Station hull; and the commercial ICE Cubes facility was running throughout August for its three cubes, looking at cyber security in space and a plant synthetic biology experiment from the International Space University.

Related links:

Atmosphere–Space Interactions Monitor (ASIM): https://www.esa.int/asim

European Drawer Rack: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Columbus/European_Drawer_Rack

Electromagnetic Levitator: https://www.esa.int/ESA_Multimedia/Images/2014/05/Electromagnetic_Levitator

Biolab: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Columbus/Biolab

Life Support Rack: https://www.esa.int/acls

Matiss: https://www.esa.int/ESA_Multimedia/Images/2016/09/Clean_house

Dosis-3D: https://www.esa.int/ESA_Multimedia/Images/2019/03/Dosis-3D_radiation_monitor

ICE Cubes facility: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Research/ICE_Cubes_space_research_service_open_for_business

International Space University: https://www.isunet.edu/

Human and Robotic Exploration: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration

International Space Station (ISS): https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/International_Space_Station

Images, Animation, Text, Credits: ESA/Meteor Research Group/ CILBO/NASA/DLR/Cadmos.

Best regards, Orbiter.ch

New Observations Show Planet-forming Disc Torn Apart by its Three Central Stars













ALMA - Atacama Large Millimeter/submillimeter Array logo.

4 September 2020

The inner ring of GW Orionis: model and SPHERE observations

A team of astronomers have identified the first direct evidence that groups of stars can tear apart their planet-forming disc, leaving it warped and with tilted rings. This new research suggests exotic planets, not unlike Tatooine in Star Wars, may form in inclined rings in bent discs around multiple stars. The results were made possible thanks to observations with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) and the Atacama Large Millimeter/submillimeter Array (ALMA).

ALMA and SPHERE view of GW Orionis (side-by-side)

Our Solar System is remarkably flat, with the planets all orbiting in the same plane. But this is not always the case, especially for planet-forming discs around multiple stars, like the object of the new study: GW Orionis. This system, located just over 1300 light-years away in the constellation of Orion, has three stars and a deformed, broken-apart disc surrounding them.

ALMA and SPHERE view of GW Orionis (superimposed)

“Our images reveal an extreme case where the disc is not flat at all, but is warped and has a misaligned ring that has broken away from the disc,” says Stefan Kraus, a professor of astrophysics at the University of Exeter in the UK who led the research published today in the journal Science. The misaligned ring is located in the inner part of the disc, close to the three stars.

GW Orionis in the constellation of Orion

The new research also reveals that this inner ring contains 30 Earth-masses of dust, which could be enough to form planets. “Any planets formed within the misaligned ring will orbit the star on highly oblique orbits and we predict that many planets on oblique, wide-separation orbits will be discovered in future planet imaging campaigns, for instance with the ELT,” says team member Alexander Kreplin of the University of Exeter, referring to ESO’s Extremely Large Telescope, which is planned to start operating later this decade. Since more than half the stars in the sky are born with one or more companions, this raises an exciting prospect: there could be an unknown population of exoplanets that orbit their stars on very inclined and distant orbits.

Artistic animation of the warped and torn apart disc of GW Orionis

To reach these conclusions, the team observed GW Orionis for over 11 years. Starting in 2008, they used the AMBER and later the GRAVITY instruments on ESO’s VLT Interferometer in Chile, which combines the light from different VLT telescopes, to study the gravitational dance of the three stars in the system and map their orbits. “We found that the three stars do not orbit in the same plane, but their orbits are misaligned with respect to each other and with respect to the disc,” says Alison Young of the Universities of Exeter and Leicester and a member of the team.

Artistic animation of the stellar movements in GW Orionis

They also observed the system with the SPHERE instrument on ESO’s VLT and with ALMA, in which ESO is a partner, and were able to image the inner ring and confirm its misalignment. ESO’s SPHERE also allowed them to see, for the first time, the shadow that this ring casts on the rest of the disc. This helped them figure out the 3D shape of the ring and the overall disc.

The international team, which includes researchers from the UK, Belgium, Chile, France and the US, then combined their exhaustive observations with computer simulations to understand what had happened to the system. For the first time, they were able to clearly link the observed misalignments to the theoretical “disc-tearing effect”, which suggests that the conflicting gravitational pull of stars in different planes can warp and break their discs.

How GW Orionis got its ring (computer simulation)

Their simulations showed that the misalignment in the orbits of the three stars could cause the disc around them to break into distinct rings, which is exactly what they see in their observations. The observed shape of the inner ring also matches predictions from numerical simulations on how the disc would tear.

Interestingly, another team who studied the same system using ALMA believe another ingredient is needed to understand the system. “We think that the presence of a planet between these rings is needed to explain why the disc tore apart,” says Jiaqing Bi of the University of Victoria in Canada who led a study of GW Orionis published in The Astrophysical Journal Letters in May this year. His team identified three dust rings in the ALMA observations, with the outermost ring being the largest ever observed in planet-forming discs.

Future observations with ESO’s ELT and other telescopes may help astronomers fully unravel the nature of GW Orionis and reveal young planets forming around its three stars.

More information:

This research was presented in the paper “A triple star system with a misaligned and warped circumstellar disk shaped by disk tearing” to appear in Science (doi: 10.1126/science.aba4633).

https://science.sciencemag.org/cgi/doi/10.1126/science.aba4633

The team is composed of Stefan Kraus (University of Exeter, School of Physics & Astronomy, UK [Exeter]) Alexander Kreplin (Exeter), Alison K. Young (Exeter and School of Physics and Astronomy, University of Leicester, UK), Matthew R. Bate (Exeter), John D. Monnier (University of Michigan, USA [Michigan]), Tim J. Harries (Exeter), Henning Avenhaus (Max Planck Institute for Astronomy, Heidelberg, Germany), Jacques Kluska (Exeter and Instituut voor Sterrenkunde, KU Leuven, Belgium [KU Leuven]), Anna S. E. Laws (Exeter), Evan A. Rich (Michigan), Matthew Willson (Exeter and Georgia State University, USA), Alicia N. Aarnio (University of North Carolina Greensboro, USA), Fred C. Adams (Michigan), Sean M. Andrews (Center for Astrophysics | Harvard & Smithsonian, USA [CfA]), Narsireddy Anugu (Exeter, Michigan and Steward Observatory, University of Arizona, USA), Jaehan Bae (Michigan and Carnegie Institution for Science, Washington, USA), Theo ten Brummelaar (The CHARA Array of Georgia State University, California, USA), Nuria Calvet (Michigan), Michel Cure (Instituto de Fisica y Astronomia, Universidad de Valparaiso, Chile), Claire L. Davies (Exeter), Jacob Ennis (Michigan), Catherine Espaillat (Michigan and Boston University, USA), Tyler Gardner (Michigan), Lee Hartmann (Michigan), Sasha Hinkley (Exeter), Aaron Labdon (Exeter), Cyprien Lanthermann (KU Leuven), Jean-Baptiste LeBouquin (Michigan and Universite Grenoble Alpes, CNRS, IPAG, France), Gail H. Schaefer (CHARA), Benjamin R. Setterholm (Michigan), David Wilner (CfA), and Zhaohuan Zhu (University of Nevada, USA).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Links:

Research paper: https://www.eso.org/public/archives/releases/sciencepapers/eso2014/eso2014a.pdf

Interactive 3D model of the disc structure and stellar orbit of the GW Orionis triple system, as derived from the observations (Open with Acrobat Reader to display interactive elements properly): https://www.eso.org/public/archives/releases/pdf/eso2014a.pdf

Augmented reality representation of the GW Orionis triple system (via the National Radio Astronomy Observatory): https://public.nrao.edu/news/alma-discovers-misaligned-rings-in-planet-forming-disk-around-triple-stars/

Photos of the VLT: http://www.eso.org/public/images/archive/category/paranal/

Photos of ALMA: https://www.eso.org/public/images/archive/category/alma/

For scientists: got a story? Pitch your research: http://eso.org/sci/publications/announcements/sciann17277.html

Space Scoop kids's version of this press release: http://www.spacescoop.org/en/scoops/2034/tilted-wonder/

ESO’s VLT: https://www.eso.org/public/teles-instr/paranal-observatory/vlt/

ALMA: https://www.eso.org/public/teles-instr/alma/

SPHERE: https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/sphere/

Text: ESO/Bárbara Ferreira/Postdoctoral Research Associate, University of Leicester/Alison Young/Postdoctoral Research Fellow, University of Exeter/Alexander Kreplin/Associate Professor in Astrophysics, University of Exeter/Stefan Kraus/Images: ESO/L. Calçada, Exeter/Kraus et al./ALMA (ESO/NAOJ/NRAO), ESO/Exeter/Kraus et al./ESO/Exeter/Kraus et al., ALMA (ESO/NAOJ/NRAO)/IAU and Sky & Telescope/Videos: ESO/Exeter/Kraus et al./L. Calçada/Exeter/Kraus et al.

Best regards, Orbiter.ch

jeudi 3 septembre 2020

NASA's Chandra Opens Treasure Trove of Cosmic Delights













NASA - Chandra X-ray Observatory patch.

Sept. 3, 2020

Humanity has "eyes" that can detect all different types of light through telescopes around the globe and a fleet of observatories in space. From radio waves to gamma rays, this "multiwavelength" approach to astronomy is crucial to getting a complete understanding of objects in space.


Image above: This selection of images of different kinds of light from various missions and telescopes have been combined to better understand the universe. Each composite image contains X-ray data from Chandra as well as other telescopes. The objects represent a range of different astrophysical objects and include the galaxy Messier 82, the galaxy cluster Abell 2744, the supernova remnant 1987A, the binary star system Eta Carinae, the Cartwheel galaxy, and the planetary nebula Helix Nebula. Image Credits: NASA/CXC/SAO, NASA/STScI, NASA/JPL-Caltech/SSC, ESO/NAOJ/NRAO, NRAO/AUI/NSF, NASA/CXC/SAO/PSU, and NASA/ESA.

This compilation gives examples of images from different missions and telescopes being combined to better understand the science of the universe. Each of these images contains data from NASA's Chandra X-ray Observatory as well as other telescopes. Various types of objects are shown (galaxies, supernova remnants, stars, planetary nebulas), but together they demonstrate the possibilities when data from across the electromagnetic spectrum are assembled.

Top row, from left to right:

M82


Image above: Messier 82, or M82, is a galaxy that is oriented edge-on to Earth. This gives astronomers and their telescopes an interesting view of what happens as this galaxy undergoes bursts of star formation. X-rays from Chandra (appearing as blue and pink) show gas in outflows about 20,000 light years long that has been heated to temperatures above ten million degrees by repeated supernova explosions. Optical light data from NASA's Hubble Space Telescope (red and orange) shows the galaxy. Image Credits: X-ray: NASA/CXC; Optical: NASA/STScI.

Abell 2744


Image above: Galaxy clusters are the largest objects in the universe held together by gravity. They contain enormous amounts of superheated gas, with temperatures of tens of millions of degrees, which glows brightly in X-rays, and can be observed across millions of light years between the galaxies. This image of the Abell 2744 galaxy cluster combines X-rays from Chandra (diffuse blue emission) with optical light data from Hubble (red, green, and blue). Image Credits: NASA/CXC; Optical: NASA/STScI.

Supernova 1987A (SN 1987A)


Image above: On February 24, 1987, observers in the southern hemisphere saw a new object in a nearby galaxy called the Large Magellanic Cloud. This was one of the brightest supernova explosions in centuries and soon became known as Supernova 1987A (SN 87A). The Chandra data (blue) show the location of the supernova's shock wave — similar to the sonic boom from a supersonic plane — interacting with the surrounding material about four light years from the original explosion point. Optical data from Hubble (orange and red) also shows evidence for this interaction in the ring. Image Credits: Radio: ALMA (ESO/NAOJ/NRAO), P. Cigan and R. Indebetouw; NRAO/AUI/NSF, B. Saxton; X-ray: NASA/CXC/SAO/PSU/K. Frank et al.; Optical: NASA/STScI).

Bottom row, from left to right:

Eta Carinae


Image above: What will be the next star in our Milky Way galaxy to explode as a supernova? Astronomers aren't certain, but one candidate is in Eta Carinae, a volatile system containing two massive stars that closely orbit each other. This image has three types of light: optical data from Hubble (appearing as white), ultraviolet (cyan) from Hubble, and X-rays from Chandra (appearing as purple emission). The previous eruptions of this star have resulted in a ring of hot, X-ray emitting gas about 2.3 light years in diameter surrounding these two stars. Image Credits: NASA/CXC; Ultraviolet/Optical: NASA/STScI; Combined Image: NASA/ESA/N. Smith (University of Arizona), J. Morese (BoldlyGo Instituts) and A. Pagan).

Cartwheel Galaxy


Image above: This galaxy resembles a bull's eye, which is appropriate because its appearance is partly due to a smaller galaxy that passed through the middle of this object. The violent collision produced shock waves that swept through the galaxy and triggered large amounts of star formation. X-rays from Chandra (purple) show disturbed hot gas initially hosted by the Cartwheel galaxy being dragged over more than 150,000 light years by the collision. Optical data from Hubble (red, green, and blue) show where this collision may have triggered the star formation. Image Credits: X-ray: NASA/CXC; Optical: NASA/STScI).

Helix Nebula


Image above: When a star like the Sun runs out of fuel, it expands and its outer layers puff off, and then the core of the star shrinks. This phase is known as a "planetary nebula," and astronomers expect our Sun will experience this in about 5 billion years. This Helix Nebula images contains infrared data from NASA's Spitzer Space Telescope (green and red), optical light from Hubble (orange and blue), ultraviolet from NASA's Galaxy Evolution Explorer (cyan), and Chandra's X-rays (appearing as white) showing the white dwarf star that formed in the center of the nebula. The image is about four light years across. Image Credits: X-ray: NASA/CXC; Ultraviolet: NASA/JPL-Caltech/SSC; Optical: NASA/STScI(M. Meixner)/ESA/NRAO(T.A. Rector); Infrared: NASA/JPL-Caltech/K. Su).

Three of these images — SN 1987A, Eta Carinae, and the Helix Nebula — were developed as part of NASA's Universe of Learning (UoL), an integrated astrophysics learning and literacy program, and specifically UoL's ViewSpace project. The UoL brings together experts who work on Chandra, the Hubble Space Telescope, Spitzer Space Telescope, and other NASA astrophysics missions.

Chandra X-ray Observatory. Animation Credits: NASA/CXC

NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science from Cambridge Massachusetts and flight operations from Burlington, Massachusetts.

Read more from NASA's Chandra X-ray Observatory: https://chandra.harvard.edu/photo/2020/archives/

For more Chandra images, multimedia and related materials, visit:
https://www.nasa.gov/mission_pages/chandra/main/index.html

Related links:

NASA's Universe of Learning (UoL): https://www.universe-of-learning.org/

ViewSpace: https://viewspace.org/interactives/unveiling_invisible_universe/star_death/helix_nebula

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Lee Mohon/Marshall Space Flight Center/Molly Porter/Chandra X-ray Center/Megan Watzke.

Greetings, Orbiter.ch

The ALICE TPC is upgraded













CERN - European Organization for Nuclear Research logo.

September 3, 2020

The refurbished detector was lowered into the ALICE cavern and installed in the experiment in August

The ALICE TPC being tested in its clean room in May 2020 (Image: CERN)

“One more centimetre,” said the chief technician, while operating the hydraulic jack system on 14 August. The 5-m-diameter, 5-m-long cylindrical detector gently slid into the parking position, 56 metres below the ground in the ALICE cavern at LHC Point 2, where it will stand for some time. This operation culminates the many-years-long upgrade of ALICE’s Time Projection Chamber (TPC), the large tracking device of the LHC’s heavy-ion specialist.

The ALICE TPC is a big, gas-filled cylinder with a hole in the centre – to accommodate the silicon tracker as well as the beam pipe – where the charge produced by ionising radiation is projected onto detectors arranged in the two endplates. These detectors used to be multi-wire proportional chambers, 72 in total, which have now been replaced by detectors based on Gas Electron Multipliers (GEM), a micro-pattern structure developed at CERN. These new devices, together with new readout electronics that feature a continuous readout mode, will allow ALICE to record the information of all tracks produced in lead–lead collisions at rates of 50 kHz, producing data at a staggering rate of 3.5 TB/s. The average load on the chambers under these conditions is expected to be as high as 10 nA/cm², and the GEM detectors are able to cope with this. But will these new devices perform as nicely as their predecessors?

In order to answer this question, several years of intensive R&D were necessary, since the large number of positive ions produced at the detectors would lead to excessive track distortions. This, combined with the necessity of keeping excellent energy-loss (dE/dx) resolution for particle identification, and the imperative robustness against discharges, posed an exciting challenge that led to a novel configuration of GEM-based detectors.

The TPC being lowered down the shaft to the experimental cavern (Images: CERN)

As the fabrication of over 800 GEM foils was taking place at the CERN PCB workshop, the new chambers and electronics were being constructed and thoroughly tested around the world – quite a logistic exercise. The ALICE team proceeded with the final steps of the upgrade process during the ongoing second long shutdown of CERN’s accelerator complex (LS2). First, the TPC was extracted from the underground cavern and brought, inside its blue frame, to a large clean room at the surface. Cranes, jacks and a huge truck were used for careful transportation. The chamber replacement, electronics installation and tests with a laser system, cosmic rays and X-rays took over a year. In July 2020, the TPC was declared ready for being re-installed in the cavern. Cranes, truck and jacks once again.

ALICE achieved a major milestone with the completion of the TPC upgrade, after many years of intense R&D, construction and assembly. At the end of 2020, all the services will be connected and the full, upgraded TPC will be operated and commissioned together with all other detectors in the experiment. The real excitement will be when the first post-LS2 collisions from the LHC are delivered.

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 23 Member States.

Related links:

ALICE: https://home.cern/science/experiments/alice

LHC’s heavy-ion: https://home.cern/science/physics/heavy-ions-and-quark-gluon-plasma

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

Images (mentioned), Text, Credits: CERN/Chilo Garabatos.

Best regards, Orbiter.ch

Heart Studies, AC and Plumbing Work Fill Orbital Schedule













ISS - Expedition 63 Mission patch.

September 3, 2020

The three-person Expedition 63 crew focused its attention today on Japanese science hardware and Russian cardiac studies. The International Space Station trio also serviced air conditioning and plumbing systems.

The Kibo laboratory module from JAXA (Japan Aerospace Exploration Agency) enables a multitude of space science taking place both inside and outside the orbital lab. Kibo has an airlock that the crew can place external experiments and even satellites for deployment into the vacuum of space.


Image above: An space station crew member photographed the well-lit, highly populated areas of Pakistan and northern India during an orbital night period. Image Credit: NASA.

Commander Chris Cassidy spent the first part of Thursday removing a commercial science payload from Kibo’s airlock. The NanoRacks External Platform supports a variety of research requiring exposure to the space environment. The automated science experiments look at different technologies and phenomena including robotics, physics, and microbiology that can benefit Earth and space industries.

Cassidy switched roles in the afternoon from space scientist to orbital maintenance man. The veteran NASA astronaut checked out spacecraft atmosphere monitor components and updated software supporting the Waste and Hygiene Compartment, the station’s restroom.

External view of International Space Station. Animation Credit: ISS HD Live Now

Roscosmos cosmonauts Anatoly Ivanishin and Ivan Vagner continued a second day of heart research to understand how the human body adapts to long-term weightlessness. The duo explored the benefits of a negative pressure lower body suit that prevents blood and body fluids from pooling toward an astronaut’s head, a unique space condition commonly known as “puffy face.”

Ivanishin also replaced battery components before setting up advanced Earth photography gear. Vagner worked on fluid transfers throughout the station’s Russian segment then moved on and updated lab inventory files.

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

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

NanoRacks External Platform: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1085

Heart research: https://www.energia.ru/en/iss/researches/human/10.html

Negative pressure lower body suit: https://blogs.nasa.gov/ISS_Science_Blog/2015/06/02/rubber-vacuum-pants-that-suck/

Advanced Earth photography: https://www.energia.ru/en/iss/researches/study/09.html

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

New Gears Can Withstand Impact, Freezing Temperatures During Lunar Missions








NASA Langley Research Center logo.

Sept. 3, 2020

Many exploration destinations in our solar system are frigid and require hardware that can withstand the extreme cold. During NASA’s Artemis missions, temperatures at the Moon’s South Pole will drop drastically during the lunar night. Farther into the solar system, on Jupiter’s moon Europa, temperatures never rise above -260 degrees Fahrenheit (-162 degrees Celsius) at the equator.


Image above: Andrew Kennett (left) watches as Dominic Aldi (right) uses liquid nitrogen to cool a motor integrated bulk metallic glass gearbox prior to shock testing it. The motor and gearbox are inside the frosty metal “bucket” that contains the liquid nitrogen. The tooling, including the “bucket” is designed to be mounted both vertically (shown) and horizontally on the cube for testing the motor and gearbox in three orientations. Image Credits: NASA/JPL-Caltech.

One NASA project is developing special gears that can withstand the extreme temperatures experienced during missions to the Moon and beyond. Typically, in extremely low temperatures, gears – and the housing in which they’re encased, called a gearbox – are heated. After heating, a lubricant helps the gears function correctly and prevents the steel alloys from becoming brittle and, eventually, breaking. NASA’s Bulk Metallic Glass Gears (BMGG) project team is creating material made of “metallic glass” for gearboxes that can function in and survive extreme cold environments without heating, which requires energy. Operations in cold and dim or dark environments are currently limited due to the amount of available power on a rover or lander.

The BMGG unheated gearboxes will reduce the overall power needed for a rover or lander’s operations, such as pointing antennas and cameras, moving robotic arms, handling and analyzing samples, and mobility (for a rover). The power saved with the BMGG gearbox could extend a mission or allow for more instruments.


Image above: The motor and gearbox are mounted for testing in one of two horizontal orientations. Frost forms on the surface of the “bucket” when liquid nitrogen is used to cool the hardware to the test temperature of -279 degrees Fahrenheit (-173 degrees Celsius). Image Credits: NASA/JPL-Caltech.

The team recently tested the gears at NASA's Jet Propulsion Laboratory in Southern California. At JPL's Environmental Test Laboratory, engineers mounted the motor and gearbox on a tunable beam designed to measure the response an item has to a shock, or forceful impact. Team members then used liquid nitrogen to cool the gears down to roughly to -279 degrees Fahrenheit (-173 degrees Celsius). Next, they fired a cylindrical steel projectile at the beam to simulate a “shock event.” Shock testing is used to ensure spacecraft hardware will not break during events that cause a sudden jolt, such as the release of an antenna or what a spacecraft experiences during entry, descent, and landing. The test simulated how the bulk metallic glass gears might behave when collecting a regolith sample during the lunar night – which spans roughly 14 days on Earth – or deploying a science instrument on an ocean world in our solar system.

“Before NASA sends hardware like gearboxes, particularly those made with new materials, to extremely cold environments, we want to make sure they will not be damaged by the stressful events that occur during the life of a mission,” said Peter Dillon, BMGG project manager at JPL. “This shock testing simulates the stresses of entry, descent, and landing, and potential surface operations.”

Before each shock test, a team member poured liquid nitrogen over the motor and gearbox contained in a “bucket.” Liquid nitrogen, which boils at -320 degrees Fahrenheit (-196 degrees Celsius), brought the gearbox’s temperature below -279 degrees Fahrenheit (-173 degrees Celsius). The liquid nitrogen drained and, within a few seconds, a steel impactor fired at a steel beam on which the motor and gearbox were mounted. The team then ran the motor to drive the gearbox to determine whether or not the shock event had damaged the gearbox and its motor. The team monitored the electrical current required to run the motor and listened for any irregular sounds that indicated damage. The motor and gearbox were shock tested twice in three different orientations. Each test demonstrated that the gears could withstand a “shock event” at a temperature as low as -279 degrees Fahrenheit (-173 degrees Celsius).


Image above: The shock for the test is generated by launching a steel mass (one of the round cylinders in the lower left of the image) into the bottom of the long steel beam. The large clamps set the length of the beam that can “ring” from the impact. By changing the clamp position the profile of the shock can be tuned, hence the name “tunable beam.” The large cube mounted to the beam simplifies mounting of hardware for testing. The shock event is captured using an accelerometer mounted at the hardware. Image Credits: NASA/JPL-Caltech.

“This is an exciting event as it demonstrates both the mechanical resilience of the bulk metallic glass alloy and the design of the gearbox,” Dillon said. “These gears could help enable potential operations during the lunar night, in permanently shadowed lunar craters, in polar regions on the Moon, and on ocean worlds.”

The BMGG team will perform additional cold temperature testing next year to qualify the gears for use in future NASA missions.

Learn more about the BMGG project:

https://www.nasa.gov/directorates/spacetech/game_changing_development/projects/BMGG/

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

Images (mentioned), Text, Credits: NASA/Eric Vitug/Langley Research Center/Hillary Smith.

Greetings, Orbiter.ch

International Space Station Research on Tiny Colloid Particles Yields Big Results













ISS - International Space Station logo.

Sept. 3, 2020

Toothpaste, 3D printing, pharmaceuticals, and detecting shifting sands on Mars may not seem related to each other at all. Yet each stands to benefit from improvements made thanks to years of research on colloids aboard the International Space Station.

Mixtures of tiny particles suspended in a liquid, colloids occur in many forms. These include natural mixtures such as milk and muddy water as well as a range of manufactured products from shampoo to medicine to salad dressing. Some colloids contain unique particles capable of forming crystals that assemble into new materials.


Image above: NASA astronaut Jessica Meir configures the Light Microscopy Module (LMM) for Advanced Colloids Experiment-Temperature-4 (ACE-T-4), which examines the transition of an ordered crystal to a disordered glass to determine how increasing disorder affects structural and dynamic properties. Image Credit: NASA.

Humans have continuously lived and worked aboard the space station for nearly 20 years. Researchers have used the orbiting lab for almost that long to better understand the behavior of colloids – both to improve products used in our everyday lives and create entirely new ones, including some that could enable exploration farther into space. These experiments have advanced understanding of basic physics as well.

Studying colloids on Earth is complicated by gravity, which causes some particles to rise and others to sink. Microgravity takes away that complication and makes possible research that can help companies design better products. Procter & Gamble (P&G) researcher Matthew Lynch says the basic research is of interest to the academic community as well. For example, the relationship between the shapes of particles and how they interact contributes to the creation of new materials.


Image above: Canadian Space Agency (CSA) astronaut Chris Hadfield sets up Binary Colloidal Alloy Test (BCAT) Session 1 during Expedition 34. Image Credit: NASA.

The long list of colloid research on the space station includes Binary Colloidal Alloy Tests (BCAT), a series of more than 40 experiments that began in 2004. Many BCAT experiments looked at phase separation, the point at which a mixture separates, which plays a role in product quality and shelf life.

The list also includes ongoing Advanced Colloid Experiments (ACE), with more than a dozen investigations to date. The ACE series has examined the behavior of different types of particles and how different conditions affect the way particles form 3D crystals. Understanding this process and learning to control it could improve 3D printing, for example, and make possible the creation of advanced optical materials.


Image above: NASA astronaut Karen Nyberg works on an Advanced Colloids Experiment (ACE) investigation to help researchers understand how to optimize stabilizers and extend the shelf life of products like laundry detergent, paint, and ketchup. Image Credit: NASA.

ACE research also tackled a basic challenge: how to keep a product liquid enough to dispense easily and yet prevent ingredients, or particles, from clumping together and settling. That process, called coarsening, turns a creamy shampoo into a layer of gooey solids and watery liquid.

“It is easy enough to do one or the other,” Lynch says. “I could suspend something in concrete and it would stay suspended, but then the product has to somehow dispense. Doing both is not a trivial problem.”

Some two-thirds of P&G’s biggest brands could benefit from colloids research, according to Lynch, and space station research has contributed to three new patents for the company. With annual sales for its Downy fabric softener alone totaling about $4 billion, Lynch points out that even a one percent savings in production costs or a slightly longer shelf life becomes significant. Long-term space exploration, such as a years-long trip to Mars, stands to benefit from extended product shelf-life as well.

Better 3D printing or additive manufacturing also is a capability critical for future long-term space missions.

NASA Takes First 3-D Microscopic Image on the Space Station

Video above: A composite 3-D model of NASA's Advanced Colloids Experiment (ACE). Video Credits: P&G, NASA, ISS National Lab.

“On a long space voyage, an engine part will fail, and you might not take along a spare,” says Paul Chaikin, a physics professor at New York University and principal investigator on several ACE investigations. Understanding how particle shape, size, and packing behavior affect this process is key to using colloids in additive manufacturing to make those spare parts.

The work also explores the feasibility of creating particles that come together on their own, using different forms of energy to instruct the particles exactly how to bind together so they create materials with specific properties. Future explorers could take along these particles as the building blocks to make almost anything they need.

Colloid research aboard the orbiting laboratory also helped scientists develop a technique using light scattering to observe how particles stick together to form rigid networks. This technique can reveal properties of the surface of a planet as well, possibly detecting landslides on Mars, for example. In addition, it could help predict structural failure of roads and bridges and even earthquakes.

The addition of a confocal microscope in the station’s Light Microscopy Module (LMM) in 2009 greatly enhanced colloid research. With a conventional microscope, light travels as far into a specimen as it can penetrate. A confocal microscope focuses a beam of light at one narrow slice of a specimen at a time, capturing multiple 2D images that can then be used to create a 3D structure.

International Space Station (ISS). Animation Credit: NASA

“The confocal capability is critical,” Lynch says. “Without it, you can see the colloids, but you get no depth, and it is very difficult to pull out the physics. LMM has the resolution to identify where things are and the dynamics of the system.”

All of these advances would have been much more difficult, if not impossible, without access to the space station.

“A lot of our understanding of colloids came from these experiments in microgravity,” Chaikin says. “Getting rid of gravity was really important in allowing us to isolate different effects. It essentially made this field.”

NASA’s Glenn Research Center in Cleveland oversees both BCAT and ACE, and the ISS U.S. National Lab has sponsored several individual investigations. The Biological and Physical Sciences (BPS) Division of NASA’s Science Mission Directorate at NASA Headquarters in Washington also sponsors ACE investigations as part of its mission to conduct fundamental science.

Related links:

Binary Colloidal Alloy Tests (BCAT): https://www1.grc.nasa.gov/space/iss-research/mwa/bcat/

Advanced Colloid Experiments (ACE): https://www1.grc.nasa.gov/space/iss-research/iss-fcf/fir/lmm/ace/

Light Microscopy Module (LMM): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=531

Biological and Physical Sciences (BPS): https://science.nasa.gov/biological-physical

ISS National Lab: https://www.issnationallab.org/

Spot the Station: https://spotthestation.nasa.gov/

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

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

Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Research Office/Melissa Gaskill.

Greetings, Orbiter.ch

SpaceX Starlink 11 launch













SpaceX - Falcon 9 / Starlink Mission patch.

Sep. 3, 2020

Falcon 9 carrying Starlink 11 lift off

A SpaceX Falcon 9 rocket launched 60 Starlink satellites (Starlink-11) from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida, on 3 September 2020, at 12:46 UTC (08:46 EDT).

SpaceX Starlink 11 launch & Falcon 9 first stage landing, 3 September 2020

Following stage separation, Falcon 9’s first stage (B1060) landed on the “Of Course I Still Love You” drone-ship, stationed in the Atlantic Ocean. Falcon 9’s first stage previously launched the GPS III Space Vehicle 03 mission in June 2020.

Falcon 9’s first stage (B1060) landed on the “Of Course I Still Love You” drone-ship

A SpaceX Falcon 9 rocket launches the 12th batch of approximately 60 satellites for SpaceX’s Starlink broadband network, a mission designated Starlink 11. Delayed from Aug. 29 and Sept. 1.

Related articles:

SpaceX Starlink 10 launch
https://orbiterchspacenews.blogspot.com/2020/08/spacex-starlink-10-launch.html

Starlink satellites: a helpless Switzerland
https://orbiterchspacenews.blogspot.com/2020/08/starlink-satellites-helpless-switzerland.html

SpaceX Starlink 9 launched in to orbit
https://orbiterchspacenews.blogspot.com/2020/08/spacex-starlink-9-launched-in-to-orbit.html

SpaceX Starlink 7 launch success
https://orbiterchspacenews.blogspot.com/2020/06/spacex-starlink-7-launch-success.html

SpaceX - Starlink 6 launched into orbit
https://orbiterchspacenews.blogspot.com/2020/04/spacex-starlink-6-launched-into-orbit.html

SpaceX Starlink 5 launched
https://orbiterchspacenews.blogspot.com/2020/03/spacex-starlink-5-launched.html

SpaceX Starlink 4 launched
https://orbiterchspacenews.blogspot.com/2020/02/spacex-starlink-launched.html

SpaceX - Starlink 3 launch success
https://orbiterchspacenews.blogspot.com/2020/01/spacex-starlink-3-launch-success.html

SpaceX - SpaceX Starlink 2 launch Success
https://orbiterchspacenews.blogspot.com/2020/01/spacex-spacex-starlink-2-launch-success.html

Panic wind among astronomers
https://orbiterchspacenews.blogspot.com/2019/05/panic-wind-among-astronomers.html

SpaceX Starlink launched
https://orbiterchspacenews.blogspot.com/2019/11/spacex-starlink-launched.html

Related link:

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

Images, Video, Text, Credits: Credits: SpaceX/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

The Moon Is Rusting, and Researchers Want to Know Why














ISRO - Chandrayaan-1 Mission patch / JPL - Jet Propulsion Laboratory logo.

September 3, 2020

While our Moon is airless, research indicates the presence of hematite, a form of rust that normally requires oxygen and water. That has scientists puzzled.


Image above: The blue areas in this composite image from the Moon Mineralogy Mapper (M3) aboard the Indian Space Research Organization's Chandrayaan-1 orbiter show water concentrated at the Moon's poles. Homing in on the spectra of rocks there, researcher found signs of hematite, a form of rust. Image Credits: ISRO/NASA/JPL-Caltech/Brown University/USGS.

Mars has long been known for its rust. Iron on its surface, combined with water and oxygen from the ancient past, give the Red Planet its hue. But scientists were recently surprised to find evidence that our airless Moon has rust on it as well.

A new paper in Science Advances reviews data from the Indian Space Research Organization's Chandrayaan-1 orbiter, which discovered water ice and mapped out a variety of minerals while surveying the Moon's surface in 2008. Lead author Shuai Li of the University of Hawaii has studied that water extensively in data from Chandrayaan-1's Moon Mineralogy Mapper instrument, or M3, which was built by NASA's Jet Propulsion Laboratory in Southern California. Water interacts with rock to produce a diversity of minerals, and M3 detected spectra - or light reflected off surfaces - that revealed the Moon's poles had a very different composition than the rest of it.

Intrigued, Li homed in on these polar spectra. While the Moon's surface is littered with iron-rich rocks, he nevertheless was surprised to find a close match with the spectral signature of hematite. The mineral is a form of iron oxide, or rust, produced when iron is exposed to oxygen and water. But the Moon isn't supposed to have oxygen or liquid water, so how can it be rusting?

Metal Mystery

The mystery starts with the solar wind, a stream of charged particles that flows out from the Sun, bombarding Earth and the Moon with hydrogen. Hydrogen makes it harder for hematite to form. It's what is known as a reducer, meaning it adds electrons to the materials it interacts with. That's the opposite of what is needed to make hematite: For iron to rust, it requires an oxidizer, which removes electrons. And while the Earth has a magnetic field shielding it from this hydrogen, the Moon does not.

"It's very puzzling," Li said. "The Moon is a terrible environment for hematite to form in." So he turned to JPL scientists Abigail Fraeman and Vivian Sun to help poke at M3's data and confirm his discovery of hematite.

The Moon. Animation Credit: NASA

"At first, I totally didn't believe it. It shouldn't exist based on the conditions present on the Moon," Fraeman said. "But since we discovered water on the Moon, people have been speculating that there could be a greater variety of minerals than we realize if that water had reacted with rocks."

After taking a close look, Fraeman and Sun became convinced M3's data does indeed indicate the presence of hematite at the lunar poles. "In the end, the spectra were convincingly hematite-bearing, and there needed to be an explanation for why it's on the Moon," Sun said.

Three Key Ingredients

Their paper offers a three-pronged model to explain how rust might form in such an environment. For starters, while the Moon lacks an atmosphere, it is in fact home to trace amounts of oxygen. The source of that oxygen: our planet. Earth's magnetic field trails behind the planet like a windsock. In 2007, Japan's Kaguya orbiter discovered that oxygen from Earth's upper atmosphere can hitch a ride on this trailing magnetotail, as it's officially known, traveling the 239,000 miles (385,00 kilometers) to the Moon.

That discovery fits with data from M3, which found more hematite on the Moon's Earth-facing near side than on its far side. "This suggested that Earth's oxygen could be driving the formation of hematite," Li said. The Moon has been inching away from Earth for billions of years, so it's also possible that more oxygen hopped across this rift when the two were closer in the ancient past.

Then there's the matter of all that hydrogen being delivered by the solar wind. As a reducer, hydrogen should prevent oxidation from occurring. But Earth's magnetotail has a mediating effect. Besides ferrying oxygen to the Moon from our home planet, it also blocks over 99% of the solar wind during certain periods of the Moon's orbit (specifically, whenever it's in the full Moon phase). That opens occasional windows during the lunar cycle when rust can form.

Artist's conception of lunar probe Chandrayaan-1. Image Credit: ISRO

The third piece of the puzzle is water. While most of the Moon is bone dry, water ice can be found in shadowed lunar craters on the Moon's far side. But the hematite was detected far from that ice. The paper instead focuses on water molecules found in the lunar surface. Li proposes that fast-moving dust particles that regularly pelt the Moon could release these surface-borne water molecules, mixing them with iron in the lunar soil. Heat from these impacts could increase the oxidation rate; the dust particles themselves may also be carrying water molecules, implanting them into the surface so that they mix with iron. During just the right moments - namely, when the Moon is shielded from the solar wind and oxygen is present - a rust-inducing chemical reaction could occur.

More data is needed to determine exactly how the water is interacting with rock. That data could also help explain another mystery: why smaller quantities of hematite are also forming on the far side of the Moon, where the Earth's oxygen shouldn't be able to reach it.

More Science to Come

Fraeman said this model may also explain hematite found on other airless bodies like asteroids. "It could be that little bits of water and the impact of dust particles are allowing iron in these bodies to rust," she said.

Li noted that it's an exciting time for lunar science. Almost 50 years since the last Apollo landing, the Moon is a major destination again. NASA plans to send dozens of new instruments and technology experiments to study the Moon beginning next year, followed by human missions beginning in 2024 all as part of the Artemis program.

JPL is also building a new version of M3 for an orbiter called Lunar Trailblazer. One of its instruments, the High-resolution Volatiles and Minerals Moon Mapper (HVM3), will be mapping water ice in permanently shadowed craters on the Moon, and may be able to reveal new details about hematite as well.

"I think these results indicate that there are more complex chemical processes happening in our solar system than have been previously recognized," Sun said. "We can understand them better by sending future missions to the Moon to test these hypotheses."

Related links:

Chandrayaan-1: https://www.isro.gov.in/Spacecraft/chandrayaan-1

Jet Propulsion Laboratory (JPL): https://www.jpl.nasa.gov/

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Alana Johnson/Grey Hautaluoma/JPL/Andrew Good.

Greetings, Orbiter.ch