jeudi 6 septembre 2012

NASA Mars Rover Curiosity Begins Arm-Work Phase

NASA - Mars Science Laboratory (MSL) patch.

07 Sep 2012

Image above: The left eye of the Mast Camera (Mastcam) on NASA's Mars rover Curiosity took this image of the camera on the rover's arm, the Mars Hand Lens Imager (MAHLI), during the 30th Martian day, or sol, of the rover's mission on Mars (Sept. 5, 2012). Image credit: NASA/JPL-Caltech/MSSS.

After driving more than a football field's length since landing, NASA's Mars rover Curiosity is spending several days preparing for full use of the tools on its arm.

Curiosity extended its robotic arm Wednesday in the first of six to 10 consecutive days of planned activities to test the 7-foot (2.1-meter) arm and the tools it manipulates.

"We will be putting the arm through a range of motions and placing it at important 'teach points' that were established during Earth testing, such as the positions for putting sample material into the inlet ports for analytical instruments," said Daniel Limonadi of NASA's Jet Propulsion Laboratory in Pasadena, Calif., lead systems engineer for Curiosity's surface sampling and science system. "These activities are important to get a better understanding for how the arm functions after the long cruise to Mars and in the different temperature and gravity of Mars, compared to earlier testing on Earth."

Since the Mars Science Laboratory spacecraft placed Curiosity inside Mars' Gale Crater on Aug. 5 PDT (Aug. 6 EDT), the rover has driven a total of 358 feet (109 meters). The drives have brought it about one-fourth of the way from the landing site, named Bradbury Landing, to a location selected as the mission's first major science destination, Glenelg.

"We knew at some point we were going to need to stop and take a week or so for these characterization activities," said JPL's Michael Watkins, Curiosity mission manager. "For these checkouts, we need to turn to a particular angle in relation to the sun and on flat ground. We could see before the latest drive that this looked like a perfect spot to start these activities."

Curiosity's Robotic Arm

Video above: This engineering drawing shows the location of the arm on NASA's Curiosity rover, in addition to the arm's turret, which holds two instruments and three tools. The arm places and holds turret-mounted tools on rock and soil targets. It also manipulates the sample-processing mechanisms on the 66-pound (30-kilogram) turret.

The arm has five degrees of freedom of movement provided by rotary actuators known as the shoulder azimuth joint, shoulder elevation joint, elbow joint, wrist joint and turret joint. Video Credit: NASA/JPL-Caltech.

The work at the current location will prepare Curiosity and the team for using the arm to place two of the science instruments onto rock and soil targets. In addition, the activities represent the first steps in preparing to scoop soil, drill into rocks, process collected samples and deliver samples into analytical instruments.

Checkouts in the next several days will include using the turret's Mars Hand Lens Imager to observe its calibration target and the Canadian-built Alpha Particle X-Ray Spectrometer to read what chemical elements are present in the instrument's calibration target.

"We're still learning how to use the rover. It's such a complex machine -- the learning curve is steep," said JPL's Joy Crisp, deputy project scientist for the Mars Science Laboratory Project, which built and operates Curiosity.

Curiosity's Work Bench

Image above: This engineering drawing shows various components needed to support tools at the end of the arm on NASA's Curiosity rover, including: calibration targets for helping instruments set their baseline levels; spare bits for the rover's drill; a sample "playground" that gives the rover a place to drop off processed samples for observation by the APXS and MAHLI instruments; three inlet covers, which protect the SAM and CheMin instruments from atmospheric dust; and a set of five "organic check material" canisters, which provide a known chemical makeup blank that can be drilled and provided to SAM as a calibration material. Image credit: NASA/JPL-Caltech.

After the arm characterization activities at the current site, Curiosity will proceed for a few weeks eastward toward Glenelg. The science team selected that area as likely to offer a good target for Curiosity's first analysis of powder collected by drilling into a rock.

"We're getting through a big set of characterization activities that will allow us to give more decision-making authority to the science team," said Richard Cook, Mars Science Laboratory project manager at JPL.

Curiosity is one month into a two-year prime mission on Mars. It will use 10 science instruments to assess whether the selected study area ever has offered environmental conditions favorable for microbial life. JPL manages the mission for NASA's Science Mission Directorate in Washington.

More information about Curiosity is online at: and .

Follow the mission on Facebook at: and on Twitter at: .

Latest images:

Curiosity gallery:

Curiosity videos:

Images (mentioned), Video (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / Guy Webster / D.C. Agle.


Rover Completes Longest Drive Yet

NASA - Mars Science Laboratory (MSL) patch.

06 Sep 2012

Curiosity completed a drive of 100 feet (30.5 meters) during the mission's Sol 29, on Sept. 4, 2012, traveling southeastward with a dogleg move partway through the drive to skirt some sand. This was the mission's longest drive so far and brought total driving distance to 358 feet (109 meters).

This artist concept features NASA's Mars Science Laboratory Curiosity rover, a mobile robot for investigating Mars' past or present ability to sustain microbial life. Image credit: NASA/JPL-Caltech.

A Navigation Camera image with a wheel track from the Sol 29 drive is in the mission's collection of raw images, at .

Curiosity continues to work in good health. Sol 29, in Mars local mean solar time at Gale Crater, ended at 2:37 a.m. Sept. 5, PDT.

The Mars Science Laboratory spacecraft is one month into a two-year mission to investigate whether conditions have been favorable for microbial life and preserving clues in the rocks about possible past life.

For more information about NASA's Curiosity mission, visit: and .

Image (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / DC Agle / Guy Webster.


A Family Portrait of Galaxies

ESA - Hubble Space logo.

6 September 2012

 Hubble image of Arp 116

Two very different galaxies feature in this family portrait taken by the NASA/ESA Hubble Space Telescope, together forming a peculiar galaxy pair called Arp 116. The image shows the dramatic differences in size, structure and colour between spiral and elliptical galaxies.

Arp 116 is composed of a giant elliptical galaxy known as Messier 60, and a much smaller spiral galaxy, NGC 4647.

Being a typical elliptical galaxy, Messier 60 on its own may not be very exciting to look at, but together with its adjacent spiral friend, the pair becomes a rather interesting feature in the night sky.

Ground-based image of Arp 116 and its surroundings

Messier 60 is very bright — the third brightest in the Virgo cluster of galaxies, a collection of more than 1300 galaxies. It is noticeably larger than its neighbour, and has a far higher mass of stars. M 60, like other elliptical galaxies, has a golden colour because of the many old, cool and red stars in it. NGC 4647, on the other had, has many young and hot stars that glow blue, giving the galaxy a noticeably different hue.

Astronomers have long tried to determine whether these two galaxies are actually interacting. Although they overlap as seen from Earth, there is no clear evidence of vigorous new star formation. In interacting pairs of galaxies, the mutual gravitational pull that the galaxies exert on each other typically disrupts gas clouds, much like tides on Earth are caused by the Moon’s gravity. This disruption can cause gas clouds to collapse, forming a sudden burst of new stars.

Zoom into Arp 116

Although this does not appear to have happened in Arp 116, studies of very detailed Hubble images suggest the onset of some tidal interaction between the two.

Regardless of whether they are actually close enough to be interacting, however, the two galaxies are certainly near neighbours. This means we see the two galaxies at the same scale, making Hubble’s family portrait a textbook example of how giant elliptical galaxies differ in size, structure and colour from their smaller spiral brethren.

Surprisingly Messier 60 was discovered independently by three different astronomers in 1779. Johann Gottfried Koehler of Dresden first spotted it on 11 April that year while observing a comet, the Italian Barnabus Oriani noticed it a day later, and the French Charles Messier saw it on 15 April. Charles Messier then listed the galaxy in the Messier Catalogue.

Pan across Arp 116

Having photographed the galaxy pair with the 5-metre Hale telescope, US astronomer Halton Arp included it in his Atlas of Peculiar Galaxies, published in 1966. The catalogue contains images of 338 “peculiar galaxies” — merging, overlapping and interacting galaxies.

This large image is a mosaic of images in visible and infrared light taken by Hubble’s Advanced Camera for Surveys and Wide Field and Planetary Camera 2.

Hubble in orbit


    Images of Hubble:

    NASA release:

Images, Text, Credit: NASA, ESA / Digitized Sky Survey 2 (Acknowledgement: Davide De Martin) / Videos: NASA, ESA, A. Fujii, Digitized Sky Survey 2. Music: R. Vreeland (

Best regards,

Hadley Crater provides deep insight into martian geology

ESA - Mars Express Mission patch.

6 September 2012

 Hadley Crater

Recently engaged in providing support to the successful landing of NASA’s Mars Science Laboratory's Curiosity rover, ESA’s Mars Express has now returned to its primary mission of studying the diverse geology and atmosphere of the 'Red Planet' from orbit.

Earlier this year, the spacecraft observed the 120 km wide Hadley Crater, providing a tantalising insight into the martian crust. The images show multiple subsequent impacts within the main crater wall, reaching depths of up to 2600 m below the surrounding surface. 

Hadley Crater perspective view

This region imaged on 9 April 2012 by the High Resolution Stereo Camera on Mars Express shows the crater which lies to the west of the Al-Qahira Vallis in the transition zone between the old southern highlands and the younger northern lowlands.

Hadley is named after the British lawyer and meteorologist George Hadley (1685-1768) whose name was also given to the ‘Hadley cell’, a circulation system in the Earth’s atmosphere, which transports heat and moisture from the tropics up to higher latitudes.

The images show that Hadley Crater was struck multiple times by large asteroids and/or comets after its initial formation and subsequent infilling with lava and sediments.

Some of these later impacts have also been partly buried, with subtle hints of a number of crater rims to the west (top), and wrinkle ridges to the north (right side) of the main crater floor as shown in the first image at the top of the page.

Hadley Crater in context

Again, in the first image (top of the page), the southern (left) side, the crater appears shallower than the opposite side. This difference can be explained by an erosion process known as mass wasting. This is where surface material moves down a slope under the force of gravity.

Mass wasting can be initially started by a range of processes including earthquakes, erosion at the base of the slope, ice splitting the rocks or water being introduced into the slope material, In this case there is no clear indication which process caused it, or over what timescales this may have occurred.

Hadley Crater perspective view

Of particular interest to scientists studying the geology of Mars are the ejecta of the smaller craters within Hadley. Two of them, one to the west (top), and the deepest one in the middle of the first image, show evidence for volatiles, possibly water ice beneath the surface.

With the impact that forms the craters, this ice would mix with surrounding materials to form a kind of 'mud', which would then spread over the surface as ejecta.

Topographical view of Hadley crater

Scientists believe these volatiles which were excavated by the impacts, may indicate the presence of ice to a depth of around hundreds of metres, this being the difference in depth between the surface and the depths of the two craters.

This deep view into the martian crust within the walls of Hadley Crater provides scientists an insight into the history of Mars. A history which rovers like those currently on the Red Planet and others which follow will doubtless continue to investigate.

3D anaglyph view of Hadley crater

Related links:

Mars Express:

High Resolution Stereo Camera:

Behind the lens:

Mars Express in depth:

Frequently asked questions:

Mars Express blog:

Mars Webcam:

Images, Text, Credits: ESA / DLR / FU Berlin (G. Neukum) / NASA / MGS  / MOLA Science Team.


mercredi 5 septembre 2012

ISS spacewalk - Williams, Hoshide Complete MBSU Installation

ISS - Expedition 32 Mission patch.

September 5, 2012

Flight Engineers Suni Williams and Aki Hoshide completed their second spacewalk in less than a week at 1:34 p.m. EDT Wednesday. They completed the installation of a Main Bus Switching Unit (MBSU) that was hampered last week by a possible misalignment and damaged threads where a bolt must be placed. They also installed a camera on the International Space Station’s robotic arm, Canadarm2.

Image above: Spacewalkers Aki Hoshide and Suni Williams work outside the International Space Station. Credit: NASA TV.

A post-spacewalk briefing at Johnson Space Center is scheduled for no earlier than 2:45 p.m.

Watch NASA TV:

MBSU cleaning tools that were used during installation. Credit: NASA TV

Flight Engineer Joe Acaba operated the Canadarm2 and monitored the spacewalkers from inside the International Space Station. Hoshide rode the Canadarm2 attached to a portable foot restraint to the MBSU worksite.

Wednesday’s spacewalk lasted 6 hours and 28 minutes.

Spacewalkers Aki Hoshide work outside the International Space Station. Credit: NASA TV

View EVA briefing graphics from Aug. 14:

Last week’s spacewalk lasted eight hours and 17 minutes making it the third longest in U.S. spaceflight history. It was originally scheduled for 6.5 hours before mission controllers and the astronauts struggled to install the MBSU.

Read more about the Aug. 30 spacewalk:

View post-EVA briefing graphics from Aug. 30:

Suni Williams surpassed Peggy Whitson during Wednesday’s excursion for total cumulative spacewalk time by a female astronaut. Whitson worked outside for 39 hours and 46 minutes over the course of six spacewalks. Williams has conducted six spacewalks for a total of 44 hours and 2 minutes.

Read more about Expedition 32:

Expedition 32 Mission Summary (4.7 MB PDF):

Images, Text, Credits: NASA / NASA TV.


A Cluster with a Secret

ESO - European Southern Observatory logo.

5 September 2012

 The globular star cluster Messier 4

A new image from ESO’s La Silla Observatory in Chile shows the spectacular globular star cluster Messier 4. This ball of tens of thousands of ancient stars is one of the closest and most studied of the globular clusters and recent work has revealed that one of its stars has strange and unexpected properties, apparently possessing the secret of eternal youth.

The globular star cluster Messier 4 in the constellation of Scorpius

The Milky Way galaxy is orbited by more than 150 globular star clusters that date back to the distant past of the Universe (eso1141). One of the closest to the Earth is the cluster Messier 4 (also known as NGC 6121) in the constellation of Scorpius (The Scorpion). This bright object can be easily seen in binoculars, close to the bright red star Antares, and a small amateur telescope can show some of its constituent stars.

Wide-field view of the sky around the globular star cluster Messier 4

This new image of the cluster from the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory reveals many more of the cluster’s tens of thousands of stars and shows the cluster against the rich background of the Milky Way.

NASA/ESA Hubble Space Telescope image of the centre of Messier 4

Astronomers have also studied many of the stars in the cluster individually using instruments on ESO’s Very Large Telescope. By splitting the light from the stars up into its component colours they can work out their chemical composition and ages.

The globular star cluster Messier 4: and the location of a curious star

New results for the stars in Messier 4 have been surprising. The stars in globular clusters are old and hence not expected to be rich in the heavier chemical elements [1]. This is what is found, but one of the stars in a recent survey was also found to have much more of the rare light element lithium than expected. The source of this lithium is mysterious. Normally this element is gradually destroyed over the billions of years of a star's life, but this one star amongst thousands seems to have the secret of eternal youth. It has either somehow managed to retain its original lithium, or it has found a way to enrich itself with freshly made lithium.

Zooming in on the globular star cluster Messier 4

This WFI image gives a wide view of the cluster and its rich surroundings. A complementary and more detailed view of just the central region from the orbiting NASA/ESA Hubble Space Telescope was also released this week as part of the Hubble Picture of the Week series.

Panning across the globular star cluster Messier 4


[1] Most of the chemical elements heavier than helium are created in stars and dispersed into the interstellar medium at the end of their lives. This enriched material then forms the building blocks of future stellar generations. As a result very old stars, such as those in globular star clusters, which formed before significant enrichment had occurred, are found to have lower abundances of the heavier elements when compared to stars, such as the Sun, that formed later.

More information:

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning 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”.

    A research paper about the surprisingly lithium-rich star in Messier 4 (Monaco et al.):

    Photos of the VLT:

    Photos of the MPG/ESO 2.2-metre Telescope:

    Other photos taken with the MPG/ESO 2.2-metre Telescope:

    Photos of La Silla:

ESO / Acknowledgement: ESO Imaging Survey / IAU and Sky & Telescope / Digitized Sky Survey 2, A cknowledgment: Davide De Martin / ESA / Hubble & NASA / Videos: ESO / ESA /NASA / Digitized Sky Survey 2 / Nick Risinger ( / Acknowledgement: ESO Imaging Survey/ Music: Disasterpeace.

Best regards,

lundi 3 septembre 2012

Peek-a-blue Moon

Eumetsat - Meteosat Second Generation (MSG-3) logo.

3 September 2012

 Earth and Moon

Europe’s latest weather satellite got a glimpse of the Moon before our celestial neighbour disappeared from view behind Earth on Friday. Since its launch two months ago, MSG-3 has been working well and is on its way to entering service.

The image shows the second full Moon of the month – known as a ‘blue’ Moon – just before it disappeared from the MSG-3 satellite’s sight behind the southern hemisphere.

Brazil’s eastern coast along the South Atlantic Ocean is also visible, with clouds forming over the water.

The image was captured by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) instrument at 11:20 GMT.

The imager scans Earth’s surface and atmosphere every 15 minutes in 12 different wavelengths to track cloud development and measure temperatures.

Launched on 5 July, the third Meteosat Second Generation satellite is in a six-month commissioning phase by Eumetsat, the European Organisation for Exploitation of Meteorological Satellites.

This includes checking that the imaging service works fully and delivers high-quality products for weather forecasting.

Meteosat Second Generation (MSG-3)

ESA developed the satellite in close cooperation with Eumetsat, and was responsible for initial operations after launch. It was then handed over to Eumetsat on 16 July.

The first satellite in the series, MSG-1 – also known as Meteosat-8 – was launched in 2002. MSG-2 followed three years later. Both have continued the legacy of the operational meteorological satellites that started with Meteosat-1 in 1977.

The MSGs offer more spectral channels and are sensing Earth more frequently and at a higher resolution than their predecessors. 

Related links:

Meteosat Second Generation:

Images , Text, Credits: ESA / Eumetsat.


A smart way to impact the Moon

ESA - SMART-1 Mission patch.

3 September 2012

 SMART-1 crash scene

Image above: SMART-1 ended its journey in the Lake of Excellence at 34ºS / 46ºW at 05:42:22 GMT on 3 September 2006. The approximate impact site is indicated in the image, which is part of a much larger mosaic created during SMART-1’s final orbits of the Moon. The images were obtained by the Advanced Moon Imaging Experiment (AMIE).

On the morning of 3 September 2006, a brief flash illuminated the Moon’s ‘Lake of Excellence’ as ESA’s SMART-1 mission met its fate on the dusty surface.

Launched in 2003, SMART-1 was the first European spacecraft to travel to and orbit the Moon.

Short for Small Missions for Advanced Research in Technology, SMART-1 used ion propulsion to journey to the Moon, tested new techniques in communications and navigation, and carried a battery of miniaturised scientific instruments.

It completed a comprehensive inventory of key chemical elements in the lunar surface, mapped impact craters, studied the volcanic and tectonic processes that shaped the Moon, and investigated sites for future exploration.

Satellite SMART-1 wallpaper. Image credit: ESA / AOES Medialab

Like many of its predecessors doomed by the laws of gravity, SMART-1 was always destined to meet its fate on the lunar surface.

Six years ago today, the satellite was deliberately crashed at the site circled in this image, which lies within a region known as the Lake of Excellence, located at mid-southern latitudes on the lunar near-side.

The image is part of a larger mosaic taken during the spacecraft’s final orbits of the Moon and captures a variety of geological features: volcanic plains, hills and impact craters of varying size.

SMART-1 likely struck the side of a hill at a low angle of 5–10 degrees and a speed of about 2 km/s.

Observatories around the world saw the resulting impact flash and cloud of dust thrown up by the impact.

Estimates suggest that SMART-1 left a crater 3–10 m wide and perhaps a metre deep. Using new high-resolution data, scientists hope to locate the impact crater. 

Related links:

SMART-1 larger mosaic images taken during the spacecraft’s final orbits of the Moon:


Advanced Moon micro-Imager Experiment (AMIE):

More about SMART-1 impact ground observations:

Images, Text, Credits: ESA / AOES Medialab / Space-X (Space Exploration Institute).

Best regards,