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An ice sheet on the move

Copyright ESA

A huge network of glaciers, carrying ice thousands of kilometres across Antarctica, has been discovered as a result of space agencies’ efforts to focus their satellites on Earth’s icy regions during the International Polar Year. These new findings are critical to understanding sea-level rise.

The International Polar Year (IPY) was an ambitious science programme carried out in 2007 and 2008. Involving more than 60 countries, this large-scale campaign yielded an unprecedented wealth of information about the polar regions, much of which is being used to examine the relationship between these fragile environments and climate.

By joining forces and coordinating their various satellites to optimise data acquisitions, space agencies around the world played a crucial role in IPY.

Carefully piecing together billions of radar data points that were collected over Antarctica by satellites such as ESA’s Envisat, the Canadian Space Agency’s (CSA) Radarsat and Japan Aerospace Exploration Agency’s (JAXA) ALOS, a team of scientists has created the first map of ice motion over the entire continent of Antarctica – and made some astonishing discoveries.

18-Aug-2011

First Solar Sail NanoSail-D Deploys in Low-Earth Orbit

Engineers at NASA’s Marshall Space Flight Center in Huntsville, Ala., confirmed that the NanoSail-D nanosatellite deployed its 100-square-foot polymer sail in low-Earth orbit and is operating as planned. Actual deployment occurred on Jan. 20 at 10 p.m. EST and was confirmed today with beacon packets data received from NanoSail-D and additional ground-based satellite tracking assets. In addition, the NanoSail-D orbital parameter data set shows an appropriate change which is consistent with sail deployment.

“This is tremendous news and the first time NASA has deployed a solar sail in low-Earth orbit,” said Dean Alhorn, NanoSail-D principal investigator and aerospace engineer at the Marshall Center. “To get to this point is an incredible accomplishment for our small team and I can’t thank the amateur ham operator community enough for their help in tracking NanoSail-D. Their assistance was invaluable. In particular, the Marshall Amateur Radio Club was the very first to hear the radio beacon. It was exciting!”

NanoSail-D will continue to send out beacon signals until the onboard batteries are expended and can be found at 437.270 MHz. It can be tracked on the NanoSail-D dashboard at: http://nanosaild.engr.scu.edu/dashboard.htm.

It is estimated that NanoSail-D will remain in low-Earth orbit between 70 and [...]

Romania accedes to ESA Convention

Copyright ESA

Romania took a step further in its relations with ESA by signing the Accession Agreement to the ESA Convention on 20 January 2011, to become the 19th ESA Member State.

The signing ceremony took place at the Romanian Ministry of Foreign Affairs in Bucharest, with the participation of Jean-Jacques Dordain, ESA Director General, Teodor Baconschi, Minister of Foreign Affairs, and Marius-Ioan Piso, President and CEO of the Romanian Space Agency. Other government officials and personalities attended the ceremony, including cosmonaut Dumitru Dorin Prunariu, member of the Board of the Romanian Space Agency.

Romania has a long aerospace tradition and has contributed to more than 30 scientific and technological space missions. During the 1970s and 1980s, Romania was an active member of the Soviet Union’s Interkosmos programme to involve fellow socialist nations in space exploration.

Romania’s cooperation with ESA is long-standing. In 1992, Romania was one of the first Eastern European countries to sign a Cooperation Agreement in the field of the peaceful use of outer space with ESA, paving the way for Romanian participation in several research projects with other European countries. Cooperation between ESA and Romania was strengthened further in October 1999 with the signing [...]

ESA unveils latest map of world’s land cover

ESA unveils latest map of world’s land cover

Copyright ESA

ESA’s 2009 global land cover map has been released and is now available to the public online from the ‘GlobCover’ website. GlobCover 2009 proves the sharpest possible global land cover map can be created within a year.

The map was produced using 12 months of data from Envisat’s Medium Resolution Imaging Spectrometer at a resolution of 300 m.

ESA and Belgium’s Université catholique de Louvain created the map using software developed by Medias France and Germany’s Brockmann Consult on data collected from 1 January to 31 December 2009. GlobCover 2009 was generated within a year of acquiring the final satellite data.

The map’s legend uses the UN Food and Agriculture Organisation’s Land Cover Classification System.

Some 8000 people have downloaded the previous version, GlobCover 2005. These maps are useful for studying the effects of climate change, conserving biodiversity and managing natural resources.

NASA Probe Sees Solar Wind Decline

Copyright NASA

The 33-year odyssey of NASA’s Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind.

Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the sun, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the sun has slowed to zero. Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars.

The event is a major milestone in Voyager 1′s passage through the heliosheath, the turbulent outer shell of the sun’s sphere of influence, and the spacecraft’s upcoming departure from our solar system.

“The solar wind has turned the corner,” said Ed Stone, Voyager project scientist based at the California Institute of Technology in Pasadena, Calif. “Voyager 1 is getting close to interstellar space.”

Our sun gives off a stream of charged particles that form a bubble known as the heliosphere around our solar system. The solar wind travels at supersonic speed until it crosses a shockwave called the termination shock. At this point, the solar [...]

Simulating the formation-flying future of space

Copyright ESA

All space missions are difficult. Docking a pair of spacecraft is tough but flying multiple satellites together in formation is the real cutting edge.

A new simulator is now allowing mission planners to get to grips with multi-satellite missions to come, starting with ESA’s Proba-3.

Several space agencies are preparing formation-flying missions, but it is hard to overstate the difficulty they face: separate expensive pieces of hardware, each one zipping through space at several kilometres per second, may have to manoeuvre to within metres of each other to achieve their goals.

The relative positions of the satellites must be maintained precisely as they close in: lose control of one part of the formation, even momentarily, and the satellites risk destruction. And orbital dynamics dictate the satellites’ orbits will tend to cross as they circle Earth, another worrying factor for their controllers.

Even so, there are specific tasks only formation flying can do – and a new computing resource should help to achieve them.

The Formation Flying Test Bed is a suite of software running across linked computers to simulate all aspects of a formation-flying mission. Overseen by ESA’s Software Systems division at the agency’s ESTEC space [...]

Rosetta lines up for spectacular asteroid flyby

Copyright ESA

Asteroid Lutetia is growing larger in Rosetta’s view as the ESA spacecraft zooms in for a spectacular flyby at 18:10 CEST today. Lutetia is the largest asteroid ever visited by a spacecraft.

Rosetta is perfectly lined up to skim by at a distance of 3162 km, close enough to enable detailed scientific investigations of its surface and environment. The spacecraft is expected to pass Lutetia at a relative speed of 54 000 km/h, when both are some 454 million km from Earth.

As Lutetia is a major scientific target of Rosetta’s mission, most of the orbiter and comet lander instruments will be on for flyby, studying the asteroid’s surface, dust cloud, exosphere, magnetic field, mass and density.

Although most scientific observations will be performed in the next few hours, several instruments have been switched on for several days and will continue observing in the hours after flyby.

The OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) camera has already started acquiring images that show surface details not visible from ground telescopes.

Planck unveils the Universe – now and then

Copyright ESA

ESA’s Planck mission has delivered its first all-sky image. It not only provides new insight into the way stars and galaxies form but also tells us how the Universe itself came to life after the Big Bang.

“This is the moment that Planck was conceived for,” says ESA Director of Science and Robotic Exploration, David Southwood. “We’re not giving the answer. We are opening the door to an Eldorado where scientists can seek the nuggets that will lead to deeper understanding of how our Universe came to be and how it works now. The image itself and its remarkable quality is a tribute to the engineers who built and have operated Planck. Now the scientific harvest must begin.”

From the closest portions of the Milky Way to the furthest reaches of space and time, the new all-sky Planck image is an extraordinary treasure chest of new data for astronomers.

The main disc of our Galaxy runs across the centre of the image. Immediately striking are the streamers of cold dust reaching above and below the Milky Way. This galactic web is where new stars are being formed, and Planck has found many locations where individual stars [...]

Rocky mounds and a plateau on Mars

Copyright ESA

When Mars Express set sail for the crater named after Portuguese navigator Ferdinand Magellan, it found a windblown plateau and mysterious rocky mounds nearby.

Stretching across 190 x 112 km, this region of Mars covers an area of about 21 280 sq km, which is roughly the size of Slovenia. It is located to the southwest of the volcanic region Tharsis on the southern highlands of Mars, near the crater Magellan.

Named after the famous Portuguese navigator and explorer Ferdinand Magellan, the impact crater is about 100 km across. Only a small portion of the crater rim is visible in this image, sitting at the lower right, because the Mars Express High-Resolution Stereo Camera (HRSC) has zeroed in on some intriguing features nearby.

In the west of this region (at the upper edge of the main image) there are light-coloured, irregular protrusions. These features are up to 2 km tall and are probably large rock fragments or mounds of rock. However, their formation is still debated.

One possibility is that the top layer of rock was shattered by the shockwaves from an impact. Another possible explanation would be from a process called subrosion. On [...]

Voyager 2 at 12,000 Days: The Super-Marathon Continues

Copyright NASA

NASA’s plucky Voyager 2 spacecraft has hit a long-haul operations milestone today (June 28) — operating continuously for 12,000 days. For nearly 33 years, the venerable spacecraft has been returning data about the giant outer planets, and the characteristics and interaction of solar wind between and beyond the planets. Among its many findings, Voyager 2 discovered Neptune’s Great Dark Spot and its 450-meter-per-second (1,000-mph) winds.

The two Voyager spacecraft have been the longest continuously operating spacecraft in deep space. Voyager 2 launched on August 20, 1977, when Jimmy Carter was president. Voyager 1 launched about two weeks later on Sept. 5. The two spacecraft are the most distant human-made objects, out at the edge of the heliosphere — the bubble the sun creates around the solar system. Mission managers expect Voyager 1 to leave our solar system and enter interstellar space in the next five years or so, with Voyager 2 on track to enter interstellar space shortly after that.

Having traveled more than 21 billion kilometers (13 billion miles) on its winding path through the planets toward interstellar space, the spacecraft is now nearly 14 billion kilometers (9 billion miles) from the sun. A signal from [...]