Herschel Detects Gigantic Storms Sweeping Entire Galaxies Clean

With observations from the PACS instrument on board the ESA Herschel space observatory, an international team of scientists led by the Max Planck Institute for Extraterrestrial Physics has found gigantic storms of molecular gas gusting in the centres of many galaxies.

Some of these massive outflows reach velocities of more than 1000 kilometres per second, i.e. thousands of times faster than in terrestrial hurricanes. The observations show that the more active galaxies contain stronger winds, which can blow away the entire gas reservoir in a galaxy, thereby inhibiting both further star formation and the growth of the central black hole. This finding is the first conclusive evidence for the importance of galactic winds in the evolution of galaxies.

In the distant and therefore younger Universe, many galaxies show much more activity than our Milky Way today. In commonly accepted evolutionary scenarios gas-rich galaxies merge, which triggers increased star formation as well as the growth of supermassive black holes at their centres. This increased activity, however, seems to cease fairly suddenly, effectively stalling star formation and further growth of the black hole in as little as a few million years' time. What processes could be responsible for removing all the raw material powering this activity -- around a billion solar masses -- in such a short timespan?

The solution to this riddle could be powerful winds that blow gas outwards from the centre of the galaxy. Powered by newly formed stars, shocks from stellar explosions or by the Black Hole in the galaxy's centre, these storms would remove all the gas supply from the galaxy thereby halting the same mechanisms that produced them in the first place.

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Comet Elenin: Preview of a Coming Attraction

Comet Elenin, was first detected on Dec. 10, 2010 by Leonid Elenin, an observer in Lyubertsy, Russia, who made the discovery "remotely" using the ISON-NM observatory near Mayhill, New Mexico. At the time of the discovery, the comet was about 647 million kilometers from Earth. Over the past four-and-a-half months, the comet has - as comets do - closed the distance to Earth's vicinity as it makes its way closer to perihelion. As of May 4, Elenin's distance is about 274 million kilometers.

"That is what happens with these long-period comets that come in from way outside our planetary system," said Don Yeomans of NASA's Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "They make these long, majestic, speedy arcs through our solar system, and sometimes they put on a great show. But not Elenin. Right now that comet looks kind of wimpy."

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Space Shuttle Endeavour to Launch No Earlier Than May 16

NASA is now aiming to launch the space shuttle Endeavour on its final flight no earlier than May 16 – pushing the mission back another week to give ground crews more time to complete and test repairs to the orbiter.

Top NASA managers met may6th afternoon to assess progress on repairs to failed heaters that caused the agency to call off its first launch attempt on April 29. The heaters protect a crucial power unit, and without them, the unit would likely freeze on orbit and be unable to serve its role as one of three power sources for Endeavour's hydraulic systems during re-entry and landing.

Technicians worked on repairs all week and will continue to test the electrical circuitry that caused the initial postponement of Endeavour's STS-134 mission. Repair work will continue through the weekend, NASA officials said, and mission managers will hold a news briefing on Monday (May 9) to discuss the status of the work.

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Supernova and Star Birth in the Meathook Galaxy

The Meathook Galaxy, or NGC 2442, has a dramatically lopsided shape. One spiral arm is tightly folded in on itself and host to a recent supernova, while the other, dotted with recent star formation, extends far out from the nucleus. The NASA/ESA Hubble Space Telescope and the MPG/ESO 2.2-metre telescope have captured two contrasting views of this asymmetric spiral galaxy.

The Meathook Galaxy, or NGC 2442, in the southern constellation of Volans (The Flying Fish), is easily recognised for its asymmetric spiral arms. The galaxy's lopsided appearance is thought to be due to gravitational interactions with another galaxy at some point in its history -- though astronomers have not so far been able to positively identify the culprit.

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Endeavour's Launch Will Occur No Earlier Than May 10

NASA space shuttle and International Space Station managers met Monday and determined that Tuesday, May 10 is the earliest Endeavour could be launched on the STS-134 mission. That date is success oriented based on preliminary schedules to replace a faulty Load Control Assembly (LCA) box in the orbiter's aft compartment.

Plans are for managers to reconvene Friday to determine a more definite launch date after the box is removed and replaced and the retest of systems has been completed. Space Shuttle Program managers adjusted the date after further evaluating the schedules to change out the box and retest the nine shuttle systems associated with the controller. That work would be followed by the standard closeout of the aft compartment before proceeding into the launch countdown.

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