samedi 2 septembre 2017

Touchdown! Expedition 52 Back on Earth












ROSCOSMOS - Soyuz MS-04 Mission patch.

September 2, 2017


Image above: The Soyuz MS-04 vehicle is pictured the moment it touches down with the Expedition 52 crew inside. Photo Credits: NASA/Bill Ingalls.

NASA astronaut Peggy Whitson, who set multiple U.S. space records during her mission aboard the International Space Station, along with crewmates Jack Fischer of NASA and Commander Fyodor Yurchikhin of Roscosmos, safely landed on Earth Saturday at 9:21 p.m. EDT (7:21 a.m. Kazakhstan time, Sept. 3), southeast of the remote town of Dzhezkazgan in Kazakhstan.

While living and working aboard the world’s only orbiting laboratory, Whitson and Fischer contributed to hundreds of experiments in biology, biotechnology, physical science and Earth science, welcomed several cargo spacecraft delivering tons of supplies and research experiments, and conducted a combined six spacewalks to perform maintenance and upgrades to the station.

 Expedition 52 Crew Lands Safely in Kazakhstan

Among their scientific exploits, Whitson and Fischer supported research into the physical changes to astronaut’s eyes caused by prolonged exposure to a microgravity environment. They also conducted a new lung tissue study that explored how stem cells work in the unique microgravity environment of the space station, which may pave the way for future stem cell research in space.

Additional research included an antibody investigation that could increase the effectiveness of chemotherapy drugs for cancer treatment, and the study of plant physiology and growth in space using an advanced plant habitat. NASA also attached the Cosmic Ray Energetics and Mass Investigation (ISS CREAM) on the outside of the space station in August, which is now observing cosmic rays coming from across the galaxy.


Image above: This map of Kazakhstan and the surrounding areas shows the target area for landing Soyuz vehicles. Image Credit: NASA.

The crew members received a total of seven cargo deliveries during their mission. A Japanese H-II Transfer Vehicle launched to the space station in December 2016 delivering new lithium-ion batteries that were installed using a combination of robotics and spacewalks. Orbital ATK’s Cygnus spacecraft arrived at the station in April on the company’s seventh commercial resupply mission. Three SpaceX Dragon spacecraft completed commercial resupply missions to the station in February, June and August. And, Russian ISS Progress cargo spacecraft docked to the station in February and June.

Whitson’s return marks the completion of a 288-day mission that began last November and spanned 122.2 million miles and 4,623 orbits of the Earth – her third long-duration mission on the station. During her latest mission, Whitson performed four spacewalks, bringing her career total to 10. With a total of 665 days in space, Whitson holds the U.S. record and places eighth on the all-time space endurance list.

Crew of the Ship Soyuz MS-04 Back to Earth. Image Credit: ROSCOSMOS

Fischer, who launched in April, completed 136 days in space, during which he conducted the first and second spacewalks of his career. Yurchikhin, who launched with Fischer, now has a total of 673 days in space, putting him seventh place on the all-time endurance list.

Expedition 53 continues operating the station, with Randy Bresnik of NASA in command, and Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of ESA (European Space Agency) serving as flight engineers. The three-person crew will operate the station until the arrival of NASA astronauts Mark Vande Hei and Joe Acaba, and Alexander Misurkin of Roscosmos. Vande Hei, Acaba and Misurkin are scheduled to launch Sept. 12 from Baikonur, Kazakhstan.

Related links:

Expedition 52: https://www.nasa.gov/mission_pages/station/expeditions/expedition52/index.html

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

lung tissue study: https://www.nasa.gov/mission_pages/station/research/experiments/2399.html

Astronaut’s eyes: https://www.nasa.gov/mission_pages/station/research/experiments/1257.html

Antibody investigation: https://www.nasa.gov/mission_pages/station/research/experiments/2347.html

Advanced plant habitat: https://www.nasa.gov/feature/new-plant-habitat-will-increase-harvest-on-international-space-station

ISS CREAM: https://www.nasa.gov/mission_pages/station/research/experiments/1114.html

Orbital ATK: https://www.nasa.gov/mission_pages/station/structure/launch/orbital.html

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

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

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

Best regards, Orbiter.ch

Expedition 52 Trio Undocks from Station












ROSCOSMOS - Soyuz MS-04 Mission patch.

September 2, 2017

Job Well Done aboard the Space Station

Video above: Expedition 52 Commander Fyodor Yurchikhin of Roscosmos and Flight Engineers Peggy Whitson and Jack Fischer of NASA, bid farewell to the crew remaining on the orbital outpost, including NASA’s Randy Bresnik. Video Credit: NASA TV.

NASA astronauts Peggy Whitson and Jack Fischer of NASA, along with Expedition 52 Commander Fyodor Yurchikhin of the Russian space agency Roscosmos, undocked from the International Space Station at 5:58 p.m. EDT to begin their voyage home. Whitson spent 288 days in space on this mission, and Fischer and Yurchikhin each completed 136 days in space.


Image above: The Expedition 52 trio undocked on time from the International Space Station inside their Soyuz MS-04 spacecraft. Image Credit: NASA TV.

The deborbit burn is targeted for 8:29 p.m., and will lead to a landing at 9:22 p.m. NASA Television coverage of deorbit and landing begins at 8 p.m.

Watch live coverage online at: http://www.nasa.gov/live

Keep up with the International Space Station, and its research and crew members, at:

http://www.nasa.gov/station

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

Greetings, Orbiter.ch

European XFEL: World’s most powerful X-ray source starts up












European XFEL logo.

Sept. 2, 2017


Image above: The main linac driving the European XFEL, suspended from the ceiling to leave space at floor level, photographed in January 2017. (Image: D Nölle/DESY).

Yesterday, an official ceremony marked the inauguration of the European X-ray Free-Electron Laser (European XFEL, in Schenefeld-Hamburg, Germany. Extending over a distance of 3.4 km in tunnels departing from DESY in Bahrenfeld-Hamburg, it will generate ultrashort X-ray flashes at a rate of 27 000 per second with an intensity one billion times higher than the best conventional X-ray sources. The facility will produce ultrafast snapshots of atomic and molecular movements in unprecedented detail, opening completely new research opportunities for science and industry users to image electronic, chemical and biological processes.

The story of the European XFEL is a wonderful example of the longstanding R&D synergies between the high-energy physics and light-source worlds. While traditional large X-ray facilities are based on storage rings in which energetic electrons circulate while emitting X-rays, X-ray free-electron lasers (XFELs) use special accelerating structures initially conceived for a linear collider for particle physics more than 20 years ago.

Driving the European XFEL is the longest superconducting linear accelerator ever built, a 1.4-km-long machine that uses superconducting radio-frequency (SRF) cavities to accelerate electrons highly efficiently to an energy of 17.5 GeV. Despite the clear benefits of SRF cavities, before the mid-1990s the technology was not mature enough and too expensive to be practical for a large facility. Based on initial experience with individual cavities – including those of LEP – the TESLA collaboration, hosted at DESY, developed highly performing cavities and reduced the cost for a linear collider proposal and for the construction of the European XFEL. Today the European XFEL also serves as a prototype for a potential linear collider, the ILC.

Exiting the European XFEL linac, electrons are rapidly deflected in an undulating left–right pattern by traversing a long periodic array of magnets called an undulator, causing the electrons to emit intense and coherent beams of X-ray photons. X-rays emerging from the undulator finally arrive at the European XFEL headquarters in Schenefeld where user experiments will take place.


Image above: The European XFEL facility in Hamburg (on the right) and Schenefeld (Schleswig-Holstein) (Image: European XFEL).

The European XFEL is the culmination of a worldwide effort, with European XFEL GmbH being responsible for the construction and operation of the facility, especially the X-ray photon transport and experimental stations, and its largest shareholder DESY leading the construction and operation of the electron linac. The facility joins other major XFELs in the US (LCLS) and Japan (SACLA), and is expected to keep Europe at the forefront of X-ray science for at least the next 20 to 30 years.

Construction of the €1.2 billion European XFEL began in January 2009, funded by 11 countries, with Germany and Russia as the largest contributors, although no fewer than 17 European institutes contributed in-kind to the accelerator complex. “The European XFEL is the result of intense technological development in a worldwide collaboration that has exceeded expectations,” says Eckhard Elsen, CERN’s Director for Research and Computing. “It is an impressive example of how cutting-edge accelerator research can benefit society, and demonstrates the continuing links between the needs of fundamental research in particle physics and X-ray science.”

A full account of the European XFEL and its superconducting linac, which appeared in the CERN Courier July/August 2017 issue, can be read here: http://cerncourier.com/cws/article/cern/69335.

Related links:

European XFEL: http://www.xfel.eu/

LEP: http://home.cern/about/accelerators/large-electron-positron-collider

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

Images (mentioned), Text, Credits: CERN/Stefania Pandolfi.

Best regards, Orbiter.ch

vendredi 1 septembre 2017

Record-Setting NASA Astronaut, Crewmates Prepare for Return to Earth










ISS - Expedition 52 Mission patch.

September 1, 2017

Record-breaking NASA astronaut Peggy Whitson and her Expedition 52 crewmates, Flight Engineer Jack Fischer of NASA and Commander Fyodor Yurchikhin of the Russian space agency Roscosmos, are scheduled to depart the International Space Station and return to Earth Saturday, Sept. 2. NASA Television and the agency’s website will provide complete coverage of their departure and landing.

The trio will undock their Soyuz MS-04 spacecraft from the space station at 5:58 p.m. EDT and land in Kazakhstan at 9:22 p.m. (7:22 a.m. Sept. 3, Kazakhstan time). NASA astronaut Randy Bresnik has taken over command of the station from Yurchikhin.


Image above: Expedition 52 crew members (from left) Commander Fyodor Yurchikhin and Flight Engineers Jack Fischer and Peggy Whitson prepare the Sokol launch and entry suits they will wear when they undock and land in their Soyuz MS-04 spacecraft. Image Credit: NASA.

The complete schedule of return coverage is as follows (all times EDT):

- 2:15 p.m. – farewell and hatch closure (hatch closure at 2:40 p.m.)
- 5:30 p.m. – undocking (undocking at 5:58 p.m.)
- 8 p.m. – deorbit burn and landing (deorbit burn at 8:29 p.m. and landing at 9:22 p.m.)
- 11 p.m. – replay of hatch closure, undocking and landing activities

Keep up with the International Space Station, and its research and crew members, at: http://www.nasa.gov/station

Get breaking news, images, videos and features from the station on social media at:

    https://www.facebook.com/ISS
    http://instagram.com/iss
    https://twitter.com/space_station

As a result of the impacts of Hurricane Harvey, NASA plans a modified return to Houston of Whitson and Fischer and the science samples landing in the Soyuz spacecraft. The crew will participate in standard post-flight medical evaluations. Working with our International Space Station partners, NASA secured the services of ESA (European Space Agency) to return the crew from Karaganda, Kazakhstan, to Cologne, Germany.  NASA’s G-5 will depart Houston on Saturday to meet the crew and science samples in Cologne. They’re expected to return to Houston on Sunday night.  All necessary facilities onsite at NASA’s Johnson Space Center necessary to support crew and science objectives are being checked out, and readied for the return to Houston.


Image above: Expedition 52 Flight Engineer Peggy Whitson of NASA, Commander Fyodor Yurchikhin of the Russian space agency Roscosmos and Flight Engineer Jack Fischer of NASA float through the Harmony module of the International Space Station. Image Credit: NASA.

While living and working aboard the space station, the Expedition 52 crew pursued hundreds of experiments in biology, biotechnology, physical science and Earth science aboard humanity’s only orbiting laboratory.

Expedition 53 will begin when Whitson, Fischer and Yurchikhin depart with Randy Bresnik of NASA in command, and Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of ESA (European Space Agency), on board. The three-person crew will operate the station until the arrival of three new crew members later this month.

NASA astronauts Mark Vande Hei and Joe Acaba, and Alexander Misurkin of Roscosmos, are scheduled to launch Sept. 12 from Baikonur, Kazakhstan.

Related links:

Expedition 52: https://www.nasa.gov/mission_pages/station/expeditions/expedition52/index.html

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

Impacts of Hurricane Harvey: https://www.nasa.gov/press-release/nasa-s-johnson-space-center-closes-through-labor-day-for-tropical-storm-harvey

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

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

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

Greetings, Orbiter.ch

Hubble's Megamaser Galaxy











NASA - Hubble Space Telescope patch.

Sept. 1, 2017


Phenomena across the Universe emit radiation spanning the entire electromagnetic spectrum — from high-energy gamma rays, which stream out from the most energetic events in the cosmos, to lower-energy microwaves and radio waves.

Microwaves, the very same radiation that can heat up your dinner, are produced by a multitude of astrophysical sources, including strong emitters known as masers (microwave lasers), even stronger emitters with the somewhat villainous name of megamasers and the centers of some galaxies. Especially intense and luminous galactic centers are known as active galactic nuclei. They are in turn thought to be driven by the presence of supermassive black holes, which drag surrounding material inwards and spit out bright jets and radiation as they do so.

The two galaxies shown here, imaged by the NASA/ESA Hubble Space Telescope, are named MCG+01-38-004 (the upper, red-tinted one) and MCG+01-38-005 (the lower, blue-tinted one). MCG+01-38-005 (also known as NGC 5765B) is a special kind of megamaser; the galaxy’s active galactic nucleus pumps out huge amounts of energy, which stimulates clouds of surrounding water. Water’s constituent atoms of hydrogen and oxygen are able to absorb some of this energy and re-emit it at specific wavelengths, one of which falls within the microwave regime, invisible to Hubble but detectable by microwave telescopes. MCG+01-38-005 is thus known as a water megamaser!

Hubble Space Telescope

Astronomers can use such objects to probe the fundamental properties of the Universe. The microwave emissions from MCG+01-38-005 were used to calculate a refined value for the Hubble constant, a measure of how fast the Universe is expanding. This constant is named after the astronomer whose observations were responsible for the discovery of the expanding Universe and after whom the Hubble Space Telescope was named, Edwin Hubble.

For images and more information about Hubble, visit:

http://hubblesite.org/
http://www.nasa.gov/hubble
http://www.spacetelescope.org/

Image, Animation, Credits: ESA/Hubble & NASA/Text Credits: European Space Agency/NASA/Karl Hille.

Best regards, Orbiter.ch

NASA’s Asteroid-Bound Spacecraft to Slingshot Past Earth











NASA - OSIRIS-REx Mission patch.

Sept. 1, 2017

NASA’s asteroid sample return mission, OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security - Regolith Explorer), will pass about 10,000 miles (16,000 kilometers) above Earth just before 12:52 p.m. EDT on Friday, Sept. 22. Using Earth as a slingshot, the spacecraft will receive an assist to complete its journey to the asteroid Bennu.

OSIRIS-REx is undertaking a challenging mission to visit the near-Earth asteroid, survey the surface, collect samples and deliver them safely back to Earth. This is the first NASA mission to attempt such an undertaking. The spacecraft is halfway through its two-year outbound journey, and now OSIRIS-REx needs an extra boost to successfully rendezvous with Bennu.


Image above: This artist's concept shows the OSIRIS-REx spacecraft passing by Earth. Image Credits: NASA's Goddard Space Flight Center/University of Arizona.

Bennu’s orbit around the Sun is tilted six degrees in comparison to Earth’s. The gravity assist will change OSIRIS-REx’s trajectory to put the spacecraft on a course to match the asteroid’s path and speed.

“The Earth Gravity Assist is a clever way to move the spacecraft onto Bennu’s orbital plane using Earth’s own gravity instead of expending fuel,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. 

The team has already made multiple adjustments to the spacecraft’s path since launch on Sept. 8, 2016. The largest was a deep space maneuver on Dec. 28, 2016, that changed the speed and path of the spacecraft to target Earth for the flyby. There have also been three trajectory correction maneuvers – one on Oct. 7, 2016, one on Jan. 18, 2017, and another on Aug. 23, 2017 (30 days before the gravity assist) – that further refined the spacecraft’s trajectory in preparation for the flyby.

The navigation team comprises employees from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and KinetX Aerospace. KinetX Aerospace navigation team members plan and carry out all OSIRIS-REx maneuvers with the Lockheed Martin spacecraft operations team at the Lockheed Martin Waterton Campus in Littleton, Colorado. To properly target the Earth Gravity Assist, the navigation team calculates any required amount of change in the spacecraft’s course and speed. This information is then translated by the operations team into commands that are uploaded to the spacecraft and executed by firing the spacecraft’s rocket engines.

After traveling almost 600 million miles, OSIRIS-REx will approach Earth at a speed of about 19,000 mph. The spacecraft will fly over Australia before reaching its closest point to Earth over Antarctica, just south of Cape Horn, Chile.

“For about an hour, NASA will be out of contact with the spacecraft as it passes over Antarctica,” said Mike Moreau, the flight dynamics system lead at Goddard. “OSIRIS-REx uses the Deep Space Network to communicate with Earth, and the spacecraft will be too low relative to the southern horizon to be in view with either the Deep Space tracking station at Canberra, Australia, or Goldstone, California.”

NASA will regain communication with OSIRIS-REx at 1:40 p.m. EDT, roughly 50 minutes after closest approach.

At 4:52 p.m. EDT, four hours after closest approach, OSIRIS-REx will begin science observations of Earth and the Moon to calibrate its instruments.

During the gravity assist, OSIRIS-REx will pass through a region of space that is inhabited by Earth-orbiting satellites, and NASA has taken precautions to ensure the safety of the spacecraft as it flies through this area. The mission’s flight dynamics team designed a small maneuver that, if necessary, could be executed a day before closest approach to change the spacecraft’s trajectory slightly to avoid a potential collision between OSIRIS-REx and a satellite.

“A few weeks after the flyby we will assess the outgoing trajectory on its way to Bennu,” said Dan Wibben, the maneuver design and trajectory analysis lead from KinetX Aerospace. “There is a maneuver planned in case we need to adjust the orbit just a little bit to push the spacecraft back on track.”

In late June of 2018, the team will perform another deep space maneuver to further target the rendezvous with Bennu. Then beginning in October 2018, a series of asteroid approach maneuvers will be executed to slow the spacecraft with respect to the asteroid.

Once OSIRIS-REx rendezvous with Bennu in late 2018, the spacecraft will begin surveying the surface.

“The asteroid’s small size and low gravity makes OSIRIS-REx the most challenging mission that I have worked on,” said Peter Antreasian, the navigation team chief from KinetX Aerospace. “At roughly 500 meters in diameter, Bennu will be the smallest object that NASA has orbited.”

OSIRIS-REx mission to the asteroid Bennu. Animation Credit: NASA

While the engineering team is busy carrying out the Earth Gravity Assist, the mission invites members of the public to mark the occasion by participating in the Wave to OSIRIS-REx social media campaign. Individuals and groups from anywhere in the world are encouraged to take photos of themselves waving to OSIRIS-REx, share them using the hashtag #HelloOSIRISREx and tag the mission account in their posts on Twitter (@OSIRISREx) or Instagram (@OSIRIS_REx).

Participants may begin taking and sharing photos at any time—or wait until the OSIRIS-REx spacecraft makes its closest approach to Earth at 12:52p.m. EDT on Friday, Sept. 22.

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

For more information about the OSIRIS-REx mission, visit: http://www.nasa.gov/osiris-rex

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

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Karl Hille/Goddard Space Flight Center, by Jordan Rice.

Greetings, Orbiter.ch

Hubble delivers first hints of possible water content of TRAPPIST-1 planets












ESA - Hubble Space Telescope logo.

Sept.1, 2017

Artist’s impression of the TRAPPIST-1 planetary system

An international team of astronomers used the NASA/ESA Hubble Space Telescope to estimate whether there might be water on the seven earth-sized planets orbiting the nearby dwarf star TRAPPIST-1. The results suggest that the outer planets of the system might still harbour substantial amounts of water. This includes the three planets within the habitable zone of the star, lending further weight to the possibility that they may indeed be habitable.

On 22 February 2017 astronomers announced the discovery of seven Earth-sized planets orbiting the ultracool dwarf star TRAPPIST-1, 40 light-years away [1]. This makes TRAPPIST-1 the planetary system with the largest number of Earth-sized planets discovered so far.

Comparison between the Sun and the ultracool dwarf star TRAPPIST-1

Following up on the discovery, an international team of scientists led by the Swiss astronomer Vincent Bourrier from the Observatoire de l’Université de Genève, used the Space Telescope Imaging Spectrograph (STIS) on the NASA/ESA Hubble Space Telescope to study the amount of ultraviolet radiation received by the individual planets of the system. “Ultraviolet radiation is an important factor in the atmospheric evolution of planets,” explains Bourrier. “As in our own atmosphere, where ultraviolet sunlight breaks molecules apart, ultraviolet starlight can break water vapour in the atmospheres of exoplanets into hydrogen and oxygen.”

While lower-energy ultraviolet radiation breaks up water molecules — a process called photodissociation — ultraviolet rays with more energy (XUV radiation) and X-rays heat the upper atmosphere of a planet, which allows the products of photodissociation, hydrogen and oxygen, to escape.

Comparing the TRAPPIST-1 planets

As it is very light, hydrogen gas can escape the exoplanets’ atmospheres and be detected around the exoplanets with Hubble, acting as a possible indicator of atmospheric water vapour [2]. The observed amount of ultraviolet radiation emitted by TRAPPIST-1 indeed suggests that the planets could have lost gigantic amounts of water over the course of their history.

This is especially true for the innermost two planets of the system, TRAPPIST-1b and TRAPPIST-1c, which receive the largest amount of ultraviolet energy. “Our results indicate that atmospheric escape may play an important role in the evolution of these planets,” summarises Julien de Wit, from MIT, USA, co-author of the study.

Seven planets orbiting the ultracool dwarf star TRAPPIST-1

The inner planets could have lost more than 20 Earth-oceans-worth of water during the last eight billion years. However, the outer planets of the system — including the planets e, f and g which are in the habitable zone — should have lost much less water, suggesting that they could have retained some on their surfaces [3]. The calculated water loss rates as well as geophysical water release rates also favour the idea that the outermost, more massive planets retain their water. However, with the currently available data and telescopes no final conclusion can be drawn on the water content of the planets orbiting TRAPPIST-1.

“While our results suggest that the outer planets are the best candidates to search for water with the upcoming James Webb Space Telescope, they also highlight the need for theoretical studies and complementary observations at all wavelengths to determine the nature of the TRAPPIST-1 planets and their potential habitability,” concludes Bourrier.

Animation of the planets orbiting TRAPPIST-1

Notes:

[1] The planets were discovered using: the ground-based TRAPPIST-South at ESO’s La Silla Observatory in Chile; the orbiting NASA Spitzer Space Telescope; TRAPPIST-North in Morocco; ESO’s HAWK-I instrument on the Very Large Telescope at the Paranal Observatory in Chile; the 3.8-metre UKIRT in Hawaii; the 2-metre Liverpool and 4-metre William Herschel telescopes at La Palma in the Canary Islands; and the 1-metre SAAO telescope in South Africa.

[2] This part of an atmosphere is called the exosphere. Earth’s exosphere consists mainly of hydrogen with traces of helium, carbon dioxide and atomic oxygen.

[3] Results show that each of these planets have may have lost less than three Earth-oceans of water.

More information:

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

The team of the study is composed of V. Bourrier (Observatoire de l’Université de Genève, Switzerland), J. de Witt (Massachusetts Institute of Technology, USA), E. Bolmont (Laboratoire AIM Paris-Saclay), V. Stamenkovic (Jet Propulsion Laboratory, USA; California Institute of Technology, USA), P. J. Wheatley (University of Warwick, UK), A. J. Burgasser (University of California San Diego, USA), L. Delrez (Cavendish Laboratory, UK), B.-O. Demory (University of Bern, Switzerland), D. Ehrenreich (Observatoire de l’Université de Genève, Switzerland), M. Gillon (Université de Liège, Belgium), E. Jehin (Université de Liège, Belgium), J. Leconte (Université Bordeaux, France), S. M. Lederer (NASA Johnson Space Center, USA), N. Lewis (Space Telescope Science Institute, USA), A. H. M. J. Triaud A. H. M. J. Triaud (Institute of Astronomy, Cambridge, UK, now at University of Birmingham, UK) and V. van Grootel (Université de Liege, Belgium)

Links:

ESA's Hubble website: https://www.spacetelescope.org/

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

ESO release on the discovery of the planets: http://www.eso.org/public/news/eso1706/

Science paper:
http://www.spacetelescope.org/static/archives/releases/science_papers/heic1713/heic1713a.pdf

Webpage on TRAPPIST-1: http://www.trappist.one/

University Geneva press release (french): https://www.unige.ch/communication/communiques/2017/cdp300817/

Space Telescope Imaging Spectrograph (STIS): https://www.spacetelescope.org/about/general/instruments/stis/

Very Large Telescope (VLT) at the Paranal Observatory: http://www.eso.org/public/teles-instr/vlt/?lang

ESO’s HAWK-I: http://www.eso.org/public/teles-instr/vlt/vlt-instr/hawk-i/

NASA Spitzer Space Telescope: http://www.spitzer.caltech.edu/

William Herschel telescopes: http://astrolapalma.com/en/william-herschel-telescope

UKIRT: http://www.ukirt.hawaii.edu/

SAAO telescope: http://www.saao.ac.za/science/facilities/telescopes/

Images, Video, Text, Credits: NASA, ESA, ESO/N. Bartmann/spaceengine.org/R. Hurt/T. Pyle//L. Calçada.

Best regards, Orbiter.ch

jeudi 31 août 2017

New Mission Going to the Space Station to Explore Mysteries of 'Cosmic Rain'














ISS - International Space Station patch / ISS- Cosmic Ray Energetics and Mass (ISS-CREAM) patch.

Aug. 31, 2017


Image above: From its new vantage point on the International Space Station's Japanese Experiment Module - Exposed Facility, the Cosmic Ray Energetics and Mass (ISS-CREAM) mission, shown in the inset illustration, will study cosmic rays to determine their sources and acceleration mechanisms. Image Credit: NASA.

A new experiment set for an Aug. 14 launch to the International Space Station will provide an unprecedented look at a rain of particles from deep space, called cosmic rays, that constantly showers our planet. The Cosmic Ray Energetics And Mass mission destined for the International Space Station (ISS-CREAM) is designed to measure the highest-energy particles of any detector yet flown in space.

CREAM was originally developed as a part of NASA's Balloon Program, during which it returned measurements from around 120,000 feet in seven flights between 2004 and 2016.

Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM)

Video above: Meet Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM), an experiment designed to provide an unprecedented look at cosmic ray particles approaching energies of 1,000 trillion electron volts (1 PeV). ISS-CREAM detects these particles when they slam into the matter making up its instruments. They can distinguish electrons, protons and atomic nuclei as massive as iron as they crash through the detector stack. Image Credits: NASA's Goddard Space Flight Center.

"The CREAM balloon experiment achieved a total sky exposure of 191 days, a record for any balloon-borne astronomical experiment," said Eun-Suk Seo, a professor of physics at the University of Maryland in College Park and the experiment's principal investigator. "Operating on the space station will increase our exposure by over 10 times, taking us well beyond the traditional energy limits of direct measurements."

Sporting new instruments, as well as refurbished versions of detectors originally used on balloon flights over Antarctica, the refrigerator-sized, 1.4-ton (1,300 kilogram) ISS-CREAM experiment will be delivered to the space station as part of the 12th SpaceX commercial resupply service mission. Once there, ISS-CREAM will be moved to the Exposed Facility platform extending from Kibo, the Japanese Experiment Module.

From this orbital perch, ISS-CREAM is expected to study the "cosmic rain" for three years — time needed to provide unparalleled direct measurements of rare high-energy cosmic rays.


Image above: Technicians lower ISS-CREAM into a chamber that simulates the space environment during system-level testing at NASA's Goddard Space Flight Center in summer 2015. Image Credits: University of Maryland Cosmic Ray Physics Laboratory.

At energies above about 1 billion electron volts, most cosmic rays come to us from beyond our solar system. Various lines of evidence, including observations from NASA's Fermi Gamma-ray Space Telescope, support the idea that shock waves from the expanding debris of stars that exploded as supernovas accelerate cosmic rays up to energies of 1,000 trillion electron volts (PeV). That's 10 million times the energy of medical proton beams used to treat cancer. ISS-CREAM data will allow scientists to examine how sources other than supernova remnants contribute to the population of cosmic rays.

Protons are the most common cosmic ray particles, but electrons, helium nuclei and the nuclei of heavier elements make up a small percentage. All are direct samples of matter from interstellar space. But because the particles are electrically charged, they interact with galactic magnetic fields, causing them to wander in their journey to Earth. This scrambles their paths and makes it impossible to trace cosmic ray particles back to their sources.

"An additional challenge is that the flux of particles striking any detector decreases steadily with higher energies," said ISS-CREAM co-investigator Jason Link, a researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "So to better explore higher energies, we either need a much bigger detector or much more observing time. Operating on the space station provides us with this extra time."


Image above: The ISS-CREAM payload was delivered to NASA's Kennedy Space Center in August 2015. The experiment is shown wrapped in plastic layers used to protect its sensitive electronics during shipment. Image Credits: University of Maryland Cosmic Ray Physics Laboratory.

Large ground-based systems study cosmic rays at energies greater than 1 PeV by making Earth's atmosphere the detector. When a cosmic ray strikes the nucleus of a gas molecule in the atmosphere, both explode in a shower of subatomic shrapnel that triggers a wider cascade of particle collisions. Some of these secondary particles reach detectors on the ground, providing information scientists can use to infer the properties of the original cosmic ray.

These secondaries also produce an interfering background that limited the effectiveness of CREAM's balloon operations. Removing that background is another advantage of relocating to orbit.

With decreasing numbers of particles at increasing energies, the cosmic ray spectrum vaguely resembles the profile of a human leg. At PeV energies, this decline abruptly steepens, forming a detail scientists call the "knee." ISS-CREAM is the first space mission capable of measuring the low flux of cosmic rays at energies approaching the knee.

"The origin of the knee and other features remain longstanding mysteries," Seo said. "Many scenarios have been proposed to explain them, but we don't know which is correct."

Astronomers don't think supernova remnants are capable of powering cosmic rays beyond the PeV range, so the knee may be shaped in part by the drop-off of their cosmic rays in this region.

"High-energy cosmic rays carry a great deal of information about our interstellar neighborhood and our galaxy, but we haven't been able to read these messages very clearly," said co-investigator John Mitchell at Goddard. "ISS-CREAM represents one significant step in this direction."


Image above: ISS-CREAM (center) is seen attached to the space station's robotic arm during the experiment's installation on Aug. 21. Image Credit: NASA.

ISS-CREAM detects cosmic ray particles when they slam into the matter making up its instruments. First, a silicon charge detector measures the electrical charge of incoming particles, then layers of carbon provide targets that encourage impacts, producing cascades of particles that stream into electrical and optical detectors below while a calorimeter determines their energy. Two scintillator-based detector systems provide the ability to discern between singly charged electrons and protons. All told, ISS-CREAM can distinguish electrons, protons and atomic nuclei as massive as iron as they crash through the instruments.

ISS-CREAM will join two other cosmic ray experiments already working on the space station. The Alpha Magnetic Spectrometer (AMS-02), led by an international collaboration sponsored by the U.S. Department of Energy, is mapping cosmic rays up to a trillion electron volts, and the Japan-led Calorimetric Electron Telescope (CALET), also located on the Kibo Exposed Facility, is dedicated to studying cosmic ray electrons.

ScienceCasts: The Mystery of High-Energy Cosmic Rays

Video above: Credits: NASA.

Overall management of ISS-CREAM and integration for its space station application was provided by NASA’s Wallops Flight Facility on Virginia’s Eastern Shore. ISS-CREAM was developed as part of an international collaboration led by the University of Maryland at College Park, which includes teams from NASA Goddard, Penn State University in University Park, Pennsylvania, and Northern Kentucky University in Highland Heights, as well as collaborating institutions in the Republic of Korea, Mexico and France.

Editor's note, Aug. 31, 2017:

The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is installed on the Japanese Experiment Module - Exposed Facility and was powered up on Tuesday, Aug. 22. The science team is now tuning and commissioning the experiment.

"Our collaborators in the U.S. and abroad are looking at the data to tune each detector system," said Principal Investigator Eun-suk Seo at the University of Maryland in College Park. "We have to monitor over 1,500 parameters in the housekeeping data alone, but the data we are receiving show nominal instrument status."

Once ISS-CREAM fully checks out, it will begin a planned mission of one to three years of collecting data on high-energy cosmic ray particles from interstellar space moving at nearly the speed of light.

Related links:

Cosmic Ray Energetics and Mass (ISS-CREAM): http://cosmicray.umd.edu/cream/

Exposed Facility: https://www.nasa.gov/multimedia/imagegallery/image_feature_1430.html

Alpha Magnetic Spectrometer (AMS-02): https://ams.nasa.gov/

Calorimetric Electron Telescope (CALET): https://www.nasa.gov/mission_pages/station/research/news/calet

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), Videos (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Francis Reddy.

Greetings, Orbiter.ch

ISRO's Eighth Navigation Satellite IRNSS-1H Unsuccessful Mission











ISRO - Indian Space Research Organisation logo.


August 31, 2017

 ISRO's Eighth Navigation Satellite IRNSS-1H Lifts-off (Illustration by ISRO)

Mission Director has authorised Vehicle Director for launch. Automatic Launch Sequence (ALS) program initiation authorised by Vechicle Director and ALS started for launch of PSLV-C39/IRNSS-1H Satellite mission at 18:47 hr IST.

The forty first flight of India’s Polar Satellite Launch Vehicle (PSLV-C39), conducted today (August 31, 2017) evening from Satish Dhawan Space Centre SHAR, Sriharikota, was unsuccessful.  PSLV-C39 had a normal lift-off at 1900 hrs IST (7:00 pm) and all the flight events took place exactly as planned, except heat shield separation.

ISRO's Eighth Navigation Satellite IRNSS-1H Successfully Lifts-off aboard PSLV-C39

This resulted in satellite separation occurring within the heat shield.  The satellite is inside the heat shield resulting in the unsuccessful mission. Detailed analysis is under progress to identify the cause of the anomaly in the heat shield separation event.

IRNSS-1H Satellite

The Polar Satellite Launch Vehicle, in its forty-first flight (PSLV-C39), will launch IRNSS-1H, the eighth satellite of the Indian Regional Navigation Satellite System (IRNSS) into a Sub-Geosynchronous Transfer Orbit (Sub-GTO). The launch will take place from the Second Launch Pad (SLP) of Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota. As in the previous six launches of IRNSS satellites, PSLV-C39 will use ‘XL’ version of PSLV equipped with six strap-ons, each carrying 12 tons of propellant.

For more information about the mission and Indian Space Research Organisation (ISRO), visit: http://www.isro.gov.in/

Images, Text, Credits: ISRO/HMTV/Orbiter.ch Aerospace.

Greetings, Orbiter.ch

Close encounters of the stellar kind












ESA - Gaia Mission patch.

31 August 2017

The movements of more than 300 000 stars surveyed by ESA’s Gaia satellite reveal that rare close encounters with our Sun might disturb the cloud of comets at the far reaches of our Solar System, sending some towards Earth in the distant future.

As the Solar System moves through the Galaxy, and as other stars move on their own paths, close encounters are inevitable – though ‘close’ still means many trillions of kilometres.

A star, depending on its mass and speed, would need to get within about 60 trillion kilometres before it starts to have an effect on the Solar System’s distant reservoir of comets, the Oort Cloud, which is thought to extend out to 15 trillion kilometres from the Sun, 100 000 times the Sun–Earth distance.

Waiting for a stellar encounter

For comparison, the outermost planet Neptune orbits at an average distance of about 4.5 billion kilometres, or 30 Sun–Earth distances.

The gravitational influence of stars that pass near the Oort Cloud could perturb the paths of comets residing there, jolting them onto orbits that bring them in to the inner Solar System.

While this is thought to be responsible for some of the comets that appear in our skies every hundred to thousand years, it also has the potential to put comets on a collision course with Earth or other planets.

Tracking stellar motions

Understanding the past and future motions of stars is a key goal of Gaia as it collects precise data on stellar positions and motions over its five-year mission. After 14 months, the first catalogue of more than a billion stars was recently released, which included the distances and the motions across the sky for more than two million stars.

By combining the new results with existing information, astronomers began a detailed, large-scale search for stars passing close to our Sun. 

So far, the motions relative to the Sun of more than 300 000 stars have been traced through the Galaxy and their closest approach determined for up to five million years in the past and future.

Of them, 97 stars were found that will pass within 150 trillion kilometres, while 16 come within about 60 trillion km.

While the 16 are considered reasonably near, a particularly close encounter of one star, Gliese 710, in 1.3 million years’ time, stands out. It is predicted to pass within just 2.3 trillion km or about 16 000 Earth–Sun distances, well within the Oort Cloud.

The star is already well-documented, and thanks to the Gaia data, the estimated encounter distance has recently been revised. Previously, there was a 90% degree of certainty that it would come within 3.1–13.6 trillion kilometres. Now, the more accurate data suggest that it will come within 1.5–3.2 trillion km, with 2.3 trillion km most likely.

Gaia

Furthermore, although Gliese 710 has a mass of 60% that of our Sun, it travels much slower than most stars: nearly 50 000 km/h at closest approach, compared with the average 100 000 km/h.

The speed of its passage means it will have plenty of time to exert its gravitational influence on bodies in the Oort Cloud, potentially sending showers of comets into the Solar System.

Despite its slower pace, it will still appear as the brightest, fastest object in the night sky at closest approach.

Importantly, the latest study used Gaia measurements to make a general estimate of the rate of stellar encounters, taking into account uncertainties such as stars that might not have been observable in the existing catalogue.

For 5 million years in the past and into the future, the overall encounter rate is estimated to be around 550 stars per million years coming within 150 trillion km, of which about 20 would come closer than 30 trillion km.

That equates to about one potential ‘close’ encounter every 50 000 years or so. It is important to note that it is not guaranteed that a star would actually perturb any comets such that they entered the inner regions of the Solar System, and even if they did, if Earth would be in the firing line.

These estimates will be refined with future Gaia data releases. The second is scheduled for next April, containing the information for about 20 times as many stars, and many more distant stars as well, allowing reconstructions up to 25 million years into the past and future.

Notes for Editors

“The completeness-corrected rate of stellar encounters with the Sun from the first Gaia data release,” by C.A.L. Bailer-Jones, is published in Astronomy & Astrophysics.
https://www.aanda.org/component/article?access=doi&doi=10.1051/0004-6361/201731453

More information also available via: Close stellar encounters from the first Gaia data release: https://www.cosmos.esa.int/web/gaia/iow_20170831

ESA's Gaia mission: http://www.esa.int/Our_Activities/Space_Science/Gaia

Gaia overview: http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_overview

Gaia factsheet: http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_factsheet

Frequently asked questions: http://www.esa.int/Our_Activities/Space_Science/Gaia/Frequently_Asked_Questions_about_Gaia

Gaia brochure: http://www.esa.int/About_Us/ESA_Publications/ESA_BR-296_Gaia_ESA_s_galactic_census

Hipparcos mission: http://sci.esa.int/science-e/www/area/index.cfm?fareaid=20

Image, Videos, Text, Credits: ESA/Markus Bauer/Timo Prusti/Max Planck Institute for Astronomy/Coryn Bailer-Jones/Gaia/DPAC.

Best regards, Orbiter.ch

mercredi 30 août 2017

ALMA Finds Huge Hidden Reservoirs of Turbulent Gas in Distant Galaxies












ALMA - Atacama Large Millimeter/submillimeter Array logo.

30 August 2017

First detection of CH+ molecules in distant starburst galaxies provides insight into star formation history of the Universe

Artist’s impression of gas fueling distant starburst galaxies

ALMA has been used to detect turbulent reservoirs of cold gas surrounding distant starburst galaxies. By detecting CH+ for the first time in the distant Universe this research opens up a new window of exploration into a critical epoch of star formation. The presence of this molecule sheds new light on how galaxies manage to extend their period of rapid star formation. The results appear in the journal Nature.

A team led by Edith Falgarone (Ecole Normale Supérieure and Observatoire de Paris, France) has used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect signatures of the carbon hydride molecule CH+ [1] in distant starburst galaxies [2]. The group identified strong signals of CH+ in five out of the six galaxies studied, including the Cosmic Eyelash (eso1012) [3]. This research provides new information that helps astronomers understand the growth of galaxies and how a galaxy’s surroundings fuel star formation.

“CH+ is a special molecule. It needs a lot of energy to form and is very reactive, which means its lifetime is very short and it can’t be transported far. CH+ therefore traces how energy flows in the galaxies and their surroundings,” said Martin Zwaan, an astronomer at ESO, who contributed to the paper.

ALMA view of the Cosmic Eyelash

How CH+ traces energy can be thought of by analogy to being on a boat in a tropical ocean on a dark, moonless night. When the conditions are right, fluorescent plankton can light up around the boat as it sails. The turbulence caused by the boat sliding through the water excites the plankton to emit light, which reveals the existence of the the turbulent regions in the underlying dark water. Since CH+ forms exclusively in small areas where turbulent motions of gas dissipates, its detection in essence traces energy on a galactic scale.

The observed CH+ reveals dense shock waves, powered by hot, fast galactic winds originating inside the galaxies’ star forming regions. These winds flow through a galaxy, and push material out of it, but their turbulent motions are such that part of the material can be re-captured by the gravitational pull of the galaxy itself. This material gathers into huge turbulent reservoirs of cool, low-density gas, extending more than 30 000 light-years from the galaxy’s star forming region [4].

“With CH+, we learn that energy is stored within vast galaxy-sized winds and ends up as turbulent motions in previously unseen reservoirs of cold gas surrounding the galaxy,” said Falgarone, who is lead author of the new paper. “Our results challenge the theory of galaxy evolution. By driving turbulence in the reservoirs, these galactic winds extend the starburst phase instead of quenching it.”

Zooming in on the Cosmic Eyelash

The team determined that galactic winds alone could not replenish the newly revealed gaseous reservoirs and suggests that the mass is provided by galactic mergers or accretion from hidden streams of gas, as predicted by current theory.

“This discovery represents a major step forward in our understanding of how the inflow of material is regulated around the most intense starburst galaxies in the early Universe,” says ESO’s Director for Science, Rob Ivison, a co-author on the paper. “It shows what can be achieved when scientists from a variety of disciplines come together to exploit the capabilities of the world's most powerful telescope.”

Notes:

[1] CH+ is an ion of the CH molecule known as methylidynium to chemists. It is one of the first three molecules ever discovered in the interstellar medium. Since its discovery in the early 1940s, the presence of CH+ in interstellar space has been a mystery because it is extremely reactive and hence disappears more quickly than other molecules.

[2] These galaxies are known for a much higher rate of star formation compared to sedate Milky Way-like galaxies, making these structures ideal to study galaxy growth and the interplay between gas, dust, stars, and the black holes at the centres of galaxies.

[3] ALMA was used to obtain spectra of each galaxy. A spectrum is a record of light, typically of an astronomical object, split into its different colours (or wavelengths), in much the same way that rain droplets disperse light to form a rainbow. Since every element has a unique “fingerprint” in a spectrum, spectra can be used to determine the chemical composition of observed objects.

[4] These turbulent reservoirs of diffuse gas may be of the same nature as the giant glowing haloes seen around distant quasars.

More information:

This research was presented in a paper entitled “Large turbulent reservoirs of cold molecular gas around high redshift starburst galaxies” by E. Falgarone et al., to appear in Nature on 30 August 2017.

The team is composed of E. Falgarone (Ecole Normale Supérieure and Observatoire de Paris, France), M.A. Zwaan (ESO, Germany), B. Godard (Ecole Normale Supérieure and Observatoire de Paris, France), E. Bergin (University of Michigan, USA), R.J. Ivison (ESO, Germany; University of Edinburgh, UK), P. M. Andreani (ESO, Germany), F. Bournaud (CEA/AIM, France), R. S. Bussmann (Cornell University, USA), D. Elbaz (CEA/AIM, France), A. Omont (IAP, CNRS, Sorbonne Universités, France), I. Oteo (University of Edinburgh, UK; ESO, Germany) and F. Walter (Max-Planck-Institut für Astronomie, Germany).

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.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. 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. 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:

eso1012: https://www.eso.org/public/news/eso1012/

Research paper in Nature: https://www.eso.org/public/archives/releases/sciencepapers/eso1727/eso1727a.pdf

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

Atacama Large Millimeter/submillimeter Array (ALMA): http://eso.org/alma

Images, Text, Credits: ESO/Richard Hook/L. Benassi/Ecole Normale Supérieure — Observatoire de Paris/Edith Falgarone/ALMA (ESO/NAOJ/NRAO)/E. Falgarone et al./Video: ALMA (ESO/NAOJ/NRAO), Digitized Sky Survey 2, ESA/Hubble. Music: Astral Electronic.

Best regards, Orbiter.ch

NASA Shows How Harvey Saturated Areas in Texas














NASA - SMAP Mission patch / NASA - Suomi NPP Mission logo / NOAA & NASA - GOES Mission logo.

Aug. 30, 2017

Harvey (was TD 09 - Atlantic Ocean)

NASA analyzed the soil moisture in southeastern Texas before and after Harvey made landfall and found the ground was already somewhat saturated. NASA-NOAA’s Suomi NPP Satellite provided a night-time look at Harvey after it moved into the Gulf of Mexico, and NOAA’s GOES East satellite provided a look at the storm after it made its final landfall near the Texas-Louisiana border on Aug. 30.


Image above: SMAP observations in southeastern Texas on Aug. 21 & 22 show that soil surface conditions were very wet a few days before (left) Harvey made landfall, with moisture levels in the 20 to 40 percent range. After Harvey made landfall, the southwest portion of Houston became exceptionally wet (right) by Aug.25 & 26, signaling the arrival of heavy rains and widespread flooding. Image Credits: NASA JPL.

NASA Looks at Soil Moisture

At NASA's Jet Propulsion Laboratory in Pasadena, Calif. images of soil moisture conditions in Texas near Houston, were generated using data from NASA's Soil Moisture Active Passive (SMAP) satellite. The images captured conditions before and after the landfall of Hurricane Harvey. The images can be used to monitor changing ground conditions due to Harvey's rainfall.

SMAP observations from Aug. 21 and 22 showed that soil surface conditions were already very wet a few days before the hurricane made landfall, with moisture levels in the 20 to 40 percent range. Such saturated soil surfaces contributed to the inability of water to infiltrate more deeply into soils, thereby increasing the likelihood of flooding. After Harvey made landfall, the southwest portion of Houston became exceptionally wet. SMAP captured data on Aug. 25 and 26 that signaled the arrival of heavy rains and widespread flooding.

A Night-time View

On Aug. 29 at 3:03 a.m. CDT the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite captured a night-time image of Harvey that showed the center of circulation had moved back into the Gulf of Mexico.


Image above: On Aug. 29 at 3:03 a.m. CDT the VIIRS instrument aboard NASA-NOAA’s Suomi NPP satellite captured a night-time image of Harvey that showed the center of circulation had moved back into the Gulf of Mexico. Image Credits: NASA/NOAA/UWM-CIMSS, William Straka III.

Harvey Makes Another Landfall

NOAA’s GOES-East satellite provided a visible-light image of Tropical Storm Harvey on Wednesday, August 30, 2017 at 7:30 a.m. EDT (1230 UTC), hours after it made landfall at 4 a.m. CDT just west of Cameron, Louisiana. At the time of the image, the bulk of showers and thunderstorms around Harvey seemed to stretch from the northern to southwestern quadrants of the storm.


Image above: NOAA’s GOES-East satellite provided a visible-light image of Tropical Storm Harvey on Wednesday, August 30, 2017 at 7:30 a.m. EDT (1230 UTC) after it made landfall at 4 a.m. CDT just west of Cameron, Louisiana. Image Credits: NASA/NOAA GOES Project.

NHC noted “Although the rain has ended in the Houston/Galveston area, the Beaumont/Port Arthur area was particularly hard hit overnight, with about 12.5 inches reported at the Jack Brooks Regional Airport since 7 p.m. CDT on Aug. 29.”

The NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland created an image. NOAA manages the GOES series of satellites and the NASA/NOAA GOES Project creates images and animations from the data.

Warnings and Watches in Effect on Aug. 30 at 7 a.m. CDT

The National Hurricane Center (NHC) said a Storm Surge Warning is in effect for Holly Beach, Louisiana to Morgan City, Louisiana. A Storm Surge Watch is in effect from east of High Island, Texas to west of Holly Beach, Louisiana. A Tropical Storm Warning is in effect from east of High Island, Texas to Grand Isle, Louisiana. Catastrophic and life-threatening flooding continues in southeastern Texas and portions of southwestern Louisiana. 

Harvey’s Location on Aug. 30 at 7 a.m. CDT

At 7 a.m. CDT (1200 UTC), the center of Tropical Storm Harvey was located over southwestern Louisiana near 30.2 degrees north latitude and 93.6 degrees west longitude.

Harvey has been moving toward the north at about 9 mph (14 kph) for the past several hours.  The storm is expected to move north-northeastward later this morning, and then a northeastward motion at a faster forward speed is expected through Thursday night.  On the forecast track, the center of Harvey will move across the Lower Mississippi Valley and Tennessee Valley through Thursday.

Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. Gradual weakening is forecast as the center moves farther inland, and Harvey is expected to become a tropical depression by tonight. The estimated minimum central pressure based on surface observations is 992 millibars.

More Heavy Rainfall Expected

NHC said Harvey is expected to produce additional rainfall accumulations of 3 to 6 inches from southwestern Louisiana and the adjacent border of eastern Texas northeastward into western Kentucky through Friday with isolated amounts up to 10 inches. The expected heavy rains spreading northeastward from Louisiana into western Kentucky may also lead to flash flooding and increased river and small stream flooding.

Elsewhere, the outer bands of Harvey are expected to produce additional rainfall amounts of 3 to 6 inches over portions of the central and eastern Gulf States and 2 to 4 inches farther north into parts of the Tennessee Valley through Friday, Sept. 1. These rains may lead to flooding concerns across these areas.

NHC noted “While the threat of heavy rains has ended in the Houston/Galveston area, catastrophic and life-threatening flooding will continue in and around Houston eastward into southwest Louisiana for the rest of the week.”

A list of rainfall observations compiled by the NOAA Weather Prediction Center can be found at: http://www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

For forecast updates on Harvey, visit: http://www.nhc.noaa.gov/

NASA SMAP: https://smap.jpl.nasa.gov/

NOAA’s GOES-East: http://www.goes.noaa.gov/

NASA-NOAA’s Suomi NPP: https://www.nasa.gov/mission_pages/NPP/mission_overview/index.html

Images (mentioned), Text, Credits: NASA/JPL/Goddard Space Flight Center, by Rob Gutro/Karen Boggs.

Greetings, Orbiter.ch

mardi 29 août 2017

NASA's GPM & IMERG Shows Rainfall Accumulation Along Harvey's Track













NASA & JAXA - Global Precipitation Measurement (GPM) patch.

Aug. 29, 2017

Harvey (was TD 09 - Atlantic Ocean)

As Harvey continues to dump catastrophic rains over southeastern Texas and southwestern Louisiana, NASA has been tallying rainfall accumulations in the storm's wake.


Image above: IMERG data for Harvey were compiled for the period from August 23 to 29, 2017 as it moved through the Gulf of Mexico and stalled over Texas. The IMERG totals showed over 30 inches of rainfall had occurred in the Houston metro area and part of the western Gulf of Mexico. Image Credits: NASA JAXA, Hal Pierce.

Total rainfall estimates from NASA's Integrated Multi-satellitE Retrievals for GPM (IMERG) data were compiled for the period from August 23 to 29, 2017. During this period Harvey dropped heavy rainfall as it moved through the Gulf of Mexico and stalled over Texas. The IMERG totals showed over 30 inches of rainfall had occurred in the Houston metro area and part of the western Gulf of Mexico.

It has been reported that Harvey dropped over 40 inches (1016 mm) of rain over southeastern Texas during this period. IMERG Data are produced at NASA's Goddard Space Flight Center in Greenbelt, Maryland, using data from the satellites in the Global Precipitation Measurement mission or GPM Constellation, and is calibrated with measurements from the GPM Core Observatory as well as rain gauge networks around the world. 

The National Weather Service reported at 1 p.m. CDT on Aug. 29 "A preliminary report from one Texas rain gauge has broken the Texas tropical cyclone rainfall record. Southeast of Houston, Mary's Creek at Winding Road reported 49.32 inches as of 9 a.m. CDT. This total is higher than the previous record of 48 inches set during tropical cyclone Amelia of 1978 at Medina, Texas."

The National Hurricane Center (NHC) indicates that Harvey continues to drop heavy rain over southeastern Texas and southern Louisiana as it moves toward the north-northeast. 

Warnings and Watches in Effect as of 1 p.m. CDT, Aug. 29

The NHC said a Tropical Storm Warning is in effect from nNorth of Port O'Connor, Texas to Morgan City, Louisiana. A Tropical Storm Watch is in effect from east of Morgan City to Grand Isle, Louisiana. A Storm Surge Watch is in effect from Port Bolivar, Texas to Morgan City.

IMERG Data on Rainfall From Harvey

Video above: This animation of IMERG data for Harvey were compiled for the period from August 23 to 29, 2017 as it moved through the Gulf of Mexico and stalled over Texas. The IMERG totals showed over 30 inches of rainfall had occurred in the Houston metro area and part of the western Gulf of Mexico. Video Credits: NASA JAXA, Hal Pierce.

More Heavy Rainfall Expected

NHC forecasters noted that catastrophic and life-threatening flooding continues in southeastern Texas and portions of southwestern Louisiana. Harvey is expected to produce additional rainfall accumulations of 6 to 12 inches through Friday over parts of the upper Texas coast into southwestern Louisiana. 

Isolated storm totals may reach 50 inches over the upper Texas coast, including the Houston/Galveston metropolitan area.  These rains are currently producing catastrophic and life-threatening flooding over large portions of southeastern Texas and southwestern Louisiana.

Elsewhere, Harvey is expected to produce additional rainfall amounts of 5 to 10 inches across portions of southern Louisiana into coastal Mississippi and Alabama. Rainfall associated with Harvey will spread north by mid to late week, with rainfall amounts of 4 to 8 inches spreading into portions of Arkansas and the Tennessee Valley.

A list of rainfall observations compiled by the NOAA Weather Prediction Center can be found at: http://www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

Winds, Storm Surge, Ocean Swells

Tropical storm conditions are occurring over portions of the warning area along the coast and are likely to persist during the next day or so.

The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline.  The water is expected to reach the following heights above ground if the peak surge occurs at the time of high tide...

San Luis Pass to Morgan City including Galveston Bay...1 to 3 ft

The deepest water will occur along the immediate coast near the area of onshore winds.  Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.

Swells generated by Harvey are still affecting the coasts of Texas and Louisiana.  These swells are likely to cause life-threatening surf and rip current conditions.

Harvey's Location at 1 p.m. CDT, Aug. 29

At 1 p.m. CDT (1800 UTC), the center of Tropical Storm Harvey was located near 28.8 degrees north latitude and 94.3 degrees west longitude. That's about 80 miles (130 km) south-southwest of Port Arthur, Texas and about 95 miles (155 km) southwest of Cameron, Louisiana. Harvey was moving a little faster toward the north-northeast near 8 mph (13 kph), and this general motion is expected to continue today and tomorrow, Aug. 30. On the forecast track, the center of Harvey is expected to move inland over the northwestern Gulf within the tropical storm warning area later tonight or early Wednesday.

Maximum sustained winds remain near 45 mph (75 kph) with higher gusts. NHC said no significant change in strength is expected before the center moves inland. A gradual weakening should begin thereafter. The estimated minimum central pressure is 997 millibars.

(Update #2) Harvey's Rainfall and Structure Seen by GPM

The Global Precipitation Mission (GPM) Core Observatory captured these images of Hurricane Harvey at 7:45 a.m. EDT (11:45 UTC) and 5:25 p.m. EDT (21:25 UTC) on the August 27, 2017 nearly two days after the storm made landfall as it was meandering slowly southeast at just 2 mph (~4 kph) near Victoria, Texas west of Houston.

GPM Video of Harvey's Rainfall

Video Credits: NASA's Scientific Visualization Studio. GPM data provided by the joint NASA/JAXA GPM mission.

The animation shows rain rates derived from GPM's GMI microwave imager (outer swath) and dual-frequency precipitation radar or DPR (inner swath) overlaid on enhanced infrared data from the GOES-East satellite.

Harvey's cyclonic circulation is still quite evident in the infrared clouds, but GPM shows that the rainfall pattern is highly asymmetric with the bulk of the rain located north or east of the center. A broad area of moderate rain can be seen stretching from near Galveston Bay to north of Houston and back well to the west. Within this are embedded areas of heavy rain (red areas); the peak estimated rain rate from GPM during these overpasses was 96 mm/hr (~3.77 inches per hour). The animation was created at the NASA's Scientific Visualization Studio, at NASA's Goddard Space Flight Center, Greenbelt, Md.

With Harvey's circulation still reaching out over the Gulf of Mexico the storm is able to draw in a continuous supply of warm moist air to sustain the large amount of rain it is producing.

(Update #1)  NASA Watching Harvey from Satellites and the International Space Station

NASA has a lot of resources providing information on Tropical Storm Harvey as it continues to drop tremendous, flooding rainfall on Texas and Louisiana. Satellites like NASA's Aqua satellite and platforms like aircraft and the International Space Station continue to provide various kinds of data on the storm.

"NASA focuses on developing new research capabilities that can be used by our partners in the operational and response communities," said Dalia Kirschbaum, Research Physical Scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "While we continue to innovate in the type of information from satellites, models, and airborne platforms, the main focus is to ensure that the partners that are responding operationally to this event have the information in the format that they need to make effective decisions on emergency response. We continually and actively engage to ensure that the data pipeline is as effective and useful as possible."

NASA Resources in Action


Image above: Astronaut Randy Bresnik took this photo of Tropical Storm Harvey from the International Space Station on Aug. 28 at 1:27 p.m. CDT. Image Credit: NASA.

The International Space Station has provided a view of Harvey from its orbit in space. On Aug. 28 at 1:27 p.m. CDT Astronaut Randy Bresnik took a photo of Tropical Storm Harvey 

An infrared image taken at 2:29 p.m. CDT (19:29 UTC) on Aug. 28, 2017 from NASA's Atmospheric Infrared Sounder (AIRS) instrument aboard NASA's Aqua satellite illustrated the growing flood threat from Tropical Storm Harvey.  The data showed a large area of coldest cloud top temperatures and strongest thunderstorms centered along the southeastern Texas coast. A second area of intense precipitation was visible over southeastern Louisiana.


Image above: This false-colored infrared image acquired from the AIRS instrument aboard NASA's Aqua satellite at 2:29 p.m. CDT (19:29 UTC) on Aug. 28, shows a large area of coldest cloud top temperatures and strongest thunderstorms (dark blue and purple) centered along the southeastern Texas coast. A second area of intense precipitation is visible over southeastern Louisiana. Image Credits: NASA JPL/Ed Olsen.

Harvey has reemerged over the Gulf of Mexico, but the National Hurricane Center forecasts only a small amount of strengthening before the storm moves slowly north and inland again.

National Hurricane Center Warnings and Watches

On Aug. 29 at 7 a.m. CDT, the National Hurricane Center (NHC) warned "Catastrophic and life-threatening flooding continues and continued heavy rainfall today is expected to worsen the flood situation in southeastern Texas and southwestern Louisiana." A Tropical Storm Warning is in effect from Mesquite Bay, Texas to Intracoastal City, Louisiana. A Storm Surge Watch is in effect from Port Bolivar, Texas to Morgan City, Louisiana.

There are also many flood warnings in effect throughout southeastern Texas and southwestern Louisiana. For specific forecasts, visit: http://www.weather.gov/.

More Rainfall Expected Today, August 29, 2017

NHC forecasters said "Harvey is expected to produce additional rainfall accumulations of 7 to 13 inches through Friday over parts of the upper Texas coast into southwestern Louisiana.  Isolated storm totals may reach 50 inches over the upper Texas coast, including the Houston/Galveston metropolitan area. Elsewhere, Harvey is expected to produce total rain accumulations of 5 to 15 inches farther east across south-central Louisiana. Rainfall amounts of 5 to 10 inches are expected in southeast Louisiana and coastal Mississippi and Alabama."

Harvey's Location at 7 a.m. CDT, August 29, 2017

At 7 a.m. CDT (1200 UTC), the center of Tropical Storm Harvey was estimated near 28.2 degrees north and 94.6 degrees west longitude. Harvey's center of circulation was about 90 miles (145 km) east-southeast of Port O'Connor, Texas. Harvey is moving toward the east-northeast near 3 mph (6 kph), and this motion is expected to continue through this morning.

Maximum sustained winds remain near 45 mph (75 kph) with higher gusts. Little change in strength is forecast during the next 48 hours. Tropical-storm-force winds extend outward up to 175 miles (280 km) from the center. The estimated minimum central pressure is 997 millibars.

A turn toward the northeast is expected later today and tonight, followed by a turn toward the north-northeast on Wednesday, Aug. 30. On the forecast track, the center of Harvey is expected to be just offshore of the middle and upper coasts of Texas through tonight, then move inland over the northwestern Gulf coast on Wednesday, Aug. 30.

A list of rainfall observations compiled by the NOAA Weather Prediction Center can be found at: http://www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

For downloadable video, visit: https://svs.gsfc.nasa.gov/4458

GPM (Global Precipitation Measurement): http://www.nasa.gov/mission_pages/GPM/main/index.html and http://www.eorc.jaxa.jp/GPM/index_e.htm

For updated forecasts and warnings, visit: http://www.nhc.noaa.gov.

For local warnings and watches, visit: http://www.weather.gov/

Images (mentioned), Videos (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro/JPL/Alan Buis.

Greetings, Orbiter.ch