samedi 21 décembre 2013

Spacewalkers Remove Degraded Ammonia Pump

ISS - Expedition 38 Mission patch / EVA - Extra Vehicular Activities patch.

Dec. 21, 2013

Expedition 38 Flight Engineers Rick Mastracchio and Mike Hopkins wrapped up a 5-hour, 28 minute spacewalk outside the International Space Station at 12:29 p.m. EST Saturday, completing the first in a series of excursions aimed at replacing a degraded ammonia pump module associated with one of the station's two external cooling loops that keeps both internal and external equipment cool.

NASA Begins Series of Spacewalks to Fix Coolant Pump on ISS

During Saturday’s spacewalk, the two astronauts focused on removing a degraded pump module from Loop A of the station’s external Active Thermal Control System. That pump module encountered a problem Dec. 11 when an internal valve stuck in an incorrect position, causing temperatures in the station’s cooling lines to drop. On Monday, Mastracchio and Hopkins will venture outside the station again to begin the installation of a replacement pump module. If necessary a third spacewalk would occur on Christmas day to finalize the installation.

Image above: Astronaut Rick Mastracchio works outside the International Space Station during the first of a series of spacewalks to replace a degraded ammonia pump module. Image Credit: NASA TV.

After exiting the Quest airlock, Hopkins made his way out to Saturday’s worksite at center of the Starboard 1 truss segment. Mastracchio meanwhile attached himself to a foot restraint at the end of the station’s 57-foot robotic arm so that Flight Engineer Koichi Wakata, the robotics operator for the spacewalks, could fly Mastracchio to the worksite and position him for his various tasks.

The two spacewalkers first spent some time demating four ammonia fluid line “quick disconnects” from the pump module.

Once the four fluid lines were disconnected, Mastracchio and Hopkins worked to attach the fluid lines to a pump module jumper box, which allows the ammonia to reach the system’s plumbing in the ammonia and nitrogen tanks to keep it in a liquid state.

Image above: Spacewalker Rick Mastracchio works to disconnect the fluid lines from the degraded pump module in this view from the NASA astronaut's helmet camera. Image Credit: NASA TV.

Afterward the spacewalkers installed a generic thermal cover over the pump module jumper and ammonia fluid lines.

With the spacewalk proceeding well ahead of schedule, Mission Control in Houston informed Mastracchio and Hopkins that they could press ahead with the first task originally planned for Monday’s spacewalk –removing the degraded pump module from the starboard truss and attaching it to a stowage location on the Payload Orbital Replacement Unit Accommodation (POA) on the station’s railcar, or Mobile Base System.

While Hopkins set up the POA and an adjustable grapple fixture, Mastracchio removed the five electrical connectors from the pump module and unfastened the module from the truss.

Image above: Astronaut Rick Mastracchio holds the degraded pump module while the International Space Station's robotic arm guides the module to a grapple fixture. Image Credit: NASA TV.

With Mastracchio holding the 780-pound pump while he was attached to the end of the robotic arm, Wakata guided the arm to attach the module to the grapple fixture and activated the snares to hold it in place.

Mastracchio now holds 43 hours and 58 minutes of spacewalking time during seven spacewalks, and Hopkins now holds 5 hours and 28 minutes during one spacewalk.

Saturday’s spacewalk was the 175th in support of space station assembly and maintenance.

For more information about the Space Station (ISS), visit:

Images (mentioned), Video, Text, Credit: NASA / NASA TV.


vendredi 20 décembre 2013

Curiosity Team Upgrades Software, Checks Wheel Wear

NASA - Mars Science Laboratory (MSL) patch.

Dec. 20, 2013

Rocky Mars Ground Where Curiosity Has Been Driving

Image above: NASA's Mars rover Curiosity captured this 360-degree view using its Navigation Camera (Navcam) after a 17-foot (5.3 meter) drive on 477th Martian day, or sol, of the rover's work on Mars (Dec. 8, 2013). Image Credit: NASA/JPL-Caltech.

The team operating NASA's Mars rover Curiosity has completed a software upgrade on the vehicle and is next planning a check of wear and tear on the rover's wheels.

"Curiosity is now operating on version 11 of its flight software," said Jim Erickson of NASA's Jet Propulsion Laboratory, project manager for the NASA Mars Science Laboratory Project, which operates Curiosity.

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

This is the third upgrade version since Curiosity's landing on Mars16 months ago. Completing the switch from version 10 took about a week.  An earlier switch to version 11 prompted an unintended reboot on Nov. 7 and a return to version 10, but the latest transition went smoothly.

These upgrades allow continued advances in the rover's capabilities. For example, version 11 brings expanded capability for using the Curiosity's robotic arm while the vehicle is on slopes. It also improves flexibility for storing information overnight to use in resuming autonomous driving on a second day.

An upcoming activity will be driving to a relatively smooth patch of ground to take a set of images of Curiosity's aluminum wheels, using the Mars Hand Lens Imager (MAHLI) camera at the end of the rover's arm. 

Left-Front Wheel of Curiosity Rover, Approaching Three Miles

Image above: The left-front wheel of NASA's Curiosity Mars rover shows dents and holes in this image taken during the 469th Martian day, or sol, of the rover's work on Mars (Nov. 30, 2013). Image Credit: NASA/JPL-Caltech/MSSS.

"We want to take a full inventory of the condition of the wheels," Erickson said. "Dents and holes were anticipated, but the amount of wear appears to have accelerated in the past month or so. It appears to be correlated with driving over rougher terrain. The wheels can sustain significant damage without impairing the rover's ability to drive. However, we would like to understand the impact that this terrain type has on the wheels, to help with planning future drives."

Curiosity's recent driving has crossed an area that has numerous sharp rocks embedded in the ground.  Routes to future destinations for the mission may be charted to lessen the amount of travel over such rough terrain, compared to smoother ground nearby.

Rocky Mars Ground Where Curiosity Has Been Driving (Stereo)

Image above: NASA's Mars rover Curiosity captured this stereo view using its Navigation Camera (Navcam) after a 17-foot (5.3 meter) drive on 477th Martian day, or sol, of the rover's work on Mars (Dec. 8, 2013). Image Credit: NASA/JPL-Caltech.

NASA's Mars Science Laboratory Project is using Curiosity inside Gale Crater to assess ancient habitable environments and major changes in Martian environmental conditions.  JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington.

More information about Curiosity is online at and . You can follow the mission on Facebook at: and on Twitter at:

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


Long March 3B/E rocket launch the Bolivian Tupac Katari satellite

CASC - China Aerospace Science and Technology Corporation logo.

Dec. 20, 2013

Long March 3B/E launch

A Chinese Long March 3B/E launched the the TKSat-1 satellite for Bolivia on Friday. The launch took place at 16:42 UTC (17:02 GMT / 12:02 p.m. EST) from the LC2 Launch Complex of the Xichang Satellite Launch Center, Sichuan province.

TKSat-1, also known by Tupac Katari, is the result of an agreement signed on December 13, 2010, by the China Great Wall Industry Corporation (CGWIC) and the Bolivia Aerospace Bureau.

With 30 transponders on board (26 Ku-band, 2 C-band and 2 Ka-band), the Tupak Katari satellite is designed for a 15 year mission duration.

Tupak Katari satellite

Tupak Katari will begin orbit operations at 87.2 degrees West longitude in March 2014.

The satellite’s launch mass was 5,100 kg, with 30 transponders, four of which will be used for TV transmission only and the rest for transmission and reception. The satellite will also service Venezuela, Colombia, Ecuador, Peru, Bolivia, Paraguay, Uruguay, North of Chile and Argentina, and the East of Brazil.

The spacecraft is the first communications satellite of Bolivia. It will not only provide communications and broadcasting services to the whole territory of Bolivia and the surrounding areas, but also facilitate the development of civil projects like remote education and telemedicine.

For more information about China Aerospace Science and Technology Corporation (CASC), visit:

Images, Text, Credits: CASC / Xinhua.


Beatles Legend John Lennon Among Those Honored with Mercury Craters

NASA - Messenger Mission to Mercury patch.

Dec. 20, 2013

It’s unlikely that Mercury’s surface is populated with tangerine trees and marmalade skies, but the famous British musician who coined that phrase now has a physical presence on the planet closest to the Sun. The International Astronomical Union (IAU) has named an impact crater on the planet after John Lennon, the British pop music sensation who helped make The Beatles the most popular group of their generation.

Lennon is one of ten newly named craters on the planet, joining 114 other craters named since NASA’s MESSENGER spacecraft's first Mercury flyby in January 2008.

Image above: Mercury's Lennon crater, named for Beatle John Lennon, as seen from NASA's MESSENGER spacecraft. Image Credit: NASA/Johns Hopkins Applied Physics Lab/Carnegie Institution.

“The MESSENGER team is delighted that the IAU has named an additional 10 impact craters on Mercury,” said MESSENGER Principal Investigator Sean Solomon of Columbia University, who suggested Lennon. “We are particularly pleased that eight of the 10 individuals honored made all or many of their artistic contributions in the Twentieth Century, the same century in which the MESSENGER mission was conceived, proposed, and approved for flight. Imagine.”

The IAU has been the arbiter of planetary and satellite nomenclature since its inception in 1919.  In keeping with the established naming theme for craters on Mercury, all of the newly designated features are named after “deceased artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field and have been recognized as art historically significant figures for more than 50 years.”

Messenger spacecraft. Image Credit: NASA

While the notoriety and fame of the namesakes is fun, David Blewett, a MESSENGER participating scientist, says there is a practical reason for naming craters. “After a while, identifying craters by their latitude and longitude becomes laborious,” Blewett says. “Assigning names to the craters makes it easier for scientists to communicate about them, share notes and observations.”

In addition to Lennon, the newly named craters are:

- Barney, for Natalie Clifford Barney (1876-1972), an American-French playwright, poet, and novelist.

- Berlioz, for Hector Berlioz (1803-1869), a French Romantic composer best known for his compositions Symphonie fantastique and Grande messe des morts.

- Calder, for Alexander Calder (1898-1976), an American sculptor best known as the originator of the mobile, a type of kinetic sculpture made with delicately balanced or suspended components that move in response to motor power or air currents.

- Capote, for Truman Capote (1924-1984), an American author whose short stories, novels, plays, and nonfiction include the novella Breakfast at Tiffany's and the true-crime novel In Cold Blood.

- Caruso, for Enrico Caruso (1873-1921), an Italian tenor who sang to great acclaim at the major opera houses of Europe and the Americas and appeared in a wide variety of roles from the Italian and French repertoires that ranged from the lyric to the dramatic.

- Ensor, for James Sidney Ensor (1860-1949), a Belgian painter and printmaker, considered an important influence on expressionism and surrealism.

- Giambologna, for Jean Boulogne Giambologna (1529-1608), a Dutch sculptor known for his marble and bronze statuary in a late Renaissance or Mannerist style.

- Remarque, for Erich Maria Remarque (1898-1970), a German author best known for his novel All Quiet on the Western Front, which depicted the horrors of war from the viewpoint of young German soldiers.

- Vieira da Silva, for Maria Elena Vieira da Silva (1908-1992), a Portuguese-born French painter of intricate, semiabstract compositions.

More information about the names of features on Mercury and the other objects in the Solar System can be found at the U.S. Geological Survey's planetary nomenclature web site:

For more information about Messenger Mission, visit:

Images (mentioned), Text, Credit: NASA.


Look out below – Design for Demise study aims to cut satellite reentry risk

ESA - Clean Space logo.

20 December 2013

Even in space, what goes up does sometimes come down – potentially endangering people on the ground. So ESA’s Clean Space initiative is commissioning a study on ‘Design for Demise’ techniques, aimed at reducing the risk of satellite fragments surviving atmospheric reentry.

Below about 600 km the vestigial atmosphere drags the sky clear of derelict satellites over a period of months or years. Friction between a fast-moving orbiting item and the air starts to slow it and pull it lower, at the same time generating heat.

GOCE reenters atmosphere

By the time an object reaches an altitude below 80 km, aerodynamic stresses should cause the item to break into smaller pieces, which in turn melt then vapourise, in the same way meteors burn up to become shooting stars.

But a surprising quantity of material actually survives its scorching plunge through the atmosphere. Dozens of items have been recovered over the years: while low-melt-rate materials such as aluminium do not generally make it, components made of titanium, steel and glass are more resilient.

The majority of such fragments fall unwitnessed into the oceans. Of the remaining land, only about a quarter is inhabited, so the odds of a human being struck per single fragment should be extremely low – the chance of any injury is truly minuscule compared to, say, a car accident. That has not stopped it happening, at least once: in 1997 lightweight mesh from a Delta II stage harmlessly hit the shoulder of Lottie Williams in Turley, Oklahoma, USA.

The hardiest spacecraft components are more prone to making it back. Fuel tanks, for instance, have variously landed in Thailand, Argentina, Saudi Arabia and the US state of Texas – the woman who found a 260 kg launcher tank on her farm just 50 metres from her home described it as looking like an ‘upside down rhinoceros’.

Debris fallen in Saudi Arabia

Since April 2008 all ESA satellites and launcher upper stages intended to be disposed of by atmospheric reentry at the end of their working lives must demonstrate that the risk from fragments surviving reentry to cause casualties on the ground is less than one in 10 000.

Ideally a mission would retain enough propellant to direct itself downwards in a controlled manner, increasing the likelihood of either total incineration or else steering down to an uninhabited area, but this is not always possible within the limited design margin of many spacecraft.

As an alternative, the multidisciplinary ‘Design for Demise’, D4D, approach is the intentional design of spacecraft systems and/or hardware to reduce the casualty risk on the ground, especially in the case of uncontrolled reentry.

So ESA’s Clean Space initiative has issued an invitation to tender for a new study to better quantify the satellite re-entry risk using various re-entry analysis tools, and consider how D4D can best reduce it.

Design for Demise technology roadmap (Click on the image for enlarge)

The study includes identifying which parts of a satellite pose the greatest risk and identify ways D4D can be applied to reduce it, from system to subsystem down to equipment level. These D4D techniques will also be applied to a pair of actual ESA missions, to assess their feasibility in practice.

Guidelines will be drawn up for applying D4D in future, and the technology developments needed for its use in future mission platforms will be outlined in a roadmap.

For more information check the invitation to tender package, accessible via ESA’s Electronic Mailing Invitation to Tender System (EMITS).

About Clean Space: 

What is Clean Space?:

Why is it needed?:

What are its objectives?:

Q & A on Clean Space:

Images, Text, Credits: ESA / Bill Chater / NASA Orbital Debris Program Office.

Best regards,

jeudi 19 décembre 2013

Astronauts Finalizing Spacewalk Preparations

ISS - Expedition 38 Mission patch / EVA - Extra Vehicular Activities patch.

Dec. 19, 2013

NASA astronauts Rick Mastracchio and Mike Hopkins and Japanese astronaut Koichi Wakata gathered together Thursday to review spacewalk procedures. Mastracchio and Hopkins will exit the station to replace a faulty pump module over a series of spacewalks. Wakata will operate the station’s robotic arm to maneuver the spacewalkers at the worksite.

The first spacewalk is scheduled for Saturday at 7:10 a.m. EDT when the spacewalkers will set up the worksite on the S1 truss. Monday’s spacewalk will include the removal of the old pump module and the installation of a spare pump module. If necessary a third spacewalk would occur on Christmas day to finalize the installation of the new pump module.

Station Spacewalks to Replace Pump Module

Video above: Lead U.S. Spacewalk Officer Allison Bolinger discusses the details of the three spacewalks the Expedition 38 crew will conduct to replace a faulty pump module on the International Space Station. Image Credit: NASA TV.

NASA Television will begin coverage of the spacewalks an hour before their 7:10 a.m. scheduled start times. The spacewalks are scheduled to last about six hours and 30 minutes. Shortly after the spacewalks conclude, mission controllers will participate in a briefing at Johnson Space Center to discuss the day’s activities.

A briefing was held Wednesday with International Space Station program manager Mike Suffredini, Flight Director Dina Contella and Lead Spacewalk Officer Allison Bolinger. The mission managers discussed how a faulty pump module forced the launch delay of the Cygnus resupply craft and led to the planning for the contingency spacewalks.

View spacewalk briefing graphics:

Read more about the news conference:

Read more about the Orbital 1 mission:

The astronauts are also preparing for the possibility of ammonia leaks during their spacewalk. The pump modules are filled with ammonia for cooling and leaks have occurred while disconnecting cables during previous repair spacewalks. If ammonia flakes get on a crew member’s suit, the spacewalkers would go through a series of decontamination steps before re-entering the space station.

Image above: Rick Mastracchio (foreground) checks U.S. spacesuits inside the Quest airlock. Image Credit: NASA TV.

In the Russian side of the space station, Commander Oleg Kotov and Sergey Ryazanskiy are preparing for a Dec. 27 pre-planned spacewalk. The cosmonauts with assistance from Flight Engineer Mikhail Tyurin resized their Orlan spacesuits, checked batteries and reviewed their translation paths to the external worksites.

The duo will install a foot restraint; install medium and high resolution cameras; jettison gear from a pair of external experiments; and install a new experiment as well as a payload boom on the Zvezda service module.

Kotov and Ryazanskiy also participated in a study that monitored their cardiovascular system. Tyurin later worked on the Russian radiation detection experiment Matryeshka that observes radiation absorption in a mannequin.

Read more about Matryeshka:

For more information about the Space Station (ISS), visit:

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


NASA's Asteroid Hunter Spacecraft Returns First Images after Reactivation

NASA - NEO WISE Mission logo.

Dec. 19, 2013

Probe Will Assist Agency in Search for Candidates to Explore

Image above: This image of a patch of sky in the constellation Pisces is among the first taken by the infrared cameras of NASA's NEOWISE spacecraft. Image Credit: NASA/JPL-Caltech.

NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), a spacecraft that made the most comprehensive survey to date of asteroids and comets, has returned its first set of test images in preparation for a renewed mission.

NEOWISE discovered more than 34,000 asteroids and characterized 158,000 throughout the solar system during its prime mission in 2010 and early 2011. It was reactivated in September following 31 months in hibernation to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NEOWISE also can assist in characterizing previously detected asteroids that could be considered potential targets for future exploration missions.

"NEOWISE not only gives us a better understanding of the asteroids and comets we study directly, but it will help us refine our concepts and mission operation plans for future, space-based near-Earth object cataloging missions," said Amy Mainzer, principal investigator for NEOWISE at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "The spacecraft is in excellent health, and the new images look just as good as they were before hibernation. Over the next weeks and months we will be gearing up our ground-based data processing and expect to get back into the asteroid hunting business, and acquire our first previously undiscovered space rock, in the next few months."

Some of the deep space images taken by the spacecraft include a previously detected asteroid named (872) Holda. With a diameter of 26 miles (42 kilometers), this asteroid orbits the sun between Mars and Jupiter in a region astronomers call the asteroid belt. The images tell researchers the quality of the spacecraft's observations is the same as during its primary mission.

The spacecraft uses a 16-inch (40-centimeter) telescope and infrared cameras to seek out and discover unknown NEOs and characterize their size, albedo or reflectivity, and thermal properties. Asteroids reflect, but do not emit visible light, so data collected with optical telescopes using visible light can be deceiving.

Infrared sensors, similar to the cameras on NEOWISE, are a powerful tool for discovering, cataloging and understanding the asteroid population. Some of the objects about which NEOWISE will be collecting data could become candidates for the agency's announced asteroid initiative.

NASA's initiative will be the first mission to identify, capture and relocate an asteroid. It represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet. The asteroid initiative brings together the best of NASA's science, technology and human exploration efforts to achieve President Obama's goal of sending humans to an asteroid by 2025.

WISE Reactivated to Hunt for Asteroids. Image Credit: NASA/JPL-Caltech

"It is important that we accumulate as much of this type of data as possible while the spacecraft remains a viable asset," said Lindley Johnson, NASA's NEOWISE program executive in Washington. "NEOWISE is an important element to enhance our ability to support the initiative."

NEOWISE began as WISE. The prime mission, which was launched in December 2009, was to scan the entire celestial sky in infrared light. WISE captured more than 2.7 million images in multiple infrared wavelengths and cataloged more than 747 million objects in space, ranging from galaxies faraway to asteroids and comets much closer to Earth. NASA turned off most of WISE's electronics when it completed its primary mission in February 2011.

Upon reactivation, the spacecraft was renamed NEOWISE with the goal of discovering and characterizing asteroids and comets whose orbits approach within 28 million miles (45 million kilometers) from Earth's path around the sun.

JPL manages the project for NASA's Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

Some of the first images taken during the spacecraft's checkout period are available at:

More information about NEOWISE is available online at:

For more information on the asteroid initiative, visit:

Images (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / DC Agle.


Liftoff for ESA’s billion-star surveyor

ARIANESPACE - GAIA launch poster / ESA - GAIA Mission patch.

19 December 2013

 Gaia liftoff

ESA’s Gaia mission blasted off this morning on a Soyuz rocket from Europe’s Spaceport in Kourou, French Guiana, on its exciting mission to study a billion suns.

Gaia is destined to create the most accurate map yet of the Milky Way. By making accurate measurements of the positions and motions of 1% of the total population of roughly 100 billion stars, it will answer questions about the origin and evolution of our home Galaxy.

Gaia launch

The Soyuz launcher, operated by Arianespace, lifted off at 09:12 GMT (10:12 CET). About ten minutes later, after separation of the first three stages, the Fregat upper stage ignited, delivering Gaia into a temporary parking orbit at an altitude of 175 km.

A second firing of the Fregat 11 minutes later took Gaia into its transfer orbit, followed by separation from the upper stage 42 minutes after liftoff. Ground telemetry and attitude control were established by controllers at ESA’s operations centre in Darmstadt, Germany, and the spacecraft began activating its systems.

The sunshield, which keeps Gaia at its working temperature and carries solar cells to power the satellite, was deployed in a 10-minute automatic sequence, completed around 88 minutes after launch.

Gaia is now en route towards an orbit around a gravitationally-stable virtual point in space called L2, some 1.5 million kilometres beyond Earth as seen from the Sun.

Tomorrow, engineers will command Gaia to perform the first of two critical thruster firings to ensure it is on the right trajectory towards its L2 home orbit. About 20 days after launch, the second critical burn will take place, inserting it into its operational orbit around L2.

Gaia: launch to orbit

A four-month commissioning phase will start on the way to L2, during which all of the systems and instruments will be turned on, checked and calibrated. Then Gaia will be ready to begin its five-year science mission.

Gaia’s sunshield will block heat and light from the Sun and Earth, providing the stable environment needed by its sophisticated instruments to make an extraordinarily sensitive and precise census of the Milky Way’s stars.

“Gaia promises to build on the legacy of ESA’s first star-mapping mission, Hipparcos, launched in 1989, to reveal the history of the galaxy in which we live,” says Jean-Jacques Dordain, ESA’s Director General.

“It is down to the expertise of Europe’s space industry and scientific community that this next-generation mission is now well and truly on its way to making ground-breaking discoveries about our Milky Way.”

Repeatedly scanning the sky, Gaia will observe each of the billion stars an average of 70 times each over the five years. It will measure the position and key physical properties of each star, including its brightness, temperature and chemical composition.

Gaia mapping the stars of the Milky Way

By taking advantage of the slight change in perspective that occurs as Gaia orbits the Sun during a year, it will measure the stars’ distances and, by watching them patiently over the whole mission, their motions across the sky.

The position, motion and properties of each star provide clues about its history, and Gaia’s huge census will allow scientists to piece together a ‘family tree’ for our home Galaxy.

The motions of the stars can be put into ‘rewind’ to learn more about where they came from and how the Milky Way was assembled over billions of years from the merging of smaller galaxies, and into ‘fast forward’ to learn more about its ultimate fate.

“Gaia represents a dream of astronomers throughout history, right back to the pioneering observations of the ancient Greek astronomer Hipparchus, who catalogued the relative positions of around a thousand stars with only naked-eye observations and simple geometry,” says Alvaro Giménez, ESA’s Director of Science and Robotic Exploration.

Deployment of Gaia's DSA

“Over 2000 years later, Gaia will not only produce an unrivalled stellar census, but along the way has the potential to uncover new asteroids, planets and dying stars.”

By comparing its repeated scans of the sky, Gaia will also discover tens of thousands of supernovas, the death cries of stars as they reach the end of their lives and explode. And slight periodic wobbles in the positions of some stars should reveal the presence of planets in orbit around them, as they tug the stars from side to side.

Gaia will also uncover new asteroids in our Solar System and refine the orbits of those already known, and will make precise tests of Einstein’s famous theory of General Relativity.

After five years, the data archive will exceed 1 Petabyte or 1 million Gigabytes, equivalent to about 200 000 DVD’s worth of data. The task of processing and analysing this mountain of data will fall to the Gaia Data Processing and Analysis Consortium, comprising more than 400 individuals across at scientific institutes across Europe.

“Where Hipparcos catalogued 120 000 stars, Gaia will survey almost 10 000 times as many and at roughly 40 times higher precision,” says Timo Prusti, ESA’s Gaia project scientist.

“Along with tens of thousands of other celestial and planetary objects, this vast treasure trove will give us a new view of our cosmic neighbourhood and its history, allowing us to explore the fundamental properties of our Solar System and the Milky Way, and our place in the wider Universe.”

“After years of hard work and determination of everyone involved in the mission, we are delighted to see our Gaia discovery machine on the road to L2, where we will continue the noble European tradition of star charting to decipher the history of the Milky Way,” adds Giuseppe Sarri, ESA’s Gaia project manager.

The spacecraft was designed and built by Astrium, with a core team composed out of Astrium France, Germany and the United Kingdom.

Related links:

Gaia overview:

Gaia factsheet:

Frequently asked questions:

Gaia brochure:

Hipparcos mission:

Images, Videos, Text, Credits: ESA / S. Corvaja / M. Pedoussaut / C. Carreau / ATG medialab; background: ESO / S. Brunier.


mercredi 18 décembre 2013

Expedition 38 Gets Ready for U.S. and Russian Spacewalks

ISS - Expedition 38 Mission patch.

Dec. 18, 2013

Flight Engineers Rick Mastracchio and Mike Hopkins continue preparing for a series of spacewalks to remove a failed pump module and install a spare pump module. NASA managers have planned for the first spacewalk to begin Saturday, the second on Monday and if necessary a third spacewalk on Christmas day.

Station Program Manager Mike Suffredini, Flight Director Dina Contella and lead spacewalk manager Allison Bolinger provided more details during a spacewalk briefing at Johnson Space Center.

Image above: Rick Mastracchio (left) and Mike Hopkins check a U.S. spacesuit inside the Quest airlock. Image Credit: NASA TV.

View spacewalk briefing graphics:

Read more about the news conference:

Mastracchio has six spacewalks to his credit with 38 hours and 30 minutes of experience working outside a spacecraft. This will be Hopkins first spacewalk.

The last time a spacewalk took place on Christmas day was in 1974 during the Skylab 4 mission. NASA astronauts Gerald Carr and William Pogue stepped outside the Skylab space station to retrieve film from a telescope and photograph Comet Kohoutek.

Image above: This computer graphic depicts a spacewalker attached to the Canadarm2 removing the starboard pump module. Image Credit: NASA TV.

Orbital Sciences is preparing to roll back their Antares rocket carrying the Cygnus commercial resupply craft back from the launch pad to its integration hangar. The Antares rolled out to the launch pad on Tuesday to protect for a planned Dec. 19 launch to deliver gear to the International Space Station. That launch has now slipped to no earlier than January so NASA can focus on replacing the pump module.

Read more about the Orbital 1 mission:

Commander Oleg Kotov and Flight Engineer Sergey Ryazanskiy are also preparing for a spacewalk. This is a pre-planned spacewalk scheduled for Dec. 27 outside the station’s Russian segment. The duo will install a foot restraint; install medium and high resolution cameras; jettison gear from a pair of external experiments; and install a new experiment as well as a payload boom on the Zvezda service module.

For more information about the International Space Station (ISS), visit:

Images (mentioned), Text, Credits:  NASA.


NASA's Deep Space Network: The Original 'Wireless Network' Turns 50

NASA patch.

Dec. 18, 2013

Dawn in the Apollo Valley

Image above: Beam Wave Guide antennas at Goldstone, known as the "Beam Waveguide Cluster." Each antenna is 111.5-feet (34-m) in diameter. Image Credit: NASA/JPL-Caltech.

NASA's Deep Space Network, the world's largest and most powerful communications system for "talking to" spacecraft, will reach a milestone on Dec. 24: the 50th anniversary of its official creation.

Over the past 50 years, antennas of the Deep Space Network (DSN) have communicated with just about every mission that has gone to the moon or beyond. The historic communiqués include "That's one small step for man. One giant leap for mankind"; numerous encounters with the outer planets of our solar system; images taken by rovers exploring Mars; and the data confirming that NASA's Voyager spacecraft had finally entered interstellar space.

The Deep Space Network has been so critical to so many missions over the decades, the network's team members like to use the phrase "Don't leave Earth without us."

From the very beginning of NASA's space program, it was clear that a simple, direct way to communicate with missions in deep space would be needed. For example, what is the purpose of sending a spacecraft to Mars if we can't receive data, images and other vital information from that spacecraft?

What is now known as the Deep Space Network first existed as just a few small antennas called the Deep Space Instrumentation Facility. The facility was originally operated by the U.S. Army in the 1950s and then later moved over to the jurisdiction of the newly created National Aeronautics and Space Administration (NASA).

On December 24, 1963, the Deep Space Instrumentation Facility officially morphed into the Deep Space Network and quickly became the de facto network for any planned missions into deep space. Three antenna complexes were established around the globe, spread out at roughly 120 degrees of longitude so that even as Earth rotated, spacecraft would always be above the horizon of at least one complex. While some of the communication facilities have moved over the decades, today the three complexes, which operate 24/7/365, are located in Canberra, Australia; Madrid, Spain; and Goldstone, Calif.

 Goldstone 70-Meter

Image above: Late night in the desert: Goldstone's 230-foot (70-meter) antenna tracks spacecraft day and night. This photograph was taken on Jan. 11, 2012. Image Credit: NASA/JPL-Caltech.

Space agencies in Europe, Japan and Russia have all relied on the Deep Space Network when planning and communicating with their own missions over the decades. The Deep Space Network has been used recently by India's first interplanetary probe, the Mars Orbiter Mission (MOM).

"Today, the DSN supports a fleet of more than 30 U.S. and international robotic space missions," said DSN Project Manager Al Bhanji of NASA's Jet Propulsion Laboratory, Pasadena, Calif., which manages the Deep Space Network.  "Without the DSN, we would never have been able to undertake voyages to Mercury and Venus, visit asteroids and comets, we'd never have seen the stunning images of robots on Mars, or close-up views of the majestic rings of Saturn."

In addition to allowing missions to upload and download data to and from dozens of spacecraft, the network helps navigators pinpoint spots for landings and conduct burns that place spacecraft into orbit around other planets, or fine-tune their trajectory. Currently, the list of spacecraft supported by the DSN includes NASA's Curiosity rover on Mars, the Spitzer Space Telescope, the Saturn explorer Cassini and the two Voyager spacecraft, which are more than 9.6 billion miles (15.5 billion kilometers) away from Earth.

 Goldstone 34-meter Beam Waveguide

Image above: Goldstone's 111.5-foot (34-meter) Beam Waveguide tracks a spacecraft as it comes into view. This photograph was taken on Jan. 11, 2012. Image Credit: NASA/JPL-Caltech.

The Deep Space Network is also instrumental in carrying out its own science investigations. For instance, the 230-foot (70-meter) antenna at Goldstone is capable of using its radar to "ping" the near-Earth asteroids to determine a highly accurate position and velocity, and scientists are then able to calculate trajectories the asteroids will take over the next 100 years or more. This is crucial for tracking asteroids that could potentially cause damage were they to impact Earth. If the asteroid is close enough, they can also use the radar to “image” the objects to determine its size, shape and rotation.

Additionally, by combining signals from the DSN antennas with other radio telescopes in an appropriate manner, one can create a "synthetic telescope" that's able to peer into the cores of active galaxies halfway across the observable universe. Likewise, the DSN can be used to probe interiors of planets in our own galaxy, study the solar wind and study gravitational physics.

The future of the Deep Space Network looks bright, with optical communications on the horizon to augment the traditional RF-technology (radio waves moving at the speed of light). Optical communications, when operational, will provide a dramatic increase in data return from science missions; the potential bandwidth carried by an optical communications laser beam is far greater than with traditional radio frequencies. In fact, the DSN team envisions the day, not so far off, when, in addition to returning photos of robotic wheel tracks in the dusty surface of Mars, they will be streaming video to a wide-eyed public as the first humans leave their own footprints on its surface.

"In 2063, when we celebrate the Deep Space Network's 100th anniversary, we can imagine that we might be recalling the amazing days when our antennas streamed high-res video as the first humans stepped onto the surface of Mars," said Al Bhanji. "Or that day when we discovered a new living 'Earth' orbiting a distant star."

Of course, no one knows if or when that day might come. But the DSN will likely play a paramount role in breaking the "Earth-shattering" news.

JPL, a division of the California Institute of Technology in Pasadena, manages the Deep Space Network for NASA. More information about the Deep Space Network is online at:

More information about NASA's Space Communications and Navigation program is at:

Images (mentioned), Text, Credits: NASA / Joshua Buck / JPL / David Israel.

Best regards,

Solar Dynamics Observatory Shows Sun's Rainbow of Wavelengths

NASA - Solar Dynamics Observatory (SDO) patch / NASA - ESA - SOHO Mission patch.

Dec. 18, 2013

This still image was taken from a new NASA movie of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, showing the wide range of wavelengths – invisible to the naked eye – that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors.

Jewel Box Sun

Video above: This movie, created by NASA's Scientific Visualization Studio at NASA's Goddard Space Flight Center in Greenbelt, Md., shows how features of the sun can appear dramatically different when viewed in different wavelengths. Image Credit: NASA's Goddard Space Flight Center.

Telescopes help distant objects appear bigger, but this is only one of their advantages. Telescopes can also collect light in ranges that our eyes alone cannot see, providing scientists ways of observing a whole host of material and processes that would otherwise be inaccessible.

A new NASA movie of the sun based on data from NASA's Solar Dynamics Observatory, or SDO, shows the wide range of wavelengths – invisible to the naked eye – that the telescope can view. SDO converts the wavelengths into an image humans can see, and the light is colorized into a rainbow of colors.

As the colors sweep around the sun in the movie, viewers should note how different the same area of the sun appears. This happens because each wavelength of light represents solar material at specific temperatures. Different wavelengths convey information about different components of the sun's surface and atmosphere, so scientists use them to paint a full picture of our constantly changing and varying star.

Yellow light of 5800 Angstroms, for example, generally emanates from material of about 10,000 degrees F (5700 degrees C), which represents the surface of the sun. Extreme ultraviolet light of 94 Angstroms, which is typically colorized in green in SDO images, comes from atoms that are about 11 million degrees F (6,300,000 degrees C) and is a good wavelength for looking at solar flares, which can reach such high temperatures. By examining pictures of the sun in a variety of wavelengths – as is done not only by SDO, but also by NASA's Interface Region Imaging Spectrograph, NASA's Solar Terrestrial Relations Observatory and the European Space Agency/NASA Solar and Heliospheric Observatory (SOHO)-- scientists can track how particles and heat move through the sun's atmosphere.

Related Links:

Why scientists observe the sun in different wavelengths:

About NASA’s heliosphysics fleet:

To download the video in high resolution and various formats:

More information:

NASA Solar Dynamics Observatory (SDO):

NASA SOHO Mission:

ESA SOHO Mission:

Image, Video (mentioned), Text, Credits: NASA Goddard Space Flight Center / Karen C. Fox.


mardi 17 décembre 2013

High-energy cosmic rays from solar flares



High-energy cosmic rays from solar flares during the period from November 10 to December 10, 2013 according spectrometers Pamela and Arina.

Magnetic Spectrometer Pamela and scintillation spectrometer Arina installed on board the satellite Resource-DK1 continue precision measurements of the charged component of cosmic rays and solar galactic nature.

Resource -DK1

In the past month (from November 10 to December 10), despite the large number of sunspots on the Sun almost did not happen powerful explosive processes (flares).

During this time, in experiments Arina and Pamela received time - intensity profiles of galactic and solar protons with energies of 45-100 MeV and 100 MeV - tens of GeV, respectively.

For clarity, Figure 1 shows the time profiles in the energy range 45 ÷ 55 MeV, 100 MeV and 145 ÷ 400 ÷ 540 MeV. Moments solar flares that occurred 10 and 19 November , marked by arrows, next to which specified event class (X1.1 and H1.0).

Figure 1. The intensity of galactic and solar cosmic rays in the period from November 10 until December 10, according spectrometers Pamela and Arina. Recess instruments related to the prevention of the spacecraft systems.

Thin horizontal lines in the figure shows the average flows in a quiet period of solar activity. During outbreaks spectrometers recorded appearance in near space high-energy solar protons with energies greater than 150 MeV. Other components of solar cosmic rays were detected.

ROSCOSMOS Press Release:

Image, Graphic, Text, Credits: Roscosmos press service / ROSCOSMOS / Translation: Aerospace.

Best regards,

NASA Postpones Orbital Launch, Sets Spacewalks to Repair Faulty Pump Module

Dec. 17, 2013

NASA managers are postponing the upcoming Orbital Sciences commercial cargo resupply mission to the International Space Station to proceed with a series of spacewalks to replace a faulty pump module on the space station.

Cygnus spacecraft

NASA Television will air a news briefing at 3 p.m. EST on Wednesday, Dec. 18 to preview the spacewalks.

Orbital Sciences' Cygnus spacecraft, atop its Antares rocket, now will launch no earlier than mid-January. The postponement of the Antares launch will allow ample time for the station crew to focus on repairing a faulty pump module that stopped working properly on Dec. 11.

Image above: Astronaut Rick Mastracchio posted this image of a spacesuit inside the Quest airlock Tuesday via his Twitter account, @AstroRM. Image Credit: NASA.

NASA currently plans for two Expedition 38 astronauts to venture outside the space station Dec. 21, 23 and 25. NASA astronauts Rick Mastracchio and Mike Hopkins will remove a pump module that has a failed valve. They will replace it with an existing spare that is stored on an external stowage platform. The pump is associated with one of the station's two external cooling loops, which circulate ammonia outside the station to keep both internal and external equipment cool. Each of the three spacewalks will begin at 7:10 a.m. and is scheduled to last six and a half hours. NASA TV coverage will begin at 6:15 a.m.

International Space Station (ISS)

Wednesday's spacewalks preview briefing will take place from NASA's Johnson Space Center in Houston. Reporters may attend the 3 p.m. briefing at Johnson and other participating NASA centers, or ask questions by calling the Johnson newsroom at 281-483-5111 no later than 2:45 p.m. Briefers will include:

- Michael Suffredini, International Space Station program manager

- Dina Contella, International Space Station flight director

- Allison Bolinger, lead spacewalk officer

View Tweet from @AstroRM:

For more information about the International Space Station, visit:

Images, Text, Credit: NASA / Orbital.

Best regards,

Artists at Work

NASA / ESA - Cassini Mission to Saturn patch.

Dec. 17, 2013

Saturn's moons create art on the canvas of Saturn's rings with gravity as their tool. Here Prometheus is seen sculpting the F ring while Daphnis (too small to discern in this image) raises waves on the edges of the Keeler gap.

Prometheus (53 miles, or 86 kilometers across) is just above image center while Daphnis (5 miles, or 8 kilometers across), although too small to see in its location in the Keeler gap just to the right of center, can be located by the waves it creates on the edges of the gap. Prometheus and stars have been brightened by a factor of 2 relative to the rest of the image to enhance their visibility. There are 20 stars visible in this image.

This view looks toward the unilluminated side of the rings from about 53 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 25, 2013.

Cassini spacecraft. Image Credits: NASA / ESA

The view was acquired at a distance of approximately 1.2 million miles (1.9 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 111  degrees. Image scale is 7 miles (11 kilometers) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit and The Cassini imaging team homepage is at .

Images, Text, Credit: NASA / JPL-Caltech / Space Science Institute.