mardi 17 octobre 2017

Astronauts Prep for Spacewalk and Check Science Gear












ISS - Expedition 53 Mission patch.

October 17, 2017

International Space Station (ISS). Image Credit: NASA

Two NASA astronauts are getting ready to go on their mission’s third spacewalk on Friday. In the midst of those preparations, the Expedition 53 crew also worked on science gear exploring a wide variety of space phenomena.

Commander Randy Bresnik is preparing to go on the third spacewalk this month with NASA astronaut Joe Acaba. Astronauts Paolo Nespoli and Mark Vande Hei will assist the spacewalking duo in and out of their spacesuits on Friday.

The spacewalkers will replace a camera light on the Canadarm2’s newly-installed Latching End Effector and install a high-definition camera on the starboard truss. Other tasks include the replacement of a fuse on Dextre’s payload platform and the removal of thermal insulation on two electrical spare parts housed on stowage platforms.


Image above: Astronaut Mark Vande Hei is pictured tethered to the outside of the U.S. Destiny laboratory module during a spacewalk on Oct. 10, 2017. Image Credit: NASA.

Bresnik started his day working on a specialized camera that photograph’s meteors entering the Earth’s atmosphere. Acaba finally wrapped up the day configuring a microscope inside the Fluids Integrated Rack.

Nespoli, from the European Space Agency, set up the new Mini-Exercise Device-2 (MED-2) for a workout session today. Researchers are exploring the MED-2 for its ability to provide effective workouts while maximizing space aboard a spacecraft.

Related links:

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

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

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

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

Greetings, Orbiter.ch

Webcam on Mars Express surveys high-altitude clouds












ESA - Mars Express Mission patch.

17 October 2017

An unprecedented catalogue of more than 21 000 images taken by a webcam on ESA’s Mars Express is proving its worth as a science instrument, providing a global survey of unusual high-altitude cloud features on the Red Planet.

Cloud over Mars

The low-resolution camera was originally installed on Mars Express for visual confirmation that the Beagle-2 lander had separated in 2003. In 2007 it was switched back on and used primarily for outreach, education and citizen science, with images automatically posted to a dedicated Flickr page, sometimes within just 75 minutes of being taken at Mars.

Last year, with new software, the camera was adopted as a supporting science instrument. Now, the first paper has been published, on detached, high-altitude cloud features and dust storms over the edge, or ‘limb’, of the planet.

While these limb clouds can be imaged by other instruments or spacecraft, it is not necessarily their main task – they are usually looking directly at the surface with a narrow field of view that covers a small portion of the planet for specialised study. By contrast, the webcam often has a global view of the full limb.

“For this reason, limb observations in general are not so numerous, and this is why our images are so valuable in contributing to our understanding of atmospheric phenomena,” says Agustin Sánchez-Lavega, lead author of the study from the University del Pais Vasco in Bilbao, Spain.

“Combining with models and other datasets we were able to gain a better insight to understanding atmospheric transport and seasonal variations that play a role in generating the high-altitude cloud features.”

Cloud structures over Mars

The catalogue of some 21 000 images taken between 2007 and 2016 were examined and 300 identified for the study.

Multiple images separated by a few minutes each were obtained for 18 events as they rotated into view, providing visual documentation of the features from different perspectives.

In general, the cloud features imaged by the camera have peak altitudes in the range of 50–80 km above the planet and extend horizontally from about 400 km up to 1500 km.

In order to understand the nature of the clouds – for example, if they were primarily composed of dust or icy particles – the team compared the images with atmospheric property predictions detailed by the Mars Climate Database. The database uses temperature and pressure information to indicate if either water or carbon dioxide clouds could be capable of forming at that time and altitude.

Mars Express

The team also looked at the weather report generated from images by NASA’s Mars Reconnaissance Orbiter, and in some cases had additional corresponding observations obtained from other sensors on ESA’s Mars Express.

From the 18 studied in depth, most were concluded to be water-ice clouds, and one was attributed to a dust storm.

The high water-ice clouds seemed to depend on the position of the sun: they are present at sunrise and early afternoon, when temperatures are lower, allowing water-ice to condense. Later in the day, as the sunlight increases, the water-ice evaporates, and they dissipate.

Temperature variability and water vapour content according to the season, as well as atmospheric dynamics, can also play a role in the visible characteristics of the clouds.

Dust clouds over Mars

One event was attributed to a local dust storm in the northern hemisphere, which was also captured by images taken looking down on the surface by the Mars Reconnaissance Orbiter. The storm evolved rapidly, and took on arc shape with a front of about 1950 km on its outer edge and 730 km on its internal edge, and a width of 60–130 km. Limb observations by the webcam indicated the altitude was about 65 km.

“This long-term monitoring has allowed us to detect and measure the extent of dust and clouds over the limb of the planet, and study changes with a high cadence of imaging,” says Dmitri Titov, ESA’s Mars Express project scientist.

“We will continue to maintain the database with systematic observations from the webcam to provide wide views of atmospheric phenomena.”

Notes for editors:

“Limb clouds and dust on Mars from images obtained by the Visual Monitoring Camera (VMC) onboard Mars Express,” A. Sánchez-Lavega et al is published in Icarus 299 (2018): http://www.sciencedirect.com/science/article/pii/S0019103517301501?via%3Dihub

All webcam images are freely available via the dedicated Flickr account, here: https://www.flickr.com/photos/esa_marswebcam/

Mars Climate Database: http://www-mars.lmd.jussieu.fr/mars/access.html

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

Mars Express overview: http://www.esa.int/Our_Activities/Space_Science/Mars_Express_overview

Mars Express in-depth: http://sci.esa.int/marsexpress

ESA Planetary Science archive (PSA): http://www.rssd.esa.int/PSA

High Resolution Stereo Camera: http://berlinadmin.dlr.de/Missions/express/indexeng.shtml

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

Behind the lens... http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Behind_the_lens

Frequently asked questions: http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Frequently_asked_questions

Text, Images, Credits: ESA/Markus Bauer/Dmitri Titov/University del Pais Vasco/Agustin Sánchez-Lavega/MARCI: NASA/JPL/MSSS; VMC: ESA , CC BY-SA 3.0 IGO.

Best regards, Orbiter.ch

lundi 16 octobre 2017

Fresh Findings From Cassini












NASA & ESA - Cassini-Huygens Mission to Saturn & Titan patch.

Oct. 16, 2017


Image above: Saturn looms in the foreground of this mosaic of Cassini images, taken by the spacecraft on May 28, 2017. The planet is adorned by ring shadows. The icy rings emerge from behind the planet. Image Credits: NASA/JPL-Caltech/Space Science Institute.

NASA's Cassini spacecraft ended its journey on Sept. 15 with an intentional plunge into the atmosphere of Saturn, but analysis continues on the mountain of data the spacecraft sent during its long life. Some of the Cassini team's freshest insights were presented during a news conference today at the American Astronomical Society Division for Planetary Science meeting in Provo, Utah.

Among the findings being shared:

-- Views from Cassini's Grand Finale show the beauty of the rings and demonstrate processes similar to those that form planets.

During Cassini's final months, the spacecraft's cameras captured views from within the gap between the planet and the rings, and the mission is releasing two new image mosaics showing the rings from that unique perspective. One view, from May 28, 2017, shows the rings emerging from behind the planet's hazy limb, while the planet itself is adorned with ring shadows. The other mosaic shows a panoramic view outward across the ringscape.


Animation above: Cassini used its Ultraviolet Imaging Spectrograph to capture this final view of ultraviolet auroral emissions in Saturn's north polar region on Sept. 14, 2017. Animation Credits: NASA/JPL/Univ. Colorado/Univ. Liege-LPAP.

Researchers also shared a new movie of Saturn's auroras in ultraviolet light that represents the final such view from the spacecraft's Ultraviolet Imaging Spectrometer.

In addition, Cassini participating scientist and imaging team associate Matt Tiscareno of SETI Institute, Mountain View, California, provided new details about the whimsically named ring features called propellers, which are wakes in the rings created by small, unseen moonlets. The propellers are analogous to baby planets forming in disks around young stars, as they obey similar physical processes.

Tiscareno said that, in its last images of the rings (taken the day before the spacecraft's plunge into Saturn), Cassini successfully imaged all six of the propellers whose orbits were being tracked over the last several years of the mission. These objects are named for famous aviators: Blériot, Earhart, Santos-Dumont, Sikorsky, Post and Quimby. During its Ring-Grazing Orbits -- the four months of close orbits that preceeded the mission's Grand Finale -- Cassini obtained images showing swarms of smaller propellers, astounding Tiscareno and colleagues.

(Click on the image for enlarge)

Image above: Cassini obtained this panoramic view of Saturn's rings on Sept. 9, 2017, just minutes after it passed through the ring plane. Image Credits: NASA/JPL-Caltech/Space Science Institute.

-- Cassini's electronic "nose" hit the jackpot, finding many surprises as it sniffed the gases in the previously unexplored space between the planet and the rings.

The spacecraft's Ion and Neutral Mass Spectrometer (INMS) returned a host of first-ever direct measurements of the components in Saturn’s upper atmosphere, which stretches almost to the rings. From these observations, the team sees evidence that molecules from the rings are raining down onto the atmosphere. This influx of material from the rings was expected, but INMS data show hints of ingredients more complex than just water, which makes up the bulk of the rings' composition. In particular, the instrument detected methane, a volatile molecule that scientists would not expect to be abundant in the rings or found so high in Saturn’s atmosphere. Cassini participating scientist and INMS team associate Mark Perry from the Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, says the team is busy analyzing data from the final, lowest-altitude passes, which show even more complexity and variability. The INMS observations complement those by Cassini's Cosmic Dust Analyzer instrument, which sampled solid particles in the gap during the Grand Finale.

-- Researchers continue trying to wrangle insights about the length of the planet's day from measurements of Saturn's magnetic field.

Michele Dougherty, leader of Cassini's Magnetometer team from Imperial College London, provided an update on the team's progress in trying to determine whether Saturn's magnetic field has a detectable tilt. One aim of their work is to determine the precise length of time for the planet's internal rotation, which would help researchers nail down the true length of the planet's day. Dougherty says the sensitivity of Cassini's magnetic field measurements nearly quadrupled over the course of the spacecraft's 22 Grand Finale orbits -- meaning that, if the tilt of Saturn's field is greater than 0.016 degrees, researchers should be able to detect it. An extremely small tilt is challenging to explain with scientists' current understanding of how planetary magnetic fields are generated, thus suggesting more sophisticated dynamics inside Saturn.

-- New theoretical research explains the forces that keep Saturn's rings from spreading out and dispersing. It turns out to be a group effort.

Key among the questions scientists hope to answer using data from Cassini are the age and origins of the rings. Theoretical modeling has shown that, without forces to confine them, the rings would spread out over hundreds of millions of years -- much younger than Saturn itself. This spreading happens because faster-moving particles that orbit closer to Saturn occasionally collide with slower particles on slightly farther-out orbits. When this happens, some momentum from the faster particles is transferred to the slower particles, speeding the latter up in their orbit and causing them to move farther outward. The inverse happens to the faster, inner particles.

Previous research had shown that gravitational tugs from the moon Mimas are solely responsible for halting the outward spread of Saturn's B ring -- that ring's outer edge is defined by the dark region known as the Cassini Division. Ring scientists had thought the small moon Janus was responsible for confining the outer edge of the A ring. But a new modeling study led by Radwan Tajeddine of Cornell University, Ithaca, New York, shows that the A ring's outward creep is kept in check by a confederation of moons, including Pan, Atlas, Prometheus, Pandora, Janus, Epimetheus and Mimas.

Cassini Grand Finale. Animation Credits: NASA/JPL-Caltech/Space Science Institute

The insight was made possible by Cassini, which provided scientists with high-resolution views of intricate waves in the rings, along with precise determinations of the masses of Saturn's moons. Analysis of these data led Tajeddine and colleagues to an understanding that a cumulative effect of waves from all these moons damps the outward transfer of momentum in the A ring and confines its edge.

Tajeddine will present these results in a poster at the DPS meeting, and they will be published Wednesday in the Astrophysical Journal.

"There are whole careers to be forged in the analysis of data from Cassini," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory, Pasadena, California. "In a sense, the work has only just begun."

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.

More information about Cassini:

https://www.nasa.gov/cassini

https://saturn.jpl.nasa.gov

http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images (mentioned), Animations (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Preston Dyches.

Best regards, Orbiter.ch

NASA Sees Hurricane Ophelia Lashing Ireland














NASA & NOAA - Suomi NPP Mission logo / NASA & JAXA - Global Precipitation Measurement (GPM) patch.

Oct. 16, 2017

Ophelia (Atlantic Ocean)

NASA-NOAA's Suomi NPP satellite provided a thermal view of the clouds in hurricane Ophelia as it lashed Ireland. The Global Precipitation Measurement mission core satellite provided a look at the rainfall that was affecting the Emerald Isle.


Image above: NASA-NOAA's Suomi NPP satellite took this thermal image of Hurricane Ophelia over Ireland on Oct. 16 at 02:54 UTC (Oct. 15 at 10:54 p.m. EDT). Image Credits: NOAA/NASA Goddard Rapid Response Team.

The Global Precipitation Measurement mission or GPM core observatory passed directly above Hurricane Ophelia on October 14, 2017 at 12:56 p.m. EDT (1656 UTC) when it was a powerful category three on the Saffir-Simpson hurricane wind scale with sustained winds of close to 115 mph (100 knots).

GPM's Microwave Imager (GMI) and Dual-Frequency Precipitation Radar (DPR) instruments collected data showing the locations of extremely heavy rainfall with the hurricane. GPM's radar unveiled intense downpours in the northeastern side of Ophelia's eye wall that were dropping rain at the extreme rate of over 8.4 inches (213 mm) per hour. GPM saw rainfall in other intense feeder bands producing rain at a rate of over 3.9 mm (100 mm) per hour.


Image above: GPM core observatory passed directly above Hurricane Ophelia on Oct. 14 at 12:56 p.m. EDT (1656 UTC) GPM's radar unveiled intense downpours in the northeastern side of Ophelia's eye wall that were dropping rain at the extreme rate of over 8.4 inches (213 mm) per hour. GPM saw rainfall in other intense feeder bands producing rain at a rate of over 3.9 mm (100 mm) per hour. Image Credits: NASA/JAXA, Hal Pierce.

At NASA's Goddard Space Flight Center in Greenbelt, Maryland, a 3-D animation revealed the height of precipitation within hurricane Ophelia. The animation was produced by combining data from GPM's radar (DPR Ku band) with heights of cloud tops based on GOES-EAST satellite image temperatures.

The National Hurricane Center said that that the rainfall GPM observed would be affecting Ireland. Ophelia is expected to produce rainfall amounts of 2 to 3 inches (50 mm to 75 mm) with isolated totals near 4 inches (100 mm) through Tuesday across western Ireland and Scotland. Across eastern Ireland, rainfall amounts will average around 1 inch (25 mm) or less.

The 3-D animation showed storm tops in the northeastern side of Ophelia's eye wall (bright yellow) were shown by GPM's radar reaching heights of above 7.6 miles (12.4 km). The structure of hurricane Ophelia's eye wall is clearly shown with this close-up virtual flyby above the center of the tropical cyclone. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.

video
NASA Sees Powerful Storms and Heavy Rain in Hurricane Ophelia

Video above: This 3-D animation of data from the GPM core satellite on Oct. 15 showed storm tops in the northeastern side of Ophelia's eye wall (bright yellow) were shown by GPM's radar reaching heights of above 7.6 miles (12.4 km). The structure of hurricane Ophelia's eye wall is clearly shown with this close-up virtual flyby above the center of the tropical cyclone. Video Credits: NASA/JAXA, Hal Pierce.

On Sunday, Oct. 14 at 11 p.m. EDT/AST, the National Hurricane Center in Miami, Florida issued the final advisory on Post-Tropical Cyclone Ophelia. The storm had transitioned from a hurricane to a post- tropical cyclone and was centered about 220 miles (355 km) southwest of Mizen Head, Ireland near 49.2 degrees north latitude and 13.3 degrees west longitude.

The post-tropical cyclone is moving toward the north near 44 mph (70 kph). On the forecast track, the center of the post-tropical cyclone will move near western Ireland on Monday, Oct. 16 and then near northern Scotland Monday night.

Maximum sustained winds were near 85 mph (140 kph) with higher gusts.  Weakening is forecast during the next couple of days, and the post-tropical cyclone is expected to dissipate near western Norway by Tuesday night, Oct. 17. The estimated minimum central pressure was 969 millibars.

NASA-NOAA's Suomi NPP satellite measured temperatures of Ophelia's cloud tops as it passed overhead early on Oct. 16. The VIIRS instrument aboard captured a thermal image of Hurricane Ophelia over Ireland on Oct. 16 at 02:54 UTC (Oct. 15 at 10:54 p.m. EDT). Coldest cloud tops appeared northwest of the center, showing that the upper level of Ophelia was pushed from wind shear.

NHC forecaster Berg said "the last bit of deep convection near Ophelia's center has been sheared off well to the north, and the cyclone has acquired a definitive extratropical structure. Ophelia has completed its transition to an occluded low, with an attached warm front extending northeastward across Ireland and a cold front draped southeastward toward Spain and Portugal."

On Oct. 16, the U.K. Met Service Chief Forecaster Paul Gundersen said that Ophelia weakened on Sunday night and was no longer classified as a hurricane. However, the UK Met Service expects hurricane force winds of up to 80 mph across Northern Ireland, and some areas bordering the Irish Sea.

National Severe Weather Warnings are in place for Northern Ireland, and other western and northern parts of Britain for Oct, 16, Monday afternoon and evening. For updated forecasts and warnings, visit: http://www.metoffice.gov.uk/

Suomi NPP (National Polar-orbiting Partnership): http://www.nasa.gov/mission_pages/NPP/main/index.html

GPM (Global Precipitation Measurement): http://www.nasa.gov/mission_pages/GPM/main/index.html

Images (mentioned), Video (mentioned), Text, Credits: NASA's Goddard Space Flight Center, By Rob Gutro/Hal Pierce.

Greetings, Orbiter.ch

Hubble, Integral, Fermi, LIGO & Virgo Interferometer observes source of gravitational waves for the first time













 
ESA - Hubble Space Telescope logo / ESA - Integral Mission patch / NASA - Fermi Gamma-ray Telescope logo.

16 October 2017

Hubble observes first kilonova

The NASA/ESA Hubble Space Telescope has observed for the first time the source of a gravitational wave, created by the merger of two neutron stars. This merger created a kilonova — an object predicted by theory decades ago — that ejects heavy elements such as gold and platinum into space. This event also provides the strongest evidence yet that short duration gamma-ray bursts are caused by mergers of neutron stars. This discovery is the first glimpse of multi-messenger astronomy, bringing together both gravitational waves and electromagnetic radiation.

On 17 August 2017 the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo Interferometer both alerted astronomical observers all over the globe about the detection of a gravitational wave event named GW170817 [1]. About two seconds after the detection of the gravitational wave, ESA’s INTEGRAL telescope and NASA’s Fermi Gamma-ray Space Telescope observed a short gamma-ray burst in the same direction.

Artist’s impression of two neutron stars merging

In the night following the initial discovery, a fleet of telescopes started their hunt to locate the source of the event. Astronomers found it in the lenticular galaxy NGC 4993, about 130 million light-years away. A point of light was shining where nothing was visible before and this set off one of the largest multi-telescope observing campaigns ever — among these telescopes was the NASA/ESA Hubble Space Telescope [2].

Several different teams of scientists used Hubble over the two weeks following the gravitational wave event alert to observe NGC 4993. Using Hubble’s high-resolution imaging capabilities they managed to get the first observational proof for a kilonova, the visible counterpart of the merging of two extremely dense objects — most likely two neutron stars [3]. Such mergers were first suggested more than 30 years ago but this marks the first firm observation of such an event [4]. The distance to the merger makes the source both the closest gravitational wave event detected so far and also one of the closest gamma-ray burst sources ever seen.

NGC 4993 seen with Hubble

“Once I saw that there had been a trigger from LIGO and Virgo at the same time as a gamma-ray burst I was blown away,” recalls Andrew Levan of the University of Warwick, who led the Hubble team that obtained the first observations. “When I realised that it looked like neutron stars were involved, I was even more amazed. We’ve been waiting a long time for an opportunity like this!”

Hubble captured images of the galaxy in visible and infrared light, witnessing a new bright object within NGC 4993 that was brighter than a nova but fainter than a supernova. The images showed that the object faded noticeably over the six days of the Hubble observations. Using Hubble’s spectroscopic capabilities the teams also found indications of material being ejected by the kilonova as fast as one-fifth of the speed of light.

Wide-field view of NGC 4993 (ground-based view)

“It was surprising just how closely the behaviour of the kilonova matched the predictions,” said Nial Tanvir, professor at the University of Leicester and leader of another Hubble observing team. “It looked nothing like known supernovae, which this object could have been, and so confidence was soon very high that this was the real deal.”

Connecting kilonovae and short gamma-ray bursts to neutron star mergers has so far been difficult, but the multitude of detailed observations following the detection of the gravitational wave event GW170817 has now finally verified these connections.

The changing brightness and colour of the kilonova seen in NGC 4993

“The spectrum of the kilonova looked exactly like how theoretical physicists had predicted the outcome of the merger of two neutron stars would appear,” says Levan. “It ties this object to the gravitational wave source beyond all reasonable doubt.”

video
Neutron star merger animation ending with kilonova explosion

The infrared spectra taken with Hubble also showed several broad bumps and wiggles that signal the formation of some of the heaviest elements in nature. These observations may help solve another long-standing question in astronomy: the origin of heavy chemical elements, like gold and platinum [5]. In the merger of two neutron stars, the conditions appear just right for their production.

The implications of these observations are immense. As Tanvir explains: “This discovery has opened up a new approach to astronomical research, where we combine information from both electromagnetic light and from gravitational waves. We call this multi-messenger astronomy — but until now it has just been a dream!”

video
Zoom on NGC 4993

Levan concludes: “Now, astronomers won’t just look at the light from an object, as we’ve done for hundreds of years, but also listen to it. Gravitational waves provide us with complementary information from objects which are very hard to study using only electromagnetic waves. So pairing gravitational waves with electromagnetic radiation will help astronomers understand some of the most extreme events in the Universe.”

Notes:

[1] The ripples in spacetime known as gravitational waves are created by moving masses, but only the most intense waves, created by rapid speed changes of very massive objects, can be detected by the current generation of detectors. Gravitational waves detectable from Earth are generated by collisions of massive objects, such as when two black holes or neutron stars merge.

[2] Next to Hubble, ESO’s Very Large Telescope, ESO’s New Technology Telescope, ESO’s VLT Survey Telescope, the MPG/ESO 2.2-metre telescope, the Atacama Large Millimeter/submillimeter Array, the Visible and Infrared Survey Telescope for Astronomy, the Rapid Eye Mount (REM) telescope, the Swope Telescope, the LCO .4-meter telescope, the American DECcam, and the Pan-STAARS survey all helped to identify and observe the event and its after-effects over a wide range of wavelengths.

[3] A neutron star forms when the core of a massive star (above eight times the mass of the Sun) collapses. This process is so violent that it crushes protons and electrons together to form subatomic particles called neutrons. They are supported against further collapse only by neutron degeneracy pressure. This makes neutron stars the smallest and densest stars known.

[4] In 2013 astronomers published results on the evidence for a kilonova, associated with a short gamma-ray burst. The observations in 2013 were far less conclusive, and hence more controversial, than the new results.

[5] These observations pin down the formation of elements heavier than iron through nuclear reactions within high-density stellar objects, known as r-process nucleosynthesis, something which was only theorised before.

More information:

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

The extensive list of team members involved in the discovery and analysis of this discovery can be found here.

Links:

Hubblecast 103: Hubble observes source of gravitational waves for the first time: http://www.spacetelescope.org/videos/heic1717a/

FAQ: http://www.spacetelescope.org/static/archives/releases/pdf/heic1717-faq.pdf

LIGO press release: http://www.caltech.edu/news/ligo-and-virgo-make-first-detection-gravitational-waves-produced-colliding-neutron-stars-80082

ESO press release: https://www.eso.org/public/news/eso1733/

Hubblesite release: http://hubblesite.org/news_release/news/2017-41

LIGO: https://www.ligo.caltech.edu/

Virgo: http://www.virgo-gw.eu/

ESA Integral release: http://www.esa.int/Our_Activities/Space_Science/Integral_sees_blast_travelling_with_gravitational_waves

Paper 1: “The emergence of a lanthanide-rich kilonova following the merger of two neutron stars”, by N. R. Tanvir et al. in ApJL: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1717/heic1717a.pdf

Paper 2: “The environment of the binary neutron star merger GW170817”, by A. J. Levan et al. in ApJL: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1717/heic1717b.pdf

Paper 3: “Discovery of the X-ray counterpart to the gravitational wave event GW170817” by E. Troja et al. in Nature: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1717/heic1717c.pdf

Paper 4: “Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger” by M. M. Kalila: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1717/heic1717d.pdf

Paper 5: “The Distance to NGC 4993 — The host galaxy of the gravitational wave event GW17017”, by J. Hjorth et al. in ApJL: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1717/heic1717e.pdf

Related links:

ESO’s Very Large Telescope (VLT): http://www.eso.org/public/teles-instr/paranal-observatory/vlt/

Atacama Large Millimeter/submillimeter Array (ALMA): http://www.eso.org/public/teles-instr/alma/

MPG/ESO 2.2-metre telescope: https://www.eso.org/public/teles-instr/lasilla/mpg22/

Rapid Eye Mount (REM): http://www.eso.org/public/teles-instr/lasilla/rem/

Swope Telescope: http://obs.carnegiescience.edu/swope

LCO .4-meter telescope: https://lco.global/observatory/0.4m/

DECcam: http://www.ctio.noao.edu/noao/node/1033

Pan-STAARS: https://panstarrs.stsci.edu/

ESA’s INTEGRAL telescope: http://sci.esa.int/integral/

NASA’s Fermi Gamma-ray Space Telescope: https://fermi.gsfc.nasa.gov/

NASA/ESA Hubble Space Telescope: http://www.spacetelescope.org/

Laser Interferometer Gravitational-Wave Observatory (LIGO): https://www.ligo.caltech.edu/

Virgo Interferometer: https://www.ego-gw.it/public/about/whatIs.aspx

Images, Videos, Text, Credit: NASA, ESA, ESO, Tanvir et al.//L. Calçada/M. Kornmesser/Digitized Sky Survey 2. Acknowledgement: Davide De Martin/Music: Johan B. Monell (www.johanmonell.com)/NASA, ESA, and J. DePasquale, and G. Bacon (STScI); Acknowledgment: A. Mellinger; Digitized Sky Survey (DSS), STScI/AURA.

Best regards, Orbiter.ch

Russian Spacecraft Delivers Station Supplies











ROSCOSMOS - Russian Vehicles patch.

October 16, 2017


Image above: The Russian 68P cargo craft is pictured just meters away from docking to the International Space Station. Image Credit: NASA TV.

video
Russian Cargo Craft Completes Journey to International Space Station

Traveling about 252 miles over eastern China, the unpiloted Russian Progress 68 cargo ship docked at 7:04 a.m. EDT to the Pirs Docking Compartment of the International Space Station.


Image above: Oct. 16, 2017: International Space Station Configuration. Four spaceships are parked at the space station including the Progress 67 and 68 resupply ships and the Soyuz MS-05 and MS-06 crew ships. Image Credit: NASA.

For more information about the current crew and the International Space Station, visit: http://www.nasa.gov/station

Related links:

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

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

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

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

Best regards, Orbiter.ch

dimanche 15 octobre 2017

United Launch Alliance Successfully Launches NROL-52 Mission for the National Reconnaissance Office


















ULA - NROL-52 Mission poster.


Oct. 15, 2017

Atlas V NROL-52 Launch

A United Launch Alliance (ULA) Atlas V rocket carrying a payload for the National Reconnaissance Office lifted off from Space Launch Complex-41 on Oct. 15 at 3:28 a.m. EDT. Designated NROL-52, the mission is in support of national security.

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Atlas V NROL-52 Launch Highlights

“Today’s launch is a testament to the tireless dedication of the ULA team, demonstrating why ULA continues to serve as our nation’s most dependable and successful launch provider,” said Laura Maginnis, ULA vice president of Government Satellite Launch. “After recovering from Hurricane Irma that came through the area last month, and the last week’s weather challenges, the team found the right opportunity today to deliver this critical national asset to orbit.”

This mission was launched aboard an Atlas V Evolved Expendable Launch Vehicle (EELV) 421 configuration vehicle, which includes a 4-meter payload fairing (PLF) and two solid rocket boosters. The Atlas booster for this mission was powered by the RD AMROSS RD-180 engine, and the Centaur upper stage was powered by the Aerojet Rocketdyne RL10C-1 engine.

This is ULA’s 7th launch in 2017 and the 122nd successful launch since the company was formed in December 2006.

“I want to thank the entire ULA team and our mission partners at the NRO and U.S. Air Force who made this, our 26th NRO launch, successful,” said Maginnis.

Quasar 8, 9, 10, 11 (SDS-2 1, 2, 3, 4) satellite

The EELV program was established by the USAF to provide assured access to space for Department of Defense and other government payloads. The commercially developed EELV program supports the full range of government mission requirements, while delivering on schedule and providing significant cost savings over the legacy launch systems.

ULA's next launch is the Joint Polar Satellite System-1 for NASA and the National Oceanic Atmospheric Administration. The launch is scheduled for Nov. 10 at 1:47 a.m. PST from Space Launch Complex-2 at Vandenberg Air Force Base, California.

With more than a century of combined heritage, United Launch Alliance is the nation’s most experienced and reliable launch service provider. ULA has successfully delivered more than 120 satellites to orbit that aid meteorologists in tracking severe weather, unlock the mysteries of our solar system, provide critical capabilities for troops in the field and enable personal device-based GPS navigation.

For more information on ULA, visit the ULA website at: http://www.ulalaunch.com/

Images, Video, Text, Credits: United Launch Alliance (ULA)/Günter's Space Page/Orbiter.ch Aerospace.

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