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Kepler's first view of planet hunting territory

...NASA's Kepler spacecraft has opened its eyes and blinked at the rich star field where it will search for extraterrestrial planets like Earth...

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Four-way cosmic

pile up

...Combining images from space- and ground-based telescopes, astronomers have revealed the first cosmic collision of four separate galaxy clusters...

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Hubble witnesses flaring in black

hole jet

...A flare of matter blasting out from a monster black hole is outshining even the core of its host galaxy, M87...

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Video archive

STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.


STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.


STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

 Full presentation
 Mission film

STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.


Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

 Full coverage

Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

 Launch | Science

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Organic 'Lego' molecules hint at origins of life's building blocks



Posted: 21 April, 2009

An interstellar cloud of gas close to the galactic centre rich in a veritable soup of chemicals has produced its two most complex molecules yet, which are just a step away from organic molecules that are the basis of life as we know it.

Interstellar gas close to the galactic centre is producing large organic molecules. Image: NASA/CXC/UCLA/MIT/M Muno et al.

The results, presented today at the National Astronomy Meeting at the University of Hertfordshire, reveal the discovery of ethyl formate and n-propyl cyanide in the star-forming nebula Sagittarius B2. This star-generating cloud contains enough gas and dust to produce three million Suns, and lies just less than 400 light years from the galactic centre itself.

Finding these molecules, which are the most complex ever found in interstellar space, was not easy for the German and American researchers at the Max Planck Institute for Radio Astronomy, the University of Cologne and Cornell University. The larger a molecule is, the more difficult it is to detect because the emitted radiation is spread out across various emission lines, weakening the signal that was detected by the 30-metre IRAM radio astronomy telescope in Spain.

Nevertheless, their discovery raises hope that molecules such as simple amino acids like glycine could also exist in star-forming nebulae. By running computer simulations, the researchers saw that complex molecules build up like Lego blocks, adding together pre-formed molecules such as methanol, rather than being assembled from scratch around nucleating sites such as dust grains.

"There is no apparent limit to the size of molecules that can be formed by this process, so there's good reason to suspect that even more complex organic molecules to be there, if we can detect them," says Cornell's Robin Garrod.

The implications of the discovery of a fully-fledged amino acid in the interstellar firmament would be profound, telling us that the basic materials of life here on Earth first began out there.