Creating a 'Perpetual Eclipse' in Space

StarTiger-2 external coronagraph demonstrator during testing

In September 2009, a group of prominent scientists was convened by the European Space Agency (ESA) at one of its research facilities with a single objective – produce a space-based setup that would allow for the continuous analysis of a portion of the Sun hiding in plain sight. The results of the investigation were announced yesterday, April 27, as the six-month-long research project was officially closed down on time, at the agency's European Space Research and Technology Center (ESTEC), in the Netherlands.

The StarTiger project is one of ESA's latest endeavors, and it was developed at the Laboratoire Astrophysique d’Marseille (LAM), where the science team was convened. Inside a clean room at the facility, the researchers constructed a scale-model prototype of the new mission, whose main goal is to create a perpetual eclipse in space. Usually, the edges of the Sun are only visible from Earth during a full eclipse by the Moon, but the astronomical event happens rather rare. What ESA wanted to achieve is the capability to conduct eclipse study around the clock.

The solution its research team proposed was constructing a double-satellite system. The instruments would fly in a close, tight formation, where the one in front would cast a perennial shadow on the one in the back. This approach raises monumental engineering problems, given that both spacecraft would be flying at high speeds through space. The navigation and control systems are the most difficult aspects to set up, but the endeavor is not impossible, scientists say.

“ESA’s StarTiger is a new R&D approach, one that has paid off handsomely here. This integrated ‘breadboard’ demonstrator has been completed in just six months, including all necessary subsystems, mathematical models and software, to not only validate the external coronagraph concept but assess its performance in practical terms,” explained at yesterday's ceremony the supervisor of the initiative, expert Peter de Maagt.

“The main objective was achieved together with several secondary objectives. The idea was to perform relative positioning between the two satellites and absolute positioning with respect to the Sun. Working face-to-face in the same room was our key to success, considering the schedule we faced. We combined our various competences to solve the many problems that arose along the way,” added LAM team leader Sebastien Vives. He managed the main research group of seven experts, who were supported by 20 other investigators.

Planck Casts New Light on Stellar Formation

A series of recent experiments has revealed that, more often than not, the halos of dark matter surrounding massive galaxy clusters are flattened and shaped like a cigar. Until now, astrophysicists believed that the mysterious stuff, which is believed to be five times more abundant than regular matter around the Universe, would clump up in rounded spheres. However, observations appear to paint a different picture, and experts are currently working on models that would help explain that.

The discovery could finally lead to studies that would result in the direct detection of the peculiar type of matter, whose existence can only be inferred from the gravitational pull it exerts on normal matter around it. “There are clear theoretical predictions that we expect dark mater halos to be flattened like this. It's a very beautiful, very clean and direct measurement of that,” explains expert Graham P. Smith, who is based at the University of Birmingham, in the United Kingdom. He is also a coauthor of the new study, which will appear in an upcoming issue of the esteemed scientific publication Monthly Notices of the Royal Astronomical Society.

In the new studies, the investigators looked at about 20 galaxy clusters, which are massive collections of galaxies, held together by strong gravitational interactions. In order to see the effect dark matter has on the largest organized structures in the Universe, the researchers used gravitational lensing. This observations technique analyzes how much light is bent when mass wraps time-space in order to determine the mass of celestial objects beyond. The Mauna Kea, Hawaii-based Subaru Telescope was used for the study, and the team took advantage of the Prime Focus Camera above all other instruments.

“What we're probing with these gravitational lensing observations is the dark matter distribution, because the dark matter dominates the mass on these large scales,” Smith says. The research team in charge of the study was led by National Astronomical Observatory of Japan expert Masamune Oguri and University of Tokyo scientist Masahiro Takada. The cigar-like shapes of these dark matter halos have been predicted in computer models of the cold dark matter theory, but thus far they have not been evidenced in practice in such a large number of galaxy clusters, Space reports.

“Precise measurements of the Cosmic Microwave Background are crucial to cosmology, and to understanding how our Universe formed and evolved. Attaining the highest-sensitivity (a few parts per million), highest-angular resolution (5 arcminutes) maps of the CMB – the goal of the Planck mission – requires the removal of the 'foreground' emission arising from the Milky Way. The information gleaned during this process is providing, as a by-product, a unique view of the processes that led to the formation of the stars in the galaxies that populate our Universe,” ESA officials write in a press release.

Planck maps the sky in nine frequencies using two state-of-the-art instruments, designed to produce high-sensitivity, multi-frequency measurements of the diffuse sky radiation: the High Frequency Instrument (HFI) includes the frequency bands 100 – 857 GHz, and the Low Frequency Instrument (LFI) includes the frequency bands 30-70 GHz. The first Planck all-sky survey began in August 2009 and is 98% complete (as of mid-March 2010).

Venus Express Does Aerobreaking Maneuvers

The European Space Agency (ESA) has been operating the Venus Express spacecraft around the second planet from the Sun since April 2006. The instruments aboard the probe managed to collect a wealth of data about the surface and atmosphere of the space rock, and contributed considerably to our understanding of its structure. In order to boost the amount of data we have on Venus, experts at ESA conducted a series of 5 aerobreaking maneuvers in its sweltering atmosphere last week, during which the solar panels on the spacecraft were used as sails to propel it through the chemical mix.

This meant that the entire probe was basically transformed into a highly-sensitive sensor, which proved to be very suitable for assessing the density of the atmosphere above Venus, just 111 miles, or 180 kilometers, over the cloud cover that conceals its surface. “The aerodrag campaign went without problem, and conclusively demonstrated that Venus Express can be securely and accurately used to sense the density of the planet's atmosphere. Venus Express has shown once again that it is a very capable satellite,” explained the Venus Express spacecraft operations manager, Octavio Camino.

Measuring atmospheric density with a probe such as this one is fairly easy. All engineers had to do is orient its solar panels in a manner that saw a small amount of torque force being generated in the body of the spacecraft. This happened because the instrument was passing through the faintest traces of the Venusian atmosphere, which created drag. The density could then be inferred from the amount of correction that reaction wheels needed to apply in order to keep the craft in its planned trajectory in space. These wheels counter-rotate within Venus Express itself, and are considered to play a fundamental role in ensuring the success of small correction maneuvers.

According to ESA mission managers, the spacecraft is expected to continue performing such aerobreaking maneuvers well into 2011 and 2012, even though the mission was originally scheduled to end back in May 2009. Due to the amazing performances of the probe, the mission was first extended for 4 months, and then, in September 2009, it was extended to 2010. However, engineers in charge of the machine are convinced that there's still life in it, and that the mission will receive additional funding, Space reports.

Surfing an alien atmosphere

Venus Express has completed an 'aerodrag' campaign that used its solar wings as sails to catch faint wisps of the planet’s atmosphere. The test used the orbiter as an exquisitely accurate sensor to measure atmospheric density barely 180 km above the hot planet.

During five aerodrag measurements last week, Venus Express' solar arrays and control systems were operated as one big flying sensor, with the solar arrays rotated at various angles to the direction of flight.

The special configuration exposed the wings to the vanishingly faint wisps of atmosphere that reach to the boundary of space around Venus, generating a tiny but measurable aerodynamic torque, or rotation, on the satellite.

This torque can be measured very accurately based on the amount of correction that must be applied by reaction wheels, which counter-rotate inside the spacecraft to maintain its orientation in space.

Mimicking the vanes of a windmill

Starting on Monday, the solar panels rotated through five daily-changing sets of orientations. While one panel remained perpendicular to the direction of flight, the other rotated in steps, gradually increasing the torque to be counter-balanced by the reaction wheels.

On the last day, 16 April, the solar arrays were rotated at plus and minus 45° to the atmospheric flow, mimicking the vanes of a windmill, in order to gather additional information on the behaviour of the molecules of the atmosphere bouncing off the solar wings.

A very capable satellite

"The aerodrag campaign went without problem, and conclusively demonstrated that Venus Express can be securely and accurately used to sense the density of the planet's atmosphere. Venus Express has shown once again that it is a very capable satellite," said Spacecraft Operations Manager Octavio Camino.

Camino explained that the mission operations team will study last week’s results to develop an optimised configuration for aerodrag campaigns in October and in 2011. Aerodrag testing was also conducted in 2008, 2009 and February 2010.


Continued positive results may enable Venus Express to conduct more sophisticated investigations deeper in the atmosphere, which would be of immense interest to planetary scientists.

The solar array on Venus Express comprise two symmetrical wings supporting gallium-arsenide solar cells. Their combined 5.7 sq m can generate up to 1400 W of power in Venus orbit.

Source:- ESA

First Data from CryoSat-2 Successfully Received

Image comment: The CryoSat mission is dedicated to monitoring of the changes in the thickness of marine ice floating in the polar oceans and thickness variations on the ice sheets that overlay Greenland and Antarctica.

Image credits: ESA / AOES Medialab

Experts at the European Space Agency (ESA) announce that one of their control centers has already begun receiving the first datasets from the newly-launched CryoSat-2 satellite. The instrument took off from the Baikonur Cosmodrome, in Kazakhstan, on April 8, and its managers say that it has performed beautifully during the critical stage of the mission. In most satellite launches, the first few days of operations are absolutely critical. Just hours after mission experts turned on the sophisticated radars aboard the spacecraft, they began receiving back telemetry, the ESA team says.

Only a few minutes after being launched last Thursday, the satellite was inserted by its Dnepr delivery system into a polar orbit above Earth. For the next three days, researchers working from the European Space Operations Center (ESOC), in Germany, monitored the payload and health status of the satellite around the clock. The goal was to ensure that everything was fairing along nicely and that no damage had come to either the satellite or its cargo during the harsh conditions of lift-off.

“The satellite is in excellent condition and the mission operations team quickly resolved the few problems that came up. It's been a very smooth entry into orbit, precisely as planned,” said on April 11 Pier Paolo Emanuelli, the Flight Director of ESA. He also announced at the time that the Launch and Early Orbit Phase (LEOP) of the mission had concluded successfully. The main instrument on CryoSat-2, called the Synthetic Aperture Interferometric Radar Altimeter (SIRAL), was turned on late Sunday, and it immediately began picking up echo data from the ground.

The ESA Kiruna ground station picked up on the spacecraft's telemetry shortly afterwards. The first data were collected and processed on-site, before being shipped out to ESA. “We switched SIRAL on and it worked beautifully from the very start. Our first data were taken over the Antarctic's Ross Ice Shelf, and clearly show the ice cover and reflections from underlying layers. These are excellent results at such an early stage and are a tribute to the hard work of the entire CryoSat community,” said the lead investigator of the CryoSat-2 mission, professor Duncan Wingham.

“The combined ground teams proved the value of months of extensive training and preparation and the satellite has shown to be a high-quality machine with very few problems. The launch and orbit injection have been almost flawless and we are looking forward to an extremely productive mission,” concluded the ESA project manager for the mission, Richard Francis.

Baby stars in the Rosette cloud

Infrared image of the Rosette molecular cloud. Herschel collects the infrared light given out by dust and this image is a three-colour composite made of wavelengths at 70 microns (blue), 160 microns (green) and 250 microns (red). It was made with observations from Herschel’s Photoconductor Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE). The bright smudges are dusty cocoons containing massive protostars. The small spots near the centre of the image are lower mass protostars.

Credits: ESA/PACS & SPIRE Consortium/HOBYS Key Programme Consortia

Herschel’s latest image reveals the formation of previously unseen large stars, each one up to ten times the mass of our Sun. These are the stars that will influence where and how the next generation of stars are formed. The image is a new release of ‘OSHI’, ESA’s Online Showcase of Herschel Images.

The Rosette Nebula resides some 5,000 light years from Earth and is associated with a larger cloud that contains enough dust and gas to make the equivalent of 10,000 Sun-like stars. The Herschel image shows half of the nebula and most of the Rosette cloud. The massive stars powering the nebula lie to the right of the image but are invisible at these wavelengths. Each colour represents a different temperature of dust, from –263ºC (only 10ºC above absolute zero) in the red emission to –233ºC in the blue.

The bright smudges are dusty cocoons hiding massive protostars. These will eventually become stars containing around ten times the mass of the Sun. The small spots near the centre and in the redder regions of the image are lower mass protostars, similar in mass to the Sun.

ESA’s Herschel space observatory collects the infrared light given out by dust. This image is a combination of three infrared wavelengths, colour-coded blue, green and red in the image, though in reality the wavelengths are invisible to our eyes. It was created using observations from Herschel’s Photoconductor Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE).

Herschel is showing astronomers such young, massive protostars for the first time, as part of the ‘Herschel imaging survey of OB Young Stellar objects’. Known as HOBYS, the survey targets young OB class stars, which will become the hottest and brightest stars.

“High-mass star-forming regions are rare and further away than low-mass ones,” says Frédérique Motte, Laboratoire AIM Paris-Saclay, France. So astronomers have had to wait for a space telescope like Herschel to reveal them.

It is important to understand the formation of high-mass stars in our Galaxy because they feed so much light and other forms of energy into their parent cloud they can often trigger the formation of the next generation of stars.

When astronomers look at distant galaxies, the star-forming regions they see are the bright, massive ones. Thus, if they want to compare our Galaxy to distant ones they must first understand high-mass star-formation here.

“Herschel will look at many other high-mass star-forming regions, some of them building stars up to a hundred times the mass of the Sun,” says Dr Motte, who plans to present the first scientific results from HOBYS at ESA’s annual ESLAB symposium to be held in the Netherlands, 4–7 May.

Source: ESA

Particles That Form Auroras Finally Observed Directly

Image comment: Image of the auroral oval taken by the IMAGE spacecraft in ultraviolet
Image credits: IMAGE-FUV team / NASA

Researchers at the University College London (UCL), in the United Kingdom, recently managed to observe the energetic particles that form the brightest auroras. This is the first time such a feat was accomplished, and the team behind the research says that their accomplishment was made possible through the use of the Cluster spacecraft. Details of the discovery were presented today, April 12, at the RAS National Astronomy Meeting (NAM2010), in Glasgow, Scotland, AlphaGalileo reports.

The science team that made the observations was led by UCL expert Dr Colin Forsyth, who also presented the findings at the meeting. He explains that auroras are formed as charged particles from the Sun slam into the upper portions of our planet's atmosphere. As this happens, they lose energy, and heat the molecules that exist at high altitudes, making them glow in beautiful red, green and blue nuances. The particles then flow along the Earth's magnetic lines, which is why some of them have a curtain-like appearance. Generally, the auroras can only be seen at the north and south poles.

At a height of 50,000 kilometers (31,000 miles) above the planet, some peculiar processes take place. Particles are accelerated considerably, before they have sufficient energy to excite the auroras. These phenomena are not well understood, and researchers know that they are key to understanding the atmospheric lights themselves. In order to gain more insight into these phenomena, the UCL team used the four identical satellites of the Cluster mission, which is a collaboration of NASA and the European Space Agency (ESA). The constellation was launched 10 years ago, and it orbits the planet in close formation, with one spacecraft trailing closely after the other.

One of Cluster's outstanding features is that is allows experts to create a 3D picture of the magnetosphere, the atmosphere's protective layer, that shields us from cosmic radiation and most solar flares. This is only possible through the multi-point perspective that the four satellites provide. “The Cluster spacecraft have been maneuvered such that one of them was at a higher altitude than the others when they passed over the auroral regions. We were then able to simultaneously measure the particle energies at different heights and thus their acceleration. These exciting new results will give us new insight into the accelerating processes and the transfer of energy from the magnetosphere into the atmosphere,” the team leader said at the meeting.

Venus is alive – geologically speaking

This figure shows the volcanic peak Idunn Mons (at 46°S, 214.5°E) in the Imdr Regio area of Venus. The topography derives from data obtained by NASA’s Magellan spacecraft, with a vertical exageration of 30 times. Radar data (in brown) from Magellan has been draped on top of the topographic data. Bright areas are rough or have steep slopes. Dark areas are smooth.

The coloured overlay shows the heat patterns derived from surface brightness data collected by the visible and infrared thermal imaging spectrometer (VIRTIS) aboard ESA’s Venus Express spacecraft. Temperature variations due to topography were removed. The brightness signals the composition of the minerals that have been changed due to lava flow. Red-orange is the warmest area and purple is the coolest. The warmest area is situated on the summit, which stands about 2.5 km above the plains, and on the bright flows that originate there. Idunn Mons has a diameter of about 200 km.

The VIRTIS data was collected from May 2006 to the end of 2007.

Credits: ESA/NASA/JPL

ESA's Venus Express has returned the clearest indication yet that Venus is still geologically active. Relatively young lava flows have been identified by the way they emit infrared radiation. The finding suggests the planet remains capable of volcanic eruptions.

It has long been recognised that there are simply not enough craters on Venus. Something is wiping the planet's surface clean. That something is thought to be volcanic activity but the question is whether it happens quickly or slowly? Is there some sort of cataclysmic volcanic activity that resurfaces the entire planet with lava, or a gradual sequence of smaller volcanic eruptions? New results suggest the latter.

"Now we have strong evidence right at the surface for recent eruptions," says Sue Smrekar, a scientist at NASA's Jet Propulsion Laboratory in California.

That strong evidence comes in the form of compositional differences compared to the surrounding landscape in three volcanic regions. The data were collected by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on ESA's Venus Express spacecraft, which has been orbiting the planet since April 2006.

VIRTIS records the brightness of surface rocks, providing an estimate of 'emissivity'. In 2008, Jörn Helbert and Nils Müller, Institute of Planetary Research, German Aerospace Center, Berlin and co-authors on this new work, published a map of the variation of infrared emissivity across the southern hemisphere of Venus.

Dr Smrekar and her colleagues targeted three regions that geologically resemble Hawaii, well known for its active volcanism. They show that the regions on Venus have higher emissivities than their surroundings, indicating different compositions.

On Earth, lava flows react rapidly with oxygen and other elements in the atmosphere, changing their composition. On Venus, the process should be similar, though more intense because of the hotter, denser atmosphere, chiefly of carbon dioxide.

The researchers interpret the fact that the lava flows appear to have different compositions from their surroundings as being evidence of a lack of surface weathering, indicating that the flows erupted relatively recently. They estimate that the flows are possibly as geologically recent as 2 500 000 years - and likely much less, possibly even currently active. "This is a significant result," says Hľkan Svedhem, ESA Venus Express Project Scientist.

Whilst the gradual resurfacing scenario might not be the most spectacular, it does make Venus look a little more Earth-like.

"There are some intriguing models of how Venus could have completely covered itself in kilometres of volcanic lava in a short time, but they require that the interior of Venus behaves very differently from Earth. If volcanism is more gradual, this implies that the interior may behave more like Earth, though without plate tectonics," says Dr Smrekar.

Source:- http://www.esa.int/esaCP/SEMUKVZNK7G_index_0.html

ESA Looking at Lunar Lander Mission

Recent investigations by NASA's Lunar Crater Observation and Sensing Satellite (LCROSS) satellite have revealed in late 2009 that massive amounts of water-ice can be found at the lunar south pole. Though the area experiences extremely cold temperatures, and the craters there are among the coolest places in the solar system, researchers and astronomers at the European Space Agency (ESA) are already planning a mission to the location. The flight is scheduled to be unmanned, and the agency plans to put a lander on the surface of the planet's natural satellite in the not-too-distant future, Space Fellowship reports.

More than 40 years ago, Apollo astronauts set foot on the Moon, but at the time they landed in relatively smooth terrain, where there was a lot of room to maneuver. But the future ESA mission will not be so easy to plan and execute. The lunar south pole is an extremely rugged place, with high ridges marking the boundaries of very deep craters, where sunlight hasn't reached the bottom for millions of years. It is in this desolate landscape that ESA officials want to set down a lander, so that it could benefit from the advantages that the presence of ice brings.

At this point, ESA is launching a submissions campaign for proposals on how the Lunar Lander mission should take place. Representatives of the industry are expected to submit their proposals for the vehicles that would take scientific equipment there, as well as for how the entire flight would be set up and organized. There is a vast array of technical problems to consider as well, and the trip is no less dangerous now than it was when the United States sent its manned missions to the Moon. The case of the Apollo 13 mission is still vivid in the mind of many, and experts know that it was only luck, dedication and hard work under extreme stress conditions that saw the three astronauts returning home alive.

According to officials at the agency, there are two goals that proposal submitters need to keep in mind. The first is that the delivery vehicle and the spacecraft itself need to be extremely precise in their navigation instruments, so that they can be landed with extreme accuracy in this difficult terrain. The heavily-cratered terrain is the direct target of the mission. The second objective is for the lander to image the land below as it descends and recognize hazardous terrain using onboard artificial intelligence. Additionally, the spacecraft will need to be able to analyze its location with a large array of scientific instruments.

Water On Jupiter-Like Corot-9b?

The newly discovered gas giant Corot-9b may have an interior that closely resembles those of Jupiter and Saturn in our own Solar System, according to a new paper published today in Nature.

Some evidence also suggest that the exoplanet, discovered last Spring, may also be temperate enough to allow the presence of liquid water.

Corot-9b orbits its star every 95.274 days, a little longer than Mercury takes to go round the Sun. It is the first transiting planet to have both a longer period and a near-circular orbit. Its orbit is slightly elliptical but at closest approach to its parent star it reaches a distance of 54 million kilometers.

Although that is only about the distance of Mercury in our Solar System, it is by far the largest orbit of any transiting planet found so far. Because it orbits a star cooler than our Sun, calculations estimate that Corot-9b's temperature could lie somewhere between -23°C and 157°C.



This is an artist's impression of an exoplanet around a star.

(Photo Credit: ESA (Illustration by AOES Medialab))

The new planet has a radius around 1.05 times that of Jupiter but only 84% of the mass. This leads to a density of 0.90 g/cc, or 68% that of Jupiter. "Corot-9b is the first exoplanet that is definitely similar to a planet in our Solar System," says Hans Deeg, a researcher at the Instituto de Astrofísica de Canarias.

The similarity is caused by the fact that Corot-9b is sufficiently far from its star to prevent tidal forces from heating its interior. Tidal forces are created by the strength of gravity weakening from the front to back of the celestial body. When the difference between the near side and the far side is great, the tidal force can prevent the planet from spinning quickly, forcing it to only show one face to the star. It can also provide heat to the interior of the planet, changing its physical condition.

Based on calculations, neither of these is possible in this case. "Although we don't know, because we can't see the planet directly, there is reason to believe that this planet has a normal day-night cycle," says Malcolm Fridlund, ESA Project Scientist for Corot. It means that lacking a tidal heat source, Corot-9b's interior is likely to have remained similar to the gas giants in our Solar System.

There is also one other tantalizing possibility about this world. Although the planet itself is a gas giant and hence has no solid surface to stand on, what if it possessed a moon like Saturn's Titan? If the temperature were towards the lower end of the estimated range, then any moon would be an ice ball. If it were towards the upper end, it would be rather too hot for liquid water. But what if it were somewhere in the middle?

Citation: Deeg et al., A transiting giant planet with a temperature between 250 K and 430 K', Nature, March 2010, 464, 384-387; doi:10.1038/nature08856

Planck sees tapestry of cold dust

The image spans about 50° of the sky. It is a three-colour combination constructed from Planck’s two highest frequency channels (557 and 857 GHz, corresponding to wavelengths of 540 and 350 micrometres), and an image at the shorter wavelength of 100 micrometres made by the IRAS satellite. This combination visualises dust temperature very effectively: red corresponds to temperatures as cold as 10° above absolute zero, and white to those of a few tens of degrees. Overall, the image shows local dust structures within 500 light-years of the Sun.

Credits: ESA and the HFI Consortium, IRAS

Giant filaments of cold dust stretching through our Galaxy are revealed in a new image from ESA’s Planck satellite. Analysing these structures could help to determine the forces that shape our Galaxy and trigger star formation.

Planck is principally designed to study the biggest mysteries of cosmology. How did the Universe form? How did the galaxies form? This new image extends the range of its investigations into the cold dust structures of our own Galaxy.

	Planck scanning the sky

The image shows the filamentary structure of dust in the solar neighbourhood – within about 500 light-years of the Sun. The local filaments are connected to the Milky Way, which is the pink horizontal feature near the bottom of the image. Here, the emission is coming from much further away, across the disc of our Galaxy.

The image has been colour coded to discern different temperatures of dust. White-pink tones show dust of a few tens of degrees above absolute zero, whereas the deeper colours are dust at around –261°C, only about 12 degrees above absolute zero. The warmer dust is concentrated into the plane of the Galaxy whereas the dust suspended above and below is cooler.

Planck's newly imaged region shown in box

“What makes these structures have these particular shapes is not well understood,” says Jan Tauber, ESA Project Scientist for Planck. The denser parts are called molecular clouds while the more diffuse parts are ‘cirrus’. They consist of both dust and gas, although the gas does not show up directly in this image.

There are many forces at work in the Galaxy to help shape the molecular clouds and cirrus into these filamentary patterns. For example, on large scales the Galaxy rotates, creating spiral patterns of stars, dust, and gas. Gravity exerts an important influence, pulling on the dust and gas. Radiation and particle jets from stars push the dust and gas around, and magnetic fields also play a role, although to what extent is presently unclear.

Bright spots in the image are dense clumps of matter where star formation may take place. As the clumps shrink, they become denser and better at shielding their interiors from light and other radiation. This allows them to cool more easily and collapse faster.

Filamentary structures on large and small scales in the Milky Way

ESA’s Herschel space telescope can be used to study such regions in detail, but only Planck can find them all over the sky. Launched together in May 2009, Planck and Herschel are both studying the coolest components of the Universe. Planck looks at large structures, while Herschel can make detailed observations of smaller structures, such as nearby star-forming regions.

One puzzle to be solved is why there is similar filamentary structure on both the large and the small scale. “That’s a big question,” says Tauber.

The new image is a combination of data taken with Planck’s High Frequency Instrument (HFI), at wavelengths of 540 micrometres and 350 micrometres, and a 100-micrometre image taken in 1983 with the IRAS satellite.

The HFI data were recorded as part of Planck’s first all-sky survey at microwave wavelengths. As the spacecraft rotates, its instruments sweep across the sky. During every rotation, they cross the Milky Way twice. Thus, in the course of Planck’s mission to precisely map the afterglow of the big bang, it is also producing exquisite maps of the Galaxy.

Mars 500 Experiment to Begin Soon

Image comment: The Mars 500 test facility, at the Russian Institute for Biomedical Problems IBMP

Image credits: ESA / RosCosmos

A collaboration between the European Space Agency (ESA) and the Russian Federal Space Agency (RosCosmos) is about to embark on a very ambitious project. Six people are to be locked away in a Russian facility for 520 days, in order to simulate the effects that real astronauts would experience in the case of a return-trip to Mars. With existing technologies, this is the length of time that experts estimate a journey to the Red Planet would take. What the new experiment seeks to accomplish is understand the challenges associated with such an endeavor, but from the “human side” of the argument, ScienceNow reports.

The technology is, oddly enough, just a short distance away from being suitable for such a task, but not the same thing can be said with certainty about humans. There are serious psychological and health issues to consider if you place a crew of 4 to 6 astronauts inside a metal box, and then send them hurtling to another planet. There are space radiation to consider, in addition to solar flares and other such cosmic occurrences. But bacterial infections, claustrophobia and depression can be equally as devastating, and such a long-time journey could easily end in disaster. This is why experiments such as the Mars 500 need to be conducted first.

But the project almost didn't materialize. The costs of hosting the modules that will contain the astronauts for one and a half years at the Russian Institute for Biomedical Problems (IBMP), in Moscow, has not been released. However, sources close to the decision-making process revealed that both ESA and RosCosmos needed to dig deep in their pockets to make it a reality. Now, the four modules that will simulate a Martian transport spacecraft are connected and in place, and the entire program is ready to be set in motion. Six people are competing for a chance to be a part of the experiment, and conditions to be eligible include speaking both Russian and English fluently, as well as advanced training in fields such as medicine, electronics, and other relevant domains.

While inside the experimental modules, the “astronauts” will have no communications to the outside world, other than the one authorized by Mission Control. A delay will also be integrated in the signals traveling from the bogus spacecraft to the control center, simulating the delay that will be incorporated during a real spaceflight, as the distance between the astronauts and Earth increases. The people aboard will also be eating the same freeze-dried food that the crew of the International Space Station (ISS) is currently eating. Basically, every aspect of their lives for 520 days will be subjected to the rigors of a spaceflight.

Phobos Flyby Images: Proposed Landing Sites for the Forthcoming Phobos-Grunt Mission

The High Resolution Stereo Camera (HRSC) onboard the ESA spacecraft Mars Express took this image of the Phobos Grunt landing area using the HRSC nadir channel on 7 March 2010, HRSC Orbit 7915. The image resolution is 4.4m per pixel and the insert marks the proposed landing region and sites for Phobos-Grunt. (Credit: ESA/DLR/FU Berlin (G. Neukum))

Images from the recent flyby of Phobos, on 7 March 2010, have been released. The images show Mars' rocky moon in exquisite detail, with a resolution of just 4.4 metres per pixel. They show the proposed landing sites for the forthcoming Phobos-Grunt mission.

ESA's Mars Express spacecraft orbits the Red Planet in a highly elliptical, polar orbit that brings it close to Phobos every five months. It is the only spacecraft currently in orbit around Mars whose orbit reaches far enough from the planet to provide a close-up view of Phobos.

Like our Moon, Phobos always shows the same side to the planet, so it is only by flying outside the orbit that it becomes possible to observe the far side. Mars Express did just this on 7, 10 and 13 March 2010. Mars Express also collected data with other instruments.

Phobos is an irregular body measuring some 27 × 22 × 19 km. Its origin is debated. It appears to share many surface characteristics with the class of 'carbonaceous C-type' asteroids, which suggests it might have been captured from this population. However, it is difficult to explain either the capture mechanism or the subsequent evolution of the orbit into the equatorial plane of Mars. An alternative hypothesis is that it formed around Mars, and is therefore a remnant from the planetary formation period.

In 2011 Russia will send a mission called Phobos-Grunt (meaning Phobos Soil) to land on the martian moon, collect a soil sample and return it to Earth for analysis.

For operational and landing safety reasons, the proposed landing sites were selected on the far side of Phobos within the area 5°S-5°N, 230-235°E. This region was imaged by the HRSC high-resolution camera of Mars Express during the July-August 2008 flybys of Phobos. But new HRSC images showing the vicinity of the landing area under different conditions, such as better illumination from the Sun, remain highly valuable for mission planners.

It is expected that Earth-based ESA stations will take part in controlling Phobos-Grunt, receiving telemetry and making trajectory measurements, including implementation of very long-baseline interferometry (VLBI). This cooperation is realized on the basis of the agreement on collaboration of the Russian Federal Space Agency and ESA in the framework of the 'Phobos-Grunt' and 'ExoMars' projects.

Mars Express will continue to encounter Phobos until the end of March, when the moon will pass out of range. During the remaining flybys, HRSC and other instruments will continue to collect data.

Adapted from materials provided by European Space Agency

Third ESA ATV Named After Edoardo Amaldi

Image comment: Artist's rendition of the ATV in Earth's orbit

Image credits: ESA / D.Ducros

Once the first flight of the Automated Transfer Vehicle (ATV) Jules Verne completed flawlessly, theEuropean Space Agency (ESA) decided to ramp up production on these unmanned spacecrafts. Their primary goal is to deliver cargo, safe and sound, to the International Space Station. They are a part of the international service fleet that does this, which included the Russian Soyuz and Progress capsules, and the Japanese H-II Transfer Vehicle (HTV). Now, with the second ATV, Johannes Kepler, scheduled for launch later this year, ESA announces the naming of the third cargo capsule.

Officials at the agency decided to name it Edoardo Amaldi, in honor of the famed Italian physicist and space pioneer. “Italy is a key European country in our participation in the ISS partnership. By naming ATV-3 after Edoardo Amaldi, we celebrate a great Italian, but also a committed European who understood the importance of pooling resources and minds together to achieve important results,” said recently in a press conference the ESA Director for Human Spaceflight, Simonetta Di Pippo. Italian Minister of Education, University and Research Sottosegretario Pizza, and the president of the ASI space agency, Enrico Saggese, also participated at the meeting with the media.

“We are paying tribute to a visionary mind, to a great scientist but also to an idea of cooperation that is embodied in the ISS partnership. The ATV is the first recurring production of an exploration spacecraft and places Europe a step closer to our partners. I am glad that Italy is taking so much pride in their participation in the ISS, which is a recognition of their human and industrial capabilities,” the ESA official added, saying that the ATV is currently an indispensable part of the ISS logistics and resupply effort. Over the coming years, as the American space shuttles are retired, its importance will grow even more, as will that of all other unmanned cargo spacecrafts.

“Amaldi was one of the few that in the post-war years prompted into action starting a process leading to the founding of ESRO, and in following of ESA. It is widely acknowledged that since the 1950s the inception of the visionary concept aiming to a unified European capability to explore outer space is largely due to a bunch of prominent European scientists, and Edoardo Amaldi was a leading name among them,” Saggese says.

Why Mars Continuously Loses Atmosphere

According to a new scientific investigation, it would appear that influences from the Sun are directly responsible for why Mars is constantly losing some of its atmosphere to outer space. The research team, which included astrophysicists from the University of Leicester, in the United Kingdom, believes that the star at the center of our solar system may be responsible for emitting large amounts of solar wind pulses, which disturb the Martian atmosphere, and force it to scatter among the stars.

The authors published their new study in a paper appearing in the latest issue of the respected scientific journal Geophysics Research Letters. The investigation was based on datasets collected by the European Space Agency's (ESA) Mars Express missions, but the experts said that they also used some information gathered by a somewhat less known NASA mission called ACE. In charge of the expert team was scientist Niklas Edberg, who was at the time a UL doctoral student, and who is now based at the Swedish Institute for Space Physics (IRF), in Uppsala. Funding for the research came from the EU training Network and the Science and Technology Facilities Council.

The purpose of the study was to analyze the possible correlations between the flux of heavy ions leaving the Martian atmosphere and solar wind data. The experts set out to demonstrate that the two were intimately and directly linked, and they were able to prove this as well. The groups showed that the Martian atmosphere was not escaping the planet in a linear manner, but rather in bursts. These events were found to be synchronized with pulses recorded in solar wind intensity, the team says. This type of solar activity comes from events called corotating interaction regions (CIR).

In these areas, regions of very fast-moving solar winds encounter regions where they move very slowly, and the result of these interactions is a high-pressure pulse that travels away from the Sun, and collides with the planets, moons and asteroids of the solar system. “The main reason it [atmospheric loss] happens at Mars and not at Earth is the lack of a magnetic field produced by the planet, which protects the atmosphere at Earth. One other aspect of this work is that the observations were made during a very quiet period in the eleven year solar cycle and so we would expect the effect of these and other large scale disturbances to be higher at other times in the solar cycle,” the head of the UL Department of Physics and Astronomy, Professor Mark Lester, says.

Bully galaxy rules the neighborhood

This image from the Advanced Camera for Surveys aboard the NASA/ESA Hubble Space Telescope highlights the large and bright elliptical galaxy called ESO 306-17 in the southern sky. In this image, it appears that ESO 306-17 is surrounded by other galaxies but the bright galaxies at bottom left are thought to be in the foreground, not at the same distance in the sky. In reality, ESO 306-17 lies fairly abandoned in an enormous sea of dark matter and hot gas. Researchers are also using this image to search for nearby ultra-compact dwarf galaxies. Ultra-compact dwarfs are mini versions of dwarf galaxies that have been left with only their core due to interaction with larger, more powerful galaxies. Most ultra-compact dwarfs discovered to date are located near giant elliptical galaxies in large clusters of galaxies, so it will be interesting to see if researchers find similar objects in fossil groups.

Located half a billion light-years from Earth, ESO 306-17, is a large, bright elliptical galaxy in the southern sky of a type known as a fossil group. Astronomers use this term to emphasise the isolated nature of these galaxies. However, are they like fossils — the last remnants of a once active community — or is it more sinister than that? Did ESO 306-17 gobble up its next-door neighbours? Gravity brings galaxies together and bigger ones swallow smaller ones. There is evidence that our own Milky Way galaxy has "snacked" on numerous smaller galaxies that strayed too close. ESO 306-17 and other fossil groups may be the most extreme examples of galaxy cannibalism, ravenous systems that don't stop until they've devoured all of their neighbours.

In this image, taken by the Advanced Camera for Surveys aboard Hubble in November 2008, it appears that ESO 306-17 is surrounded by other galaxies, but the bright galaxies at bottom left are thought to be in the foreground, not at the same distance in the sky. In reality, ESO 306-17 lies fairly abandoned in an enormous sea of dark matter and hot gas [1]. When zooming in closely on ESO 306-17, one can see faint clusters of stars through the bright shine of the galaxy's large halo. These are globular clusters — tightly bound groups of stars that can often fend off cannibalism from larger, "bully" galaxies. Studying these surrounding clusters will prove helpful to astronomers in their pursuit to put the pieces of ESO 306-17's history together.

Researchers are also using this image to search for nearby ultra-compact dwarf galaxies. Ultra-compact dwarfs are mini versions of dwarf galaxies that have been left with only their core due to interaction with larger, more powerful galaxies. Most ultra-compact dwarfs discovered to date are located near giant elliptical galaxies in large clusters of galaxies, so it will be interesting to see if researchers find similar objects in fossil groups.

Source: ESA/Hubble Information Centre

Coolest spacecraft ever in orbit around second Lagrange point

On 2 July, the detectors of Planck's High Frequency Instrument reached their amazingly low operational temperature of -273 C, making them the coldest known objects in space. The spacecraft has also just entered its final orbit around the second Lagrange point of the Sun-Earth system, or L2.

Planck is equipped with a passive cooling system that brings its temperature down to about -230 C by radiating heat into space. Three active coolers take over from there, and bring the temperature down further to an amazing low of -273.05 C, only 0.1 C above absolute zero - the coldest temperature theoretically possible in our Universe.

Such low temperatures are necessary for Planck's detectors to study the Cosmic Microwave Background (CMB), the first light released by the universe only 380 000 yrs after the Big Bang, by measuring its temperature across the sky.

The detectors will look for variations in the temperature of the CMB that are about a million times smaller than one degree - this is comparable to measuring from Earth the heat produced by a rabbit sitting on the Moon. This is why the detectors must be cooled to temperatures close to absolute zero ( - 273.15 C, or zero Kelvin, 0K).

Details on the different stages of the cool-down process are available via the 'Planck in depth' link at right.

Starting at 13:15 CEST 2 July, the Planck Mission Control Team conducted a crucial orbit insertion manoeuvre designed to place the satellite into its final orbit about L2.

Once commanded, the burn was auto-controlled by Planck, with the thrusters operating for between 12 and 24 hours. The manoeuvre directed the satellite into its final operational orbit around the second Lagrange point of the Sun-Earth system, L2.

The thruster burn was planned to deliberately underperform by a small margin, necessitating a small 'touch up' manoeuvre in the coming days to bring the satellite fully onto its planned trajectory.

'While this manoeuvre itself is routine, it represents the final major step in the long voyage to L2, and everyone here is quite happy to see Planck getting into its operational orbit,' said Chris Watson, Spacecraft Operations Manager, speaking in the mission's Dedicated Control Room at ESA's European Space Operations Centre, Darmstadt, Germany.

The manoeuvre was planned to change the satellite's speed by 211.6 km/hour, ending with a final speed of 1010 Km/hour with respect to the ground. Together with Earth and the virtual point L2, Planck will then be orbiting the Sun at a speed of 106 254 km/hour (29.5 km/second).

At the start of 2 July's manoeuvre, Planck was located 1.43 million km from Earth.

All commissioning activities are on schedule, and this phase of the mission is practically complete. Over the next few weeks, the operation of the instruments will be fine-tuned for best performance.

Planck will begin to survey the sky in mid-August.

Source: European Space Agency

XMM-Newton discovers a new class of black holes

Illustration of HLX-1 (blue star to the upper left hand side of the galactic bulge). HLX-1, located on the outskirts of the spiral galaxy ESO 243-49, is the strongest candidate to- date of intermediate-mass black holes. Credits: Heidi Sagerud

Astronomers using ESA’s XMM-Newton X-ray observatory have discovered a black hole weighing more than 500 solar masses, a missing link between lighter stellar-mass and heavier supermassive black holes, in a distant galaxy. This discovery is the best detection to date of a new class that has long been searched for: intermediate mass black holes.

Due to appear tomorrow in the journal Nature, the discovery has been made by an international team of researchers working with XMM-Newton data, led by Sean Farrell from the Centre d’Etude Spatiale des Rayonnements, now based at the University of Leicester.

Stellar-mass black holes (about three to twenty times as massive as the Sun) and supermassive black holes (several million to several thousand million times as massive as the Sun) have long been known to exist. Because of the large gap between these two extremes, scientists have speculated the existence of a third, intermediate class of black holes, with masses between a hundred and several hundred thousand solar masses.

Up until now, scientists were unable to confirm that this elusive intermediate class actually existed.


Farrell’s team were analysing archived data obtained by XMM-Newton, looking for neutron stars and white dwarves, when they stumbled upon a most peculiar object that was observed on 23 November 2004.

Called HLX-1 (Hyper-Luminous X-ray source 1), it lies towards the outskirts of the galaxy ESO 243-49, approximately 290 million light-years from Earth. If it is indeed located in this distant galaxy, HLX-1 is very luminous in X-rays; peaking at 260 million times the luminosity of the Sun.

On analysing the light originating from HLX-1, the team found that the X-ray signature was inconsistent with any object other than a feeding black hole. The measured brightness was too low for it to be in our own Galaxy, and the lack of observed radio or optical emission from the location of HLX-1 in addition to the observed X-ray signature indicates that it is unlikely to be a background galaxy.

This means that the source of the X-ray emission must lie in ESO 243-49. Its location is too far away from the galactic centre for it to be a supermassive black hole, and too bright for a stellar-mass black hole feeding at the maximum rate.

To be sure that this really was a single astronomical object, and not a cluster of several fainter sources that was shining brightly, the team used XMM-Newton to observe it again on 28 November 2008.

Comparing the two observations, they found that the signature of X-rays originating from HLX-1 varied significantly in time and concluded from this that it must be a single object. They found that the only way to explain its intense luminosity was if HLX-1 harboured a black hole greater than 500 solar masses. No other physical explanation could account for what they had seen.


The few intermediate-mass black hole candidates that have been discovered so far could be accounted for by other theories, but this one stood out as it was brighter than all the previous candidates by a factor of almost 10. The team had their hands on the best detection of an intermediate mass black holes to-date.

While it is already known that stellar-mass black holes are the remnants of massive stars, how supermassive black holes form is still unknown. One of the possible scenarios involves mergers of intermediate mass black holes. To ratify such a theory, it is essential to prove their existence in the first place.


This is why detections such as this by XMM-Newton are essential. It will help to understand just how supermassive black holes, such as that at the centre of our Galaxy, form.

The team have planned further observations in X-ray, ultraviolet, optical, infrared and radio wavelengths in the near future to better understand this unique object and the environment around it.

Cluster and Double Star: bringing the Sun-Earth connection into focus

Over almost nine years in space, the four Cluster satellites have returned a wealth of science data including insights into improving radio searches for exoplanets, energetic vortices tunnelling into Earth's protective magnetic bubble, and 3D magnetic dances in near-Earth space.

The satellites are in good health as they continue exploring new regions of space.

Launched in 2000, Cluster, the first multi-satellite mission studying near-earth space, is composed of four identical satellites orbiting Earth in a tetrahedral configuration. These satellites are able to study the impact of the Sun on near-Earth space for the first time in 3D.

Flight spares of some of instruments used on Cluster form half the instruments on the Double Star satellites, the two satellites of the first Chinese scientific space mission.

Sounds leaking from Earth's atmosphere

Ten-thousand times more intense than even the strongest military radar signal, Auroral Kilometric Radiation (AKR) is the most powerful emission of terrestrial origin that is beamed into space.

Cluster data helped zero in on theories that comply with observations, showing how this radiation is beamed into space. This new understanding will help astronomers understand the magnetic environment of other planets such as Saturn and Jupiter that also emit AKR, and it will also help them search for similar planets around other stars.

3D view of magnetic reconnection in space

Magnetic reconnection is an important physical phenomenon that is fundamental to star formation, solar explosions and the entry of solar wind energy into the near-Earth environment. With multipoint observations possible only with several satellites, Cluster provided Cluster provided the first 3 D observation of the heart of the reconnection region. The observation helped improve models of magnetic reconnection and a provided a deeper understanding of the process.

Magnetic substorms observed at Jupiter have recently been compared with those that occur at Earth, shedding new light on this phenomenon. This study was based on data obtained with the ESA Cluster and NASA Galileo spacecraft. Credits J. Herting/Max Planck Institut fur Sonnensystem-forschung

Giant plasma vortices at the edge of Earth's magnetosphere

Cluster spotted vortices of superheated gas ejected from the Sun, high above Earth, tunnelling its way into Earth's protective magnetic bubble, the magnetosphere. This discovery solved a 17-year old mystery, showing how the magnetosphere is constantly topped up with electrified gas.

Oscillations of Earth's natural cloak of magnetism

The four Cluster satellites and Double Star TC-1 unexpectedly found themselves engulfed by waves of electrical and magnetic energy as they travelled through Earth's night-time shadow. Something had set the tail of Earth's natural cloak of magnetism oscillating, like waves created by a boat travelling across a lake. The data collected gave scientists an important clue to the effects of space weather on Earth's magnetic field.

First direct measurement of the ring current

The four Cluster satellites obtained the first simultaneous, multipoint current density measurements in the region of the ring current. Scientists have since partially mapped the ring current region under various geomagnetic conditions by analysing five months of data. This information is important to quantify the changes that occur in the ring current (for e.g. the input of particles, amount of current created) as geomagnetic storms develop. This information is important for understanding potential hazards to space-based technology.

As of June 2009, the Cluster and Double Star missions have recorded over 1000 publications in refereed journals.

Building the Soyuz launch facility at Europe’s Spaceport

Activity is continuing at the Guiana Space Centre (Centre Spatial Guyanais – CSG), Europe’s Spaceport in French Guiana, as the Soyuz launch site takes shape. Soyuz is a medium-class launcher and its performance will perfectly complement that of the other ESA launchers, Ariane and Vega.

Horizontal rollout

The horizontal transfer of Soyuz launchers at Europe’s Spaceport in French Guiana will follow the same basic procedures used for Soyuz operations at Baikonur Cosmodrome. The image shows the rollout of the Soyuz FG launcher and Soyuz

TMA-15 spacecraft that lifted off from the cosmodrome on 27 May 2009 with a three-member crew for the International Space Station.

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