Heavens

Unprecedented 16-year-long study tracks stars orbiting Milky Way black hole

By watching the motions of 28 stars orbiting the Milky Way's most central region with admirable patience and amazing precision, astronomers have been able to study the supermassive black hole lurking there. It is known as "Sagittarius A*" (pronounced "Sagittarius A star"). The new research marks the first time that the orbits of so many of these central stars have been calculated precisely and reveals information about the enigmatic formation of these stars — and about the black hole to which they are bound.

Hubble finds carbon dioxide on an extrasolar planet

The Jupiter-sized planet, called HD 189733b, is too hot for life. But new Hubble observations are a proof-of-concept demonstration that the basic chemistry for life can be measured on planets orbiting other stars. Organic compounds can also be a by-product of life processes and their detection on an Earth-like planet may someday provide the first evidence of life beyond Earth.

Previous observations of HD 189733b by Hubble and the Spitzer Space Telescope found water vapour. Earlier this year Hubble found methane in the planet's atmosphere.

Predicted planet seen -- first since Neptune 162 years ago

In 2006, astronomer Alice Quillen of the University of Rochester predicted that a planet of a particular size and orbit must lie within the dust of a nearby star. That planet has now been photographed by the Hubble Space Telescope, making it only the second planet ever imaged after an accurate prediction. The only other planet seen after an accurate prediction was Neptune, discovered more than 160 years ago.

Students discover unique planet

The students were testing a method of investigating the light fluctuations of thousands of stars in the OGLE database in an automated way. The brightness of one of the stars was found to decrease for two hours every 2.5 days by about one percent. Follow-up observations, taken with ESO's Very Large Telescope in Chile, confirmed that this phenomenon is caused by a planet passing in front of the star, blocking part of the starlight at regular intervals.

NASA's Swift looks to comets for a cool view

NASA's Swift Gamma-ray Explorer satellite rocketed into space in 2004 on a mission to study some of the highest-energy events in the universe. The spacecraft has detected more than 380 gamma-ray bursts, fleeting flares that likely signal the birth of a black hole in the distant universe. In that time, Swift also has observed 80 exploding stars and studied six comets.

Comets? ... Comets are "dirty snowballs" made of frozen gases mixed with dust. X-rays come from superhot plasmas. What do cold comets have in common with exploding stars or the birth of black holes?

ESA satellites flying in formation

Based on the outstanding success of the first tandem mission between ERS-2 and Envisat last year, ESA has paired the two satellites together again to help improve our understanding of the planet.

ERS-2, ESA's veteran spacecraft, and Envisat, the largest environmental satellite ever built, both carry Synthetic Aperture Radar (SAR) instruments that provide high resolution images of the Earth's surface.

Brown dwarfs do form like stars

Astronomers have uncovered strong evidence that brown dwarfs form like stars. Using the Smithsonian's Submillimeter Array (SMA), they detected molecules of carbon monoxide shooting outward from the object known as ISO-Oph 102. Such molecular outflows typically are seen coming from young stars or protostars. However, this object has an estimated mass of 60 Jupiters, meaning it is too small to be a star. Astronomers have classified it as a brown dwarf.

Omega Centauri -- the glittering giant of the southern skies

Sparkling away at magnitude 3.7 and appearing nearly as large as the full moon on the southern night sky, Omega Centauri is visible with the unaided eye from a clear, dark observing site. Even through a modest amateur telescope, the cluster is revealed as an incredible, densely packed sphere of glittering stars. But astronomers need to use the full power of professional telescopes to uncover the amazing secrets of this beautiful globular cluster.

Chandrayaan-1 starts observations of the moon

The Indian Space Research Organisation's lunar orbiter Chandrayaan-1 released a probe that impacted close to the lunar south pole on 14 November. Following this, the instruments on the spacecraft are being switched on to get the science observations started.

Jupiter's rocky core bigger and icier, according to new simulation

Berkeley -- Jupiter has a rocky core that is more than twice as large as previously thought, according to computer calculations by a University of California, Berkeley, geophysicist who simulated conditions inside the planet on the scale of individual hydrogen and helium atoms.

The results were published Nov. 20 in Astrophysical Journal Letters.

Hubble captures outstanding views of mammoth stars

The image shows a pair of colossal stars, WR 25 and Tr16-244, located within the open cluster Trumpler 16. This cluster is embedded within the Carina Nebula, an immense cauldron of gas and dust that lies approximately 7500 light-years from Earth. The Carina Nebula contains several ultra-hot stars, including these two star systems and the famous blue star Eta Carinae, which has the highest luminosity yet confirmed. As well as producing incredible amounts of heat, these stars are also very bright, emitting most of their radiation in the ultraviolet and appearing blue in colour.

'Missing link' galaxies discovered

Astronomers at The University of Nottingham have identified a type of galaxy that could be the missing link in our understanding of galaxy evolution.

The STAGES study led by the University's Centre for Astronomy and Particle Theory examines galaxy evolution using images from the Hubble Space Telescope. A separate project — Galaxy Zoo — uses volunteers from the general public to classify galaxies. Both teams have identified a population of unusual red spiral galaxies that are setting out on the road to retirement after a lifetime of forming stars.

Chandrayaan-1 starts observations of the Moon

The Indian Space Research Organisation's lunar orbiter Chandrayaan-1 released a probe that impacted close to the lunar south pole on 14 November. Following this, the instruments on the spacecraft are being switched on to get the science observations started.

Mystery of missing hydrogen

Something vital is missing in the far distant reaches of the Universe: hydrogen - the raw material for stars, planets and possible life.

The discovery of its apparent absence from distant galaxies by a teamof Australian astronomers is puzzling because hydrogen gas is the mostcommon constituent of normal matter in the Universe.

If anything, hydrogen was expected to be more abundant so early in thelife of the Universe because it had not yet been consumed by theformation of all the stars and galaxies we know today.

Los Alamos observatory fingers cosmic ray 'hot spots'

A Los Alamos National Laboratory cosmic-ray observatory has seen for the first time two distinct hot spots that appear to be bombarding Earth with an excess of cosmic rays. The research calls into question nearly a century of understanding about galactic magnetic fields near our solar system.

Joining an international team of collaborators, Los Alamos researchers Brenda Dingus, Gus Sinnis, Gary Walker, Petra Hüntemeyer and John Pretz published the findings today in Physical Review Letters.