samedi 14 septembre 2019

NASA Funds CubeSat Pathfinder Mission to Unique Lunar Orbit












NASA logo.

Sept. 14, 2019

NASA has awarded a $13.7 million contract to Advanced Space of Boulder, Colorado, to develop and operate a CubeSat mission to the same lunar orbit targeted for Gateway – an orbiting outpost astronauts will visit before descending to the surface of the Moon in a landing system as part of NASA’s Artemis program.

The Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) is expected to be the first spacecraft to operate in a near rectilinear halo orbit around the Moon. In this unique orbit, the CubeSat will rotate together with the Moon as it orbits Earth and will pass as close as 1,000 miles and as far as 43,500 miles from the lunar surface.


Animation above: Highly elliptical, a near rectilinear halo orbit around the Moon takes advantage of a precise balance point in the gravities of Earth and the Moon and creates a stability that is ideal for long-term missions like Gateway. Animation Credit: Advanced Space.

The pathfinder mission represents a rapid lunar flight demonstration and could launch as early as December 2020. CAPSTONE will demonstrate how to enter into and operate in this orbit as well as test a new navigation capability. This information will help reduce logistical uncertainty for Gateway, as NASA and international partners work to ensure astronauts have safe access to the Moon’s surface. It will also provide a platform for science and technology demonstrations.

“This is an exciting opportunity for NASA to aggressively push forward towards the Moon in partnership with several American small businesses as a vanguard to Artemis and sustained human presence beyond low-Earth orbit,” said Jim Reuter, associate administrator for NASA’s Space Technology Mission Directorate. “This mission is highly ambitious in both cost and schedule – and taking that deliberate risk is part of the objective of this mission – alongside the rapid technological advancement in cislunar navigation and the opportunity to verify orbital trajectory assumptions and retire unknowns for future missions.”

The 12-unit CubeSat is about the size of a small microwave oven. Onboard is a communications system capable of determining how far CAPSTONE is from NASA’s Lunar Reconnaissance Orbiter and how fast the distance between the two spacecraft is changing. The inter-spacecraft information will be used to demonstrate software for autonomous navigation, allowing future missions to determine their location without having to rely exclusively on tracking from Earth.

CAPSTONE will provide NASA and its partners with important insights to support exploration of the Moon and Mars, including:

- Demonstration of spacecraft-to-spacecraft navigation services

- Verification of near rectilinear halo orbit characteristics for future spacecraft

- Experience entering this orbit with a highly efficient lunar transfer

- Experience with rideshare or small dedicated launches to the Moon

- Commercial experience providing mission planning and operations support services for CubeSats beyond Earth

- Rapid commercial delivery of a CubeSat mission beyond Earth orbit

“CAPSTONE offers a lot in a small package,” said Advanced Space CEO Bradley Cheetham. “Not only will it serve as a pathfinder for Artemis, but it will also demonstrate key exploration-enabling commercial capabilities. Our team will be pioneering state-of-the-art tools for mission planning and operations to enable growth in the number of future missions to the Moon, Mars, and throughout the solar system.”

A number of launch options are possible for the mission, including being the primary payload on a small spacecraft launch vehicle. After launch, CAPSTONE will take approximately three months to enter its target orbit and begin a six-month primary demonstration phase to understand operations in this unique regime.


Image above: Illustration of the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE). Image Credit: Tyvak Nano-Satellite Systems.

The award to Advanced Space is through a Phase III Small Business Innovation Research (SBIR) contract, a follow-on to earlier SBIR awards that developed CAPSTONE’s autonomous positioning and navigation system experiment.

The CAPSTONE team includes Advanced Space and Tyvak Nano-Satellite Systems, Inc. of Irvine, California. The project is managed by NASA’s Small Spacecraft Technology (SST) program within the agency’s Space Technology Mission Directorate. Based at NASA's Ames Research Center in California’s Silicon Valley, SST expands U.S. capability to execute unique missions through rapid development and demonstration of capabilities for small spacecraft applicable to exploration, science and the commercial space sector. Advanced Exploration Systems (AES) within NASA’s Human Exploration and Operations Mission Directorate will fund the launch and support mission operations. AES engages in activities focused on advanced design, development, and demonstration of exploration capabilities to reduce risk, lower life cycle cost and validate operational concepts for future human missions.

NASA’s Artemis lunar exploration program includes sending a suite of new science instruments and technology demonstrations to study the Moon, landing the first woman and next man on the lunar surface by 2024, and establishing a sustained presence by 2028. The agency will leverage its Artemis experience and technologies to prepare for the next giant leap – sending astronauts to Mars.

To learn more about NASA’s Artemis program and Moon to Mars exploration approach, visit:

https://www.nasa.gov/moontomars

To learn more about NASA's investments in space technology, visit:

https://www.nasa.gov/spacetech

To learn more about Advanced Space and the Cislunar Autonomous Positioning System, visit:

https://advancedspace.com/caps/

Animation (mentioned), Image (mentioned), Text, Credits: NASA/Sean Potter/Clare Skelly/Ames Research Center/Alison Hawkes​.

Greetings, Orbiter.ch

vendredi 13 septembre 2019

Biological, Materials Sciences and Inspiration Reign Supreme at End of Workweek













ISS - Expedition 60 Mission patch.

September 13, 2019

The crew of Expedition 60 devoted their Friday to working on groundbreaking scientific research aboard the International Space Station, as well as inspiring the Artemis generation during a downlink hosted by the National STEM Cell Foundation.

Flight Engineers Nick Hague and Andrew Morgan of NASA took the mantle of fielding selected questions from 39 middle school classrooms nationwide during the space-to-Earth call at 10:55 a.m. EDT. The downlink, hosted by the National STEM Cell Foundation at the Kentucky Science Center, allowed classes that are part of the National STEM Scholar Program to get a firsthand look at what it’s like to live and work in microgravity, with the crewmates providing anecdotes from their time in space.


Image above: Expedition 60 Flight Engineer Christina Koch of NASA conducts research for a protein crystal growth experiment in the Kibo Japanese Experiment Module (JEM). The research investigates the production of antibody therapies with a longer shelf-life to benefit humans on Earth and in space. Image Credit: NASA.

Hague and Morgan, along with NASA astronaut Christina Koch and Luca Parmitano of (European Space Agency), further investigated the effects of spaceflight on rodent residents with Rodent Research-17, evaluating the changes caused by microgravity to their immunity, cells, bones and musculature. These findings will bolster discoveries for new therapies — both in space and back on Earth.

Koch also performed experiment maintenance, installing a sample cartridge into the Cryo Chiller within an Expedite the Processing of Experiments to Space Station (EXPRESS) locker. This unique chiller provides rapid freezing capability in support of biological sciences, as well as temperature-controlled transfer to and from the space station on visiting vehicles.

International Space Station (ISS). Image Credit: NASA

Hague and Koch captured cinematic recordings of Morgan working on the Microgravity Crystals experiment for ISS Experience, a virtual reality series will educate to Earth audiences on what Expedition crew members do each day in support of operations and research. The experiment will illustrate how microgravity can be helpful in learning about diseases on Earth through the crystallization of a membrane protein integral to tumor growth and cancer survival. While the crystallization of this protein has yielded unsatisfactory results in gravity, Microgravity Crystals leverages the absence of gravity for extensive protein crystallization work onboard, significantly increasing the likelihood of successful crystal growth. Forthcoming results may support the development of cancer treatments that target the protein more effectively, and with fewer side effects.

Commander Alexey Ovchinin of Roscosmos joined his American teammates in conducting routine eye ultrasounds. Since long-duration space missions have been shown to cause severe and lasting physical damage to some astronauts’ eyes, continued monitoring of eye health is necessary to mitigate any noticeable effects for the crew.

Related links:

Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html

Rodent Research-17: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7992

Cryo Chiller: https://iss-www.jsc.nasa.gov/pst/External_v2/Facility.html#id=7466

Microgravity Crystals: https://iss-www.jsc.nasa.gov/pst/External_v2/Investigation.html#id=7977

ISS Experience: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7877

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/Catherine Williams.

Best regards, Orbiter.ch

VISTA unveils a new image of the Large Magellanic Cloud













ESO - European Southern Observatory logo.

13 September 2019

The Large Magellanic Cloud revealed by VISTA

ESO’s VISTA telescope reveals a remarkable image of the Large Magellanic Cloud, one of our nearest galactic neighbours. VISTA has been surveying this galaxy and its sibling the Small Magellanic Cloud, as well as their surroundings, in unprecedented detail. This survey allows astronomers to observe a large number of stars, opening up new opportunities to study stellar evolution, galactic dynamics, and variable stars.

Highlights of the Large Magellanic Cloud

The Large Magellanic Cloud, or LMC, is one of our nearest galactic neighbors, at only 163 000 light years from Earth. With its sibling the Small Magellanic Cloud, these are among the nearest dwarf satellite galaxies to the Milky Way. The LMC is also the home of various stellar conglomerates and is an ideal laboratory for astronomers to study the processes that shape galaxies.

Large Magellanic Cloud

ESO’s VISTA telescope, has been observing these two galaxies for the last decade. The image presented today is the result of one of the many surveys that astronomers have performed with this telescope. The main goal of the VISTA Magellanic Clouds (VMC) Survey has been to map the star formation history of the Large and Small Magellanic Clouds, as well as their three-dimensional structures.

Zooming on the Large Magellanic Cloud

VISTA was key to this image because it observes the sky in near-infrared wavelengths of light. This allows it to see through clouds of dust that obscure parts of the galaxy. These clouds block a large portion of visible light but are transparent at the longer wavelengths VISTA was built to observe. As a result, many more of the individual stars populating the centre of the galaxy are clearly visible. Astronomers analysed about 10 million individual stars in the Large Magellanic Cloud in detail and determined their ages using cutting-edge stellar models[1]. They found that younger stars trace multiple spiral arms in this galaxy.

Comparison of the Large Magellanic Cloud in infrared and visible light

For millennia, the Magellanic Clouds have fascinated people in the Southern Hemisphere, but they were largely unknown to Europeans until the Age of Discovery. The name we use today harkens back to the explorer Ferdinand Magellan, who 500 years ago began the first circumnavigation of the Earth. The records the expedition brought back to Europe revealed many places and things to Europeans for the first time.

Comparison of the Tarantula nebula in infrared and visible light

The spirit of exploration and discovery is ever more live today in the work of astronomers around the world, including the VMC Survey team whose observations led to this stunning image of the LMC.

Panning across the Large Magellanic Cloud

Notes:

[1] Stellar models allow astronomers to predict the life and death of stars, providing insights into properties like their ages, mass, and temperature.

More information:

The stars revealed by this image were discussed in the paper “The VMC Survey - XXXIV. Morphology of Stellar Populations in the Magellanic Clouds” to appear in the journal Monthly Notices of the Royal Astronomical Society.

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”.

Links:

ESOcast 206 Light: VISTA Unveils the Large Magellanic Cloud
https://www.eso.org/public/videos/eso1914a/

Research paper: https://www.eso.org/public/archives/releases/sciencepapers/eso1914/eso1914a.pdf

Photos of VISTA: http://www.eso.org/public/images/archive/category/surveytelescopes/

ESO’s VISTA telescope: https://www.eso.org/public/teles-instr/paranal-observatory/surveytelescopes/vista/

Images, Text, Credits: ESO/Mariya Lyubenova/Leibniz-Institut für Astrophysik Potsdam (AIP)/Maria-Rosa Cioni/ESO/VMC Survey/IAU and Sky & Telescope/Videos: ESO, N. Rinsinger (skysurvey.org). Music: Astral Electronic/VMC Survey.

Best regards, Orbiter.ch

jeudi 12 septembre 2019

CASC - Long March-4B launches ZY-1 02D satellite













CASC - China Aerospace Science and Technology Corporation logo.

12 sept. 2019

Long March-4B launches ZY-1 02D satellite

A Long March-4B launch vehicle launched ZY-1 02D Earth-observation satellite and two small satellites from the Taiyuan Satellite Launch Center, Shanxi Province, northern China, on 12 September 2019, at 03:26 UTC (11:26 local time).

Long March-4B launches ZY-1 02D satellite

According to official sources, ZY-1 02D will provide observation data for natural resources asset management, ecological monitoring, disaster prevention and control, environmental protection, urban construction, transportation and contingency management.

ZY-1 02D satellite

The small satellite BNU-1 was developed by Beijing Normal University and the other satellite belongs to a Shanghai-based private space technology company. Both have an expected lifespan of one year.

It will provide observation data for natural resources asset management, ecological monitoring, disaster prevention and control, environmental protection, urban construction, transportation and contingency management. With an expected lifespan of five years, ZY-1 02D will form a network with more satellites to follow.

China Aerospace Science and Technology Corporation (CASC): http://english.spacechina.com/n16421/index.html

Images, Text, Video, Text, Credits: CASC/CNSA/China Central Television (CCTV)/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

New Station Crew Continues Preparations for Launch as Expedition 60 Enjoys Off Day













ISS - Expedition 60 Mission patch.

September 12, 2019

The crew of Expedition 60, consisting of Commander Alexey Ovchinin of Roscosmos; NASA astronauts Christina Koch, Andrew Morgan and Nick Hague; ESA (European Space Agency) astronaut Luca Parmitano; and cosmonaut Alexander Skvortsov, took much-needed respite during an off-duty day aboard the International Space Station. Tomorrow, investigations furthering scientific research in support of crew health and extended travels to destinations deeper in the solar system will resume.


Image above: In the Integration Building at the Baikonur Cosmodrome in Kazakhstan, Expedition 61 crew member Jessica Meir of NASA runs through procedures Sept. 11 aboard the Soyuz MS-15 spacecraft during an initial Soyuz vehicle fit check. Image Credits: NASA/Victor Zelentsov.

On Earth, the Expedition 61 prime crew of cosmonaut Oleg Skripochka and NASA astronaut Jessica Meir, along with spaceflight participant Hazzaa Ali Almansoori, are at the Gagarin Cosmonaut Training Center in Star City, Russia, finalizing pre-launch training and preparations for their launch on Sept. 25 aboard a Soyuz MS-15 spacecraft. Yesterday, they ran through procedures and completed the necessary fit check, spacesuits donned, within the Soyuz vehicle. Today, they took part in ceremonial activities, such as raising the flags of Russia, the United States, and the United Arab Emirates, along with backup crew members Tom Marshburn of NASA, Sergey Ryzhikov of Roscosmos and spaceflight participant Sultan Al-Neyadi of the United Arab Emirates.

International Space Station (ISS). Animation Credit: NASA

Related links:

Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/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), Animation (mentioned), Text, Credits: NASA/Catherine Williams.

Best regards, Orbiter.ch

Two Asteroids to Safely Fly by Earth












Asteroid Watch logo.

Sept. 12, 2019

Two relatively medium-sized asteroids will fly safely past Earth overnight Sept. 13-14 (Eastern U.S. time). NASA is tracking the objects, but orbit calculations ruled out any chance that the objects could pose a threat to our planet.

“These asteroids have been well observed—once since 2000 and the other since 2010—and their orbits are very well known,” said Lindley Johnson, planetary defense officer and program executive for the Planetary Defense Coordination Office at NASA Headquarters in Washington, DC. “Both of these asteroids are passing at about 14 lunar distances from the Earth, or about 3.5 million miles away, but small asteroids pass by Earth this close all the time.”


Near-Earth asteroid 2010 C01, estimated to be 400 to 850 feet (120 to 260 meters) in size, will safely pass Earth at 11:42 p.m. EDT on Sept. 13 (3:42 UTC on Sept. 14). The second object, 2000 QWZ is estimated to be 950 to 2,100 feet (290 to 650 meters) in size will pass later at 7:54 a.m. EDT Sept. 14 (23:54 UTC).

What is a near-Earth object?

Near-Earth objects (NEOs) are asteroids and comets that orbit the Sun, but their orbits bring them into Earth’s neighborhood – within 30 million miles of Earth’s orbit.

Near-Earth Asteroid's

These objects are relatively unchanged remnant debris from the solar system’s formation some 4.6 billion years ago. Most of the rocky asteroids originally formed in the warmer inner solar system between the orbits of Mars and Jupiter, while comets, composed mostly of water ice with embedded dust particles, formed in the cold outer solar system.

Who searches for near-Earth objects?

NASA’s Near-Earth Object (NEO) Observations Program finds, tracks and monitors near-Earth asteroids and comets. Astronomers supported by the program use telescopes to follow up the discoveries to make additional measurements, as do many observatories all over the world. The Center for Near-Earth Object Studies, based at NASA’s Jet Propulsion Laboratory, also uses these data to calculate high-precision orbits for all known near-Earth objects and predict future close approaches by them to Earth, as well as the potential for any future impacts.

How Does NASA Spot a Near-Earth Asteroid?

How do we calculate the orbit of a near-Earth object?

Scientists determine the orbit of an asteroid by comparing measurements of its position as it moves across the sky to the predictions of a computer model of its orbit around the Sun. The more observations that are used and the longer the period over which those observations are made, the more accurate the calculated orbit and the predictions that can be made from it.

How many near-Earth objects have been discovered so far?
 
All Known Asteroids in the Solar System (1999-2018)

At the start of 2019, the number of discovered NEOs totaled more than 19,000, and it has since surpassed 20,000. An average of 30 new discoveries are added each week. More than 95 percent of these objects were discovered by NASA-funded surveys since 1998, when NASA initially established its NEO Observations Program and began tracking and cataloguing them.

Related links:

Planetary Defense Coordination Office: https://www.nasa.gov/planetarydefense/overview

Near-Earth Object (NEO) Observations Program: https://www.nasa.gov/planetarydefense/neoo

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

Read More:

NASA Planetary Defense: https://www.nasa.gov/planetarydefense

NASA Center for Near-Earth Object Studies: https://cneos.jpl.nasa.gov/

International Astronomical Union (IAU) Minor Planet Center: https://www.minorplanetcenter.net/iau/mpc.html

Twitter: Asteroid Watch: https://twitter.com/AsteroidWatch

Asteroids: https://www.nasa.gov/mission_pages/asteroids/main/index.html

Images, Videos, Text, Credits: NASA/Brian Dunbar/ESA.

Greetings, Orbiter.ch

Hubble Reveals Latest Portrait of Saturn













ESA - Hubble Space Telescope logo.

12 September 2019

Latest Saturn Portrait

The NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on 20 June 2019 as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometres away.

Since the Hubble Space Telescope was launched, its goal has been to study not only distant astronomical objects, but also the planets within our Solar System. Hubble’s high-resolution images of our planetary neighbours can only be surpassed by pictures taken from spacecraft that actually visit these bodies. However, Hubble has one advantage over space probes; it can look at these objects periodically and observe them over much longer periods than any passing probe could.

The Moons of Saturn (annotated)

Saturn hosts many recognisable features, most notably its trademark ring system, which is now tilted towards Earth. This gives us a magnificent view of its bright icy structure. Hubble resolves numerous ringlets and the fainter inner rings. Dutch astronomer Christiaan Huygens first identified the rings in 1655 and thought they were a continuous disk encircling the planet, but we now know them to be composed of orbiting particles of ice and dust. Though all of the gas giants boast rings, Saturn’s are the largest and most spectacular.

The age of Saturn’s ring system continues to be debated. And, even more perplexingly, it’s unknown what cosmic event formed the rings. There is no consensus among planetary astronomers today.

Another intriguing feature is the long-lasting hexagon-shaped structure circling the planet’s north pole. It is a mysterious six-sided pattern caused by a high-speed jetstream. The hexagon is so large that four Earths could fit inside its boundaries (there is no similar structure at Saturn’s south pole).

Pan Over Saturn

Other features, however, are not as long-lasting. A large storm in the north polar region spotted by Hubble last year has disappeared. Smaller, convective storms, such as the one just above the centre of the planet’s image, also come and go.

Saturn’s amber colours come from summer smog-like hazes, produced in photochemical reactions driven by solar ultraviolet radiation. Below the haze lie clouds of ammonia ice crystals, as well as deeper, unseen lower-level clouds of ammonium hydrosulphide and water. The planet’s banded structure is caused by the winds and clouds at different altitudes.

Animation of Saturn’s Moon

Saturn’s appearance changes with its seasons, caused by the planet’s 27-degree axial tilt. This image was taken during summer in the planet’s northern hemisphere.

This image is the second in a yearly series of snapshots taken as part of the Outer Planets Atmospheres Legacy (OPAL) project. OPAL is helping scientists to understand the atmospheric dynamics and evolution of our Solar System’s gas giant planets. In Saturn’s case, astronomers will be able to track shifting weather patterns and other changes to identify trends.

Hubble Space Telescope (HST)

More information:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

Links:

Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

Images of Saturn from Hubble: https://www.spacetelescope.org/images/archive/search/?ranking=0&fov=0&release_id=&minimum_size=0&description=&published_until_year=0&published_until_month=0&title=&subject_name=Saturn&credit=&published_until_day=0&published_since_day=0&published_since_month=0&type=Observation&id=&published_since_year=0

Hubblesite release: https://hubblesite.org/contents/news-releases/2019/news-2019-43

Outer Planets Atmospheres Legacy (OPAL): https://archive.stsci.edu/prepds/opal/

Images, Videos, Animation, Text, Credits: NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley)/NASA, ESA, A. Simon (GSFC) and the OPAL Team/Videos: NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley)/NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley), and J. DePasquale (STScI).

Best regards, Orbiter.ch

Interstellar 2.0













ESA - European Space Agency patch.

12 September 2019

Astronomers have spotted an object that looks likely to be a very rare visitor from outside our Solar System. If confirmed, this unusual body would be only the second interstellar object ever detected passing through our neighbourhood.

Artist impression of ‘Oumuamua

Like the fascinating cigar-shaped ʻOumuamua, which flew by in 2017, this bright object is also a comet, yet it cuts a very different shape in the sky.

The new object, dubbed C/2019 Q4, was first detected on 30 August by Gennady Borisov from the Crimean Astrophysical Observatory.

About a week later, Marco Micheli from ESA’s Near-Earth Object Coordination Centre obtained images through the International Scientific Optical Network and performed several position measurements using data taken with the Canada-France-Hawaii Telescope in Hawaii.

This data confirmed the object’s unusual orbit, which was first reported by NASA’s Scout system, a real time monitor of newly discovered asteroids and comets.

ESA is now analysing all available data, as well as planning more observations to further refine the object’s path through space.

Canada France Hawaii Telescope

Despite being monitored by many telescopes and astronomers around the globe, there is still some uncertainty in the path and the origin of this interesting object.

Like the unfolding story of ‘Oumuamua – first thought to be an asteroid then finally a comet – this looks set to be another exciting scientific investigation of an unusual visitor, helping boost our knowledge of solar system formation.

Between the stars

As the word suggests, an interstellar object is ‘between the stars’, roaming through space and no longer bound or ‘trapped’ in orbit about any specific star around which they formed.

Astronomers can tell a lot about an object from the shape of its orbit, in particular its eccentricity – how much it is ‘stretched’.

Hyperbolic orbit of comet C/2019 Q4

Planets in near-perfect circular orbits around their star, Earth for example, have an eccentricity close to zero.

Comets and asteroids in orbit around a body with elongated paths are described as having an eccentricity of between zero and one, and objects with an eccentricity greater than one, ‘hyperbolic’ orbits, are interstellar.

Current observations strongly suggest that C/2019 Q4 is interstellar, its orbit being highly elongated with an eccentricity of about three.

However, we also know that the uncertainty in these early observations is high as they were taken as the object was near the Sun in the sky and close to the horizon – two factors that negatively affect the quality of observations.

ESA's detection expertise

Vitally, it also requires measurements taken over an extended period to really determine an object’s path, to understand where it has come from and where it is headed.

When a comet or asteroid is first detected, it is merely a tiny point of light. But over time, multiple observations allow astronomers to ‘draw an arc in the sky’, from which the object’s orbit can be extrapolated.

“We are now working on getting more observations of this unusual object,” says Marco Micheli of ESA’s Near-Earth Object Coordination Centre.

“We need to wait a few days to really pin down its origin with observations that will either prove the current thesis that it is interstellar, or perhaps drastically change our understanding”.

Dirty snowballs

We do know so far, that C/2019 Q4 is a relatively large active comet a few kilometres in diameter. It is expected to make its closest approach to the Sun in early December, coming within about 300 million km of our star.

At this distance it is not considered a near-Earth object (NEO) – a comet or asteroid travelling in a path that would see it come close to Earth – of which there are currently more than 20 000 known to date.

Image of Comet C/2002 V1 (NEAT)

Comets are cold, fragile and irregular bodies made up of frozen gasses and grains of dust. Usually, they travel in highly elongated – or stretched – orbits around the Sun, spending most of their time far away at freezing temperatures but passing briefly by our raging star – and not always surviving the encounter.

If they pass close enough, the Sun’s radiation causes a comet’s volatile gases to ‘sublimate’ – going from solid ice to vapour gas in one step, taking with them small bits of solid material and creating enormous ‘tails’ that trail behind the icy body.

Comet Interceptor

Had comet C/2019 Q4 entered our Solar System a few years later, it could have been a potential candidate for ESA’s ‘Comet Interceptor’ mission.

Comprising three spacecraft, Comet Interceptor's primary target will be to visit a truly pristine comet in the Oort cloud but could include an interstellar object as it begins its journey into the inner Solar System.

Comet activity – 22 November 2014

If confirmed as interstellar, as was ‘Oumuamua, the discovery of two such bodies in just two years may suggest that these objects are far more common than previously suspected.

This is an exciting prospect for the interceptor mission and adds to our understanding of the formation of our Solar System and others throughout the Universe.

Planetary defence

New near-Earth objects are constantly being discovered, some of which are added to ESA’s ‘risk list’ and all of which are monitored by ESA’s NEO Coordination Centre, part of the Planetary Defence Office.

Find out more about the work of the Office, including the planned Hera mission to test asteroid deflection, here: http://www.esa.int/Our_Activities/Space_Safety/Risky_asteroids

Related links:

Comet Interceptor: http://www.esa.int/Our_Activities/Space_Science/ESA_s_new_mission_to_intercept_a_comet

Risk list: http://neo.ssa.esa.int/risk-page

Crimean Astrophysical Observatory: http://crao.ru/ru/

Near-Earth Object Coordination Centre: http://neo.ssa.esa.int/

International Scientific Optical Network: http://lfvn.astronomer.ru/main/english.htm

NASA’s Scout system: https://cneos.jpl.nasa.gov/scout/

Space Safety: http://www.esa.int/Our_Activities/Space_Safety

Images, Video, Text, Credits: ESA/Hubble, NASA, ESO, M. Kornmesser/Canada France Hawaii Telescope/B. Dintinjana and J. Skvarc/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA.

Greetings, Orbiter.ch

Unexpected periodic flares may shed light on black hole accretion













ESA - XMM-Newton Mission patch.

12 September 2019

ESA’s X-ray space telescope XMM-Newton has detected never-before-seen periodic flares of X-ray radiation coming from a distant galaxy that could help explain some enigmatic behaviours of active black holes.

XMM-Newton observations

XMM-Newton, the most powerful X-ray observatory, discovered some mysterious flashes from the active black hole at the core of the galaxy GSN 069, about 250 million light years away. On 24 December 2018, the source was seen to suddenly increase its brightness by up to a factor 100, then dimmed back to its normal levels within one hour and lit up again nine hours later.

“It was completely unexpected,” says Giovanni Miniutti, of the Centro de Astrobiología in Madrid, Spain, lead author of a new paper published in the journal Nature today. 

“Giant black holes regularly flicker like a candle but the rapid, repeating changes seen in GSN 069 from December onwards are something completely new.”

Further observations, performed with XMM-Newton as well as NASA’s Chandra X-ray observatory in the following couple of months, confirmed that the distant black hole was still keeping the tempo, emitting nearly periodic bursts of X-rays every nine hours. The researchers are calling the new phenomenon ‘quasi-periodic eruptions’, or QPEs.

“The X-ray emission comes from material that is being accreted into the black hole and heats up in the process,” explains Giovanni.

“There are various mechanisms in the accretion disc that could give rise to this type of quasi-periodic signal, potentially linked to instabilities in the accretion flow close to the central black hole.

Optical and X-ray view

“Alternatively, the eruptions could be due to the interaction of the disc material with a second body – another black hole or perhaps the remnant of a star previously disrupted by the black hole.”

Although never before observed, Giovanni and colleagues think periodic flares like these might actually be quite common in the Universe.

It is possible that the phenomenon had not been identified before because most black holes at the cores of distant galaxies, with masses millions to billions of times the mass of our Sun, are much larger than the one in GSN 069, which is only about 400 000 times more massive than our Sun.

The bigger and more massive the black hole, the slower the fluctuations in brightness it can display, so a typical supermassive black hole would erupt not every nine hours, but every few months or years. This would make detection unlikely as observations rarely span such long periods of time.

And there is more. Quasi-periodic eruptions like those found in GSN 069 could provide a natural framework to interpret some puzzling patterns observed in a significant fraction of active black holes, whose brightness seems to vary too fast to be easily explained by current theoretical models.

“We know of many massive black holes whose brightness rises or decays by very large factors within days or months, while we would expect them to vary at a much slower pace,” says Giovanni.

“But if some of this variability corresponds to the rise or decay phases of eruptions similar to those discovered in GSN 069, then the fast variability of these systems, which appears currently unfeasible, could naturally be accounted for. New data and further studies will tell if this analogy really holds.”

Quasi-periodic eruptions in GSN 069

The quasi-periodic eruptions spotted in GSN 069 could also explain another intriguing property observed in the X-ray emission from nearly all bright, accreting supermassive black holes: the so-called ‘soft excess’.

It consists in enhanced emission at low X-ray energies, and there is still no consensus on what causes it, with one leading theory invoking a cloud of electrons heated up near the accretion disc.

Like similar black holes, GSN 069 exhibits such a soft X-ray excess during bursts, but not between eruptions.

“We may be witnessing the formation of the soft excess in real time, which could shed light on its physical origin,” says co-author Richard Saxton from the XMM-Newton operation team at ESA’s astronomy centre in Spain.

“How the cloud of electrons is created is currently unclear, but we are trying to identify the mechanism by studying the changes in the X-ray spectrum of GSN 069 during the eruptions.”


Image above: Bubbles of radio waves spotted at the centre of the Milky Way.Image Credit: South African Radio Astronomy Observatory (SARAO).

The team is already trying to pinpoint the defining properties of GSN 069 at the time when the periodic eruptions were first detected to look for more cases to study.

"One of our immediate goals is to search for X-ray quasi-periodic eruptions in other galaxies, to further understand the physical origin of this new phenomenon,” adds co-author Margherita Giustini of Madrid’s Centro de Astrobiología. 

“GSN 069 is an extremely fascinating source, with the potential to become a reference in the field of black hole accretion,” says Norbert Schartel, ESA’s XMM-Newton project scientist.

XMM-Newton

The discovery would not have been possible without XMM-Newton’s capabilities.

“These bursts happen in the low energy part of the X-ray band, where XMM-Newton is unbeatable. We will certainly need to use the observatory again if we want to find more of these kinds of events in the future,” concludes Norbert.

Notes for editors:

‘Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus’ by G. Miniutti et al. is published in Nature: https://www.nature.com/articles/s41586-019-1556-x

The international research team used astronomical data from ESA’s XMM-Newton, NASA’s Chandra and Swift X-ray observatories, the NASA/ESA Hubble Space Telescope, NRAO’s Karl G. Jansky Very Large Array in New Mexico, USA, CSIRO’s Australia Telescope Compact Array in Australia, and SARAO’s MeerKAT radio telescope in South Africa.

More on this discovery on Nature’s blog: https://astronomycommunity.nature.com/users/300795-giovanni-miniutti/posts/53402-newly-discovered-x-ray-quasi-periodic-eruptions-qpes-from-a-galactic-nucleus-may-shed-light-on-bh-accretion

And Nature website: Giant ‘bubbles’ spotted around Milky Way’s black hole
https://www.nature.com/articles/d41586-019-02726-x?utm_source=Nature+Briefing&utm_campaign=6fb58d2862-briefing-dy-20190912&utm_medium=email&utm_term=0_c9dfd39373-6fb58d2862-44141929

XMM-Newton: https://sci.esa.int/web/xmm-newton/

Animations, Images, Text, Credits: ESA/Norbert Schartel/Centro de Astrobiología (CAB, CSIC-INTA)/Margherita Giustini/Giovanni Miniutti/Telespazio-Vega UK for ESA/Richard Saxton/ESA/XMM-Newton; NASA/CXC; G. Miniutti (CAB, CSIC-INTA, Spain).

Greetings, Orbiter.ch

mercredi 11 septembre 2019

Decoding Human Biology at Top of Task List for Station Residents













ISS - Expedition 60 Mission patch.

September 11, 2019

Expedition 60 is in the midst of a busy week aboard the International Space Station, even with yesterday’s launch scrub of the Japan Aerospace Exploration Agency (JAXA) HTV-8 “Kounotori” cargo vehicle. While JAXA teams are meeting to discuss a forward plan and assess launch opportunities, mission operations and scientific investigations are moving forward in orbit.  

Half the crew —NASA astronauts Christina Koch and Andrew Morgan ESA (European Space Agency) crewmate Luca Parmitano— spent part of their day reviewing spacewalk procedures and training for an upcoming series of spacewalks to upgrade batteries during a maintenance activity for the outpost.


Image above: Expedition 60 Flight Engineer Christina Koch of NASA playfully demonstrates how fluids behave in the weightless environment of microgravity aboard the International Space Station. Image Credit: NASA.

Morgan also assisted NASA astronaut Nick Hague and cosmonaut Alexander Skvortsov of Roscosmos with additional work in support of Fluid Shifts, again evaluating a Chibis Lower Body Negative Pressure suit as a potential countermeasure for explorers having trouble maintaining adequate blood pressure during phases of egress and landing.

Koch, meanwhile, performed necessary maintenance for the Rodent Research-17 experiment, temporarily relocating the rodent occupants to clean out the habitats and restock them with new food bars. This investigation evaluates the physiological, cellular and molecular effects of microgravity, testing the theory that the cosmic environment can accelerate aging. As researchers gain a better understanding of immune, bone and muscle disease processes, new therapies in space and on Earth can beneficially result.

International Space Station (ISS). Animation Credit: NASA

Parmitano rounded out the busy day by performing a self-guided ultrasound for the ground team in support of the Vascular Echo study, which examines changes in blood vessels and the heart in astronauts. It’s been observed that Expedition crew members return to Earth with stiffer arteries than they had before going into space. This experiment will provide insight into potential countermeasures to maintain crew health and improve quality of life for everyone … including those of us on Earth.

Related articles:

HTV-8 Launch Scrubbed for Tonight
https://orbiterchspacenews.blogspot.com/2019/09/htv-8-launch-scrubbed-for-tonight.html

JAXA - H-IIB F8/HTV-8 launch-pad in fire
https://orbiterchspacenews.blogspot.com/2019/09/jaxa-h-iib-f8htv-8-launch-pad-in-fire.html

Related links:

Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html

Fluid Shifts: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1126

Rodent Research-17: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7992

Vascular Echo: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1664

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/Catherine Williams.

Best regards, Orbiter.ch

Hubble Finds Water Vapor on Habitable-Zone Exoplanet for 1st Time












NASA - Hubble Space Telescope patch.

Sept. 11, 2019

Its size and surface gravity are much larger than Earth’s, and its radiation environment may be hostile, but a distant planet called K2-18b has captured the interest of scientists all over the world. For the first time, researchers have detected water vapor signatures in the atmosphere of a planet beyond our solar system that resides in the "habitable zone," the region around a star in which liquid water could potentially pool on the surface of a rocky planet.

Astronomers at the Center for Space Exochemistry Data at the University College London in the United Kingdom used data from NASA’s Hubble Space Telescope to find water vapor in the atmosphere of K2-18b, an exoplanet around a small red dwarf star about 110 light-years away in the constellation Leo. If confirmed by further studies, this will be the only exoplanet known to have both water in its atmosphere and temperatures that could sustain liquid water on a rocky surface. Liquid water would only be possible if the planet turns out to be terrestrial in nature, rather than resembling a small version of Neptune.


Image above: This artist’s impression shows the planet K2-18b, its host star and an accompanying planet in this system. K2-18b is now the only super-Earth exoplanet known to host both water and temperatures that could support life. UCL researchers used archive data from 2016 and 2017 captured by the NASA/ESA Hubble Space Telescope and developed open-source algorithms to analyze the starlight filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapor, also indicating the presence of hydrogen and helium in the planet’s atmosphere. Image Credits: ESA/Hubble, M. Kornmesser.

Given the high level of activity of its red dwarf star, K2-18b may be more hostile to life as we know it than Earth, as it is likely to be exposed to more high-energy radiation. The planet, discovered by NASA's Kepler Space Telescope in 2015, also has a mass eight times greater than Earth's. That means the surface gravity on this planet would be significantly higher than on our planet.

The team used archive data from 2016 and 2017 captured by Hubble and developed open-source algorithms to analyze the host star’s light filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapor, and also suggest the presence of hydrogen and helium in the planet’s atmosphere.

Hubble Finds Water Vapor On Distant Exoplanet

Video above: With data from the Hubble Space Telescope, water vapor has been detected in the atmosphere of an exoplanet within the habitable zone of its host star. K2-18b, which is eight times the mass of Earth, is the only planet orbiting a star outside the solar system (or “exoplanet”) known to have both water and temperatures that could support life. Video Credits: NASA's Goddard Space Flight Center.

The authors of the paper, published in Nature Astronomy, believe that other molecules, including nitrogen and methane, may be present but they remain undetectable with current observations. Further studies are required to estimate cloud coverage and the percentage of atmospheric water present. A paper from a different team of scientists using Hubble observations has been submitted to the Astronomical Journal.

K2-18b is one of hundreds of "super-Earths" — exoplanets with masses between those of Earth and Neptune — found by Kepler. NASA’s TESS mission is expected to detect hundreds more super-Earths in the coming years. The next generation of space telescopes, including the James Webb Space Telescope, will be able to characterize exoplanet atmospheres in more detail.

Hubble Space Telescope (HST)

The Hubble Space Telescope is a project of international cooperation between ESA (the European Space Agency) and NASA.

Related links:

Exoplanet: https://exoplanets.nasa.gov/

Hubble Space Telescope (HST): https://www.nasa.gov/mission_pages/hubble/main/index.html

Image, Animation, Video, Text, Credits: NASA/ESA/Rob Garner/GSFC/Claire Andreoli.

Greetings, Orbiter.ch

Scientists Discover Black Hole Has Three Hot Meals a Day













NASA - Chandra X-ray Observatory patch.

Sept. 11, 2019


There’s an adage that it’s not healthy to skip meals. Apparently, a supermassive black hole in the center of a galaxy millions of light years away has gotten the message.

A team of astronomers found X-ray bursts repeating about every nine hours originating from the center of a galaxy called GSN 069. Obtained with NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton, these data indicate that   the supermassive black hole located there is consuming large amounts of material on a regular schedule.

While scientists had previously found two “stellar-mass” black holes (that weigh about 10 times the Sun’s mass) occasionally undergoing regular outbursts before, this behavior has never been detected from a supermassive black hole until now.

The black hole at the center of GSN 069, located 250 million light years from Earth, contains about 400,000 times the mass of the Sun. The researchers estimate that the black hole is consuming about four Moons’ worth of material about three times a day. That’s equivalent to almost a million billion billion pounds going into the black hole per feeding.

“This black hole is on a meal plan like we’ve never seen before,” said Giovanni Miniutti from ESA’s Center for Astrobiology in Spain, the first author of a Nature paper, published today, describing these results. “This behavior is so unprecedented that we had to coin a new expression to describe it: “X-ray Quasi-Periodic Eruptions”.”

ESA's XMM-Newton was the first to observe this phenomenon in GSN 069 with the detection of two bursts on December 24, 2018. Miniutti and colleagues then followed up with more XMM-Newton observations on January 16 and 17, 2019, and found five outbursts. Observations by Chandra less than a month later, on February 14, revealed an additional three outbursts.

“By combining data from these two X-ray observatories, we have tracked these periodic outbursts for at least 54 days” said co-author Richard Saxton of the European Space Astronomy Centre in Madrid, Spain. “This gives us a unique opportunity to witness the flow of matter into a supermassive black hole repeatedly speeding up and slowing down.”


During the outbursts the X-ray emission becomes about 20 times brighter than during the quiet times. The temperature of gas falling towards the black hole also climbs, from about one million degrees Fahrenheit during the quiet periods to about 2.5 million degrees Fahrenheit during the outbursts. The temperature of the latter is similar to that of gas found around most actively growing supermassive black holes.

The origin of this hot gas has been a long-standing mystery because it appears to be too hot to be associated with the disk of infalling matter surrounding the black holes. Although its origin is also a mystery in GSN 069, the ability to study a supermassive black hole where hot gas repeatedly forms then disappears may provide important clues.

“We think the origin of the X-ray emission is a star that the black hole has partially or completely torn apart and is slowly consuming bit by bit.” said co-author Margherita Giustini, also of ESA’s Center for Astrobiology. “But as for the repeating bursts, this is a completely different story whose origin needs to be studied with further data and new theoretical models”.

The consumption of gas from a disrupted star by a supermassive black hole has been observed before, but never accompanied by repetitive X-ray bursts. The authors suggest there are two possible explanations for the bursts. One is that the amount of energy in the disk builds up until it becomes unstable and matter rapidly falls into the black hole producing the bursts. The cycle would then repeat. Another is that there is an interaction between the disk and a secondary body orbiting the black hole, perhaps the remnant of the partially disrupted star.



The Chandra data were crucial for this study because they were able to show that the X-ray source is located in the center of the host galaxy, which is where a supermassive black hole is expected to be. The combination of data from Chandra and XMM-Newton implies that the size and duration of the black hole’s meals have decreased slightly, and the gap between the meals has increased. Future observations will be crucial to see if the trend continues.

Chandra X-ray Observatory



Supermassive black holes are usually larger than GSN 069, with masses of millions or even billions of suns. The larger the black hole the slower their fluctuations in brightness will be, so instead of erupting every nine hours they should erupt every few months or years which likely explains why quasi-periodic eruptions where never seen before.

Examples of large increases or decreases in the amount of X-rays produced by black holes have been observed in a few cases, using repeated observations over months or even years. The changes in some objects are much faster than expected by standard theory of disks of infalling matter surrounding black holes, but could be naturally accounted for if they were experiencing similar behavior to GSN 069.

Along with data from Chandra and XMM-Newton the international research team used data from NASA’s Swift X-ray observatory, the NASA/ESA Hubble Space Telescope, NRAO’s Karl G. Jansky Very Large Array in New Mexico, USA, CSIRO’s Australia Telescope Compact Array in Australia, and SARAO’s MeerKAT radio telescope in South Africa.

This paper appears in the September 11, 2019 issue of the journal Nature. NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science and flight operations from Cambridge, Massachusetts.

Read more from NASA's Chandra X-ray Observatory: https://chandra.harvard.edu/photo/2019/gsn069/index.html

For more Chandra images, multimedia and related materials, visit: http://www.nasa.gov/chandra

Image, Animation, Text, Credits: X-ray: NASA/CXO/CSIC-INTA/G.Miniutti et al.; Optical: DSS/NASA/Lee Mohon.

Greetings, Orbiter.ch

HTV-8 Launch Scrubbed for Tonight













ISS - Expedition 60 Mission patch.

September 11, 2019


Image above: The Japanese HTV-6 cargo vehicle is seen during final approach to the International Space Station. Like HTV-8, HTV-6 was loaded with more than 4 tons of supplies, water, spare parts and experiment hardware. Image Credit: NASA.

Mission Control in Houston informed the crew aboard the International Space Station that tonight’s launch of the Japan Aerospace Exploration Agency (JAXA) unpiloted H-II Transfer Vehicle-8 (HTV-8) cargo spacecraft was scrubbed due to a fire on or near the launch pad at Tanegashima Space Center. The astronauts are safe aboard the station and well supplied.

International Space Station (ISS). Animation Credit: NASA

Related article:

JAXA - H-IIB F8/HTV-8 launch-pad in fire
https://orbiterchspacenews.blogspot.com/2019/09/jaxa-h-iib-f8htv-8-launch-pad-in-fire.html

Related links:

Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html

Japan Aerospace Exploration Agency (JAXA): https://global.jaxa.jp/

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/Norah Moran.

Best regards, Orbiter.ch

mardi 10 septembre 2019

JAXA - H-IIB F8/HTV-8 launch-pad in fire













JAXA - H-IIB Launch Vehicle No. 8 (H-IIB F8) Mission patch.

Sept. 10, 2019

H-IIB F8/HTV-8 launch-pad in fire

A Japanese H-2B rocket will launch the eighth H-2 Transfer Vehicle. The HTV serves as an automated cargo vehicle to deliver equipment and supplies to the International Space Station.

H-IIB F8/HTV-8 launchpad fire

JAXA’s H-IIB Launch Vehicle No. 8 (H-IIB F8) launch with the H-II Transfer Vehicle “KOUNOTORI8” (HTV-8) from the Yoshinobu Launch Complex, at JAXA’s Tanegashima Space Center, was canceled on 10 September 2019 due to a fire on the launchpad. The fire was extinguished, the causes are under investigation.

Related articles:


JAXA Spacecraft Carries Science, Technology to the Space Station
https://orbiterchspacenews.blogspot.com/2019/09/jaxa-spacecraft-carries-science.html

JAXA and Sony CSL to Conduct In-Orbit Demonstrations of Long-Distance Laser Communication
https://orbiterchspacenews.blogspot.com/2019/08/jaxa-and-sony-csl-to-conduct-in-orbit.html

Related links:

H-II Transfer Vehicle-8 (HTV-8): https://www.nasa.gov/mission_pages/station/structure/elements/htv.html

Japan Aerospace Exploration Agency (JAXA): https://global.jaxa.jp/

Image, Video, Text, Credits: JAXA/NECOVIDEO VISUAL SOLUTIONS/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Studying flames in microgravity is helping make combustion on Earth cleaner, and space safer













ISS - International Space Station logo.

Sept. 10, 2019

Understanding how fire spreads and behaves in space is crucial for the safety of future astronauts and for understanding and controlling fire here on Earth.

Microgravity is also crucial for combustion researchers to test some of the core principles of the field. “If you look at any textbook on combustion, almost all of the theories that are developed ignore the influence of gravity,” says NASA’s Glenn Research Center scientist Daniel Dietrich.


Image above: This flame was one of many ignited as part of the Flame Design investigation inside of CIR to investigate the amount of soot that is produced in different conditions. The yellow spots are soot clusters that glow yellow when hot. These clusters grow larger in microgravity than on Earth because the soot remains within the flame longer. Image Credit: NASA.

The primary focus of microgravity combustion experiments has been related to either fire safety in space or better understanding of practical combustion on Earth and in space. The reduced gravity creates flames that look a lot different from the ones seen here on Earth: with the near absence of gravity on the space station, flames tend to be spherical. On Earth, hot gasses from the flame rise while gravity pulls cooler, denser air to the bottom of the flame. This creates both the shape of the flame, as well as a flickering effect. In microgravity, this flow doesn’t occur. This reduces the variables in combustion experiments, making them simpler and creating spherical shaped flames.

Learning to make cleaner or more efficient flames can have an impact on many areas of our lives. “Most of our electricity in the U.S. is generated by combustion,” says Glenn project scientist Dennis Stocker. “In regards to power transportation, where would we be without combustion? So combustion is a big part of our modern lives.”


Image above: NASA astronaut and Expedition 59 Flight Engineer Christina Koch works inside the U.S. Destiny laboratory module's Combustion Integrated Rack. She was replacing hardware for a series of experiments collectively known as Advanced Combustion via Microgravity Experiments (ACME). Image Credit: NASA.

As with other space station research, experiments with combustion are developed to be safely conducted without risk to the spacecraft or its crew. That is why the Combustion Integrated Rack (CIR) was created and launched to the International Space Station in 2008. The CIR, along with facilities such as the Microgravity Science Glovebox, created a secure and safe environment in which to study combustion without putting the crew in danger. The CIR provides general-purpose hardware to support a wide range of combustion experiments. Researchers also have provided additional hardware needed to conduct a variety of flame experiments.

“One of the biggest discoveries, not only in the microgravity program, but in probably the past 20 – 30 years of combustion research has been during the FLEX experiments on the space station,” says Dietrich. The FLame Extinguishment Experiment (FLEX) was analyzing the effectiveness of fire suppressants by studying burning fuel droplets in the CIR, when researchers accidentally made a surprising discovery related to cool flames, or apparent continued "burning" after flame extinction under certain conditions.

“It's not only important from a nerdy theoretical combustion point of view, but also from a practical point of view,” says Dietrich. “The low temperature chemical reactions that we can study on facilities like the space station are very important in real combustion systems like engines.”

However, the CIR is not the only way to perform combustion experiments using the space station. A set of notable exceptions are the Saffire experiments that occurred aboard an uncrewed Cygnus spacecraft after they detached from the station. Since these experiments occurred away from the space station, they could study topics such as fire spread and oxygen use in larger flames in microgravity.


Image above: Astronaut Michael Fincke, Expedition 18 commander, works on the Multi-User Droplet Combustion Apparatus (MDCA) Chamber Insert Assembly (CIA) in the Harmony node of the International Space Station. Image Credit: NASA.

Currently scientists are conducting a set of experiments known as the Advanced Combustion via Microgravity Experiments (ACME) on the orbiting laboratory. These tests are grouped together because they use the same modular set of hardware on the station. Together they will yield data that could help improve fuel efficiency and reduce pollutant production in practical combustion on Earth.

One of these ACME investigations, known as Flame Design, focuses on soot, the carbon residue left behind when organic matter (or other carbon-containing material) does not fully burn. Soot causes environmental and health issues, but also can be helpful in various ways; for example, by enhancing radiant heat. Radiant heat is the reason you feel warmer standing in direct sunlight than when you stand in the shade.

Normally, most flames on Earth burn in air. Inert gas is introduced at the same time as oxygen for combustion on Earth. This investigation instead introduces the inert gas with the fuel, rather than with the oxygen. “It turns out, it has a big impact on the flame,” says principal investigator Richard Axelbaum. “In this case, even though the temperatures of the flames may be the same whether you introduce the inert with the oxidizer or the fuel, the impact for soot formation or flame strength is substantially different.”

The Flame Design investigation is studying the quantity of soot produced under different flame conditions. Each test produces a flame and may produce soot clusters that glow yellow when hot. These clusters grow larger in microgravity than on Earth because the soot remains within the flame longer.

Designing Flames Aboard the International Space Station

This experiment’s results could enable the design of flames that are more sooty or soot-free, depending on the need of a specific application. “When you're completely finished with the combustion process, in general you want to have complete burnout of all the soot. That’s true when you're producing power,” says Axelbaum. “There are some other cases where your goal is to produce carbon black which is a form of soot.” For the most part though, these results may help create more efficient and less polluting burner designs.

The knowledge gained from these combustion experiments aboard the orbiting laboratory is helping us better understand fire here on Earth, but it will be crucial when preparing for future missions beyond low Earth orbit. “Part of the future is looking at partial gravity,” says Stocker. “Understanding that will be important for fire safety on other worlds, like the Moon or Mars.”

Related links:

FLame Extinguishment Experiment (FLEX): http://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=655

Saffire experiments: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1543

Advanced Combustion via Microgravity Experiments (ACME): http://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1651

Flame Design: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2059

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), Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Science Office/Erin Winick.

Greetings, Orbiter.ch