samedi 10 septembre 2011

Two New Canadian Astronauts Certified












CSA-ASC logo.

Sept. 10, 2011

The Canadian Space Agency (CSA) is pleased to announce that its two new astronauts, Jeremy Hansen and David Saint-Jacques, have successfully completed their two-year basic training at NASA’s Johnson Space Center in Houston.

“Through diligence and hard work, Jeremy Hansen and David Saint-Jacques have earned the respect of their astronaut colleagues,” said the President of the CSA, Steve MacLean. “Our newest astronauts have come through with flying colours and are proud members of Canada’s Astronaut Corps.”

Now that basic training is complete, Hansen and Saint-Jacques have been assigned duties that will continue to broaden and perfect their skills, preparing them for future challenges. Both will work at the Johnson Space Centre. Jeremy Hansen will be assigned to the International Space Station Operations Branch and will assume the role of Crew Support Astronaut for Expedition 33/34, which includes Chris Hadfield’s mission. David Saint-Jacques has been assigned for duties within the Robotics Branch, which will include training and operations related to the European Robotic Arm. Both men are now eligible for selection for long-duration missions on the International Space Station.

Recruited by the Canadian Space Agency in May of 2009 through a national astronaut recruitment campaign, Jeremy Hansen and David Saint-Jacques have undertaken an intensive and rigorous training program which included:

- Attaining a thorough understanding of spacecraft and ISS systems, engineering, and science;

- acquiring techniques necessary to master operation of the ISS systems, including spacewalks (extravehicular activities), and manoeuvring the robotic arm;

- obtaining and enhancing skills and behaviors required of astronauts, including piloting an aircraft and taking part in survival training;

- improving their proficiency in the Russian language.

Their biographies are available on the CSA website:

Astronaut Jeremy Hansen

    Jeremy Hansen: http://www.asc-csa.gc.ca/eng/astronauts/biohansen.asp

 Astronaut David Saint-Jacques

    David Saint-Jacques: http://www.asc-csa.gc.ca/eng/astronauts/biosaintjacques.asp

Videos and pictures are available at the following addresses:

    Videos: ftp://ftp.asc-csa.gc.ca/users/Medias/pub/20110908_Training_DSJ_JH/

    Pictures: http://www.asc-csa.gc.ca/images/recherche/liste.aspx?search=Formation%20Nouveaux%20Astronautes&show=1&l=eng&format=1&g=event

Follow them on Twitter!:

@Astro_Jeremy: http://twitter.com/#!/Astro_Jeremy

@Astro_DavidS: http://twitter.com/#!/Astro_DavidS

Images, Text, Credit: CSA-ASC / NASA.

Cheers, Orbiter.ch

NASA Launches Mission To Study Moon From Crust To Core











NASA - GRAIL Mission patch.

Sept. 10, 2011

video
NASA GRAIL Spacecraft Launches on Lunar Mission

NASA's twin lunar Gravity Recovery and Interior Laboratory (GRAIL) spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:08 a.m. EDT Saturday to study the moon in unprecedented detail.

GRAIL liftoff

GRAIL-A is scheduled to reach the moon on New Year's Eve 2011, while GRAIL-B will arrive New Year's Day 2012. The two solar-powered spacecraft will fly in tandem orbits around the moon to measure its gravity field. GRAIL will answer longstanding questions about the moon and give scientists a better understanding of how Earth and other rocky planets in the solar system formed.

"If there was ever any doubt that Florida's Space Coast would continue to be open for business, that thought was drowned out by the roar of today's GRAIL launch," said NASA Administrator Charles Bolden. "GRAIL and many other exciting upcoming missions make clear that NASA is taking its next big leap into deep space exploration, and the space industry continues to provide the jobs and workers needed to support this critical effort."

The spacecraft were launched aboard a United Launch Alliance Delta II rocket. GRAIL mission controllers acquired a signal from GRAIL-A at 10:29 a.m. GRAIL-B's signal was eight minutes later. The telemetry downlinked from both spacecraft indicates they have deployed their solar panels and are operating as expected.

"Our GRAIL twins have Earth in their rearview mirrors and the moon in their sights," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "The mission team is ready to test, analyze and fine tune our spacecraft over the next three-and-a-half months on our journey to lunar orbit."

 Artist concept of GRAIL mission. Grail will fly twin spacecraft

The straight-line distance from Earth to the moon is approximately 250,000 miles (402,336 kilometers). NASA's Apollo moon crews needed approximately three days to cover that distance. However, each spacecraft will take approximately 3.5 months and cover more than 2.5 million miles (4 million kilometers) to arrive. This low-energy trajectory results in the longer travel time. The size of the launch vehicle allows more time for spacecraft check-out and time to update plans for lunar operations. The science collection phase for GRAIL is expected to last 82 days.

"Since the earliest humans looked skyward, they have been fascinated by the moon," said GRAIL principal investigator Maria Zuber from the Massachusetts Institute of Technology in Cambridge. "GRAIL will take lunar exploration to a new level, providing an unprecedented characterization of the moon's interior that will advance understanding of how the moon formed and evolved."

JPL manages the GRAIL mission. It is part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems in Denver built the spacecraft. Launch management for the mission is the responsibility of NASA's Launch Services Program at the Kennedy Space Center in Florida.

For more information about GRAIL, visit: http://www.nasa.gov/grail and http://grail.nasa.gov

Images, Videos, Text, Credit: NASA / NASA TV / MCC / KSC.

Greetings, Orbiter.ch

vendredi 9 septembre 2011

First Galileo satellite touches down in French Guiana

ESA - GALILEO logo.

9 September 2011

The first Galileo navigation satellite has arrived in Europe’s Spaceport in French Guiana, ready to begin preparations for launch on 20 October.

Packed within its protective, air-conditioned container, the satellite landed at Cayenne Rochambeau Airport aboard an Antonov aircraft at 06:45 local time on Wednesday 7 September, having departed from Thales Alenia Space Italy’s Rome facility, where it was built.

Galileo IOV FM2 satellite landed in French Guiana

A Thales and ESA team stood ready to receive it, having flown into French Guiana the previous week, along with all the testing and support equipment.

The team loaded the satellite container on a lorry for transport to the Guiana Space Centre, where it arrived at 10:00 local time and was moved into the preparation facility.

It stayed there overnight for the temperature to settle before it was taken out of its container the following morning.

Galileo IOV satellite

The satellite is due to be launched aboard a Soyuz ST-B vehicle on 20 October, together with a second Galileo that is now being readied for its own flight to French Guiana.

This will be the first launch of Russia’s workhorse Soyuz rocket from French Guiana. It will take place from a new facility 13 km northwest of the Ariane 5 launch site.

IOV satellites in orbit

Next year, the second pair of satellites will join them in orbits at 23 222 km altitude, proving the design of the Galileo system in advance of the other 26 satellites destined to join them.

The two Soyuz ST-B launchers – the more powerful variant of the two configurations of the upgraded Soyuz-ST launcher operated by Arianespace from the CSG – plus the reignitable Fregat-MT upper stages that will guide the satellites into their final orbits reached French Guiana from Russia in June.

Galileo team waits

Final assembly of the three-stage Soyuz ST-B and the fuelling of the Fregat-MT upper stage will start next week, well in time for the launch date.

Soyuz from French Guiana

October’s launch will be historic: the first Soyuz launch from a spaceport outside of Baikonur in Kazakhstan or Plesetsk in Russia.

Soyuz lift-off

French Guiana is much closer to the equator, so each launch will benefit from Earth’s spin, increasing the maximum payload into geostationary transfer orbit from 1.7 tonnes to 3 tonnes.

As a medium-class launcher, Soyuz will complement Ariane and Vega to increase the flexibility and competitiveness of Europe’s launcher family.

Each three-stage rocket will be assembled horizontally in the traditional Russian manner, transferred to the pad and moved to the vertical so that its payload can be added from above.

The new mobile gantry also protects the satellites and the vehicle from the humid tropical environment.

Galileo

Galileo IOV in orbit

These first four Galileo satellites, built by a consortium led by EADS Astrium Germany, will form the operational nucleus of the full Galileo satnav constellation.

video
 Galileo IOV Satellite

They combine the best atomic clock ever flown for navigation – accurate to one second in three million years – with a powerful transmitter to broadcast precise navigation data worldwide.

Online video:

Soyuz at Europe's Spaceport: http://multimedia.esa.int/Videos/2011/05/Fully-assembled-Soyuz-at-Europe-s-Space-Port

Related links:

TAS Italy: http://www.thalesgroup.com/Italy/

Arianespace: http://www.arianespace.com/index/index.asp

Roscosmos: http://www.roscosmos.ru/main.php?lang=en

Images, Video, Text, Credits: ESA / S. Corvaja / P. Carril / D. Ducros.

Best regards, Orbiter.ch

jeudi 8 septembre 2011

NASA Spacecraft Observes New Characteristics Of Solar Flares












NASA - Solar Dynamics Observatory (SDO) patch.

Sep. 08, 2011

NASA's Solar Dynamics Observatory, or SDO, has provided scientists new information about solar flares indicating an increase in strength and longevity that is more than previously thought.

SDO Spots a Late Phase in Solar Flares

video

Video above: A compilation of solar data from various instruments on SDO recording a flare on May 5, 2010. The images on top show the initial magnetic loops of the flare, and a delayed brightening of additional magnetic loops above the originals showing the late phase flare. Along the bottom, graphs from EVE show the extreme ultraviolet light peaking both in time with the main flare and the late phase flare. Credit: NASA / SDO / Tom Woods.

Solar flares are intense bursts of radiation from the release of magnetic energy associated with sunspots. They are the solar system's largest explosive events and are seen as bright areas on the sun. Their energy can reach Earth's atmosphere and affect operations of Earth-orbiting communication and navigation satellites.

Using SDO's Extreme ultraviolet Variability Experiment (EVE) instrument, scientists have observed that radiation from solar flares continue for up to five hours beyond the main phase. The new data also show the total energy from this extended phase of the solar flare's peak sometimes has more energy than the initial event.

"Previous observations considered a few seconds or minutes to be the normal part of the flare process," said Lika Guhathakurta, lead program scientist for NASA's Living with a Star Program at the agency's Headquarters in Washington. "This new data will increase our understanding of flare physics and the consequences in near-Earth space where many scientific and commercial satellites reside."
On Nov. 3, 2010, SDO observed a solar flare. If scientists only had measured the effects of the flare as it initially happened, they would have underestimated the amount of energy shooting into Earth's atmosphere by 70 percent. SDO's new observations provide a much more accurate estimation of the total energy solar flares put into Earth's environment.

video

Video above: On May 5, 2010, shortly after the Solar Dynamics Observatory (SDO) began normal operation, the sun erupted with numerous coronal loops and flares. Many of these showed a previously unseen "late phase flare" appearing minutes to hours after the main flare. Credit: NASA / SDO.

"For decades, our standard for flares has been to watch the X-rays as they happen and see when they peak," said Tom Woods, a space scientist at the University of Colorado in Boulder and principal author on a paper in Wednesday's online edition of Astrophysical Journal. "But we were seeing peaks that didn't correspond to the X-rays."

During the course of a year, the team used EVE to map each wavelength of light as it strengthened, peaked, and diminished over time. EVE records data every 10 seconds and has observed many flares. Previous instruments only measured every 90 minutes or didn't look at all wavelengths simultaneously as SDO can.


Graphic above: Instead of a conventional picture, the EUV variability Experiment (EVE) on board SDO produces graphs like this, called spectra, that show the total intensity of any given extreme ultraviolet (EUV) wavelength of light coming off of the sun. This image shows a single moment from May 5, 2010. The height of each vertical line represents how much energy is present in that particular wavelength. Spectra like this can measure energy from the sun more comprehensively than instruments that can only “see” a single wavelength. Credit: NASA / SDO / EVE.

To compliment the EVE graphical data, scientists used images from another SDO instrument, the Advanced Imaging Assembly (AIA). Analysis of these images showed the main flare eruption and its extended phase in the form of magnetic field lines called coronal loops that appeared far above the original eruption site. These extra loops were longer and became brighter later than the loops from the main flare and also were physically set apart from those of the main flare.

Because this previously unrealized extra source of energy from flares also is impacting Earth's atmosphere, Woods and his colleagues are studying how the late phase flares can influence space weather. Space weather caused by solar flares can affect communication and navigation systems, satellite drag and the decay of orbital debris.

SDO was launched on Feb. 11, 2010. The spacecraft is the most advanced spacecraft ever designed to study the sun and its dynamic behavior. SDO provides images 10 times clearer than high definition television and more comprehensive science data faster than any solar observing spacecraft in history.

EVE was built by the Laboratory for Atmospheric and Space Physics at the University of Colorado. AIA was built by Lockheed Martin Solar and Astrophysics Laboratory in Palo Alto, Calif.

NASA's Goddard Space Flight Center in Greenbelt, Md., built, operates and manages the SDO spacecraft for NASA's Science Mission Directorate in Washington. SDO is the first mission of NASA's Living with a Star Program, or LWS. The goal of LWS is to develop the scientific understanding necessary to address those aspects of the connected sun-Earth system that directly affect our lives and society.

For more information and images, visit: http://www.nasa.gov/sunearth

For more information about the SDO mission and instruments, visit: http://www.nasa.gov/sdo

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

Greetings, Orbiter.ch

mercredi 7 septembre 2011

The number of space debris reached a "critical point"










Space Junk.

Sep. 7, 2011

A waste weightless, floating in space and encasing our beloved planet. This is the ecological disaster of decades of space exploration. In a report released this week, U.S. scientists are sounding the alarm: the number of debris floating in space has reached a "critical point", which threatens more and more on satellites and astronauts.

video

Video above: Space Debris Video, from AIAA's 1st Biennnial Congressional Aerospace Policy Retreat, which took place 18 March 2011.

"Space is becoming more dangerous for spacecraft and astronauts," says this report Donald Kessler, former head of NASA and the president of a commission to study the issue of orbital debris. "NASA needs to find the best way to tackle all the problems caused by meteoroids and orbital debris that pose risks on men and the missions of space robots," said he.

Prohibition of debris pick another country

NASA has recorded 22 000 debris and estimated millions of those numbers too small to be recorded. Among the debris, at least 500 000 were between 1 and 10 cm in diameter, and can cause damage. Computer projections show that the number has reached a "critical point" which they will collide and create new debris, further increasing the risk of damaging the spacecraft, according to the National Research Council, an organization independent research which oversees the committee.

Space junk a conceptual artwork representing defunct satellites, failed missions, and shrapnel orbiting Earth

In 2007, China has further increased the number of debris by testing anti-satellite missile that had sprayed a weather satellite in 150 000 pieces. Or do the cleaning is not only expensive but also extremely complicated. Because the U.S. has no right under international law, to collect objects in space from other countries. "The Cold War is over but the issue of satellite technology is sensitive," says Vice-Chairman of the Committee, George Gleghorn.

The report of the Committee, 160 pages, recommends that NASA seeks the help of the State Department to address "the economic, technological, political and legal".

Current status of the launchers:

Since the sixties (early in the Mercury Program), NASA to recover some of the elements of its launch vehicles, mainly for technical and scientific expertise, a concern for ecological recovery emerged in the early 80 with the space shuttle with all elements of the launcher's back, the main tank burns in large part during its atmospheric re-entry., it was part of the basic concept, making the launch "less expensive" and more environmentally friendly "recycling" everything.

Recovery of Gemini V Booster


Image above: The external fuel tank of the orbiter falls back to earth after detaching from the space shuttle Discovery in July 2005. Engineers are analysing these photos as part of the extensive imagery data being gathered to understand falling debris during the shuttle's launch.

Space Shuttle Solid Rocket Booster Recovery


This image above provided by NASA show unidentified possible small debris recorded by digital still camera by Shuttle crew.
 
With the future launch vehicle and Ares Orion capsule, the whole is recovering.


The Russian Space Station Mir burns up as it enters the Earth's atmosphere over Nadi, Fiji, in March 2001. After 15 years of service in outer space, Mir made its re-entry to Earth.

In Russia, Soyuz, Proton, only the boosters and the first stage are generally recovered by local scrap dealers.

KAZAKHSTAN - The fiery wreck of a rocket booster after crashing

The movie "Space Tourists" illustrates the impact of the Russian space program on the environment, if you find from your rental company movie, rent it! (See Trailer below).

video
Space Tourists

KAZAKHSTAN - Scrap-metal dealers wait for a rocket to crash

KAZAKHSTAN - The fiery wreck of a rocket after crashing

At the ESA, since the generation Ariane 5 boosters are recovered.

 Ariane 5 solid rocket booster recovery

Over 90% of the debris fall into the oceans. Regarding the satellite end of life and other debris, the problem is their uncontrolled fall for some models.

The Automated Transfer Vehicle (ATV) is designed as the Progress cargo, to burn at its re-entry.

 ATV re-entry

Examples of falling debris in all different parts of the world:


Australian farmer James Stirton stands next to a ball of twisted metal, purported to be fallen space junk, on his farm in southwestern Queensland in March 2008. Stirton found the giant ball, which he believes is space junk from a rocket used to launch communications satellites.


Theodore Solomons sits next to the metal ball that he saw fall from the sky on a farm close to Worcester, about 150 kilometres outside of Cape Town, south Africa in April 2000. A second metal ball dropped out of the sky the following day on a farm approximately 50 kilometres outside of Cape Town. Astronomers said the balls, which were white-hot when they landed, could be parts of a decaying satellite.


A US Customs official inspects the largest piece of wreckage from the downed Skylab at the San Francisco International Airport, California, in July 1979. The one-ton piece wreckage was found in Australia.


ALTAI, Russia - Villagers collect scrap from a crashed spacecraft, surrounded by thousands of white butterflies, 2000. Environmentalists fear for the region's future due to toxic rocket fuel.


ALTAI, Russia - Dead cows lie on a cliff, 2000. Locals say that whole herds of cattle and sheep regularly die because rocket fuel poisons the soil.


A main propellant tank of a Delta 2 launch vehicle which landed in Georgetown, Texas, on Jan. 22, 1997.

Space debris fell in Saudi Arabia

How to Track Space Junk Online: http://www.wired.com/wiredscience/2009/03/howtojunk/

AIAA's 1st Biennnial Congressional Aerospace Policy Retreat: http://www.aiaa.org/content.cfm?pageid=896

Images, Videos, Text, Credits: NASA / ESA / ROSCOSMOS PAO / AFP / Le Monde.fr / BBC / AIAA / AGI / Orbiter.ch.

Best regards, Orbiter.ch

Baikonur is mounted a measuring station for the flight control interplanetary probe "Phobos-Grunt"












Roscosmos logo.

09/07/2011

At Baikonur continues preparations for the upcoming launch of the rocket "Zenit-2M" with interplanetary station "Phobos-Grunt" in November 2011.

In order to monitor and control system in the first two weeks on the 23rd floor space center (measuring station "Saturn") specialists TsENKI and OAO "Russian Space Systems" is the deployment of telemetry complex "spectrum of the X-Men." Decided to create a new station with an antenna complex "courier", previously used to work for launch communications satellites, "Lightning." Antenna diameter is only 12 meters, but the complex equipment and powerful modern highly sensitive technique allows to control the flight of interplanetary probes at a distance of several million kilometers.


Within two weeks, experts expect to complete installation of equipment, and then begin testing the transmitters, receivers and computer equipment industry. The culmination of a complex telemetry, "Spectrum-X" will be its commissioning.


Launch of "Phobos-Grunt" capabilities of the new station will not be exhausted, it will be used for flight control of other Russian interplanetary probes.

Images, Text, Credits: Press-service of Russian Federal Space Agency (Roscosmos PAO) and KC "Southern" / Translation: Orbiter.ch.

Greetings, Orbiter.ch

The “Scinence” special edition on “HAYABUSA” research reports was published











JAXA - HAYABUSA Mission patch.

August 26, 2011 (JST)

The Japan Aerospace Exploration Agency (JAXA) has been engaged in collecting and categorizing particles in the sampler container (*1), which was brought back by the instrumental module of the asteroid exploration spacecraft "HAYABUSA" from asteroid "Itokawa."

As part of this effort, JAXA has been conducting the initial analysis (*2) of particles identified as rocky using scanning electron microscope (SEM) observations, which were collected from sample catcher compartment "A."

As a part of achievements of the initial analysis, six HAYABUSA research reports were published in the "Science Magazine" dated August 26, 2011. In addition, the cover of this magazine features these achievements.

This is also epoch-making news since the special issues that the asteroid explorer "HAYABUSA's" neighborhood observation on asteroid "Itokawa" in June 2006, the solar observation satellite "HINODE" in December 2007 and "KAGUYA" in February 2009.

The titles of the research reports in Science magazine are as follows:

1) Itokawa dust particles: A direct link between S-type asteroids and ordinary chondrites
2) Oxygen Isotopic Compositions of Asteroidal Materials Returned from Itokawa by the Hayabusa Mission
3) Neutron Activation Analysis of a Particle Returned from Asteroid Itokawa
4) Three-dimensional structure of Hayabusa sample: Origin and evolution of Itokawa regolith
5) Incipient space weathering observed on the surface of Itokawa dust
6) Irradiation history of Itokawa regolith material deduced from noble gases in the Hayabusa samples

*1 The HAYABUSA sampler container consists of 2 compartments that are called Sample Catcher A and B.

*2 "Initial analysis" means the analysis of typical particles to obtain information necessary for categorizing (identification, classification and numbering) as a part of curation activity (*3).

*3 "Curation activity" means the retrieval of particles, preservation, categorizing and allocation and their necessary analysis.

Science Magazine 26 August 2011 : Cover


A small rocky particle, 150 microns in size, brought buck from asteroid "Itokawa " by the asteroid exploration spacecraft "HAYABUSA."

Mission website:

Science: http://www.sciencemag.org/magazine.dtl
Asteroid Explorer "HAYABUSA" (MUSES-C): http://www.jaxa.jp/projects/sat/muses_c/index_e.html
Tohoku University: http://www.tohoku.ac.jp/english/
KEK / Tohoku University: http://www.kek.jp/intra-e/press/2011/082613/
Hokkaido University: http://www.hokudai.ac.jp/en/
Tokyo Metropolitan University: http://www.tmu.ac.jp/english/index.html
Osaka University: http://www.osaka-u.ac.jp/en/index.html
The University of Tokyo: http://www.u-tokyo.ac.jp/index_e.html

Appendix: Research Reports Titles with Outlines

Author: Tomoki Nakamura (Tohoku University) et al.
Title: Itokawa dust particles: A direct link between S-type asteroids and ordinary chondrites
Abstract: The Hayabusa spacecraft successfully recovered dust particles from the surface of near-Earth asteroid 25143 Itokawa. Synchrotron-radiation X-ray diffraction and transmission and scanning electron microscope analyses indicate that the mineralogy and mineral chemistry of the Itokawa dust particles are identical to those of thermally metamorphosed LL chondrites, consistent with spectroscopic observations made from Earth and by the Hayabusa Spacecraft. Our results directly demonstrate that ordinary chondrites, the most abundant meteorites found on the Earth, come from S-type asteroids. Mineral chemistry indicates that the majority of regolith surface particles suffered long-term thermal annealing and subsequent impact shock, suggesting that Itokawa is an asteroid made of reassembled pieces of the interior portions of a once larger asteroid.

Author: Hisayoshi Yurimoto (Hokkaido University) et al.
Title:Oxygen Isotopic Compositions of Asteroidal Materials Returned from Itokawa by the Hayabusa Mission
Abstract:Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We have measured by secondary ion mass spectrometry oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in 16O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. We have the first direct oxygen-isotope link between chondrites and their parent asteroid.

Author: Mitsuru Ebihara (Tokyo Metropolitan University) et al.
Title:Neutron Activation Analysis of a Particle Returned from Asteroid Itokawa
Abstract:A single grain (~3 μg) returned by the Hayabusa spacecraft was analyzed by neutron activation analysis. This grain is mainly composed of olivine with minor amounts of plagioclase, troilite and metal. Our results establish that the Itokawa sample has similar chemical characteristics (Fe/Sc and Ni/Co ratios) to chondrite, confirming that this grain is extraterrestrial in origin and has primitive chemical compositions. Estimated Ir/Ni and Ir/Co ratios for metal in the Itokawa samples are about five times lower than CI values. A similar depletion of Ir was observed in chondrules metals of ordinary chondrites. These metals must have condensed from the nebular where refractory siderophile elements already condensed and were segregated.

Author: Akira Tsuchiyama (Osaka University) et al.
Title:Three-dimensional structures of Hayabusa sample: Origin and evolution of Itokawa regolith
Abstract:Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Thee-dimensional (3D) structures of these particles examined by X-ray microtomography give information for comparison with meteorites and about regolith formation. Modal abundances of minerals, bulk density (3.4 g/cm3), and the 3D textures indicate a mixture of equilibrated and less-equilibrated LL chondrite materials. No particles showing melting were observed. 3D shape features of these particles (size and shape distributions, and the presence of particles with rounded edges) are different from the lunar regolith and suggest that they were formed by meteoroid impacts on the asteroid surface, and eroded by seismic-induced grain motion in the smooth terrain. The results indicate that the returned samples are a good representation of the surface materials on Itokawa.

Author: Takaaki Noguchi (Ibaraki University) et al.
Title:Incipient space weathering observed on the surface of Itokawa dust
Abstract:The reflectance spectra of the most abundant meteorites, ordinary chondrites, are different from the abundant S-type asteroids. This discrepancy hasbeen thought to be due to space weathering, which is an alteration of surfaces of airless bodies exposed to the space environment. Here we report evidence of space weathering on particles returned from the S-type asteroid Itokawa by the Hayabusa spacecraft. Surface modification was found in 5 out of 10 particles, which varies depending on mineral species. Sulfur-bearing Fe-rich nanoparticles (npFe) exist in a thin (5-15 nm) surface layer on olivine, low-Ca pyroxene, and plagioclase, suggestive of vapor deposition. Sulfur-free npFe exist deeper inside (<60 nm) ferromagnesian silicates. Their texture suggests formation by metamictization and in-situ reduction of Fe2+.

Author: Keisuke Nagao (The University of Tokyo) et al.
Title:Irradiation history of Itokawa regolith material deduced from noble gases in the Hayabusa samples
Abstract: Noble gas isotopes were measured in three rocky grains from asteroid Itokawa to elucidate a history of irradiation from cosmic rays and solar wind on its surface. Large amounts of solar helium (He), neon (Ne), and argon (Ar) trapped in various depths in the grains were observed, which can be explained by multiple implantations of solar wind particles into the grains, combined with preferential He loss caused by frictional wear of space-weathered rims on the grains. Short residence time of less than 8 million years was implied for the grains by an estimate on cosmic-ray.produced 21Ne. Our results suggest that Itokawa is continuously losing its surface materials into space at a rate of tens of centimeters per million years. The lifetime of Itokawa should be much shorter than the age of our solar system.

Images, Text, Credit: Japan Aerospace Exploration Agency (JAXA).

Greetings, Orbiter.ch

Young Stars Take a Turn in the Spotlight












ESO - European Southern Observatory logo.

7 September 2011

 The star cluster NGC 2100 in the Large Magellanic Cloud

ESO’s New Technology Telescope (NTT) has captured a striking image of the open cluster NGC 2100. This brilliant star cluster is around 15 million years old, and located in the Large Magellanic Cloud, a nearby satellite galaxy of the Milky Way. The cluster is surrounded by glowing gas from the nearby Tarantula Nebula.

Observers often overlook NGC 2100 because of its close proximity to the impressive Tarantula Nebula (eso0650) and the super star cluster RMC 136 (eso1030). The glowing gas of the Tarantula Nebula even tries to steal the limelight in this image — the bright colours here are the nebula’s outskirts. This new picture was created from exposures through several different colour filters using the EMMI instrument [1] on the New Technology Telescope at ESO’s La Silla Observatory in Chile. The stars are shown in their natural colours, while light from glowing ionised hydrogen (shown here in red) and oxygen (shown in blue) is overlaid.

The star cluster NGC 2100 in the constellation of Dorado

The colours that appear in nebulae depend on the temperatures of the stars lighting them up. The hot young stars in the Tarantula Nebula, which lie in the super star cluster RMC 136, are above and to the right of this image, and are powerful enough to cause oxygen to glow [2] showing up as blue nebulosity in this picture. Below NGC 2100 the red glow indicates either that the outer reaches of the influence of the hot stars of RMC 136 has been reached, or that cooler, and older, stars, that are only able to excite hydrogen are the dominant influence in this region. The stars that make up NGC 2100 are older and less energetic, and hence have little or no nebulosity associated with them.

The star cluster NGC 2100 in context

Star clusters are groups of stars that formed around the same time from a single cloud of gas and dust. The stars with the most mass tend to form in the centre of the cluster, while those with less mass dominate the outer regions. This, along with the greater number of stars concentrated in the centre, makes the middle of the cluster brighter than the outer regions.

video
Zooming in on the star cluster NGC 2100 in the Large Magellanic Cloud

NGC 2100 is an open cluster, which means its stars are relatively loosely bound by gravity. These clusters have a lifespan measured in tens or hundreds of millions of years, as they eventually disperse through gravitational interaction with other bodies. Globular clusters, which look similar to the untrained eye, contain many more older stars and are much more tightly bound, and so have far longer lifespans: many globular clusters have been measured to be almost as old as the Universe itself. So while NGC 2100 might be older than its neighbours in the Large Magellanic Cloud, it is still a youngster by the standards of star clusters.

Data for this image of the under-appreciated young cluster were selected from the depths of ESO’s data archives by Hidden Treasures entrant David Roma as part of the astrophotography competition held by ESO in 2010 [3].

Notes:

[1] EMMI stands for ESO Multi Mode Instrument. It is both a camera for imaging and a spectrograph.

[2] Most of the glow from oxygen comes from oxygen atoms that have lost two electrons. This strong emission is very common in nebulae but was mysterious to early astronomical spectroscopists and was initially thought to be coming from a new element given the name Nebulium.

[3] ESO’s Hidden Treasures 2010 competition gave amateur astronomers the opportunity to search through ESO’s vast archives of astronomical data, hoping to find a well-hidden gem that needed polishing by the entrants. To find out more about Hidden Treasures, visit http://www.eso.org/public/outreach/hiddentreasures/.

More information:

ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. 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 a 40-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

    Photos of the NTT and La Silla Observatory: http://www.eso.org/public/images/archive/category/lasilla/

    David Roma’s Hidden Treasures image: http://www.flickr.com/photos/55944793@N02/5178599427/in/pool-1562202@N22/

Images, Text, Credit: ESO / IAU and Sky & Telescope / Video: ESO / R. Gendler / N. Risinger (skysurvey.org). Music: John Dyson (from the album Moonwind).

Cheers, Orbiter.ch

mardi 6 septembre 2011

NASA Spacecraft Images Offer Sharper Views Of Apollo Landing Sites














NASA - Lunar Reconnaissance Orbiter (LRO) patch / NASA - Apollo Program logo.

Sept. 6, 2011

NASA's Lunar Reconnaissance Orbiter (LRO) captured the sharpest images ever taken from space of the Apollo 12, 14 and 17 landing sites. Images show the twists and turns of the paths made when the astronauts explored the lunar surface.

At the Apollo 17 site, the tracks laid down by the lunar rover are clearly visible, along with the last foot trails left on the moon. The images also show where the astronauts placed some of the scientific instruments that provided the first insight into the moon's environment and interior.

"We can retrace the astronauts' steps with greater clarity to see where they took lunar samples," said Noah Petro, a lunar geologist at NASA's Goddard Space Flight Center in Greenbelt, Md., who is a member of the LRO project science team.

Apollo 17, LRO image released today (image 1)

Apollo 17, LRO image released in 2009 (image 2)

The first image was released today; the second image is a zoom-in on an LRO image released in 2009. LRO was moved into a lower orbit to capture the new image. The images do not line up perfectly because of differences in lighting conditions, angle of the LRO Camera, and other variables. Image brightness and contrast have been altered to highlight surface details. (Credit: NASA's Goddard Space Flight Center/ASU).

All three images show distinct trails left in the moon's thin soil when the astronauts exited the lunar modules and explored on foot. In the Apollo 17 image, the foot trails, including the last path made on the moon by humans, are easily distinguished from the dual tracks left by the lunar rover, which remains parked east of the lander.

Apollo 17 area by LRO

"The new low-altitude Narrow Angle Camera images sharpen our view of the moon's surface," said Arizona State University researcher Mark Robinson, principal investigator for the Lunar Reconnaissance Orbiter Camera (LROC). "A great example is the sharpness of the rover tracks at the Apollo 17 site. In previous images the rover tracks were visible, but now they are sharp parallel lines on the surface."

At each site, trails also run to the west of the landers, where the astronauts placed the Apollo Lunar Surface Experiments Package (ALSEP) to monitor the moon's environment and interior. This equipment was a key part of every Apollo mission.

It provided the first insights into the moon's internal structure, measurements of the lunar surface pressure and the composition of its atmosphere. Apollo 11 carried a simpler version of the science package.

 Apollo 12, LRO image released today (image 1)

Apollo 12, LRO image released in 2009 (image 2)

The first image was released today; the second image is a zoom-in on an LRO image released in 2009. LRO was moved into a lower orbit to capture the new image. The images do not line up perfectly because of differences in lighting conditions, angle of the LRO Camera, and other variables. Image brightness and contrast have been altered to highlight surface details. (Credit: NASA's Goddard Space Flight Center/ASU).

One of the details that shows up is a bright L-shape in the Apollo 12 image. It marks the locations of cables running from ALSEP's central station to two of its instruments. Although the cables are much too small for direct viewing, they show up because they reflect light very well.
 Apollo 12 area by LRO

The higher resolution of these images is possible because of adjustments made to LRO's orbit, which is slightly oval-shaped or elliptical. "Without changing the average altitude, we made the orbit more elliptical, so the lowest part of the orbit is on the sunlit side of the moon," said Goddard's John Keller, deputy LRO project scientist. "This put LRO in a perfect position to take these new pictures of the surface."


Image above: The paths left by astronauts Alan Shepard and Edgar Mitchell on both Apollo 14 moon walks are visible in this image. (At the end of the second moon walk, Shepard famously hit two golf balls.) The descent stage of the lunar module Antares is also visible. (Credit: NASA's Goddard Space Flight Center/ASU).

The maneuver lowered LRO from its usual altitude of approximately 31 miles (50 kilometers) to an altitude that dipped as low as nearly 13 miles (21 kilometers) as it passed over the moon's surface. The spacecraft has remained in this orbit for 28 days, long enough for the moon to completely rotate. This allows full coverage of the surface by LROC's Wide Angle Camera. The cycle ends today when the spacecraft will be returned to its 31-mile orbit.

"These images remind us of our fantastic Apollo history and beckon us to continue to move forward in exploration of our solar system," said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington.

video

Video above: NASA Goddard's Dr. Noah Petro discusses the significance of the new Apollo images from LRO. (Credit: Chris Smith, NASA's Goddard Space Flight Center).

LRO was built and managed by Goddard. Initial research was funded by the Exploration Systems Mission Directorate at NASA Headquarters. In September 2010, after a one-year successful exploration mission, the mission turned its attention from exploration objectives to scientific research in NASA's Science Mission Directorate.

To learn more about LRO, visit: http://www.nasa.gov/lro

Related Links:

Apollo Revisited: More images of Apollo sites from LRO: http://www.nasa.gov/mission_pages/apollo/revisited/index.html

Additional imagery related to this story from ASU's LROC website: http://lroc.sese.asu.edu/news/?archives/454-Skimming-the-Moon.html

Images, (mentioned), Video (mentioned), Text, Credit: NASA's Goddard Space Flight Center / Nancy Neal-Jones / Steve Cole.

Greetings, Orbiter.ch