Heavens

NASA's Galaxy Evolution Explorer has spotted an amazingly long comet-like tail behind a star streaking through space at supersonic speeds. The star, named Mira after the Latin word for "wonderful," has been a favorite of astronomers for about 400 years. It is a fast-moving, older star called a red giant that sheds massive amounts of surface material.

Four galaxies are slamming into each other and kicking up billions of stars in one of the largest cosmic smash-ups ever observed.

The clashing galaxies, spotted by NASA's Spitzer Space Telescope and the WIYN Telescope, will eventually merge into a single, behemoth galaxy up to 10 times as massive as our own Milky Way. This rare sighting provides an unprecedented look at how the most massive galaxies in the universe form.

Using ESO's Very Large Telescope Interferometer, astronomers from France and Brazil have detected a huge cloud of dust around a star. This observation is further evidence for the theory that such stellar puffs are the cause of the repeated extreme dimming of the star.

ESA’s Venus Express and NASA’s MESSENGER looked at Venus in tandem for a few hours in June. Here is the first set of images.

A unique set of observations, obtained with ESO's VLT, has allowed astronomers to find direct evidence for the material that surrounded a star before it exploded as a Type Ia supernova. This strongly supports the scenario in which the explosion occurred in a system where a white dwarf is fed by a red giant.

Dr. Giovanna Tinetti ( read her interview with Scientific Blogging's Douglas Blane here ) of the European Space Agency and UCL’s Department of Physics & Astronomy has discovered that a planet passing in front of its ‘sun’ absorbs starlight in a way that can only be explained by the presence of water vapour in its atmosphere. This is the first time that astronomers have been able to confirm that water is present on an extra-solar planet.

One year after the beginning of its scientific operations, the high-capability infrared satellite AKARI continues to produce stunning views of the infrared Universe.

Launched in February 2006, AKARI is making a comprehensive, multi-wavelength study of the sky in infrared light, helping to gain a deeper understanding of the formation and evolution of galaxies, stars and planetary systems. The mission is a Japan Aerospace Exploration Agency (JAXA) project with ESA and international participation.

Using natural ‘gravitational lenses’, an international team of astronomers claim to have found a hint of a population of the most distant galaxies yet seen - the light we see from them today left more than 13 thousand million years ago, when the Universe was just 500 million years old.

Computer graphics researchers at Carnegie Mellon University have developed systems for editing or altering photographs using segments of the millions of images available on the Web.

Whether adding people or objects to a photo, or filling holes in an edited photo, the systems automatically find images that match the context of the original photo so they blend realistically. Unlike traditional photo editing, these results can be achieved rapidly by users with minimal skills.

Looking at the chemical composition of stars that host planets, astronomers have found that while dwarf stars often show iron enrichment on their surface, giant stars do not. The astronomers think that the planetary debris falling onto the outer layer of the star produces a detectable effect in a dwarf star, but this pollution is diluted by the giant star and mixed into its interior.

"It is a little bit like a Tiramisu or a Capuccino," says Luca Pasquini from ESO, lead-author of the paper reporting the results. "There is cocoa powder only on the top!'

NASA's Cassini spacecraft has revealed for the first time surface details of Saturn's moon Hyperion, including cup-like craters filled with hydrocarbons that may indicate more widespread presence in our solar system of basic chemicals necessary for life.

Hundreds of thousands of vibrant blue and red stars are visible in this new image of galaxy NGC 4449 taken by the NASA/ESA Hubble Space Telescope. Hot bluish white clusters of massive stars are scattered throughout the galaxy, interspersed with numerous dustier reddish regions of current star formation. Massive dark clouds of gas and dust are silhouetted against the flaming starlight.

Massive Jupiter is undergoing dramatic atmospheric changes that have never been seen before with the keen "eye" of NASA's Hubble Space Telescope.

Jupiter's turbulent clouds are always changing as they encounter atmospheric disturbances while sweeping around the planet at hundreds of miles per hour. But these Hubble images reveal a rapid transformation in the shape and color of Jupiter's clouds near the equator, marking an entire face of the globe.

NASA’s Chandra X-ray Observatory has revealed an X-ray jet blasting away from a neutron star in a binary system. This discovery may help astronomers understand how neutron stars as well as black holes can generate powerful beams of relativistic particles.

The jet was found in Circinus X-1, a system where a neutron star is in orbit around a star several times the mass of the Sun, about 20,000 light years from Earth. A neutron star is an extremely dense remnant of an exploded star consisting of tightly packed neutrons.

Satellite tracking software freely available on the Internet and a smattering of textbook physics could be used by any organisation that can get hold of an intermediate range rocket to mount an unsophisticated attack on military or civilian satellites. Such an attack would require modest engineering capability and only a limited budget.