samedi 14 juin 2014

Spacecraft Glonass-M was successfully launched into orbit












ROSCOSMOS -  GLONASS logo.

15/06/2014

 Preparation of the Soyuz-2.1b carrier rocket for launch of the GLONASS-M

June 14 at 21 hours 17 minutes Moscow time from the launch complex of the platform 43 State Test Cosmodrome Ministry of Defense of the Russian Federation (the cosmodrome Plesetsk) made space rocket Soyuz-2.1b with the upper stage (RB) "Fregat" and spacecraft (SC) Glonass-M. Start calculation made joint Russian Defense Ministry experts and enterprises aerospace industry.

 Launch of the Soyuz-2.1b carrier rocket with GLONASS-M

In accordance with cyclogram flight spacecraft Glonass-M (manufactured by JSC "Information Satellite Systems them. Academician Reshetnev" Zheleznogorsk) injected into the target orbit and adopted by the management. He will join the existing constellation of domestic global navigation satellite system GLONASS.

Rocket Soyuz-2.1b established in FSUE "SRP TsSKB Progress" (Samara), the upper stage Fregat made in FSUE NPO. Lavochkin.

GLONASS-M Satellite

GLONASS system is defined as a dual-use system that provides the solution of problems in the interests of the Russian Defense Ministry and civilian users. Access to civilian navigation signals of global navigation satellite system GLONASS available to Russian and foreign consumers at no cost and without restrictions.

ROSCOSMOS Press Release: http://www.federalspace.ru/20685/

Images, Text, Credits: Roscosmos press service / ROSCOSMOS / Günter Space Page / Translation: Orbiter.ch Aerospace.

Greetings, Orbiter.ch

vendredi 13 juin 2014

Station Crew Wraps Up Week With Medical Research












ISS - Expedition 40 Mission patch.

June 13, 2014

The six-person Expedition 40 crew of the International Space Station wrapped up another workweek in space Friday supporting medical and physics research, maintaining station systems and gearing up for next week’s spacewalk.

Following the crew’s normal 2 a.m. EDT reveille, Commander Steve Swanson and Flight Engineers Reid Wiseman and Alexander Gerst participated in a variety of experiments aimed at understanding the effects of long-duration spaceflight on the human body and developing countermeasures to mitigate the health risks. This research is vitally important as NASA works toward sending humans on longer voyages beyond low Earth orbit.


Image above: Flight Engineer Alexander Gerst enjoys the view of Earth from the windows in the cupola of the International Space Station. Image Credit: NASA.

Swanson began his day with the Sprint investigation, which measures the effectiveness of high-intensity, low-volume exercise training in minimizing the loss of muscle mass and bone density that occurs during spaceflight. Station crew members currently work out around 2 ½-hours every day, and the researchers behind Sprint aim to reduce that total exercise time while maintaining crew fitness.

Wiseman meanwhile served as the subject for a session of the Cardio Ox study, which is investigating the risks of cardiovascular disease related to long-duration spaceflight. With guidance from the ground team, Gerst performed an ultrasound scan on Wiseman and measured his blood pressure. Results from this experiment will help researchers determine if biological markers of oxidative and inflammatory stress are elevated during and after spaceflight, and how those markers correlate with the long-term health changes in astronauts.


Image above: Flight Engineer Reid Wiseman, equipped with a bungee harness, exercises on the Combined Operational Load Bearing External Resistance Treadmill (COLBERT) in the Tranquility node of the International Space Station. Image Credit: NASA.

Wiseman also logged his meals and followed a prescribed diet for the Pro K study as nutritionists monitor how dietary changes may affect spaceflight-related bone loss.

For the Circadian Rhythms investigation, Gerst donned sensors and an armband monitor to track his body’s core temperature over a 36-hour period. Since the station orbits the Earth 16 times a day, an astronaut’s body clock can get disrupted from experiencing a sunrise or sunset every 45 minutes. Results from this investigation will provide insights into the adaptations of the human autonomic nervous system in space and will help optimize crew schedules and workplace illumination.

Gerst also set up samples and configured hardware for a combustion experiment known as the Burning and Suppression of Solids, or BASS. In the absence of gravity, materials burn quite differently, and some materials may actually become more flammable than on Earth. BASS takes a look at how a variety of materials burn and extinguish in microgravity, which will lead to improvements in spacecraft materials selection and strategies for putting out accidental fires aboard spacecraft. The research also provides scientists with improved computational models that will aid in the design of fire detection and suppression systems here on Earth.


Image above: Flight Engineer Alexander Gerst works with the Burning and Suppression of Solids experiment aboard in the International Space Station. Image Credit: NASA TV.

Working in the station’s Kibo laboratory, Swanson swapped out a seedling test sample chamber inside the Cell Biology Experiment Facility, which includes a centrifuge for controlled gravity levels. The Resist Tubule experiment examines the mechanisms for gravity resistance in plants to help researchers learn more about the evolution of plants and enable efficient plant production both on Earth and in space.

After a break for lunch, Swanson and Wiseman worked together in the station’s Tranquility node to remove and replace a failed heat exchanger for the Common Cabin Air Assembly, a component of the station’s Environmental Control and Life Support System which collects condensate out of the air.

In the Quest airlock, Gerst wrapped up verification work on the new spacesuit delivered to the station by the SpaceX-3 commercial resupply services mission in April. Gerst performed a water dump and fill of the spacesuit to satisfy maintenance requirements for on-orbit stowage. Since this is the first U.S. spacesuit that has traveled to the station on anything other than a space shuttle, Gerst has been conducting an extra-thorough checkout of the suit to certify it for readiness.

With their own spacewalk looming next week, Flight Engineers Alexander Skvortsov and Oleg Artemyev attached spacewalk tools and other hardware to their Russian Orlan spacesuits, including gear on loan from their NASA crewmates.

During the 6 ½-hour excursion slated to begin at 9:50 a.m. Thursday, the two spacewalking cosmonauts will mount a new integrated command and telemetry system on the Zvezda service module and replace a payload rack on the Russian segment with a payload boom previously installed in a temporary location. NASA Television coverage of the Russian spacewalk begins at 9:15 a.m. Thursday.

The spacewalk will be the 180th in support of space station assembly and maintenance and the first for both Skvortsov and Artemyev.


Image above: Rio de Janeiro and Sao Paulo as Seen From the International Space Station. Image Credit: NASA/Reid Wiseman.

As fans around the world tune in to World Cup 2014, a few fans out of this world will be watching, too. United States astronauts Reid Wiseman and Steve Swanson and German astronaut Alexander Gerst will be cheering on their teams from some 230 miles above Earth aboard the International Space Station.

Here, Wiseman captures an image of Rio de Janeiro and Sao Paulo at night as the International Space Station orbits the Earth. Sao Paulo is the farthest cluster of lights on the right side and Rio de Janeiro is closer to the middle of the picture. There are three World Cup 2014 stadium cities in one picture: Arena de Sao Paulo, Estadio Mineirao (Belo Horizonte), and Estadio Do Maracana (Rio de Janeiro).

The third Russian cosmonaut aboard the station, Flight Engineer Max Suraev, worked with Skvortsov to install a docking mechanism for the ISS Progress 55 cargo craft connected to the Pirs docking compartment. Suraev also conducted an audit of the docking and internal transfer system tools and equipment aboard the station.

Over the weekend, the station’s residents will have some free time to relax, speak with family members back on Earth and take care of weekly housekeeping chores. They’ll also have a chance to catch up on the action at the World Cup 2014 games in Brazil. The crew sent down a special message earlier to wish good luck to all the players and teams.

View World Cup 2014 message from crew: http://youtu.be/sLwW3pdXkFo

Astronauts to Watch World Cup Aboard Station: http://www.nasa.gov/content/astronauts-to-watch-world-cup-aboard-space-station/

Related links:

Sprint investigation: http://www.nasa.gov/mission_pages/station/research/experiments/972.html

Cardio Ox study: http://www.nasa.gov/mission_pages/station/research/experiments/931.html

Circadian Rhythms investigation: http://www.nasa.gov/mission_pages/station/research/experiments/892.html

Burning and Suppression of Solids, or BASS: http://www.nasa.gov/mission_pages/station/research/experiments/735.html

Images (mentioned), Text, Credit: NASA.

Best regards, Orbiter.ch

Experiments Recreate Aromatic Flavors of Titan










NASA / ESA - Cassini Mission International logo.

June 13, 2014

NASA scientists have created a new recipe that captures key flavors of the brownish-orange atmosphere around Saturn’s largest moon, Titan.

The recipe is used for lab experiments designed to simulate Titan’s chemistry. With this approach, the team was able to classify a previously unidentified material discovered by NASA’s Cassini spacecraft in the moon’s smoggy haze.

“Now we can say that this material has a strong aromatic character, which helps us understand more about the complex mixture of molecules that makes up Titan’s haze,” said Melissa Trainer, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.


Image above: In lab experiments NASA scientists matched the spectral signature of an unknown material the Cassini spacecraft detected in Titan's atmosphere at far-infrared wavelengths. The material contains aromatic hydrocarbons that include nitrogen, a subgroup called polycyclic aromatic nitrogen heterocycles. Image Credit: NASA/Goddard/JPL.

The material had been detected earlier in data gathered by Cassini’s Composite Infrared Spectrometer, an instrument that makes observations at wavelengths in the far infrared region, beyond red light. The spectral signature of the material suggested it was made up of a mixture of molecules.

To investigate that mixture, the researchers turned to the tried-and-true approach of combining gases in a chamber and letting them react. The idea is that if the experiment starts with the right gases and under the right conditions, the reactions in the lab should yield the same products found in Titan’s smoggy atmosphere. The process is like being given a slice of cake and trying to figure out the recipe by tasting it. If you can make a cake that tastes like the original slice, then you chose the right ingredients.


Image above: Titan's atmosphere makes Saturn's largest moon look like a fuzzy orange ball in this natural-color view from the Cassini spacecraft. Cassini captured this image in 2012. Image Credit: NASA/JPL-Caltech/Space Science Institute.

The challenge is that the possibilities are almost limitless in this case. Titan’s dirty orange color comes from a mixture of hydrocarbons (molecules that contain hydrogen and carbon) and nitrogen-carrying chemicals called nitriles. The family of hydrocarbons already has hundreds of thousands of members, identified from plants and fossil fuels on Earth, and more could exist.

The logical starting point was to begin with the two gases most plentiful in Titan’s atmosphere: nitrogen and methane. But these experiments never produced a mixture with a spectral signature to match to the one seen by Cassini; neither have similar experiments conducted by other groups.


Image above: This Cassini image from 2012 shows Titan and its parent planet Saturn. Image Credit: NASA/JPL-Caltech/SSI.

Promising results finally came when the researchers added a third gas, essentially tweaking the flavors in the recipe for the first time. The team began with benzene, which has been identified in Titan’s atmosphere, followed by a series of closely related chemicals that are likely to be present there. All of these gases belong to the subfamily of hydrocarbons known as aromatics.

The outcome was best results were obtained when the scientists chose an aromatic that contained nitrogen. When team members analyzed those lab products, they detected spectral features that matched up well with the distinctive signature that had been extracted from the Titan data by Carrie Anderson, a Cassini participating scientist at Goddard and a co-author on this study.

“This is the closest anyone has come, to our knowledge, to recreating with lab experiments this particular feature seen in the Cassini data,” said Joshua Sebree, the lead author of the study, available online in Icarus. Sebree is a former postdoctoral fellow at Goddard who is now an assistant professor at the University of Northern Iowa in Cedar Falls.

Image above: Artist concept of Cassini spacecraft. Image Credit: NASA/JPL

Now that the basic recipe has been demonstrated, future work will concentrate on tweaking the experimental conditions to perfect it.

“Titan’s chemical makeup is veritable zoo of complex molecules,” said Scott Edgington, Cassini Deputy Project Scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “With the combination of laboratory experiments and Cassini data, we gain an understanding of just how complex and wondrous this Earth-like moon really is.”

The laboratory experiments were funded by NASA’s Planetary Atmospheres program. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. Goddard built and manages the Composite Infrared Spectrometer.

Related Links:

NASA's main Cassini website: http://www.nasa.gov/cassini

ESA's main Cassini website: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Cassini project website at NASA JPL: http://saturn.jpl.nasa.gov/

More information about the Composite Infrared Spectrometer: http://cirs.gsfc.nasa.gov/

NASA's Goddard Space Flight Center / Elizabeth Zubritzky.

Greetings, Orbiter.ch

Cracks in Pluto's Moon Could Indicate it Once Had an Underground Ocean














NASA - Galileo Mission patch / NASA / ESA - Cassini Mission to Saturn patch.

June 13, 2014

If the icy surface of Pluto's giant moon Charon is cracked, analysis of the fractures could reveal if its interior was warm, perhaps warm enough to have maintained a subterranean ocean of liquid water, according to a new NASA-funded study.

Pluto is an extremely distant world, orbiting the sun more than 29 times farther than Earth. With a surface temperature estimated to be about 380 degrees below zero Fahrenheit (around minus 229 degrees Celsius), the environment at Pluto is far too cold to allow liquid water on its surface. Pluto's moons are in the same frigid environment.


Image above: This artist concept shows Pluto and some of its moons, as viewed from the surface of one of the moons. Pluto is the large disk at center. Charon is the smaller disk to the right. Image Credit: NASA, ESA and G. Bacon (STScI).

Pluto's remoteness and small size make it difficult to observe, but in July of 2015, NASA's New Horizons spacecraft will be the first to visit Pluto and Charon, and will provide the most detailed observations to date.

"Our model predicts different fracture patterns on the surface of Charon depending on the thickness of its surface ice, the structure of the moon's interior and how easily it deforms, and how its orbit evolved," said Alyssa Rhoden of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "By comparing the actual New Horizons observations of Charon to the various predictions, we can see what fits best and discover if Charon could have had a subsurface ocean in its past, driven by high eccentricity." Rhoden is lead author of a paper on this research now available online in the journal Icarus.

Some moons around the gas giant planets in the outer solar system have cracked surfaces with evidence for ocean interiors – Jupiter's moon Europa and Saturn's moon Enceladus are two examples.


Image above: This is a mosaic of images showing cracks in Saturn's moon Enceladus taken by the Cassini spacecraft during its close flyby on March 9 and July 14, 2005. Image Credit: NASA/JPL/Space Science Institute.

As Europa and Enceladus move in their orbits, a gravitational tug-of-war between their respective parent planets and neighboring moons keeps their orbits from becoming circular. Instead, these moons have eccentric (slightly oval-shaped) orbits, which raise daily tides that flex the interior and stress the surface. It is thought that tidal heating has extended the lifetimes of subsurface oceans on Europa and Enceladus by keeping their interiors warm.


Images above: Two views from NASA's Galileo mission of Jupiter's moon Europa. The left image shows the approximate natural color appearance of Europa. The right image is a false-color composite of violet, green and infrared images to enhance color differences in the predominantly water-ice crust of Europa. Image Credit: NASA/JPL/DLR.

In Charon's case, this study finds that a past high eccentricity could have generated large tides, causing friction and surface fractures. The moon is unusually massive compared to its planet, about one-eighth of Pluto's mass, a solar system record. It is thought to have formed much closer to Pluto, after a giant impact ejected material off the planet's surface. The material went into orbit around Pluto and coalesced under its own gravity to form Charon and several smaller moons.


Image above: This is a close-up view of the fractures on Enceladus taken by Cassini during its flyby Nov. 21, 2009. The area, about 504 kilometers (313 miles) across, focuses on Baghdad Sulcus, a fracture in the south polar region. Image Credit: NASA/JPL/SSI.

Initially, there would have been strong tides on both worlds as gravity between Pluto and Charon caused their surfaces to bulge toward each other, generating friction in their interiors. This friction would have also caused the tides to slightly lag behind their orbital positions. The lag would act like a brake on Pluto, causing its rotation to slow while transferring that rotational energy to Charon, making it speed up and move farther away from Pluto.

"Depending on exactly how Charon's orbit evolved, particularly if it went through a high-eccentricity phase, there may have been enough heat from tidal deformation to maintain liquid water beneath the surface of Charon for some time," said Rhoden. "Using plausible interior structure models that include an ocean, we found it wouldn't have taken much eccentricity (less than 0.01) to generate surface fractures like we are seeing on Europa."

"Since it's so easy to get fractures, if we get to Charon and there are none, it puts a very strong constraint on how high the eccentricity could have been and how warm the interior ever could have been," adds Rhoden. "This research gives us a head start on the New Horizons arrival – what should we look for and what can we learn from it. We're going to Pluto and Pluto is fascinating, but Charon is also going to be fascinating."

Based on observations from telescopes, Charon's orbit is now in a stable end state: a circular orbit with the rotation of both Pluto and Charon slowed to the point where they always show the same side to each other. Its current orbit is not expected to generate significant tides, so any ancient underground ocean may be frozen by now, according to Rhoden.

Since liquid water is a necessary ingredient for known forms of life, the oceans of Europa and Enceladus are considered to be places where extraterrestrial life might be found. However, life also requires a useable energy source and an ample supply of many key elements, such as carbon, nitrogen, and phosphorus. It is unknown if those oceans harbor these additional ingredients, or if they have existed long enough for life to form. The same questions would apply to any ancient ocean that may have existed beneath the icy crust of Charon.

This research was funded by the NASA Postdoctoral Program at the NASA Goddard Space Flight Center, administered by Oak Ridge Associated Universities, and NASA Headquarters through the Science Innovation Fund.

Related Links:

NASA's Galileo websites: http://science.nasa.gov/missions/galileo/ and https://solarsystem.nasa.gov/galileo/

NASA's main Cassini website: http://www.nasa.gov/cassini

ESA's main Cassini website:  http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center / Bill Steigerwald.

Cheers, Orbiter.ch

Hubble Eyes Golden Rings of Star Formation












NASA - Hubble Space Telescope patch.

June 13, 2014


Taking center stage in this new NASA/ESA Hubble Space Telescope image is a galaxy known as NGC 3081, set against an assortment of glittering galaxies in the distance. Located in the constellation of Hydra (The Sea Serpent), NGC 3081 is located over 86 million light-years from us. It is known as a type II Seyfert galaxy, characterized by its dazzling nucleus.

NGC 3081 is seen here nearly face-on. Compared to other spiral galaxies, it looks a little different. The galaxy's barred spiral center is surrounded by a bright loop known as a resonance ring. This ring is full of bright clusters and bursts of new star formation, and frames the supermassive black hole thought to be lurking within NGC 3081 — which glows brightly as it hungrily gobbles up in-falling material.

These rings form in particular locations known as resonances, where gravitational effects throughout a galaxy cause gas to pile up and accumulate in certain positions. These can be caused by the presence of a "bar" within the galaxy, as with NGC 3081, or by interactions with other nearby objects. It is not unusual for rings like this to be seen in barred galaxies, as the bars are very effective at gathering gas into these resonance regions, causing pile-ups which lead to active and very well-organized star formation.

Hubble snapped this magnificent face-on image of the galaxy using the Wide Field Planetary Camera 2. This image is made up of a combination of ultraviolet, optical, and infrared observations, allowing distinctive features of the galaxy to be observed across a wide range of wavelengths.

For images and more information about Hubble, visit: http://www.nasa.gov/hubble and http://www.spacetelescope.org/

Image Credits: ESA/Hubble & NASA; acknowledgement: R. Buta (University of Alabama), Text Credit: European Space Agency.

Best regards, Orbiter.ch

Giant Telescopes Pair Up to Image Near-Earth Asteroid











Asteroid Watch.

June 13, 2014


Images above: NASA scientists used Earth-based radar to produce these sharp views - an image montage and a movie sequence -- of the asteroid designated "2014 HQ124" on June 8, 2014. Image Credit: NASA/JPL-Caltech/Arecibo Observatory/USRA/NSF.

NASA scientists using Earth-based radar have produced sharp views of a recently discovered asteroid as it slid silently past our planet. Captured on June 8, 2014, the new views of the object designated “2014 HQ124" are some of the most detailed radar images of a near-Earth asteroid ever obtained.

The radar observations were led by scientists Marina Brozovic and Lance Benner of NASA's Jet Propulsion Laboratory, Pasadena, California.  The JPL researchers worked closely with Michael Nolan, Patrick Taylor, Ellen Howell and Alessondra Springmann at Arecibo Observatory in Puerto Rico to plan and execute the observations.

According to Benner, 2014 HQ124 appears to be an elongated, irregular object that is at least 1,200 feet (370 meters) wide on its long axis. "This may be a double object, or 'contact binary,' consisting of two objects that form a single asteroid with a lobed shape," he said. The images reveal a wealth of other features, including a puzzling pointy hill near the object's middle, on top as seen in the images.

The 21 radar images were taken over a span of four-and-a-half hours. During that interval, the asteroid rotated a few degrees per frame, suggesting its rotation period is slightly less than 24 hours.

At its closest approach to Earth on June 8, the asteroid came within 776,000 miles (1.25 million kilometers), or slightly more than three times the distance to the moon. Scientists began observations of 2014 HQ124 shortly after the closest approach, when the asteroid was between about 864,000 miles and 902,000 miles (1.39 million kilometers and 1.45 million kilometers) from Earth.

Each image in the collage and movie represents 10 minutes of data.

The new views show features as small as about 12 feet (3.75 meters) wide. This is the highest resolution currently possible using scientific radar antennas to produce images. Such sharp views for this asteroid were made possible by linking together two giant radio telescopes to enhance their capabilities.

To obtain the new views, researchers paired the 230-foot (70-meter) Deep Space Network antenna at Goldstone, California, with two other radio telescopes, one at a time. Using this technique, the Goldstone antenna beams a radar signal at an asteroid and the other antenna receives the reflections. The technique dramatically improves the amount of detail that can be seen in radar images.

To image 2014 HQ124, the researchers first paired the large Goldstone antenna with the 1,000-foot (305-meter) Arecibo radio telescope in Puerto Rico. They later paired the large Goldstone dish with a smaller companion, a 112-foot (34-meter) antenna, located about 20 miles (32 kilometers) away.

video
Radar data of asteroid 2014 HQ124 taken over four hours on June 8, 2014

A recent equipment upgrade at Arecibo enabled the two facilities to work in tandem to obtain images with this fine level of detail for the first time.

"By itself, the Goldstone antenna can obtain images that show features as small as the width of a traffic lane on the highway," said Benner. "With Arecibo now able to receive our highest-resolution Goldstone signals, we can create a single system that improves the overall quality of the images."

The first five images in the new sequence -- the top row in the collage -- represent the data collected by Arecibo, and are 30 times brighter than what Goldstone can produce observing on its own.

Scientists were fortunate to be able to make these radar observations at all, as this particular asteroid was only recently discovered. NASA's NEOWISE mission, a space telescope adapted for scouting the skies for the infrared light emitted by asteroids and comets, first spotted the space rock on April 23, 2014. Additional information about the asteroid's discovery and its orbit was shared in a previous Web story online at: http://www.jpl.nasa.gov/news/news.php?release=2014-178

For asteroids, as well as comets, radar is a powerful tool for studying the objects’ size, shape, rotation, surface features and orbits. Radar measurements of asteroid distances and velocities enable researchers to compute orbits much further into the future than if radar observations were not available.

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and identifies their orbits to determine if any could be potentially hazardous to our planet. To date, U.S. assets have discovered more than 98 percent of the known near-Earth objects.

Along with the resources NASA puts into understanding asteroids, it also partners with other U.S. government agencies, university-based astronomers and space science institutes across the country that are working to find, track and understand these objects better, often with grants, interagency transfers and other contracts from NASA. In addition, NASA values the work of numerous highly skilled amateur astronomers, whose accurate observational data helps improve asteroid orbits after they are found.

The contributions of JPL engineers Jon Giorgini, Joseph Jao and Clement Lee were critical to the successful execution of these observations.

Through its Asteroid Initiative, NASA is developing a first-ever mission to identify, capture and redirect a near-Earth asteroid to a stable orbit around the moon with a robotic spacecraft. Astronauts aboard an Orion spacecraft, launched by a Space Launch System rocket, will explore the asteroid in the 2020s, returning to Earth with samples. Experience in human spaceflight beyond low-Earth orbit through this Asteroid Redirect Mission will help NASA test new systems and capabilities needed to support future human missions to Mars. The Initiative also includes an Asteroid Grand Challenge, which is seeking the best ideas to find all asteroid threats to human populations and accelerate the work NASA already is doing for planetary defense.

JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.

More information about asteroids and near-Earth objects is available at:
http://neo.jpl.nasa.gov/ and http://www.jpl.nasa.gov/asteroidwatch

Twitter updates are at:
http://www.twitter.com/asteroidwatch

Images (mentioned), Video, Text, Credits: NASA / JPL / Preston Dyches.

Greetings, Orbiter.ch

jeudi 12 juin 2014

Herschel Sees Budding Stars and a Giant, Strange Ring










NASA / ESA  - Herschel Mission patch.

June 12, 2014

The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. The observations have revealed numerous clumps of material, a baker's dozen of which may evolve into the most powerful kinds of stars in the universe. Herschel is a European Space Agency mission with important NASA contributions.


Image above: The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538. Image credit: ESA/NASA/JPL-Caltech/Whitman College.

"We have looked at NGC 7538 with Herschel and identified 13 massive, dense clumps where colossal stars could form in the future," said paper lead author Cassandra Fallscheer, a visiting assistant professor of astronomy at Whitman College in Walla Walla, Washington, and lead author of the paper published in The Astrophysical Journal. "In addition, we have found a gigantic ring structure and the weird thing is, we're not at all sure what created it."

NGC 7538 is relatively nearby, at a distance of about 8,800 light-years and located in the constellation Cepheus. The cloud, which has a mass on the order of 400,000 suns, is undergoing an intense bout of star formation. Astronomers study stellar nurseries such as NGC 7538 to better learn how stars come into being. Finding the mysterious ring, in this case, came as an unexpected bonus.

The cool, dusty ring has an oval shape, with its long axis spanning about 35 light-years and its short axis about 25 light-years. Fallscheer and her colleagues estimate that the ring possesses the mass of 500 suns. Additional data from the James Clerk Maxwell Telescope, located at the Mauna Kea Observatory in Hawaii, further helped characterize the odd ovoid. Astronomers often see ring and bubble-like structures in cosmic dust clouds. The strong winds cast out by the most massive stars, called O-type stars, can generate these expanding puffs, as can their explosive deaths as supernovas. But no energetic source or remnant of a deceased O-type star, such as a neutron star, is apparent within the center of this ring. It is possible that a big star blew the bubble and, because stars are all in motion, subsequently left the scene, escaping detection.

The observations were taken as part of the Herschel OB Young Stellar objects (HOBYS) Key Programme. The "OB" refers to the two most massive kinds of stars, O-type and B-type. These bright blue, superhot, short-lived stars end up exploding as supernovas, leaving behind either incredibly dense neutron stars or even denser black holes.

Stars of this caliber form from gassy, dusty clumps with initial masses dozens of times greater than the sun's; the 13 clumps spotted in NGC 7358, some of which lie along the edge of the mystery ring, all are more than 40 times more massive than the sun. The clumps gravitationally collapse in on themselves, growing denser and hotter in their cores until nuclear fusion ignites and a star is born. For now, early in the star-formation process, the clumps remain quite cold, just a few tens of degrees above absolute zero. At these temperatures, the clumps emit the bulk of their radiation in the low-energy, submillimeter and infrared light that Herschel was specifically designed to detect.

As astronomers continue probing these budding O-type giants in NGC 7358, the follow-up observations with other telescopes should also help in solving the puzzle of the humongous, dusty ring. "Further research to determine the mechanism responsible for creating the ring structure is necessary," said Fallscheer.

Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. While the observatory stopped making science observations in April 2013, after running out of liquid coolant as expected, scientists continue to analyze its data. NASA's Herschel Project Office is based at the Jet Propulsion Laboratory in Pasadena, California. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the U.S. astronomical community.

More information is online at:

http://www.herschel.caltech.edu

http://www.nasa.gov/herschel

http://www.esa.int/SPECIALS/Herschel

Images (mentioned), Text, Credits: NASA / JPL / Whitney Clavin.

Greetings, Orbiter.ch

New NASA Space Observatory to Study Carbon Conundrums












NASA - OCO-2 Mission logo.

June 12, 2014

NASA’s first spacecraft dedicated to measuring carbon dioxide levels in Earth’s atmosphere is in final preparations for a July 1 launch from Vandenberg Air Force Base, California.


Image above: Artist's rendering of NASA's Orbiting Carbon Observatory (OCO)-2, one of five new NASA Earth science missions set to launch in 2014, and one of three managed by JPL. Image Credit: NASA-JPL/Caltech.

The Orbiting Carbon Observatory-2 (OCO-2) mission will provide a more complete, global picture of the human and natural sources of carbon dioxide, as well as their “sinks,” the natural ocean and land processes by which carbon dioxide is pulled out of Earth’s atmosphere and stored. Carbon dioxide, a critical component of Earth’s carbon cycle, is the leading human-produced greenhouse gas driving changes in Earth’s climate.

“Carbon dioxide in the atmosphere plays a critical role in our planet's energy balance and is a key factor in understanding how our climate is changing,” said Michael Freilich, director of NASA’s Earth Science Division in Washington. “With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future."

video
Orbiting Carbon Observatory-2 (OCO-2): NASA's New Carbon Counter

Video above: NASA's Orbiting Carbon Observatory-2, launching July 2014, will study carbon dioxide in the atmosphere and help us understand how fast it will build up in the future.

OCO-2 will launch on a United Launch Alliance Delta II rocket and maneuver into a 438-mile (705-kilometer) altitude, near-polar orbit. It will become the lead satellite in a constellation of five other international Earth monitoring satellites that circle Earth once every 99 minutes and cross the equator each day near 1:36 p.m. local time, making a wide range of nearly simultaneous Earth observations. OCO-2 is designed to operate for at least two years.

The spacecraft will sample the global geographic distribution of the sources and sinks of carbon dioxide and allow scientists to study their changes over time more completely than can be done with any existing data. Since 2009, Earth scientists have been preparing for OCO-2 by taking advantage of observations from the Japanese GOSAT satellite. OCO-2 replaces a nearly identical NASA spacecraft lost because of a rocket launch mishap in February 2009.

At approximately 400 parts per million, atmospheric carbon dioxide is now at its highest level  in at least the past 800,000 years. The burning of fossil fuels and other human activities are currently adding nearly 40 billion tons of carbon dioxide to the atmosphere each year, producing an unprecedented buildup in this greenhouse gas.

Greenhouse gases trap the sun's heat within Earth's atmosphere, warming the planet’s surface and helping to maintain habitable temperatures from the poles to the equator. Scientists have concluded increased carbon dioxide from human activities, particularly fossil fuel burning and deforestation, has thrown Earth's natural carbon cycle off balance, increasing global surface temperatures and changing our planet's climate.

Currently, less than half the carbon dioxide emitted into Earth’s atmosphere by human activities stays there. Some of the remainder is absorbed by Earth’s ocean, but the location and identity of the natural land sinks believed to be absorbing the rest is not well understood. OCO-2 scientists hope to coax these sinks out of hiding and resolve a longstanding scientific puzzle.

“Knowing what parts of Earth are helping remove carbon from our atmosphere will help us understand whether they will keep doing so in the future,” said Michael Gunson, OCO-2 project scientist at NASA’s Jet Propulsion Laboratory (JPL), Pasadena, California. “Understanding the processes controlling carbon dioxide in our atmosphere will help us predict how fast it will build up in the future. Data from this mission will help scientists reduce uncertainties in forecasts of how much carbon dioxide will be in the atmosphere and improve the accuracy of global climate change predictions.”

OCO-2 measurements will be combined with data from ground stations, aircraft and other satellites to help answer questions about the processes that regulate atmospheric carbon dioxide and its role in Earth’s climate and carbon cycle. Mission data will also help assess the usefulness of space-based measurements of carbon dioxide for monitoring emissions.

The observatory's science instrument features three, high-resolution spectrometers that spread reflected sunlight into its component colors, then precisely measure the intensity of each color. Each spectrometer is optimized to record a different specific color absorbed by carbon dioxide and oxygen molecules in Earth’s atmosphere. The less carbon dioxide in the atmosphere, the more light the spectrometers detect. By analyzing the amount of light, scientists can estimate the relative concentrations of these chemicals.

The new observatory will dramatically increase the number of observations of carbon dioxide, collecting hundreds of thousands of measurements each day when the satellite flies over Earth’s sunlit hemisphere. High-precision, detailed, near-global observations are needed to characterize carbon dioxide's distribution because the concentration of carbon dioxide varies by only a few percent throughout the year on regional to continental scales. Scientists will analyze the OCO-2 data, using computer models similar to those used to predict the weather, to locate and understand the sources and sinks of carbon dioxide.

OCO-2 is a NASA Earth System Science Pathfinder Program mission managed by JPL for NASA's Science Mission Directorate in Washington. Orbital Sciences Corporation in Dulles, Virginia, built the spacecraft bus and provides mission operations under JPL’s leadership. The science instrument was built by JPL, based on the instrument design co-developed for the original OCO mission by Hamilton Sundstrand in Pomona, California. NASA's Launch Services Program at NASA's Kennedy Space Center in Florida is responsible for launch management. JPL is managed for NASA by the California Institute of Technology in Pasadena.

For more information about the Orbiting Carbon Observatory-2, visit: http://oco.jpl.nasa.gov and http://www.nasa.gov/oco2

Follow OCO-2 on Twitter at: https://twitter.com/IamOCO2

OCO-2 is the second of five NASA Earth science missions to be launched this year. NASA monitors Earth’s vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA's Earth science activities in 2014, visit: http://www.nasa.gov/earthrightnow

Image (mentioned), Video, Text, Credits: NASA / Steve Cole / JPL / Alan Buis.

Cheers, Orbiter.ch

mercredi 11 juin 2014

Astronauts to Watch World Cup aboard Space Station














ISS - International Space Station flags logo / ISS - Expedition 40 Mission patch.

June 11, 2014

As fans around the world tune in to World Cup 2014, a few fans out of this world will be watching, too. United States astronauts Reid Wiseman and Steve Swanson and German astronaut Alexander Gerst will be cheering on their teams from some 230 miles above Earth aboard the International Space Station.

video
Astronauts to Watch World Cup Aboard Space Station

Video above: United States astronauts Reid Wiseman and Steve Swanson and German astronaut Alexander Gerst will be cheering on their teams from some 230 miles above Earth aboard the International Space Station. Video Credit: NASA TV.

View NASA's World Cup 2014 page: http://www.nasa.gov/worldcup/

The crew sent down a special message to wish good luck to all the players and teams as they compete in World Cup 2014 in Brazil from June 12 until the final match July 13. The astronauts have trained for years to work together as a unified crew, but the U.S. astronauts and their German crewmate are feeling a little friendly competition: their home countries will play against each other for a chance to advance out of Group G of the World Cup matches. USA and Germany face off on June 26 at Arena Pernambuco in Recife, Brazil.


Image above: (From left) Expedition 40 Commander Steve Swanson and Flight Engineers Alexander Gerst and Reid Wiseman wish soccer fans and the World Cup 2014 "peaceful games." Image Credit: NASA TV.

Reid Wiseman, of NASA, and Alexander Gerst, of the European Space Agency, arrived at the space station on May 28 as part of the Expedition 40/41 crew and are scheduled to spend the next several months living and working in space until they return to Earth in November 2014. Steven Swanson arrived as part of the Expedition 39/40 crew on March 25 and is expected to return home in September 2014.

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

You can Follow Reid Wiseman and Alexander Gerst on Twitter at @Astro_Reid and @Astro_Alex.

Image, Video, Text, Credits: NASA / NASA TV.

Special delivery from CryoSat







ESA - CryoSat 2 Mission logo.

11 June 2014

New data products from ESA’s ice mission open new doors for scientists studying oceans.

Launched in 2010, the polar-orbiting CryoSat was developed to measure the changes in the thickness of polar sea ice, the elevation of the ice sheets that blanket Greenland and Antarctica, and mountain glaciers.

Going above and beyond its ice-monitoring objective, CryoSat is also a valuable source of data for the oceanographic community. The satellite’s radar altimeter can measure sea-level height, waves and detect small, local phenomena in the ocean surface like eddies.

Sea-level detail from CryoSat

ESA has extended the CryoSat portfolio to include additional ocean products, and the datasets are now available to users for both scientific and operational applications.

These new data help to bridge the gap between previous ocean-oriented radar altimetry missions – Jason-1/2 and Envisat – and the future Sentinel-3 mission being developed for Europe’s Copernicus programme.

In addition, CryoSat improves the dataset from the existing satellite missions by reaching closer to the north and south poles thanks to its unusually high-inclination orbit. Measurements from these previously inaccessible latitudes contribute to our knowledge on ocean–cryosphere interactions.

2013 sea-surface topography

The new ocean products from CryoSat help scientists to understand global oceanographic issues, such as ocean–atmosphere interactions, El Niño/La Niña occurrences and sea-level rise.

In particular, the ‘Geophysical Ocean Product’ dataset demonstrates the CryoSat radar’s contribution to the monitoring of eddy variability, from large-scale currents to small-scale instabilities that arise along the larger eddies’ borders.

Studying such complex hydrodynamic features is still a challenging issue that requires high-resolution sampling along the track and frequent revisit time. Integrating the CryoSat dataset with data from other Earth-observing missions should therefore help scientists to understand better the role that eddies play in the mixing and transport of biogeochemical and biological organisms, which represent a critical part of the global carbon cycle.

CryoSat satellite

Another new dataset, called the ‘Intermediate Ocean Product’, provides measurements on wind direction, wave height and sea level. These are being used to improve sea state and weather forecasts – information useful for marine safety and the sustainable management of human activities that affect oceanic ecosystems.

Registered users may access data directly though CryoSat ftp server: ftp://science-pds.cryosat.esa.int

First-time users can register via eohelp@esa.int

Access CryoSat data: https://earth.esa.int/web/guest/missions/esa-operational-eo-missions/cryosat

CryoSatApp (iPhone): http://itunes.apple.com/us/app/esa-cryosat/id484020380?ls=1&mt=8

CryoSatApp (iPad): http://itunes.apple.com/us/app/esa-cryosat-hd/id484090376?ls=1&mt=8

CryoSat: an icy mission: http://www.esa.int/Our_Activities/Observing_the_Earth/CryoSat/CryoSat_an_icy_mission

Images, Text, Credits: ESA / P. Carril/ CNES / CLS.

Greetings, Orbiter.ch

Gigantic Explosions Buried in Dust












ESO - European Southern Observatory logo.

11 June 2014

ALMA probes environment around dark gamma-ray bursts

Gamma-ray burst buried in dust (artist’s impression)

Observations from the Atacama Large Millimeter/submillimeter Array (ALMA) have for the first time directly mapped out the molecular gas and dust in the host galaxies of gamma-ray bursts (GRBs) — the biggest explosions in the Universe. In a complete surprise, less gas was observed than expected, and correspondingly much more dust, making some GRBs appear as “dark GRBs”. This work will appear in the journal Nature on 12 June 2014 and is the first ALMA science result on GRBs to appear. It shows ALMA’s potential to help us to better understand these objects.

Gamma-ray bursts (GRBs) are intense bursts of extremely high energy observed in distant galaxies — the brightest explosive phenomenon in the Universe. Bursts that last more than a couple of seconds are known as long-duration gamma-ray bursts (LGRBs) [1] and are associated with supernova explosions — powerful detonations at the ends of the lives of massive stars.

Gamma-ray burst buried in dust

In just a matter of seconds, a typical burst releases as much energy as the Sun will in its entire ten-billion-year lifetime. The explosion itself is often followed by a slowly fading emission, known as an afterglow, which is thought to be created by collisions between the ejected material and the surrounding gas.

However, some gamma-ray bursts mysteriously seem to have no afterglow — they are referred to as dark bursts. One possible explanation is that clouds of dust absorb the afterglow radiation.

In recent years, scientists have been working to better understand how GRBs form by probing their host galaxies. Astronomers expected that the massive stars that were GRB progenitors would be found in active star-forming regions in these galaxies, which would be surrounded by a large amount of molecular gas — the fuel for star formation. However, there had been no observational result to back up this theory, leaving a long-standing mystery.

For the first time, a Japanese team of astronomers led by Bunyo Hatsukade from the National Astronomical Observatory of Japan, have used ALMA to detect the radio emission from molecular gas in two dark LGRB hosts — GRB 020819B and GRB 051022 — at about 4.3 billion and 6.9 billion light-years, respectively. Although such radio emission had never been detected in the GRB host galaxies, ALMA made it possible with its unprecedentedly high sensitivity [2].

Gamma-ray burst buried in dust (artist’s impression)

Kotaro Kohno, a professor at the University of Tokyo and a member of the research team, said, “We have been searching for molecular gas in GRB host galaxies for over ten years using various telescopes around the world. As a result of our hard work, we finally achieved a remarkable breakthrough using the power of ALMA. We are very excited with what we have achieved.”

Another remarkable achievement made possible by the high resolution of ALMA was uncovering the distribution of molecular gas and dust in GRB host galaxies. Observations of the GRB 020819B revealed a remarkably dust-rich environment in the outskirts of the host galaxy, whereas molecular gas was found only around its centre. This is the first time that such a distribution among GRB host galaxies has been revealed [3]. 

“We didn’t expect that GRBs would occur in such a dusty environment with a low ratio of molecular gas to dust. This indicates that the GRB occurred in an environment quite different from a typical star-forming region,” says Hatsukade. This suggests that massive stars that die as GRBs change the environment in their star-forming region before they explode.

video
Gamma-ray burst buried in dust (artist’s impression)

The research team believes that a possible explanation for the high proportion of dust compared to molecular gas at the GRB site is the difference in their reactions to ultraviolet radiation. Since the bonds between atoms which make up molecules are easily broken by ultraviolet radiation, molecular gas cannot survive in an environment exposed to the strong ultraviolet radiation produced by the hot, massive stars in its star-forming region, including the one that would eventually explode as the observed GRB. Although a similar distribution is also seen in the case of GRB 051022, this has yet to be confirmed due to the lack of resolution (as the GRB 051022 host is located further away than the GRB 020819B host). In any case, these ALMA observations support the hypothesis that it is dust that absorbs the afterglow radiation, causing the dark gamma-ray bursts.

“The results obtained this time were beyond our expectations. We need to carry out further observations with other GRB hosts to see if this could be general environmental conditions of a GRB site. We are looking forward to future research with the improved capability of ALMA,” says Hatsukade.

Notes:

[1] Long-duration gamma-ray bursts (LGRBs), bursts lasting for over two seconds, account for about 70% of observed GRBs.  Developments over the past decade have recognised a new class of GRBs with bursts of less than two seconds, the short-duration GRBs, likely due to merging neutron stars and not associated with supernovae or hypernovae.

[2] The sensitivity of ALMA in this observation was about five times better than other similar telescopes. Early scientific observations with ALMA began with a partial array in 2011 (eso1137). These observations were done with an array only consisting of 24–27 antennas with separations of up to only 125 metres. The completion of the last of the 66 antennas (eso1342) offers great promise of what ALMA may be capable of revealing in the near future, as the antennas can be arranged in different configurations, with maximum distances between antennas varying from 150 metres to 16 kilometres.

[3] The proportion of dust mass to molecular gas mass is about 1% in the interstellar medium in the Milky Way and nearby star-forming galaxies, but it is ten or more times higher in the region surrounding GRB 020819B.

More information:

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

This research was presented in a paper in Nature (12 June 2014) as an article titled “Two gamma-ray bursts from dusty regions with little molecular gas”, by B. Hatsukade et al.

The team is composed of B. Hatsukade (NAOJ, Tokyo, Japan), K. Ohta (Department of Astronomy, Kyoto University, Kyoto, Japan), A. Endo (Kavli Institute of NanoScience, TU Delft, The Netherlands), K. Nakanishi (NAOJ; JAO, Santiago, Chile; The Graduate University for Advanced Studies (Sokendai), Tokyo, Japan), Y. Tamura (Institute of Astronomy [IoA], University of Tokyo, Japan ), T. Hashimoto (NAOJ) and K. Kohno (IoA; Research Centre for the Early Universe, University of Tokyo, Japan).

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 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 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, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

Research paper: http://www.eso.org/public/archives/releases/sciencepapers/eso1418/eso1418a.pdf

More about ALMA: http://www.eso.org/public/teles-instr/alma/

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

Videos of ALMA: http://www.eso.org/public/videos/archive/category/alma/

ALMA brochure: http://www.eso.org/public/products/brochures/alma_brochure_en/

The movie ALMA — In Search of our Cosmic Origins: http://www.eso.org/public/videos/eso1312a/

The ALMA Photo Book In Search of our Cosmic Origins – The Construction of the Atacama Large Millimeter/submillimeter Array: http://www.eso.org/public/products/books/alma-photobook/

More press releases with ALMA: http://www.eso.org/public/news/archive/search/?adv=&facility=36

Related ESO publications:

eso1137: http://www.eso.org/public/news/eso1137/

eso1342: http://www.eso.org/public/news/eso1342/

Images, Video, Text, Credits: ESO / NAOJ / Bunyo Hatsukade (NAOJ), ALMA (ESO/NAOJ/NRAO).

Best regards, Orbiter.ch

Mercury Passes in Front of the Sun, as Seen From Mars










NASA - Mars Science Laboratory (MSL) logo.

June 11, 2014

NASA's Curiosity Mars rover has imaged the planet Mercury passing in front of the sun, visible as a faint darkening that moves across the face of the sun.

This is the first transit of the sun by a planet observed from any planet other than Earth, and also the first imaging of Mercury from Mars. Mercury fills only about one-sixth of one pixel as seen from such great distance, so the darkening does not have a distinct shape, but its position follows Mercury's expected path based on orbital calculations.

(Click on the image for enlarge)

Animation above: This animated blink comparison shows five versions of observations that NASA's Curiosity made about one hour apart while Mercury was passing in front of the sun on June 3, 2014. Two sunspots, each about the diameter of Earth, also appear, moving much less than Mercury during the hour. Image credit: NASA/JPL-Caltech/MSSS/Texas A&M.

The observation by the telephoto camera of Curiosity's two-eyed Mast Camera instrument is available online at: http://www.jpl.nasa.gov/video/?id=1309

"This is a nod to the relevance of planetary transits to the history of astronomy on Earth," said Mark Lemmon of Texas A&M University, College Station, a member of the Mastcan science team. "Observations of Venus transits were used to measure the size of the solar system, and Mercury transits were used to measure the size of the sun."

The observations were made on June 3, 2014, from Curiosity's position inside Gale Crater on Mars. In addition to showing the Mercury transit, the same Mastcam frames show two sunspots approximately the size of Earth. The sunspots move only at the pace of the sun's rotation, much slower than the movement of Mercury.

Many viewers on Earth observed a Venus transit in June 2012, the last visible from Earth this century. The next Mercury transit visible from Earth will be May 9, 2016. Mercury and Venus transits are visible more often from Mars than from Earth, and Mars also offers a vantage point for seeing Earth transits. The next of each type visible from Mars will be Mercury in April 2015, Venus in August 2030 and Earth in November 2084.

Self-Portrait by Curiosity Rover Arm Camera square. Image Credit: NASA/JPL-Caltech/MSSS

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 the California Institute of Technology, Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington.

For more information about Curiosity, visit http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/. You can follow the mission on Facebook at http://www.facebook.com/marscuriosity and on Twitter at http://www.twitter.com/marscuriosity.

Animation (mentioned), Text, Credits: NASA / JPL / Guy Webster.

Cheers, Orbiter.ch

NASA Instruments Begin Science on European Spacecraft Set to Land on Comet












ESA - Rosetta Mission patch.

June 11, 2014


Image above: This artist's impression shows the Rosetta orbiter at comet 67P/Churyumov-Gerasimenko. The image is not to scale. Image Credit: ESA/ATG Medialab.

Three NASA science instruments aboard the European Space Agency's (ESA) Rosetta spacecraft, which is set to become the first to orbit a comet and land a probe on its nucleus, are beginning observations and  sending science data back to Earth.

Launched in March 2004, Rosetta was reactivated January 2014 after a record 957 days in hibernation. Composed of an orbiter and lander, Rosetta’s objective is to arrive at comet 67P/Churyumov-Gerasimenko in August to study the celestial object up close in unprecedented detail and prepare for landing a probe on the comet's nucleus in November.

Rosetta’s lander will obtain the first images taken from a comet’s surface and will provide the first analysis of a comet's composition by drilling into the surface. Rosetta also will be 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 seeding Earth with water, and perhaps even life.

"We are happy to be seeing some real zeroes and ones coming down from our instruments, and cannot wait to figure out what they are telling us," said Claudia Alexander, Rosetta's U.S. project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "Never before has a spacecraft pulled up and parked next to a comet. That is what Rosetta will do, and we are delighted to play a part in such a historic mission of exploration."

Rosetta currently is approaching the main asteroid belt located between Jupiter and Mars,. The spacecraft is still about 300,000 miles (500,000 kilometers) from the comet, but in August the instruments will begin to map its surface.

The three U.S. instruments aboard the spacecraft are the Microwave Instrument for Rosetta Orbiter (MIRO), an ultraviolet spectrometer called Alice, and the Ion and Electron Sensor (IES). They are part of a suite of 11 science instruments aboard the Rosetta orbiter.

MIRO is designed to provide data on how gas and dust leave the surface of the nucleus to form the coma and tail that gives comets their intrinsic beauty. Studying the surface temperature and evolution of the coma and tail provides information on how the comet evolves as it approaches and leaves the vicinity of the sun.

Alice will analyze gases in the comet's coma, which is the bright envelope of gas around the nucleus of the comet developed as a comet approaches the sun. Alice also will measure the rate at which the comet produces water, carbon monoxide and carbon dioxide. These measurements will provide valuable information about the surface composition of the nucleus.

video
Rosetta orbiting the comet

The instrument also will measure the amount of argon present, an important clue about the temperature of the solar system at the time the comet's nucleus originally formed more than 4.6 billion years ago.

IES is part of a suite of five instruments to analyze the plasma environment of the comet, particularly the coma. The instrument will measure the charged particles in the sun's outer atmosphere, or solar wind, as they interact with the gas flowing out from the comet while Rosetta is drawing nearer to the comet's nucleus.

NASA also provided part of the electronics package for the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument. ROSINA will be the first instrument in space with sufficient resolution to be able to distinguish between molecular nitrogen and carbon monoxide, two molecules with approximately the same mass. Clear identification of nitrogen will help scientists understand conditions at the time the solar system was formed.

U.S. scientists are partnering on several non-U.S. instruments and are involved in seven of the mission's 21 instrument collaborations. NASA's Deep Space Network (DSN) is supporting ESA's Ground Station Network for spacecraft tracking and navigation.

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, Göttingen; French National Space Agency, Paris; and the Italian Space Agency, Rome.  JPL 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, Samuel Gulkis. The Southwest Research Institute (San Antonio and Boulder), 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: http://rosetta.jpl.nasa.gov

More information about Rosetta is available at: http://www.esa.int/rosetta

For more information on the DSN, visit: http://deepspace.jpl.nasa.gov/dsn

Image (mentioned), Video, Text, Credits: NASA / Dwayne Brown / JPL / DC Agle / ESA / Markus Bauer.

Greetings, Orbiter.ch