vendredi 2 mai 2014

Hubble View: A Hungry Starburst Galaxy

ESA - Hubble Space Telescope patch.

May 2, 2014

This new Hubble picture is the sharpest ever image of the core of spiral galaxy Messier 61. Taken using the High Resolution Channel of Hubble's Advanced Camera for Surveys, the central part of the galaxy is shown in striking detail.

Also known as NGC 4303, this galaxy is roughly 100,000 light-years across, comparable in size to our galaxy, the Milky Way. Both Messier 61 and our home galaxy belong to a group of galaxies known as the Virgo Supercluster in the constellation of Virgo (The Virgin) — a group of galaxy clusters containing up to 2,000 spiral and elliptical galaxies in total.

Messier 61 is a type of galaxy known as a starburst galaxy. Starburst galaxies experience an incredibly high rate of star formation, hungrily using up their reservoir of gas in a very short period of time (in astronomical terms). But this is not the only activity going on within the galaxy; deep at its heart there is thought to be a supermassive black hole that is violently spewing out radiation.

Despite its inclusion in the Messier Catalogue, Messier 61 was actually discovered by Italian astronomer Barnabus Oriani in 1779. Charles Messier also noticed this galaxy on the very same day as Oriani, but mistook it for a passing comet — the comet of 1779.

For images and more information about Hubble, visit: and 

Image, Text, Credits: ESA/Hubble & NAS, Acknowledgement: Det58.

Best regards,

Tracking particles faster at the LHC

CERN - European Organization for Nuclear Research logo.

May 2, 2014

ATLAS high-energy collisions at the Large Hadron Collider

A new trigger system will expand what ATLAS scientists can look for during high-energy collisions at the Large Hadron Collider.

For its next big performance, the Large Hadron Collider will restart in 2015 with twice its previous collision energy and a much higher rate of particle collisions per second.

Scientists have been scurrying to prepare their detectors for the new particle onslaught. As part of this preparation, a group that includes physicists from laboratories and universities in the Chicago area are designing a new system that will allow them to examine collisions faster than ever before.

When the Large Hadron Collider is running, billions of particle collisions occur every second. Of these, only a few are the kind of direct hits that scientists are looking for. These high-impact collisions convert large amounts of pure energy into mass, temporarily producing new particles such as Higgs bosons for physicists to study.

In order to separate these rare and interesting events from the billions of less exciting collisions, scientists create complex processing systems called triggers. Trigger systems look for the most interesting collisions and record them for further analysis. Now, an international collaboration of scientists on the ATLAS experiment are creating a unique upgrade to their trigger system called the Fast Tracker, which will revolutionize how they sort collision events. Currently, scientists at Fermilab, Argonne, the University of Illinois and the University of Chicago are manufacturing and testing prototypes of several component parts of the ATLAS Fast Tracker.

Fermilab’s CDF detector, which ran from 1985 to 2011, employed a system based on the same idea as the Fast Tracker, says University of Chicago postdoctoral fellow John Alison. However, thanks to advancements in technology over the past two decades, the new ATLAS system is about 10,000 times more powerful.

Alison says this new component of the trigger system will help the ATLAS detector handle the upgraded LHC. It could even allow scientists to see things they might have missed during its first run.

“In a sense, if you change the trigger in a collider experiment, you really change the whole experiment,” Alison says. “By changing how the trigger system decides which events are interesting, we will be able to ask different questions and look for things we might have been blind to before. The next run of the LHC will be very interesting.”

The higher rate of particle collisions per second planned for the next and future runs of the LHC requires a more powerful, more discerning trigger system, says Yasuyuki Okumura, a postdoctoral fellow at the University of Chicago and Fermilab.

"Maintaining an efficient trigger in a high luminosity environment is incredibly challenging,” Okumura says. "The technology used in the system will help lead future high-energy hadron collider experiments.”

The ATLAS trigger system used during the first run of the LHC weeded out uninteresting collisions in three stages. Stage one looked for interesting particles in the detector, such as high-energy muons or photons, or large clusters of energy in the calorimeters. If a set of collisions passed this first stage of the trigger system, then all the data from that batch was passed to the second trigger. The second and third triggers then ran series of algorithms to whittle down the collision data even more.

The Fast Tracker will be an intermediate step between the first and second triggers. Using parallel processing and a series of custom-designed computer chips, the Fast Tracker will do something never before possible: simultaneously reconstruct the tracks of all of the particles in every region of the detector.

The coming runs of the LHC could shed light on some of the lingering questions left by our best understanding of the nature of matter, the Standard Model of particle physics, Alison says.

“The real interest in run two of the LHC is the unknown,” Alison says. “The Fast Tracker will give us more flexibility to save the interesting signals that we don't yet know we're interested in."


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 20 Member States.

Related links:

Large Hadron Colllider (LHC):

LHC experiments ATLAS:

LHC experiments CMS:


For more information about European Organization for Nuclear Research (CERN), visit:

Image, Text, Credits: CERN / Claudia Marcelloni / Sarah Charley.


Active Dune Field on Mars

NASA - Mars Reconnaissance Orbiter (MRO) patch.

May 2, 2014

Active Dune Field on Mars

Nili Patera is one of the most active dune fields on Mars. As such, it is continuously monitored with the HiRISE (High Resolution Imaging Science Experiment) camera, a science instrument aboard NASA's Mars Reconnaissance Orbiter, with a new image acquired about every six weeks.

By monitoring the sand dune changes, we can determine how winds vary seasonally and year-to-year. This observation is one of the more recent Nili images, acquired on March 1, 2014. Compared to an image acquired on Nov. 22, 2012, changes are obvious. The ripples on the dunes have moved, as well some of the dune boundaries, such as the one at upper left. New landslides on the central dune's lee face are apparent.

Nili images, acquired on Nov. 22, 2012

Such changes, in just 16 months (and finer scale changes have been seen in just a couple of weeks), demonstrate the effectiveness of wind in modifying the Martian landscape.

 The Active Dunes of Nili Patera

HiRISE is one of six instruments on NASA's Mars Reconnaissance Orbiter. The University of Arizona, Tucson, operates the orbiter's HiRISE camera, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for the NASA Science Mission Directorate, Washington.

For more information about Mars Reconnaissance Orbiter (MRO) mission, visit: and

Images, Video, Text, Credits: NASA/JPL-Caltech/Univ. of Arizona/Caption: Nathan Bridges.


jeudi 1 mai 2014

Target on Mars Looks Good for NASA Rover Drilling

NASA - Mars Science Laboratory (MSL) patch.

April 30, 2014

Image above: NASA's Curiosity Mars rover completed a shallow "mini drill" test April 29, 2014, in preparation for full-depth drilling at a rock target called "Windjana." This image from Curiosity's Mars Hand Lens Imager shows the hole resulting from the test, 0.63 inch across and about 0.8 inch deep. Image Credit: NASA/JPL-Caltech/MSSS.

NASA's Curiosity Mars rover performed a "mini-drill" operation Tuesday, April 29, on the rock target under consideration for the mission's third sample-collection drilling. This preparatory activity produced a hole about eight-tenths of an inch (2 centimeters) deep, as planned, in the target called "Windjana." The rover team plans to decide whether to proceed with deeper drilling of this rock in coming days.

The team operating NASA's Curiosity Mars rover plans to proceed in coming days with the third-ever drilling into a rock on Mars to collect a sample for analysis.

The rover used several tools to examine the candidate site over the weekend, including a wire-bristle brush -- the Dust Removal Tool -- to clear away dust from a patch on the rock. The target slab of sandstone has been given the informal name "Windjana," after a gorge in Western Australia.

"In the brushed spot, we can see that the rock is fine-grained, its true color is much grayer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures," said Curiosity science team member Melissa Rice of the California Institute of Technology, Pasadena. "All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock."

Animation above: This two-step animation shows before and after views of a patch of sandstone scrubbed with the Dust Removal Tool, a wire-bristle brush, on NASA's Curiosity Mars rover. Both images were taken April 26, 2014, by the Mars Hand Lens Imager on Curiosity's arm. The target rock is called "Windjana." Animation Credit: NASA/JPL-Caltech/MSSS.

Before Curiosity drills deeply enough for collection of rock-powder sample, plans call for a preparatory "mini-drill" operation on the target, as a further check for readiness.

Curiosity's hammering drill collects powdered sample material from the interior of a rock, and then the rover prepares and delivers portions of the sample to laboratory instruments onboard. The first two Martian rocks drilled and analyzed this way were mudstone slabs neighboring each other in Yellowknife Bay, about 2.5 miles (4 kilometers) northeast of the rover's current location at a waypoint called "The Kimberley." Those two rocks yielded evidence last year of an ancient lakebed environment with key chemical elements and a chemical energy source that provided conditions billions of years ago favorable for microbial life.

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

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

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


Cassini Spies the Ice-Giant Planet Uranus

NASA - Cassini International logo.

May 01, 2014

Blue Orb on the Horizon

Image above: This view from NASA's Cassini spacecraft features a blue planet, but unlike the view from July 19, 2013 (PIA17172) that featured our home planet, this blue orb is Uranus, imaged by Cassini for the first time. Credit: NASA/JPL-Caltech/Space Science Institute.

NASA's Cassini spacecraft has captured its first-ever image of the pale blue ice-giant planet Uranus in the distance beyond Saturn's rings.

The robotic spacecraft briefly turned its gaze away from the ringed beauty of Saturn on April 11, 2014, to observe the distant planet, which is the seventh planet from the sun.

The image is available at:

The planets Uranus and Neptune are sometimes referred to as "ice giants" to distinguish them from their larger siblings, Jupiter and Saturn, the classic "gas giants." The moniker derives from the fact that a comparatively large part of the planets' composition consists of water, ammonia and methane, which are typically frozen as ices in the cold depths of the outer solar system. Jupiter and Saturn are made almost entirely of hydrogen and helium, with smaller percentages of these ices.

When this view was obtained, Uranus was nearly on the opposite side of the sun as seen from Saturn, at a distance of approximately 28.6 astronomical units from Cassini and Saturn. An astronomical unit is the average distance from Earth to the sun, equal to 93 million miles (150 million kilometers). At their closest - once during each Saturn orbit of nearly 30 years - the two planets approach to within about 10 astronomical units of each other.

In addition to its aesthetic appeal, Cassini's view of Uranus also serves a practical purpose. Scientists working on several of Cassini's science investigations expect that they will be able to use images and spectra from these observations to help calibrate their own instruments.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

More information about Cassini is available at the following sites: and and

NASA / JPL / Preston Dyches / Space Science Institute / Steve Mullins.

Ganymede May Harbor 'Club Sandwich' of Oceans and Ice

NASA - Galileo Mission patch.

May 01, 2014

Image above: This artist's concept of Jupiter's moon Ganymede, the largest moon in the solar system, illustrates the "club sandwich" model of its interior oceans. Image credit: NASA/JPL-Caltech.

The largest moon in our solar system, a companion to Jupiter named Ganymede, might have ice and oceans stacked up in several layers like a club sandwich, according to new NASA-funded research that models the moon's makeup.

Previously, the moon was thought to harbor a thick ocean sandwiched between just two layers of ice, one on top and one on bottom.

"Ganymede's ocean might be organized like a Dagwood sandwich," said Steve Vance of NASA's Jet Propulsion Laboratory in Pasadena, Calif., explaining the moon's resemblance to the "Blondie" cartoon character's multi-tiered sandwiches. The study, led by Vance, provides new theoretical evidence for the team's "club sandwich" model, first proposed last year. The research appears in the journal Planetary and Space Science.

The results support the idea that primitive life might have possibly arisen on the icy moon. Scientists say that places where water and rock interact are important for the development of life; for example, it's possible life began on Earth in bubbling vents on our sea floor. Prior to the new study, Ganymede's rocky sea bottom was thought to be coated with ice, not liquid -- a problem for the emergence of life. The "club sandwich" findings suggest otherwise: the first layer on top of the rocky core might be salty water.

"This is good news for Ganymede," said Vance. "Its ocean is huge, with enormous pressures, so it was thought that dense ice had to form at the bottom of the ocean. When we added salts to our models, we came up with liquids dense enough to sink to the sea floor."

NASA scientists first suspected an ocean in Ganymede in the 1970s, based on models of the large moon, which is bigger than Mercury. In the 1990s, NASA's Galileo mission flew by Ganymede, confirming the moon's ocean, and showing it extends to depths of hundreds of miles. The spacecraft also found evidence for salty seas, likely containing the salt magnesium sulfate.

Image above: Annotated Image of Possible 'Moonwich' of Ice and Oceans on Ganymede (Artist's Concept). Image credit: NASA/JPL-Caltech.

Previous models of Ganymede's oceans assumed that salt didn't change the properties of liquid very much with pressure. Vance and his team showed, through laboratory experiments, how much salt really increases the density of liquids under the extreme conditions inside Ganymede and similar moons. It may seem strange that salt can make the ocean denser, but you can see for yourself how this works by adding plain old table salt to a glass of water. Rather than increasing in volume, the liquid shrinks and becomes denser. This is because the salt ions attract water molecules.

The models get more complicated when the different forms of ice are taken into account. The ice that floats in your drinks is called "Ice I." It's the least dense form of ice and lighter than water. But at high pressures, like those in crushingly deep oceans like Ganymede's, the ice crystal structures become more compact. "It's like finding a better arrangement of shoes in your luggage -- the ice molecules become packed together more tightly," said Vance. The ice can become so dense that it is heavier than water and falls to the bottom of the sea. The densest and heaviest ice thought to persist in Ganymede is called "Ice VI."

By modeling these processes using computers, the team came up with an ocean sandwiched between up to three ice layers, in addition to the rocky seafloor. The lightest ice is on top, and the saltiest liquid is heavy enough to sink to the bottom. What's more, the results demonstrate a possible bizarre phenomenon that causes the oceans to "snow upwards." As the oceans churn and cold plumes snake around, ice in the uppermost ocean layer, called "Ice III," could form in the seawater. When ice forms, salts precipitate out. The heavier salts would thus fall downward, and the lighter ice, or "snow," would float upward. This "snow" melts again before reaching the top of the ocean, possibly leaving slush in the middle of the moon sandwich.

"We don't know how long the Dagwood-sandwich structure would exist," said Christophe Sotin of JPL. "This structure represents a stable state, but various factors could mean the moon doesn't reach this stable state.

NASA's Galileo spacecraft. Image credit: NASA/JPL-Caltech

Sotin and Vance are both members of the Icy Worlds team at JPL, part of the multi-institutional NASA Astrobiology Institute based at the Ames Research Center in Moffett Field, Calif.

The results can be applied to exoplanets too, planets that circle stars beyond our sun. Some super-Earths, rocky planets more massive than Earth, have been proposed as "water worlds" covered in oceans. Could they have life? Vance and his team think laboratory experiments and more detailed modeling of exotic oceans might help find answers.

Ganymede is one of five moons in our solar system thought to support vast oceans beneath icy crusts. The other moons are Jupiter's Europa and Callisto and Saturn's Titan and Enceladus. The European Space Agency is developing a space mission, called JUpiter ICy moons Explorer or JUICE, to visit Europa, Callisto and Ganymede in the 2030s. NASA and JPL are contributing to three instruments on the mission, which is scheduled to launch in 2022 (see

Other authors of the study are Mathieu Bouffard of Ecole Normale Supérieure de Lyon, France, and Mathieu Choukroun, also of JPL and the Icy World team of the NASA Astrobiology Institute. JPL is managed by the California Institute of Technology in Pasadena for NASA.

For more information about Galileo Mission, visit:

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


Hubble astronomers check the prescription of a cosmic lens

ESA - Hubble Space Telescope logo.

1 May 2014

First ever gravitationally lensed Type Ia supernovae discovered

Cosmic lens MACS J1720+35 helps Hubble to find a distant supernova

Two teams of astronomers using the NASA/ESA Hubble Space Telescope have discovered three distant exploding stars that have been magnified by the immense gravity of foreground galaxy clusters, which act like "cosmic lenses". These supernovae are the first of their type ever to be observed magnified in this way and they offer astronomers a powerful tool to check the prescription of these massive lenses.

Massive clusters of galaxies act as “gravitational lenses” because their powerful gravity bends light passing through them [1]. This lensing phenomenon makes faraway objects behind the clusters appear bigger and brighter — objects that might otherwise be too faint to see, even with the largest telescopes.

The new findings are the first steps towards the most precise prescription — or map — ever made for such a lens. How much a gravitationally lensed object is magnified depends on the amount of matter in a cluster — including dark matter, which we cannot see directly [2]. Astronomers develop maps that estimate the location and amount of dark matter lurking in a cluster. These maps are the lens prescriptions of a galaxy cluster and predict how distant objects behind a cluster will be magnified when their light passes through it. But how do astronomers know this prescription is accurate?

Now, two independent teams of astronomers from the Supernova Cosmology Project and the Cluster Lensing And Supernova survey with Hubble (CLASH) have found a new method to check the prescription of a gravitational lens. They analysed three supernovae — nicknamed Tiberius, Didius and Caracalla — which were each lensed by a different massive galaxy cluster — Abell 383, RXJ1532.9+3021 and MACS J1720.2+3536, respectively. Luckily, two and possibly all three of these supernovae appeared to be a special type of exploding star that can be used as a standard candle [3].

Cosmic lens MACS J1720+35 helps Hubble to find a distant supernova (annotated)

“Here, for the first time, we have found Type Ia supernovae that can be used like an eye chart for each lensing cluster,” explained Saurabh Jha of Rutgers University, USA, a member of the CLASH team. “Because we can estimate the intrinsic brightness of the Type Ia supernovae, we can independently measure the magnification of the lens, which is not possible with other background sources."

The teams measured the brightnesses of the lensed supernovae and compared them to the explosion's intrinsic brightness to calculate how much brighter the exploding stars' were made due to gravitational lensing. One supernova in particular stood out, appearing to be about twice as bright as would have been expected if not for the cluster's magnification power.

The three supernovae were discovered in the CLASH survey, which used Hubble to probe the distribution of dark matter in 25 galaxy clusters. Two of the supernovae were found in 2012; the other in 2010 to 2011.

To perform their analyses, both teams used Hubble observations alongside observations from both space and ground-based telescopes to provide independent estimates of the distances to these exploding stars [4].

In some cases the observations allowed direct confirmation of a Type Ia pedigree. In other cases the supernova spectrum was weak or overwhelmed by the light of its parent galaxy. In those cases the brightening and fading behaviour of the supernovae in different colours was used to help establish the supernova type.

Cosmic lens Abell 383 helps Hubble to find a distant supernova (annotated)

Each team compared its results with independent theoretical models of the clusters' dark matter content. They each came to the same conclusions: that the predictions fit the models.

“It is encouraging that the two independent studies reach quite similar conclusions,” explained Supernova Cosmology Project team member Jakob Nordin of the E.O. Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley. “These pilot studies provide very good guidelines for making future observations of lensed supernovae even more accurate.” Nordin is the lead author on the team's science paper describing the findings.

The Supernova Cosmology Project's galaxy cluster models were created by team members Johan Richard of the University of Lyon in France, and Jean-Paul Kneib of Ecole Polytechnique Federale de Lausanne in Switzerland. “It’s really great to see that these supernovae are behaving in the way we expected,” says Kneib. “The more confirmation we get that our complex cluster models are correct, the more we can rely on them, and use them to probe the early Universe.”

“Building on our understanding of these lensing models also has implications for a wide range of key cosmological studies,” added Supernova Cosmology Project leader Saul Perlmutter of Berkeley Lab and the University of California, Berkeley. “These lens prescriptions yield measurements of the cluster masses, allowing us to probe the cosmic competition between gravity and dark energy as matter in the Universe gets pulled into galaxy clusters.” Dark energy being a mysterious and invisible energy that is accelerating the Universe's expansion.

Cosmic lens RXJ1532.9+3021 helps Hubble to find a distant supernova (annotated)

The astronomers are optimistic that Hubble surveys such as Frontier Fields and future telescopes, including the infrared James Webb Space Telescope, will find more of these unique exploding stars. This is important as if you want to check the prescription of your lens, you really want to check it in more than one place. “Hubble is already hunting for them in the Frontier Fields, a three-year Hubble survey of the distant universe which uses massive galaxy clusters as gravitational lenses, to reveal what lies beyond them” said CLASH team member Brandon Patel of Rutgers University, the lead author on the science paper announcing the CLASH team's results.

The results from the CLASH team will appear in the May 2014 issue of The Astrophysical Journal. The Supernova Cosmology Project's findings will appear in the May 2014 edition of the Monthly Notices of the Royal Astronomical Society.

Hubble orbiting Earth


[1] Albert Einstein predicted this effect in his theory of general relativity.

[2] Dark matter is believed to make up the bulk of the Universe's matter, and is therefore the source of most of a cluster's gravity.

[3] An astronomical "standard candle" is any type of luminous object whose intrinsic power is so accurately determined that it can be used to make distance measurements based on the rate the light dims over astronomical distances.

[4] The astronomers obtained observations in visible light from Hubble's Advanced Camera for Surveys and in infrared light from the Wide Field Camera 3.

More information:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The work is published in two papers, the CLASH team in The Astrophysical Journal and the Supernova Cosmology Project's findings in Monthly Notices of the Royal Astronomical Society.

The CLASH survey is led by Marc Postman of the Space Telescope Science Institute. The CLASH supernova project is co-led by Adam Riess of the Space Telescope Science Institute and Johns Hopkins University and Steven Rodney of Johns Hopkins University. Aiding with the analysis on this Hubble study are Curtis McCully of Rutgers University and Julian Merten and Adi Zitrin of the California Institute of Technology in Pasadena. Lead author of the paper was Brandon Patel.

The Supernova Cosmology Project included Jakob Nordin and Saul Perlmutter and others who worked on the supernovae analysis are David Rubin of Florida State University in Tallahassee and Greg Aldering of Lawrence Berkeley National Lab.


Images of Hubble:

NASA Press Release:

Images, Video, Text, Credits: NASA, ESA, S. Perlmutter (UC Berkeley, LBNL), A. Koekemoer (STScI), M. Postman (STScI), A. Riess (STScI/JHU), J. Nordin (LBNL, UC Berkeley), D. Rubin (Florida State), and C. McCully (Rutgers University).

Best regards,

Length of Exoplanet Day Measured for First Time

ESO - European Southern Observatory logo.

May 1, 2014

VLT measures the spin of Beta Pictoris b

Artist’s impression of the planet Beta Pictoris b

Observations from ESO’s Very Large Telescope (VLT) have, for the first time, determined the rotation rate of an exoplanet. Beta Pictoris b has been found to have a day that lasts only eight hours. This is much quicker than any planet in the Solar System — its equator is moving at almost 100 000 kilometres per hour. This new result extends the relation between mass and rotation seen in the Solar System to exoplanets. Similar techniques will allow astronomers to map exoplanets in detail in the future with the European Extremely Large Telescope (E-ELT).

The universal relation between mass and rotation speed of planets

Exoplanet Beta Pictoris b orbits the naked-eye star Beta Pictoris [1], [2], which lies about 63 light-years from Earth in the southern constellation of Pictor (The Painter’s Easel). This planet was discovered nearly six years ago and was one of the first exoplanets to be directly imaged. It orbits its host star at a distance of only eight times the Earth-Sun distance (eso1024) — making it the closest exoplanet to its star ever to be directly imaged [3].

Using the CRIRES instrument on the VLT, a team of Dutch astronomers from Leiden University and the Netherlands Institute for Space Research (SRON) have now found that the equatorial rotation velocity of exoplanet Beta Pictoris b is almost 100 000 kilometres per hour. By comparison, Jupiter’s equator has a velocity of about 47 000 km per hour [4], while the Earth’s travels at only 1700 km per hour [5]. Beta Pictoris b is more than 16 times larger and 3000 times more massive than the Earth, yet a day on the planet only lasts 8 hours.

Map of the sky around Beta Pictoris

“It is not known why some planets spin fast and others more slowly,” says co-author Remco de Kok, “but this first measurement of an exoplanet’s rotation shows that the trend seen in the Solar System, where the more massive planets spin faster, also holds true for exoplanets. This must be some universal consequence of the way planets form.”

Beta Pictoris b is a very young planet, only about 20 million years old (compared to 4.5 billion years for the Earth) [6]. Over time, the exoplanet is expected to cool and shrink, which will make it spin even faster [7]. On the other hand, other processes might be at play that change the spin of the planet. For instance, the spin of the Earth is slowing down over time due to the tidal interactions with our Moon.

Around Beta Pictoris

The astronomers made use of a precise technique called high-dispersion spectroscopy to split light into its constituent colours — different wavelengths in the spectrum. The principle of the Doppler effect (or Doppler shift) allowed them to use the change in wavelength to detect that different parts of the planet were moving at different speeds and in opposite directions relative to the observer. By very carefully removing the effects of the much brighter parent star they were able to extract the rotation signal from the planet.

“We have measured the wavelengths of radiation emitted by the planet to a precision of one part in a hundred thousand, which makes the measurements sensitive to the Doppler effects that can reveal the velocity of emitting objects,” says lead author Ignas Snellen. “Using this technique we find that different parts of the planet’s surface are moving towards or away from us at different speeds, which can only mean that the planet is rotating around its axis“.

Zooming in on Beta Pictoris

This technique is closely related to Doppler imaging, which has been used for several decades to map the surfaces of stars, and recently that of a brown dwarf [8] — Luhman 16B (eso1404). The fast spin of Beta Pictoris b means that in the future it will be possible to make a global map of the planet, showing possible cloud patterns and large storms.

“This technique can be used on a much larger sample of exoplanets with the superb resolution and sensitivity of the E-ELT and an imaging high-dispersion spectrograph. With the planned  Mid-infrared E-ELT Imager and Spectrograph (METIS) we will be able to make global maps of exoplanets and characterise much smaller planets than Beta Pictoris b with this technique”, says METIS principal investigator and co-author of the new paper, Bernhard Brandl.


[1] Beta Pictoris has many other names, e.g. HD 39060, SAO 234134 and HIP 27321.

[2] Beta Pictoris is one of the best-known examples of a star surrounded by a dusty debris disc. This disc is now known to extend out to about 1000 times the distance between the Earth and the Sun. Earlier observations of Beta Pictoris’s planet were reported in eso0842, eso1024 and eso1408.

[3] The observations made use of the adaptive optics technique compensating for the Earth’s atmospheric turbulence which can distort images obtained at even the best sites in the world for astronomy. It allows astronomers to create super-sharp images, almost as good as those that could be seen from space.

[4] Since Jupiter has no solid surface from which to determine the planet’s rotation rate, we take the rotation speed of its equatorial atmosphere, which is 47 000 km per hour.

[5] The Earth’s rotation speed at the equator is 1674.4 km per hour.

[6] Earlier measurements suggested that the system was younger.

[7] This is a consequence of the conservation of angular momentum and is the same effect that makes a spinning ice skater turn more rapidly when they bring their arms closer to their body.

[8] Brown dwarfs are often dubbed “failed stars” as, unlike stars such as the Sun, they are not massive enough to sustain nuclear fusion reactions.

More information:

This research was presented in a paper “Fast spin of a young extrasolar planet”, by I. Snellen et al., to appear in the to appear in the journal Nature on 1 May 2014.

The team is composed of Ignas A. G. Snellen (Leiden Observatory, Leiden University, Leiden, the Netherlands), Bernhard Brandl (Leiden Observatory), Remco J. de Kok (Leiden Observatory, SRON Netherlands Institute for Space Research, Utrecht, the Netherlands), Matteo Brogi (Leiden Observatory), Jayne Birkby (Leiden Observatory) and Henriette Schwarz (Leiden Observatory).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.


Research paper:

Photos of the VLT:

Photos of CRIRES:

The CRIRES instrument on the VLT:

More about METIS: A Mid-Infrared E-ELT Imager and Spectrograph:

Video describing the Beta Pictoris b result (from Leiden University/NOVA, the Netherlands):

Images, Text, Credits: ESO L. Calçada/N. Risinger ( Snellen (Leiden University)/IAU and Sky & Telescope/Digitized Sky Survey 2/Video: ESO/Digitized Sky Survey 2/Nick Risinger ( Calçada. Music: movetwo.


mardi 29 avril 2014

Vega another light-lift success!

ESA / ARIANESPACE - Flight VV03 poster.

April 29, 2014

Vega Flight VV03

The latest Vega launch delivers Kazakhstan’s first Earth observation satellite to orbit

Vega flight VV03 liftoff! (Screenshot by Juli Fowler)

Arianespace is on track for a record launch performance in 2014 following tonight’s Vega mission from the Spaceport in French Guiana, which successfully orbited a pioneering Earth observation satellite for the Republic of Kazakhstan.

Lifting off from the SLV launch site at 10:35:15 p.m. local time – which was the planned precise moment of launch – Vega was put through its paces to loft DZZ-HR, renamed “KasEOSat-1” after reaching Sun-synchronous orbit, during a flight lasting 55 minutes.

Arianespace Flight VV03 - KasEOSat-1

As a 900-kg.-class Earth observation spacecraft, KasEOSat-1 is to provide the Republic of Kazakhstan with a complete range of civil applications – including monitoring of natural and agricultural resources, provision of mapping data, and support for rescue operations in the event of a natural disaster.

Tonight’s mission – designated Flight VV03 – marked the third launch of a Vega, which joins Arianespace’s medium-lift Soyuz and heavyweight Ariane 5 to form the world’s most capable family of launchers, operating side-by-side at the Spaceport.

Conceived for the orbiting of small- to medium-sized satellites, including institutional and scientific spacecraft, Vega was developed in the framework of a European Space Agency (ESA) program financed by Italy, France, Germany, Spain, Belgium, the Netherlands, Switzerland and Sweden.  The launcher design authority and prime contractor is Italy’s ELV – a joint venture company of Avio and the Italian ASI space agency – while Arianespace is responsible for handling the launch operations.

KasEOSat-1 satellite (Credit: Günter Space Page)

The first Vega launch (designated Flight VV01 in Arianespace’s numbering system) was a qualification mission performed in February 2012, carrying the LARES laser relativity satellite, a small ALMASat-1 technology microsatellite demonstrator, and seven CubeSats.   It was followed by Flight VV02 in May 2013, which orbited the Proba-V, VNREDSat-1 and ESTCube-1 satellites.

Tonight’s Vega success was Arianespace’s fourth mission so far in 2014, putting the company on track to perform a total of 12 launches from Europe’s Spaceport during the year – which would mark a new record, surpassing the 10-launch mark set in 2012. It follows the Ariane 5 flight that orbited ABS-2 and Athena-Fidus in February; Ariane 5’s March success with ASTRA 5B and Amazonas 4A; and the Soyuz mission to loft Sentinel-1A earlier this month.

Related links:

Arianespace website:

Airbus Defence and Space website:

European Space Agency website:

Italian Space Agency:

ELV, SpA website:

Images (mentioned), Video, Text, Credits: Arianespace / Arianespace TV / Launch screen capture by Juli Fowler.

Best regards,

NASA Satellite Sees Colder Temperatures in Severe Weather Thunderstorms

NASA - Aqua Mission logo.

April 29, 2014

The weather system that dropped tornadoes in seven central and southern U.S. states on April 27-28, moved east and generated more tornadoes on April 29. NASA's Aqua satellite gathered temperature data on the thunderstorm cloud tops in the system and found them to be higher in the atmosphere and colder. The tornado outbreak over the evening and overnight hours of April 28-29 is thought to have generated more tornadoes in northern Mississippi and Alabama.

NASA's Aqua satellite passed over the eastern U.S. early in the morning on April 29 at 07:41 UTC/3:41 a.m. EDT and gathered infrared data associated with the storms associated with the frontal system that generated tornadoes on April 28 and early this morning, April 29. The Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite provided that infrared data. A false-colored image of the storm system using the infrared data was created by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

Image above: On April 29 at 3:41 a.m. EDT, NASA's Aqua satellite's infrared data showed very high, powerful thunderstorms (purple) in the frontal system that generated more tornadoes. Image Credit: NASA/JPL, Ed Olsen.

The AIRS image showed very cold cloud top temperatures indicating that the thunderstorms had strong uplift that pushed cloud tops near the top of the troposphere. Temperatures drop to just under 220 degrees kelvin at the top of the troposphere (and where the tropopause begins).

In the early morning imagery from today (April 29) AIRS data showed minimum temperature to be near 190 kelvin (-117.7 F/-83.1 C), which is even colder than yesterday. That means the storms early this morning were higher in the atmosphere and had the potential to be stronger than those on April 28. On April 28, AIRS data showed some thunderstorms with cloud tops as cold as 200 kelvin (-99.6 F/-73.1C).

Image above: NOAA's National Forecast chart for April 29, 2014 showed a large area in the Eastern U.S. that has the potential for severe weather (yellow).
Image Credit: NOAA.

A low pressure center associated with the fronts is located over Iowa. A warm front extends east of the low bringing warm, moist air into the southeastern U.S. A stationary front stretches south from that low pressure area to another low.

pressure area over eastern Texas. NOAA's National Weather Service Storm Prediction Center is forecasting "Severe thunderstorms expected over parts of the Gulf Coast States this afternoon and tonight."

For updated information about the storm system, visit NOAA's NWS website:

For more information about GOES satellites, visit: or

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


Me and My Shadow

NASA / ESA - Cassini Mission to Saturn patch.

April 29, 2014

Saturn's rings cast shadows on the planet, but the shadows appear to be inside out! The edge of Saturn's outermost A ring can be seen at the top left corner of the image.  Moving towards the bottom of the page, one can see the faint Cassini Division, the opaque B ring and the innermost C ring, which contains several ringlets that appear dark against Saturn in this geometry.  The bottom half of the image features the shadows of these rings in reverse order superposed against the disk of the planet: the C ring, the B ring, the Cassini Division and the inner half of the A ring.

This view looks toward the unilluminated side of the rings from about 28 degrees below the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Dec. 2, 2013, using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 752 nanometers.

The view was acquired at a distance of approximately 750,000 miles (1.2 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 57 degrees. Image scale is 45 miles (72 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 and The Cassini imaging team homepage is at

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


Herschel discovers mature galaxies in the young Universe

ESA - Herschel Mission patch.

29 April 2014

New Herschel results have given us a remarkable insight into the internal dynamics of two young galaxies. Surprisingly, they have shown that just a few billion years after the Big Bang, some galaxies were rotating in a mature way, seemingly having completed the accumulation of their gas reservoirs.

When galaxies form, they accumulate mass by gravitationally attracting vast, external gas clouds. As the gas clouds enter the galaxy, they fall into haphazard orbits. These disordered paths cause turbulence in the host galaxies, which can drive star formation.

To investigate the internal conditions of forming galaxies James Rhoads and Sangeeta Malhotra, both from Arizona State University, and colleagues targeted two young galaxies, known as S0901 and the Clone. The light from both galaxies has taken 10 billion years to reach us across space. Thus, we are seeing them when they were comparatively young.

Image above: Lensed image of galaxy S0901. Credit: NASA/STScI; S. Allam and team; and the Master Lens Database (, L. A. Moustakas, K. Stewart, et al. (2014).

"The purpose of this project is to study the physical conditions of gas in those galaxies. We wanted to know: are they similar to the galaxies around us or is there some difference in their physical conditions," says Rhoads.

The two galaxies they choose to study are average galaxies for that time in cosmic history. This means that they are about 10-20 per cent the size of our Milky Way, which is considered an average galaxy in the present-day Universe.

Studying galaxies so far away is usually hampered because they appear too dim to study effectively but in this case, the researchers were helped by a cosmic magnifier known as a gravitational lens. The two galaxies both sit behind intervening groups of galaxies, whose gravity warps space. As described by Albert Einstein's General Theory of Relativity, this warping acts like a lens. Although it distorts the images of the young galaxies, it helps by magnifying their light, thus bringing them within reach of Herschel's HIFI instrument.

The researchers used HIFI to investigate the infrared light of ionized carbon, which is emitted at a wavelength of 158 micrometres (a frequency of 1900 GHz). This spectral line is produced in the clouds that surround star-forming regions. HIFI showed the line was broadened into a double peak, and this allowed the motion of the gas to be fitted with a model.

Graphic above: Herschel spectrum of the galaxy S0901. Credit: ESA/Herschel/HIFI. Acknowledgments: James Rhoads and Sangeeta Malhotra, Arizona State University, USA.

Firstly, the team fitted the overall rotation of the galaxy, and then the turbulence in the gas clouds. To their surprise they found that galaxy S0901 was extremely well behaved. Instead of turbulence, it was found to be in orderly rotation, much more akin to the majestic galaxies of today.

"Usually, when astronomers examine galaxies at this early era, they find that turbulence plays a much greater role than it does in modern galaxies. But S0901 is a clear exception to that pattern, and the Clone could be another," says Rhoads.

The Clone, the second galaxy in their study, could also be fitted by an orderly rotation. However, because it was somewhat dimmer, the quality of the data was not so good. This meant that the data could also be fitted with a highly turbulent model, as conventional wisdom would expect.

"Galaxies 10 billion years ago were making stars more actively than they do now," says Malhotra, "They usually also show more turbulence, likely because they are accumulating gas faster than a modern galaxy does. But here we have cases of early galaxies that combine the 'calm' rotation of a modern one with the active star formation of their early peers. This suggests first that these galaxies have finished accumulating their gas, at least for now. But it also seems that turbulence is not actually required to trigger that early, active star formation."

Image above: Herschel spectrum of the Clone. Credit: ESA/Herschel/HIFI. Acknowledgments: James Rhoads and Sangeeta Malhotra, Arizona State University, USA.

Malhotra acknowledges the preliminary nature of their study. "This is not the last word on this. We need a bigger sample to be sure of our conclusions," she says.

But that bigger sample will not be investigated by Herschel. As predicted, the liquid helium coolant needed to keep HIFI and Herschel's other instruments working ran out in April 2013. Instead the researchers hope to continue the work pioneered by Herschel using the Atacama Large Millimeter/submillimeter Array (ALMA), a ground-based array of 66 radio dishes in Chile.

"It is mind-boggling that with Herschel/HIFI – admittedly with the help of gravitational lensing – it has been possible to study the internal gas kinematics in galaxies when the Universe was only a few billion years old, and what we can learn about them this way. This pioneering work by Herschel is bound to be continued," says Göran Pilbratt, Herschel Project Scientist at ESA.

Background Information

The study reported here is based on observations performed with the Heterodyne Instrument for the Far-Infrared (HIFI) on board ESA's Herschel Space Observatory of SDSS090122.37+181432.3, referred to as S0901, and SDSS J120602.09+514229.5, known as the Clone. The results are published in "Herschel Extreme Lensing Line Observations: Dynamics of two strongly lensed star forming galaxies near redshift z = 2", by J. Rhoads et al., to appear in the 2014 May 20 issue of The Astrophysical Journal, volume 787, issue 1.

Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

The HIFI instrument is a very high-resolution heterodyne spectrometer and operates in seven bands covering the wavelength range between 157 and 625 µm. HIFI has been designed and built by a consortium of institutes and university departments across Europe, Canada, and the United States under the leadership of SRON Netherlands Institute for Space Research, the Netherlands, with major contributions from Germany, France, and the USA. HIFI Consortium members are: CSA, U. Waterloo (Canada); CESR, LAB, LERMA, IRAM (France); KOSMA, MPIfR, MPS (Germany); NUI Maynooth (Ireland); ASI, IFSI-INAF, Osservatorio Astrofisico di Arcetri-INAF (Italy); SRON, TUD (Netherlands); CAMK, CBK (Poland); Observatorio Astronómico Nacional (IGN), Centro de Astrobiología (CSIC-INTA) (Spain); Chalmers University of Technology - MC2, RSS & GARD, Onsala Space Observatory, Swedish National Space Board, Stockholm University - Stockholm Observatory (Sweden); ETH Zurich, FHNW (Switzerland); Caltech, JPL, NHSC (USA).

Herschel was launched on 14 May 2009 and completed science observations on 29 April 2013.

For more information about Herschel Mission, visit:

Images (mentioned), Text, Credit: ESA.


Orbit Height of the International Space Station increased of 2.15 km

ROSCOSMOS - Russian Vehicles patch.


April 29, 2014 underwent elective correction orbit of the International Space Station.

According to calculations by the ballistic and navigation support Mission Control Center FSUE TsNIIMash today in 11 hours and 45 minutes Moscow time included engines cargo spacecraft Progress M-21M. Ship's engines worked 566.8 seconds. As a result, ISS received a velocity increment of 1.23 m/s. The average height of the station's orbit has increased by 2.15 km (1mi 974.03yd) and reached 417.2 km (259mi 415.47yd).

ISS reboost by Progress-M

Orbit correction station flight was performed in order to create optimal conditions for docking with the ISS manned spacecraft Soyuz TMA-13M with a new crew, the launch of which is scheduled for May 28 from the Baikonur Cosmodrome.

ROSCOSMOS Press Release:

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


lundi 28 avril 2014

Satellite Movie Shows U.S. Tornado Outbreak from Space

NOAA logo.

April 28, 2014

GOES Animation of the Tornadoes from Apr. 27-28, 2014

Video above: This animation of NOAA's GOES-East satellite data shows the development and movement of the weather system that spawned tornadoes affecting seven central and southern U.S. states on April 27-28, 2014. Image Credit: NASA/NOAA GOES Project.

NASA has just released an animation of visible and infrared satellite data from NOAA's GOES-East satellite that shows the development and movement of the weather system that spawned tornadoes affecting seven central and southern U.S. states on April 27-28, 2014. NASA's Aqua satellite captured infrared data on the system that revealed powerful storms, high into the troposphere.

This storm system generated reports of tornadoes from Nebraska, Kansas, Iowa, Oklahoma, Arkansas, Louisiana, and Mississippi.

NOAA's GOES-East satellite. Image Credit: NOAA

Coupled with local weather observations, soundings, and computer models, data from satellites like NOAA's Geostationary Operational Environmental Satellite or GOES-East (also known as GOES-13) gives forecasters information about developing weather situations. In real-time, the NOAA's GOES-East satellite data in animated form showed forecasters how the area of severe weather was developing and moving.

Image above: This NOAA GOES-East satellite image from Monday, April 28, 2014 at 13:01 UTC/9:01 a.m. EDT shows the same storm system that generated the severe weather outbreak yesterday, has moved to the east. Image Credit: NASA/NOAA GOES Project.

NOAA's GOES-East satellite sits in a fixed orbit in space capturing visible and infrared imagery of weather over the eastern U.S. and Atlantic Ocean. The GOES-East satellite is operated by the National Oceanic and Atmospheric Administration. NASA/NOAA's GOES Project at the NASA Goddard Space Flight Center in Greenbelt, Md. created the animation of GOES-East satellite data that covered the period during the tornado outbreak.

The GOES-East animation of visible and infrared imagery runs 31 seconds. The animation begins on April 27 at 00:15 UTC (April 26 at 8:15 p.m. EDT) and runs through April 28 at 14:15 UTC/10:15 a.m. EDT. By 14:45 UTC/10:45 a.m. EDT on April 27 the animation shows the squall line of thunderstorms developing.

To create the video and imagery, NASA/NOAA's GOES Project takes the cloud data from NOAA's GOES-East satellite and overlays it on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument that flies aboard NASA's Aqua and Terra satellites. Together, those data created the entire picture of the storm system and show its movement.

Image above: This false-colored infrared image from the AIRS instrument aboard NASA's Aqua satellite shows the cold cloud top temperatures associated with the severe thunderstorms that brought severe weather to seven states on April 27. Image Credit: NASA/JPL, Ed Olsen.

A NASA satellite also captured an image of the storm, collecting infrared data on it as it passed overhead on April 27. At NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. a false-colored image was created of the storm system using data gathered by the Atmospheric Infrared Sounder (AIRS) instrument that flies aboard NASA's Aqua satellite on April 27 at 18:59 UTC (1:59 p.m. CDT). The AIRS image showed very cold cloud top temperatures indicating that the thunderstorms had strong uplift that pushed cloud tops to the top of the troposphere. Some of those thunderstorms had cloud tops as cold as 200 kelvin (-99.6 F/-73.1C). Temperatures drop to just under 220 degrees kelvin at the top of the troposphere (and where the tropopause begins).

"AIRS data shows spatial extent of strong convection [rapidly rising air that condenses and forms clouds] in the slow-moving severe storm system that spawned tornadoes in Arkansas, Oklahoma and Iowa," said Ed Olsen, creator of the AIRS image at NASA JPL. The AIRS image showed the thunderstorms with coldest cloud top temperatures stretched from eastern Nebraska, through western Iowa, western Missouri, northern Arkansas and southeast into northern Mississippi and Alabama.

According to the, the National Weather Service’s Storm Prediction Center counted 31 tornadoes on Sunday, April 27, however, that number is being refined as reports are analyzed.

Image above: This image from NOAA's Storm Prediction Center shows preliminary reports of the severe weather outbreak from April 27, 2014. Image Credit: NOAA/SPC.  

CBS News reported that one tornado touched down 10 miles west of Little Rock, Arkansas around 7 p.m. CDT (at around 22:02 UTC in the GOES animation) and stayed on the ground for about 80 miles passing near several suburbs north of the city. That tornado was reported to be one-half mile wide.

The same system that spawned these tornadoes is expected to bring the possibility for severe weather further east on April 28 from Cincinnati, Ohio to New Orleans, La. For more information about current risks for severe weather, visit NOAA's Storm Prediction Center at:

GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. Geostationary describes an orbit in which a satellite is always in the same position with respect to the rotating Earth. This allows GOES to hover continuously over one position on Earth's surface, appearing stationary. As a result, GOES provide a constant vigil for the atmospheric "triggers" for severe weather conditions such as tornadoes, flash floods, hail storms and hurricanes.

To download the GOES animation:

For updated information about the storm system, visit NOAA's NWS website:

For more information about GOES satellites, visit: or

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


Drill Here? NASA's Curiosity Mars Rover Inspects Site

NASA - Mars Science Laboratory (MSL) patch.

April 28, 2014

Sandstone Target 'Windjana' May Be Next Martian Drilling Site

Image above: NASA's Curiosity Mars rover has driven within robotic-arm's reach of the sandstone slab at the center of this April 23 view from the rover's Mast Camera. The rover team plans to have Curiosity examine a target patch on the rock, called "Windjana," to aid a decision about whether to drill there. Image Credit: NASA/JPL-Caltech/MSSS.

The team operating NASA's Curiosity Mars rover is telling the rover to use several tools this weekend to inspect a sandstone slab being evaluated as a possible drilling target.

If this target meets criteria set by engineers and scientists, it could become the mission's third drilled rock, and the first that is not mudstone. The team calls it "Windjana," after a gorge in Western Australia.

The planned inspection, designed to aid a decision on whether to drill at Windjana, includes observations with the camera and X-ray spectrometer at the end of the rover's arm, use of a brush to remove dust from a patch on the rock, and readings of composition at various points on the rock with an instrument that fires laser shots from the rover's mast.

Curiosity Mars Rover Beside Sandstone Target 'Windjana'

Image above: This image from the Navigation Camera on NASA's Curiosity Mars rover shows a sandstone slab on which the rover team has selected a target, "Windjana," for close-up examination. The target is on the approximately 2-foot-wide rock seen in the right half of this April 23, 2014, view. Image Credit: NASA/JPL-Caltech.

Curiosity's hammering drill collects powdered sample material from the interior of a rock, and then the rover prepares and delivers portions of the sample to onboard laboratory instruments. The first two Martian rocks drilled and analyzed this way were mudstone slabs neighboring each other in Yellowknife Bay, about 2.5 miles (4 kilometers) northeast of the rover's current location at a waypoint called "the Kimberley." Those two rocks yielded evidence of an ancient lakebed environment with key chemical elements and a chemical energy source that provided conditions billions of years ago favorable for microbial life.

From planned drilling at Windjana or some nearby location on sandstone at the Kimberley, Curiosity's science team hopes to analyze the cement that holds together the sand-size grains in the rock.

"We want to learn more about the wet process that turned sand deposits into sandstone here," said Curiosity Project Scientist John Grotzinger, of the California Institute of Technology in Pasadena. "What was the composition of the fluids that bound the grains together? That aqueous chemistry is part of the habitability story we're investigating."

Location of Mars Sandstone Target 'Windjana'

Image above: In this Mars Reconnaissance Orbiter view of the Curiosity rover mission's waypoint called "the Kimberley," the red dot indicates the location of a sandstone target, "Windjana," selected for close-up inspection. The image was taken April 11, 2014, before the rover arrived at Windjana. Image Credit: NASA/JPL-Caltech/Univ. of Arizona.

Understanding why some sandstones in the area are harder than others also could help explain major shapes of the landscape where Curiosity is working inside Gale Crater. Erosion-resistant sandstone forms a capping layer of mesas and buttes. It could even hold hints about why Gale Crater has a large layered mountain, Mount Sharp, at its center.

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

The spectrometer on the rover's robotic arm is the Alpha Particle X-Ray Spectrometer (APXS), which was provided by the Canadian Space Agency. The camera on the arm is the Mars Hand Lens Imager (MAHLI), built and operated by Malin Space Science Systems, San Diego. The laser on the mast is part of the Chemistry and Camera instrument (ChemCam), from the U.S. Department of Energy's Los Alamos National Laboratory in New Mexico and the French national space agency, CNES. The rover's wire-bristle brush, the Dust Removal Tool, was built by Honeybee Robotics, New York.  

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

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