vendredi 2 octobre 2015

Hurricane Joaquin May Be Experiencing Eyewall Replacement in NASA Imagery

NASA - EOS Aqua Mission logo / NASA - ISS-RapidScat Mission logo.

Oct. 2, 2015

Joaquin - Atlantic Ocean

The National Hurricane Center indicated on October 2 that powerful Hurricane Joaquin may be experiencing eyewall replacement. The eye was visible on NASA Aqua satellite imagery October 1, but obscured twelve hours later. In addition, NASA's RapidScat instrument helped determine what part of the storm had the strongest winds.

An Inside Look at Joaquin's Strongest Winds

Image above: On Sept. 30 at 7:40 p.m. EDT, RapidScat saw strongest sustained winds in Joaquin's north and northwestern quadrants, stronger than 36 meters per second (80 mph/129.6 kph). Image Credits: NASA/JPL, Doug Tyler.

ISS-RapidScat instrument in action. Animation Credit: NASA

On September 30 at about 7:40 p.m. EDT, the International Space Station passed over Hurricane Joaquin in the Bahamas. The RapidScat instrument which flies aboard ISS measures sustained winds over open ocean and saw the hurricane's strongest sustained winds in the north and northwestern quadrants, stronger than 36 meters per second (80 mph/129.6 kph).

Visible Imagery

Image above: NASA's Aqua satellite captured this visible image of Hurricane Joaquin over Bahamas on Oct. 1 at 17:55 UTC (1:55 p.m. EDT). Image Credits: NASA Goddard MODIS Rapid Response Team.

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite captured a visible image of Hurricane Joaquin over Bahamas on Oct. 1 at 17:55 UTC (1:55 p.m. EDT). In the image, the eye was still visible. However, twelve hours later, visible imagery from NOAA's GOES-East satellite showed an eye obscured by clouds which forecasters at NOAA said could indicate that the eyewall of the storm was undergoing a replacement.

NASA's Aqua satellite. Image Credits: NASA/GSFC

Eyewall Replacement

In powerful hurricanes, a new eye begins to develop around the old eye. The new eye gradually decreases in diameter and replaces the old eye. When that happens, the intensity of the hurricane usually decreases. Despite the fact that eyewall replacement can mean a weakening in a powerful hurricane, it can also spread the hurricane force winds out over a larger area.

National Hurricane Center (NHC) Forecaster Brennan noted in the 5 a.m. EDT NHC discussion on October 2,"The eye of Joaquin has not been apparent in recent infrared imagery. The last pass of the Hurricane Hunter aircraft through the center around 04Z [midnight] showed indications of a double wind maximum at flight level, which could indicate that an eyewall replacement cycle is underway. The last report from the aircraft indicated that the central pressure still around 935 millibars. The initial intensity remains 115 knots pending the arrival of the next aircraft before 12Z [8 a.m. EDT]. Some fluctuations in intensity are possible during the next 12 to 24 hours due to eyewall replacement."

Warnings and Watches

On October 2, a Hurricane Warning was in effect for the central Bahamas, northwestern Bahamas including the Abacos, Berry Islands, Eleuthera, Grand Bahama Island, and New Providence, and The Acklins, Crooked Island, and Mayaguana in the southeastern Bahamas. A Hurricane Watch was in effect for Bimini and Andros Island.

In addition, a Tropical Storm Warning was in effect for the remainder of the southeastern Bahamas including the Turks and Caicos Islands, Andros Island, Cuban provinces of Camaguey, Los Tunas, Holguin, and Guantanamo.

Latest Update on Joaquin from the National Hurricane Center

At 8 a.m. EDT (1200 UTC), the center of Hurricane Joaquin was located near latitude 23.4 North, longitude 74.8 West. Joaquin was drifting toward the northwest near 3 mph (6 kph). The NHC expects a faster northward motion to begin later today (Oct. 2), followed by a turn toward the northeast and an increase in forward speed tonight and Saturday. On the forecast track, the core of the strongest winds of Joaquin will continue moving over portions of the central and northwestern Bahamas today. Joaquin will begin to move away from the Bahamas tonight and Saturday.

Maximum sustained winds are near 130 mph (215 kph) with higher gusts. Joaquin is a dangerous category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some fluctuations in intensity are possible during the next 24 hours. Slow weakening is expected to begin on Saturday.

Hurricane force winds extend outward up to 50 miles (85 km) from the center and tropical storm force winds extend outward up to 205 miles (335 km). The minimum central pressure just reported by an Air Force Reserve Hurricane Hunter aircraft is 937 millibars.

For the latest forecasts, visit the NHC website:

The NHC noted that gradual weakening is forecast after October 3 as the cyclone encounters increasing southwesterly wind shear, but Joaquin is expected to remain a powerful hurricane for the next several days.

Related links:

NASA's Goddard Space Flight Center:

NASA's Aqua satellite:


Images (mentioned), Animation (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro.

Best regards,

Curiosity's Drill Hole and Location are Picture Perfect

NASA - Mars Science Laboratory (MSL) patch.

October 2, 2015

On Tuesday, Sept. 29, NASA's Curiosity Mars rover drilled its eighth hole on Mars, and its fifth since reaching Mount Sharp one year ago. The drilling of the hole 2.6-inches (65 millimeters) deep in a rock the team labeled "Big Sky" is part of a multi-day, multi-step sequence that will result in the analysis of the Martian rock's ingredients in the rover's two onboard laboratories - the Chemistry and Mineralogy X-Ray diffractometer (CheMin) and the Sample Analysis at Mars (SAM) instrument suite.

Mount Sharp Comes In Sharply

Image above: This composite image looking toward the higher regions of Mount Sharp was taken on September 9, 2015, by NASA's Curiosity rover. In the foreground -- about 2 miles (3 kilometers) from the rover -- is a long ridge teeming with hematite, an iron oxide. Image Credits: NASA/JPL-Caltech/MSSS.

"With Big Sky, we found the ordinary sandstone rock we were looking for," said Curiosity Project Scientist Ashwin Vasavada. "It also happens to be relatively near sandstone that looks as though it has been altered by fluids -- likely groundwater with other dissolved chemicals. We are hoping to drill that rock next, compare the results, and understand what changes have taken place."

The analyses of the Big Sky rock-powder samples by CheMin and SAM will occur over the next week. Meanwhile, the team will be turning the rover's attention and its wheels towards the second rock, where the sample analysis process will begin anew.

Postcard from Mars. Image Credits: NASA/JPL-Caltech/MSSS.

Curiosity is currently on the lower slopes of Mount Sharp in a region covered in sandstone called the Stimson Unit. Two weeks ago, still in the same general vicinity, Curiosity took a pair of long-range images toward higher regions of the mountain. In the foreground -- about 2 miles (3 kilometers) from the rover -- is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plain rich in clay minerals. And just beyond that are a multitude of rounded buttes, all high in sulfate minerals. The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago. The Curiosity team hopes to be able to explore these diverse areas in the months and years ahead. Farther back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now are heavily eroded by winds.

Curiosity selfie with holes. Image Credits: NASA/JPL-Caltech/MSSS

"The only thing more stunning than these images is the thought that Curiosity will be driving through those lower hills one day," Vasavada said. "We couldn't help but send a postcard back to all those following her journey."

NASA's Mars Science Laboratory Project is using Curiosity to assess ancient habitable environments and major changes in Martian environmental conditions. NASA's Jet Propulsion Laboratory, a division of Caltech, built the rover and manages the project for NASA's Science Mission Directorate in Washington.

For more information about Curiosity, visit , and You can follow the mission on Facebook at and on Twitter at

Images (mentioned), Text, Credits: NASA/JPL/DC Agle/Guy Webster.


Rosetta's First Peek at the Comet's Dark Side

ESA - Rosetta Mission patch.

October 2, 2015

Since its arrival at comet 67P/Churyumov-Gerasimenko, the European Space Agency's Rosetta spacecraft has been surveying the surface and the environment of this curiously shaped body. But for a long time, a portion of the nucleus -- the dark, cold regions around the comet's south pole -- remained inaccessible to almost all instruments on the spacecraft.

Due to a combination of its double-lobed shape and the inclination of its rotation axis, Rosetta's comet has a very peculiar seasonal pattern over its 6.5-year-long orbit. Seasons are distributed very unevenly between the two hemispheres. Each hemisphere comprise parts of both comet lobes and the "neck."

For most of the comet's orbit, the northern hemisphere experiences a very long summer, lasting over 5.5 years, while the southern hemisphere undergoes a long, dark and cold winter. However, a few months before the comet reaches perihelion -- the closest point to the sun along its orbit -- the situation changes, and the southern hemisphere transitions to a brief and very hot summer.

Image above: Image of the southern polar regions of comet 67P/Churyumov-Gerasimenkotaken was taken by Rosetta's Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) on September 29, 2014, when the comet was still xperiencing the long southern winter. Image Credits: ESA/Rosetta/MPS for OSIRIS Team.

When Rosetta arrived at 67P/C-G in August 2014, the comet was still experiencing its long summer in the northern hemisphere, and regions on the southern hemisphere received very little sunlight. Moreover, a large part of this hemisphere, close to the comet's south pole, was in polar night and had been in total darkness for almost five years.

With no direct illumination from the sun, these regions could not be imaged with Rosetta's OSIRIS (the Optical, Spectroscopic, and Infrared Remote Imaging System) science camera, or its Visible, InfraRed and Thermal Imaging Spectrometer (VIRTIS). For the first several months after Rosetta's arrival at the comet, only one instrument on the spacecraft could observe and characterize the cold southern pole of 67P/C-G: the Microwave Instrument for Rosetta Orbiter (MIRO).

In a paper accepted for publication in the journal Astronomy and Astrophysics, scientists report on the data collected by MIRO over these regions between August and October 2014.

"We observed the 'dark side' of the comet with MIRO on many occasions after Rosetta's arrival at 67P/C-G, and these unique data are telling us something very intriguing about the material just below its surface," said Mathieu Choukroun from NASA's Jet Propulsion Laboratory (JPL), Pasadena, California, lead author of the study.

Observing the comet's southern polar regions, Choukroun and colleagues found significant differences between the data collected with MIRO's millimeter and sub-millimeter wavelength channels. These differences might point to the presence of large amounts of ice within the first few tens of centimeters below the surface of these regions.

Images above: Subsurface temperature maps of 67P/Churyumov-Gerasimenko, showing the southern hemisphere of the comet.Images Credits: ESA/Rosetta/NASA/JPL-Caltech.

"Surprisingly, the thermal and electrical properties around the comet's south pole are quite different than what is found elsewhere on the nucleus," said Choukroun. "It appears that either the surface material or the material that's a few tens of centimeters below it is extremely transparent, and could consist mostly of water ice or carbon-dioxide ice."

The difference between the surface and subsurface composition of this part of the nucleus and that found elsewhere might originate in the comet's peculiar cycle of seasons. One of the possible explanations is that water and other gases that were released during the comet's previous perihelion, when the southern hemisphere was the most illuminated portion of the nucleus. The water condensed again and precipitated on the surface after the season changed and the southern hemisphere plunged again into its long and cold winter.

These are, however, preliminary results, because the analysis depends on the detailed shape of the nucleus. At the time the measurements were made, the shape of the dark, polar region was not known with great accuracy.

"We plan to revisit the MIRO data using an updated version of the shape model, to verify these early results and refine the interpretation of the measurements," added Choukroun.

Rosetta scientists will be testing these and other possible scenarios using data that were collected in the subsequent months, leading to the comet's perihelion, which took place on Aug. 13, 2015 and beyond.

In May 2015, the seasons changed on 67P/C-G and the brief, hot southern summer, which will last until early 2016, began. As the formerly dark southern polar regions started to receive more sunlight, it has been possible to observe them with other instruments on Rosetta, and the combination of all data might eventually disclose the origin of their curious composition.

"In the past few months, Rosetta has flown over the southern polar regions on several occasions, starting to collect data from this part of the comet after summer began there," said Matt Taylor, ESA Rosetta project scientist. "At the beginning of the southern summer, we had a paucity of observations in these regions as Rosetta's trajectory focused on the northern hemisphere due to ongoing communication with the lander, Philae. However, closer to perihelion we were able to begin observing the south."

Image above: Artist's impression of Rosetta orbiting its comet 67P/Churyumov-Gerasimenko. Image Credit: ESA/Rosetta/MPS for OSIRIS Team.

Rosetta is currently on an excursion out to about 930 miles (1,500 kilometers) from the nucleus to study the comet's environment at large. But the spacecraft will soon come closer to the comet, focusing on full orbits to compare the northern and southern hemispheres, as well as some slower passes in the south to maximize observations there. In addition, as activity will start to wane later this year, the team hopes to get closer to the nucleus and gain higher-resolution observations of the surface.

"First, we observed these dark regions with MIRO, the only instrument able to do so at the time, and we tried to interpret these unique data. Now, as these regions became warmer and brighter around perihelion, we can observe them with other instruments, too."

Mark Hofstadter, MIRO principal investigator at JPL, adds, "We hope that, by combining data from all these instruments, we will be able to confirm whether or not the south pole had a different composition and whether or not it is changing seasonally."

The MIRO instrument is a small, lightweight spectrometer that can map the abundance, temperature and velocity of cometary water vapor and other molecules that the nucleus releases. It can also measure the temperature up to about one inch (three centimeters) below the surface of the comet's nucleus. One reason the subsurface temperature is important is that the observed gases likely come from sublimating ices beneath the surface. By combining information on the gas and the subsurface, MIRO is able to study this process in detail.

Comets are time capsules containing primitive material left over from the epoch when the sun and its planets formed. Rosetta is the first spacecraft to witness at close proximity how a comet changes as it is subjected to the increasing intensity of the sun's radiation. Observations will help scientists learn more about the origin and evolution of our solar system and the role comets may have played in the formation of planets.

Rosetta is an ESA mission with contributions from its member states and NASA. Rosetta's Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; French National Space Agency, Paris; and the Italian Space Agency, Rome. JPL, Pasadena, California, a division of the California Institute of Technology in Pasadena, manages the U.S. contribution of the Rosetta mission for NASA's Science Mission Directorate in Washington. JPL also built the MIRO and hosts its principal investigator, Mark Hofstadter. The Southwest Research Institute (San Antonio and Boulder, Colorado), developed the Rosetta orbiter's IES and Alice instruments and hosts their principal investigators, James Burch (IES) and Alan Stern (Alice).

For more information on the U.S. instruments aboard Rosetta, visit:

More information about Rosetta is available at:

Images (mentioned), Text, Credits: NASA/Dwayne Brown/Laurie Cantillo/JPL/DC Agle/European Space Agency/Markus Bauer.

Best regards,

jeudi 1 octobre 2015

Space Station Receives Express Delivery in Six Hours

ROSCOSMOS - Russian Vehicles patch.

Oct. 1, 2015

Image above: A high-definition camera on the International Space Station spots the Progress 61 resupply vehicle (upper left) just minutes before it docked to the Zvezda service module. Image Credit: NASA TV.

Traveling about 252 miles over the North Atlantic, the unpiloted ISS Progress 61 Russian cargo spacecraft docked to the rear port of the Zvezda Service Module on the International Space Station at 6:52 p.m. EDT.

Russian Cargo Ship Arrives at the International Space Station

The spacecraft is delivering more than three tons of food, fuel and supplies, including 1,940 pounds of propellant, 110 pounds of oxygen, 926 pounds of water, and 3,397 pounds of spare parts and experiment hardware (2.3 tonnes of cargo) for the members of the Expedition 45 crew currently living and working in space.

Progress 61 is scheduled to remain docked to ISS for the next two months.

ROSCOSMOS Press Release:

For more information about the current crew and the International Space Station, visit:

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


Satellites Show Joaquin Become a Category 4 Hurricane

NOAA & NASA - GOES East Mission logo / NASA - Suomi-NPP Mission logo.

Oct. 1, 2015

Joaquin - Atlantic Ocean

Hurricane Joaquin had become a Category 4 hurricane on the Saffir-Simpson Wind Scale by 2 p.m. EDT on Oct. 1. At NASA, satellite imagery from NOAA's GOES-East satellite was compiled into an animation that showed the hurricane strengthening. Earlier in the day, NASA-NOAA's Suomi NPP satellite saw powerful thunderstorms within, indicating further strengthening.

Satellite Movie Shows Hurricane Joaquin in the Bahamas

Animation above: This animation of images captured from September 29 to October 1 from NOAA's GOES-East satellite shows Hurricane Joaquin become a major hurricane in the Bahamas. TRT: 00:32. Animation Credits: NASA/NOAA GOES Project.

The GOES-East satellite is managed by NOAA, and at NASA's GOES Project at the NASA Goddard Space Flight Center in Greenbelt, Maryland, imagery from GOES-East we compiled into an animation. The infrared and visible imagery from Sept. 29 to Oct. 1 from showed Hurricane Joaquin become a major hurricane in the Bahamas.

Earlier in the morning, NASA-NOAA's Suomi NPP satellite passed over Joaquin at 06:10 UTC (2:10 a.m. EDT) as it was strengthening from a Category 2 to a Category 3 hurricane. The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard captured an infrared image that showed cloud top temperatures colder than -63F/-53C, indicative of powerful storms within the hurricane. NASA research has shown that storms with cloud tops that high (and that stretch that high into the troposphere) have the capability to generate heavy rain.

NASA-NOAA GOES-East satellite

On Oct. 1, a Hurricane Warning was in effect for the Central Bahamas, Northwestern Bahamas including the Abacos, Berry Islands, Eleuthera, Grand Bahama Island, and New Providence, The Acklins, Crooked Island, and Mayaguana in the southeastern Bahamas. A Hurricane Watch was in effect for Bimini and Andros Island, and a Tropical Storm Warning was in effect for the remainder of the southeastern Bahamas excluding the Turks and Caicos Islands and Andros Island.

Image above: NASA-NOAA's Suomi NPP satellite passed over Joaquin at 06:10 UTC (2:10 a.m. EDT) on Oct. 1 as it was strengthening from a Category 2 to a Category 3 hurricane. Imagery showed cloud top temperatures colder than -63F/-53C (yellow). Image Credits: NRL/NASA/NOAA.

At 2 p.m. EDT (1800 UTC), the center of Hurricane Joaquin was located near latitude 23.0 North, longitude 74.2 West.  Joaquin was moving generally southwestward at about 6 mph (9 kph), and the National Hurricane Center forecast a turn toward the northwest and north on Friday, Oct. 2. On the forecast track, the center of Joaquin will move near or over portions of the central Bahamas today and tonight and pass near or over portions of the northwestern Bahamas on Friday, Oct. 2.

Reports from an Air Force Reserve Hurricane Hunter aircraft indicated that maximum sustained winds have increased to near 130 mph (210 kph) with higher gusts.  Joaquin is now a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.  Some additional strengthening is possible during the next 24 hours, with some fluctuations in intensity possible Friday night and Saturday.

NASA-NOAA Suomi NPP satellite

Hurricane force winds extend outward up to 45 miles (75 km) from the center and tropical storm force winds extend outward up to 140 miles (220 km).

The latest minimum central pressure extrapolated from Hurricane Hunter aircraft data is 936 millibars. For effects on the Bahamas, updates to forecasts, watches and warnings, visit the National Hurricane Center website:

The NHC updated forecast takes Joaquin on a more northerly track from Saturday, Oct. 3 through Tuesday, October 6 toward Long Island, New York. Tracks and forecasts are subject to change.

Related links:

NOAA's GOES-East satellite:

NASA-NOAA's Suomi NPP satellite:

Images, Animation (mentioned), Text, Credits: NASA's Goddard Space Flight Center/NOAA/Rob Gutro.


Progress M29-M Launch from Baikonur Cosmodrome to the ISS

ROSCOSMOS - Russian Vehicles patch.

Oct. 1, 2015

Progress M29-M Launch from Baikonur Cosmodrome

The Progress M-29M cargo spacecraft is en-route to the International Space Station, heading into orbit atop a Russian Soyuz U rocket on Thursday.

Progress 61P/M29-M Launch from Baikonur Cosmodrome to the ISS

Blasting off from the Baikonur Cosmodrome at 16:49 UTC, Soyuz lit up the night skies as it began chasing the Space Station that had passed over the launch site just minutes before.

Progress separation

Sticking to the express mission profile, the Progress will conduct four orbit-raising maneuvers in the first three hours of the mission followed by the initiation of the fully automated rendezvous sequence that will bring the Progress to the direct vicinity of ISS for a flyaround to set up for docking to the Zvezda module at 22:54 UTC to mark the on-time delivery of 2,369 Kilograms of cargo.

 Progress MS cargo cutaway

Today’s launch will be the last one for the Progress M-M series, to be replaced by the Progress MS cargo ships with the next mission due on November 21. The Progress cargo ship will be packed with 2.3 tonnes of cargo: fuel, air, equipment and also other supplies for the cosmonauts and astronauts, including over 17 kilograms of fruits and vegetables, ketchup, juice, sauce, chocolate sweets, jam and peanuts.

ROSCOSMOS Press Release:

Images, Video, Text, Credits: ROSCOSMOS/NASA TV/G. De Chara, Mars Center/Catherine Laplace-Builhe.


Pluto’s Big Moon Charon Reveals a Colorful and Violent History

NASA - New Horizons Mission logo.

Oct. 1, 2015

NASA’s New Horizons spacecraft has returned the best color and the highest resolution images yet of Pluto’s largest moon, Charon – and these pictures show a surprisingly complex and violent history. 

Image above: Charon in Enhanced Color NASA's New Horizons captured this high-resolution enhanced color view of Charon just before closest approach on July 14, 2015. The image combines blue, red and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera (MVIC); the colors are processed to best highlight the variation of surface properties across Charon. Charon’s color palette is not as diverse as Pluto’s; most striking is the reddish north (top) polar region, informally named Mordor Macula. Charon is 754 miles (1,214 kilometers) across; this image resolves details as small as 1.8 miles (2.9 kilometers). Image Credits: NASA/JHUAPL/SwRI.

At half the diameter of Pluto, Charon is the largest satellite relative to its planet in the solar system. Many New Horizons scientists expected Charon to be a monotonous, crater-battered world; instead, they’re finding a landscape covered with mountains, canyons, landslides, surface-color variations and more.

“We thought the probability of seeing such interesting features on this satellite of a world at the far edge of our solar system was low,” said Ross Beyer, an affiliate of the New Horizons Geology, Geophysics and Imaging (GGI) team from the SETI Institute and NASA Ames Research Center in Mountain View, California, “but I couldn't be more delighted with what we see."

Image above: High-resolution images of Charon were taken by the Long Range Reconnaissance Imager on NASA’s New Horizons spacecraft, shortly before closest approach on July 14, 2015, and overlaid with enhanced color from the Ralph/Multispectral Visual Imaging Camera (MVIC). Charon’s cratered uplands at the top are broken by series of canyons, and replaced on the bottom by the rolling plains of the informally named Vulcan Planum. The scene covers Charon’s width of 754 miles (1,214 kilometers) and resolves details as small as 0.5 miles (0.8 kilometers). Image Credits: NASA/JHUAPL/SwRI.

High-resolution images of the Pluto-facing hemisphere of Charon, taken by New Horizons as the spacecraft sped through the Pluto system on July 14 and transmitted to Earth on Sept. 21, reveal details of a belt of fractures and canyons just north of the moon’s equator.  This great canyon system stretches more than 1,000 miles (1,600 kilometers) across the entire face of Charon and likely around onto Charon’s far side. Four times as long as the Grand Canyon, and twice as deep in places, these faults and canyons indicate a titanic geological upheaval in Charon’s past.

“It looks like the entire crust of Charon has been split open,” said John Spencer, deputy lead for GGI at the Southwest Research Institute in Boulder, Colorado. “With respect to its size relative to Charon, this feature is much like the vast Valles Marineris canyon system on Mars.”

Image above: This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by NASA’s New Horizons spacecraft as it passed through the Pluto system on July 14, 2015. This image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically to allow direct comparison of their surface properties, and to highlight the similarity between Charon’s polar red terrain and Pluto’s equatorial red terrain. Pluto and Charon are shown with approximately correct relative sizes, but their true separation is not to scale. The image combines blue, red and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera (MVIC). Image Credits: NASA/JHUAPL/SwRI.

The team has also discovered that the plains south of the Charon’s canyon -- informally referred to as Vulcan Planum -- have fewer large craters than the regions to the north, indicating that they are noticeably younger. The smoothness of the plains, as well as their grooves and faint ridges, are clear signs of wide-scale resurfacing.

One possibility for the smooth surface is a kind of cold volcanic activity, called cryovolcanism. “The team is discussing the possibility that an internal water ocean could have frozen long ago, and the resulting volume change could have led to Charon cracking open, allowing water-based lavas to reach the surface at that time,” said Paul Schenk, a New Horizons team member from the Lunar and Planetary Institute in Houston. 

Flying Over Charon

Video above: Images from NASA's New Horizons spacecraft were used to create this flyover video of Pluto's largest moon, Charon. The “flight” starts with the informally named Mordor (dark) region near Charon’s north pole. The camera then moves south to a vast chasm, descending from 1,100 miles (1,800 kilometers) to just 40 miles (60 kilometers) above the surface to fly through the canyon system. From there it’s a turn to the south to view the plains and "moat mountain," informally named Kubrick Mons, a prominent peak surrounded by a topographic depression. New Horizons Long-Range Reconnaissance Imager (LORRI) photographs showing details at up to 400 meters per pixel were used to create the basemap for this animation. Those images, along with pictures taken from a slightly different vantage point by the spacecraft’s Ralph/ Multispectral Visible Imaging Camera (MVIC), were used to create a preliminary digital terrain (elevation) model. The images and model were combined and super-sampled to create this animation. Video Credits: NASA/JHUAPL/SwRI/Stuart Robbins.

Even higher-resolution Charon images and composition data are still to come as New Horizons transmits data, stored on its digital recorders, over the next year – and as that happens, “I predict Charon’s story will become even more amazing!” said mission Project Scientist Hal Weaver, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

The New Horizons spacecraft is currently 3.1 billion miles (5 billion kilometers) from Earth, with all systems healthy and operating normally.

New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama.  APL designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.

For more information and images, visit and

Images (mentioned), Video (mentioned), Text, Credits: NASA/Tricia Talbert.


mercredi 30 septembre 2015

Flight VA226 success: with Sky Muster and ARSAT-2 in orbit

Arianespace - Flight VA226 Mission poster.

September 30, 2015

Flight VA226 success: with Sky Muster and ARSAT-2 in orbit, Arianespace serves Australia and Argentina

Arianespace successfully launched two satellites this evening: Sky Muster for the Australian operator nbn (National Broadband Network) and ARSAT-2 for the Argentine operator ARSAT.

Image above: The Ariane 5 ascends from the Spaceport in French Guiana with a dual-satellite payload of Sky Muster and ARSAT-2.

Today's launch was the ninth of the year in nine months, a record for the Arianespace launcher family, and the fifth of the year and 68th successful launch in a row for the Ariane 5 heavy launcher. It lifted off at 5:30 p.m. local time from the Guiana Space Center (CSG) in Kourou, French Guiana.

Arianespace is proud of its role in providing sustained support for these two new regional operators, based in two great southern hemisphere nations, whose primary goal is to deliver the benefits of space to all of their citizens.

Flight VA226 success!

Arianespace and nbn team up to reduce the digital divide in Australia

Arianespace is especially proud of being chosen to launch the Australian operator nbn's first satellite.

Sky Muster will help reduce the digital divide on this nation-continent, by guaranteeing high-speed Internet access to more than 200,000 Australians living in rural and isolated areas of the country. It will cover the entire country, including Norfolk, Christmas, Macquarie and Cocos islands.

 Sky Muster satellite

Sky Muster is the 52nd geostationary platform built by SSL (and predecessors) to be orbited by Arianespace, which has 13 more satellites from this manufacturer in its launch manifest.

Arianespace and ARSAT: a fruitful partnership to consolidate and develop Argentina's satellite communications infrastructure

ARSAT-2 is the second satellite for the state-owned telecommunications company, ARSAT, and will enable Argentina to further develop and consolidate its own space telecom system. ARSAT-2 will cover the Americas, providing direct-to-home (DTH) TV transmissions, Internet access via VSAT antennas, data transmission and IP telephony services.

ARSAT-2 is the second geostationary satellite to be built and operated by Argentina. The company INVAP was in charge of its design and integration, as well as the production of certain components.

ARSAT-2 satellite

Using space to improve life on Earth

With the launch of these two strategic satellites for two great nations from the southern hemisphere, Australia and Argentina, Arianespace confirms its goal of providing its customers with the best possible transport solutions to help space-based systems improve life on Earth.

Shortly after the announcement that the two satellites had been injected into orbit, Arianespace Chairman and CEO Stéphane Israël said: "We are especially proud of our mission success this evening for two regional operators in the southern hemisphere, nbn and ARSAT, and we have already established real partnerships with both customers. With 400 satellites launched since its beginning, the Ariane family can celebrate a real ‘Triple A’ achievement this evening for Australia, Argentina and Arianespace. Thanks go to our clients for their confidence, and bravo to SSL and INVAP for their contributions to this success.

"This evening also marks the ninth launch in nine months for our family of launchers, in line with our goal of carrying out 12 launches in 2015. I would like to thank all our partners who have contributed to this 68th consecutive successful launch of Ariane 5: ESA, responsible for the Ariane program; all European companies who contribute to Ariane under the direction of industrial prime contractor Airbus Safran Launchers; CNES-CSG and companies at the launch base; and of course the men and women of Arianespace, who continue to demonstrate their commitment and professionalism." 

Wrapping up a record 2015

Following today’s success, Arianespace’s mission pace will continue with its next two flights from the Spaceport, both of which are to be performed during November: a heavy-lift Ariane 5 launch with the Arabsat-6B and GSAT-15 payloads (Flight VA227); and a mission with the light-lift Vega carrying Europe’s LISA Pathfinder (Flight VV06).

Related links:

nbn website:

SSL website:

ARSAT website:

INVAP website:

For more information about Arianespace, visit:

Images, Video, Text, Credits: Arianespace/Arianespace TV/ARSAT/SSL.

Best regards,

Dawn Team Shares New Maps and Insights about Ceres

NASA - Dawn Mission patch.

Sept. 30, 2015

Mysteries and insights about Ceres are being discussed this week at the European Planetary Science Conference in Nantes, France. NASA's Dawn spacecraft is providing scientists with tantalizing views and other data about the intriguing dwarf planet that they continue to analyze.

"Ceres continues to amaze, yet puzzle us, as we examine our multitude of images, spectra and now energetic particle bursts," said Chris Russell, Dawn principal investigator at the University of California, Los Angeles.

Image above: This map-projected view of Ceres was created from images taken by NASA's Dawn spacecraft during its high-altitude mapping orbit, in August and September, 2015. Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

A new color-coded topographic map shows more than a dozen recently approved names for features on Ceres, all eponymous for agricultural spirits, deities and festivals from cultures around the world. These include Jaja, after the Abkhazian harvest goddess, and Ernutet, after the cobra-headed Egyptian harvest goddess. A 12-mile (20-kilometer) diameter mountain near Ceres' north pole is now called Ysolo Mons, for an Albanian festival that marks the first day of the eggplant harvest.

Another new Ceres map, in false color, enhances compositional differences present on the surface. The variations are more subtle than on Vesta, Dawn's previous port of call. Color-coded topographic images of Occator (oh-KAH-tor) crater, home of Ceres' brightest spots, and a puzzling, cone-shaped 4-mile-high (6-kilometer-high) mountain, are also available. Scientists are still trying to identify processes that could produce these and other unique Cerean phenomena.

Image above: This view, made using images taken by NASA's Dawn spacecraft, features a tall conical mountain on Ceres. Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI.

"The irregular shapes of craters on Ceres are especially interesting, resembling craters we see on Saturn's icy moon Rhea," said Carol Raymond, Dawn's deputy principal investigator based at NASA's Jet Propulsion Laboratory, Pasadena, California. "They are very different from the bowl-shaped craters on Vesta."

A surprising bonus observation came from Dawn's gamma ray and neutron spectrometer. The instrument detected three bursts of energetic electrons that may result from the interaction between Ceres and radiation from the sun. The observation isn't yet fully understood, but may be important in forming a complete picture of Ceres.

Image above: This view, made using images taken by NASA's Dawn spacecraft, is a color-coded topographic map of Occator crater on Ceres. Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

"This is a very unexpected observation for which we are now testing hypotheses," Russell said.

Dawn is currently orbiting Ceres at an altitude of 915 miles (1,470 kilometers), and the spacecraft will image the entire surface of the dwarf planet up to six times in this phase of the mission. Each imaging cycle takes 11 days.

Starting in October and continuing into December, Dawn will descend to its lowest and final orbit, an altitude of 230 miles (375 kilometers). The spacecraft will continue imaging Ceres and taking other data at higher resolutions than ever before at this last orbit. It will remain operational at least through mid-2016.

Image above: This color-coded map from NASA's Dawn mission shows the highs and lows of topography on the surface of dwarf planet Ceres. It is labeled with names of features approved by the International Astronomical Union. Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Dawn made history as the first mission to reach a dwarf planet, and the first to orbit two distinct extraterrestrial targets, when it arrived at Ceres on March 6, 2015. It conducted extensive observations of Vesta in 2011 and 2012.

Dawn's mission is managed by JPL for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. For a complete list of mission participants, visit:

More information about Dawn is available at the following sites:

Images (mentioned), Text, Credits: NASA/JPL/Elizabeth Landau/Tony Greicius.

Best regards,

A Fresh Perspective on an Extraordinary Cluster of Galaxies

NASA - Chandra X-ray Observatory patch.

Sept. 30, 2015

Galaxy clusters are often described by superlatives. After all, they are huge conglomerations of galaxies, hot gas, and dark matter and represent the largest structures in the Universe held together by gravity.

Galaxy clusters tend to be poor at producing new stars in their centers. They generally have one giant galaxy in their middle that forms stars at a rate significantly slower than most galaxies – including our Milky Way. The central galaxy contains a supermassive black hole roughly a thousand times more massive than the one at the center of our galaxy. Without heating by outbursts from this black hole, the copious amounts of hot gas found in the central galaxy should cool, allowing stars to form at a high clip. It is thought that the central black hole acts as a thermostat, preventing rapid cooling of surrounding hot gas and impeding star formation.

New data provide more details on how the galaxy cluster SPT-CLJ2344-4243, nicknamed the Phoenix Cluster for the constellation in which it is found, challenges this trend. The cluster has shattered multiple records in the past: In 2012, scientists announced that the Phoenix cluster featured the highest rate of cooling hot gas and star formation ever seen in the center of a galaxy cluster, and is the most powerful producer of X-rays of all known clusters. The rate at which hot gas is cooling in the center of the cluster is also the largest ever observed.

New observations of this galaxy cluster at X-ray, ultraviolet, and optical wavelengths by NASA’s Chandra X-ray Observatory, the Hubble Space Telescope, and the Clay-Magellan telescope located in Chile, are helping astronomers better understand this remarkable object. Clay-Magellan’s optical data reveal narrow filaments from the center of the cluster where stars are forming. These massive cosmic threads of gas and dust, most of which had never been detected before, extend for 160,000 to 330,000 lights years. This is longer than the entire breadth of the Milky Way galaxy, making them the most extensive filaments ever seen in a galaxy cluster.

These filaments surround large cavities – regions with greatly reduced X-ray emission – in the hot gas. The X-ray cavities can be seen in this composite image that shows the Chandra X-ray data in blue and optical data from the Hubble Space Telescope (red, green, and blue). For the location of these “inner cavities”, mouse over the image. Astronomers think that the X-ray cavities were carved out of the surrounding gas by powerful jets of high-energy particles emanating from near a supermassive black hole in the central galaxy of the cluster. As matter swirls toward a black hole, an enormous amount of gravitational energy is released. Combined radio and X-ray observations of supermassive black holes in other galaxy clusters have shown that a significant fraction of this energy is released as jets of outbursts that can last millions of years. The observed size of the X-ray cavities indicates that the outburst that produced the cavities in SPT-CLJ2344-4243  SPT- CLJ2344-4243 was one of the most energetic such events ever recorded.

However, the central black hole in the Phoenix cluster is suffering from somewhat of an identity crisis, sharing properties with both “quasars”, very bright objects powered by material falling onto a supermassive black hole, and “radio galaxies” containing jets of energetic particles that glow in radio waves, and are also powered by giant black holes. Half of the energy output from this black hole comes via jets mechanically pushing on the surrounding gas (radio-mode), and the other half from optical, UV and X-radiation originating in an accretion disk (quasar-mode). Astronomers suggest that the black hole may be in the process of flipping between these two states. 

X-ray cavities located farther away from the center of the cluster, labeled as “outer cavities”, provide evidence for strong outbursts from the central black hole about a hundred million years ago (neglecting the light travel time to the cluster). This implies that the black hole may have been in a radio mode, with outbursts, about a hundred million years ago, then changed into a quasar mode, and then changed back into a radio mode.

Chandra X-ray Observatory

It is thought that rapid cooling may have occurred in between these outbursts, triggering star formation in clumps and filaments throughout the central galaxy at a rate of about 610 solar masses per year. By comparison, only a couple of new stars form every year in our Milky Way galaxy. The extreme properties of the Phoenix cluster system are providing new insights into various astrophysical problems, including the formation of stars, the growth of galaxies and black holes, and the co-evolution of black holes and their environment.

A paper describing these results, led by Michael McDonald (Massachusetts Institute of Technology), has been accepted for publication in The Astrophysical Journal and is available online ( NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

Read More from NASA's Chandra X-ray Observatory:

For more Chandra images, multimedia and related materials, visit:

Images, Text, Credits: NASA, X-ray: NASA/CXC/MIT/M. McDonald et al.; Optical: NASA/STScI.


Successful re-entry of H-II Transfer Vehicle “KOUNOTORI5” (HTV5)

JAXA - H-II Transfer Vehicle “KOUNOTORI 5” (HTV5) patch.

September 30, 2015

Space Station Crew Bids Sayonara to Japanese Cargo Ship (29 sept. 2015)

The H-II Transfer Vehicle “KOUNOTORI5” (HTV5) successfully re-entered the atmosphere after the third de-orbit maneuver at 5:08 a.m. on September 30, 2015 (Japanese Standard Time, JST).

The “KOUNOTORI5” has successfully accomplished its main objective of shipping cargo to the International Space Station (ISS), and completed its 42-day mission.

H-II Transfer Vehicle “KOUNOTORI 5” (HTV5)

The estimated date/time for the re-entry and waterlanding are as follows (Japanese Standard Time):

- Estimated re-entry*: September 30, 2015 / 5:33 a.m.
- Estimated waterlanding: September 30, 2015 / 5:47 a.m. - 6:13 a.m.

* Altitude at 120 km

Reference link: For more information, please refer to the following website:

HTV re-entry

Comment by JAXA President Completion of the H-II Transfer Vehicle “KOUNOTORI5”(HTV5) mission

Today, we would like to announce that the H-II Transfer Vehicle “Kounotori5” (HTV5) has successfully re-entered the Earth after completing a de-orbit maneuver. The KOUNOTORI5 berthed at the International Space Station (ISS) on August 25, 2015, and remained docked for approximately 35 days. During that time, all pressurized and unpressurized cargoes were transferred to the ISS while KOUNOTORI5 was loaded with waste and experimental devices which had completed their roles. As of today’s re-entry, the KOUNOTORI5 mission was fully accomplished, marking its fifth consecutive success.

The KOUNOTORI has the biggest capability for cargo transportation in the world which supports the basis of ISS operations. Therefore, the mission received international acclaim and great expectations. Under such pressure, we completed the mission thanks to the combined efforts of Astronaut Yui, the JAXA ground operation team, and Astronaut Wakata from the NASA Mission Control Center. I believe that this success demonstrated Japan’s accumulated space capability and reliability to international society.

The KOUNOTORI5 carried not only necessities for ISS operations, but also experiment devices which enhance the capability of the Japanese Experiment Module “Kibo”. JAXA accelerates space experiments which contribute to Japan's national strategy of science and technology and promotes commercial utilization. Therefore, JAXA is planning to conduct various experiment by using devices such as the “Mouse Habitat Unit” for studying human’s aging mechanism using mice, the “Electrostatic Levitation Furnace” for measuring the thermophysical properties of high-temperature melts covering metals to insulators, and the “Calorimetric Electron Telescope (CALET)” for closing in upon the mysteries of dark matter. ISS crew members, including Astronaut Yui and the ground operation team, are preparing experiments with these devices.

Finally, I would like to thank every domestic and international organization and Japanese citizens for supporting us on this mission.

Naoki Okumura, President of Japan Aerospace Exploration Agency (JAXA).

For more information about Japan Aerospace Exploration Agency (JAXA), visit:

Images, Text, Credits: Japan Aerospace Exploration Agency (JAXA)/National Research and Development Agency/NASA.


SMOS meets ocean monsters

ESA - SMOS Mission logo.

30 September 2015

ESA’s SMOS and two other satellites are together providing insight into how surface winds evolve under tropical storm clouds in the Pacific Ocean. This new information could to help predict extreme weather at sea.

The storms below

This year, a particularly strong El Niño is resulting in much higher surface ocean temperatures than normal. The surplus heat that is being drawn into the atmosphere is helping to breed tropical cyclones – Pacific Ocean monsters. With eight major hurricanes already, this year’s hurricane season is the fifth most active in the Eastern Tropical Pacific since 1971.

At the end of August, three category-4 hurricanes developed in parallel near Hawaii.

A collage from NASA’s Terra satellite captured the Kilo, Ignacio and Jimena hurricanes beautifully.

However, a special set of eyes is needed to see through the clouds that are so characteristic of these mighty storms so that the speed of the wind at the ocean surface can be measured.

Hurricane triplets

This information is essential to forecast marine weather and waves, and to predict the path that the storm may take so that mariners receive adequate warning of danger.

The microwave detector on SMOS yields information on soil moisture and ocean salinity. Going beyond its original scientific objectives, ESA pioneered the application of SMOS measurements to study wind speeds over the ocean.

Taking this even further, measurements from two other satellites, NASA’s SMAP and Japan’s GCOM-W, which carry differing low-frequency microwave instruments, are being used with readings from SMOS to glean new information about surface winds under hurricanes.

Hurricanes change temperature of sea surface

Combining data from multiple satellites in this way provides a unique view of how the surface wind speed evolves under tropical storms in unprecedented detail. This will greatly improve the information on the initial conditions of tropical cyclones fed into weather forecasting, and hence their prediction.

Scientists from Ifremer in France and the Met Office in the UK are assessing these new data and how they could be integrated into hurricane forecasting.

Measurements of sea-surface temperatures reveal cold-water wakes trailing the three recent hurricanes, highlighting the power these winds have in stirring the upper ocean and bringing cooler deep waters to the surface.

Changes in chlorophyll concentration

Interactions between the sea and atmosphere on this scale have implications for hurricane forecasting centres and for ocean forecasting systems such as Europe’s Copernicus Marine Environmental Monitoring Service.

Nicolas Reul from Ifremer said, “In addition to improving marine forecasting, the combination of data from sensors on different satellites will definitively enhance our understanding of ocean–atmosphere interactions in intense storms.

“Yet the future of this type of satellite measurement remains uncertain, as follow-on missions are not guaranteed.”

SMOS in orbit

Craig Donlon, ESA’s ocean scientist, added, “Highlighting the societal benefits of new measurement approaches and Earth observation technologies is part of our core business.

“The exciting results emerging from this project demonstrate the importance of passive microwave sensors for extreme weather prediction and for understanding air–sea interactions, and the need to study future mission concepts that combine different microwave channels on a single satellite.”

Related missions:

NASA Soil Moisture Active Passive:

NASA Aquarius:




Related links:

Support to Science Element:



NOAA Central Pacific Hurricane Center:

Copernicus Marine Environmental Monitoring Service:

European Commission Copernicus site:

Images, Video, Text, Credits: ESA/NASA/Ifremer–N. Reul, J. Tenerelli & E. Zabolotskikh /ESA SMOS+STORM project and REMSS/GSFC/OBPG/AOES Medialab.

Best regards,