Mystery ‘dark flow’ extends towards edge of universe

Mystery ‘dark flow’ extends towards edge of universe – space – 16 November 2009 – New Scientist

SOMETHING big is out there beyond the visible edge of our universe. That’s the conclusion of the largest analysis to date of over 1000 galaxy clusters streaming in one direction at blistering speeds. Some researchers say this so-called “dark flow” is a sign that other universes nestle next door.

Galaxy study hints at cracks in dark matter theories

Galaxy study hints at cracks in dark matter theories – space – 30 September 2009 – New Scientist

The study shows that there is always five times more dark matter than normal matter where the dark matter density has dropped to one-quarter of its central value.
Undiscovered force?

The finding goes against expectations because the ratio of dark to normal matter should depend on the galaxy’s history – for example, whether it has merged with another galaxy or remained isolated during its entire existence. Mergers should skew the ratio of dark to normal matter on an individual basis.

“There is absolutely no rule in physics that explains these results,” says study co-author Hong Sheng Zhao of the University of St Andrews in the UK.

Hubble Gets A New Set Of Eyes

Hubble Gets A New Set Of Eyes – The Picture Show Blog : NPR

A luminous “butterfly” nebula fans out from a dying star, a turbulent cloud of gas and dust gives us a peek at the birth of a constellation, and multi-colored stars fill the frame like a tray of glowing jellybeans. All these dazzling images — and more — come from the newly refurbished Hubble Space Telescope in a collection of photos released today by NASA.

Late light reveals what space is made of

Late light reveals what space is made of – space – 12 August 2009 – New Scientist

As Wagner and his colleagues analysed the data in the weeks and months that followed, an odd pattern emerged. Lower-energy photons from Markarian 501 had outpaced their higher-energy counterparts, arriving up to 4 minutes earlier (Physics Letters B, vol 668, p 253).

This should not happen. If an object is 500 million light years away, light from it always takes 500 million years to get to us, no more, no less. Whatever their energy, photons always travel at the same speed, the implacable cosmic speed limit: the speed of light.

Perhaps the anomaly has a mundane explanation. We do not really understand the processes within objects such as Markarian 501 that accelerate particles to phenomenal energies and catapult them towards us. They are thought ultimately to have something to do with the convulsions of supermassive black holes at the objects’ hearts. It could be that these mechanisms naturally spew out low-energy particles before high-energy ones.

Or they might not. “The more fascinating explanation would be that this delay is not intrinsic to the source, but that it happens along the way from the source to us,” says Wagner.
Quantum signature

What piqued the interest of Wagner and his colleagues was that the MAGIC observations were showing just the sort of effect that quite a few models of quantum gravity predict.

Telescopes poised to spot air-breathing aliens

www.newscientist.com

Scientists announce stunning exoplanet discovery

www.tgdaily.com:
Geneva (Switzerland) – Scientists at the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) claim to have discovered the smallest exoplanet yet: In the accelerating search for a twin of Earth, Gliese 581 e is only 1.9 times the mass of Earth and may have a similar material structure, but it is too close to its host star to support life as we know it.

O planetă „locuibilă” la doar 20,5 ani-lumină

www.gandul.info:
Astronomii de la observatorul din La Silla (Chile) au descoperit o planetă de două ori mai mare decât Pământul care ar putea avea condiţii pentru susţinerea vieţii

Planeta orbitează în jurul stelei sale, Gliese 581, apreciată a fi de 77 de ori mai luminoasă decât Soarele nostru

In a Lonely Cosmos, a Hunt for Worlds Like Ours

www.nytimes.com:
Someday it might be said that this was the beginning of the end of cosmic loneliness.

Presently perched on a Delta 2 rocket at Cape Canaveral is a one-ton spacecraft called Kepler. If all goes well, the rocket will lift off about 10:50 Friday evening on a journey that will eventually propel Kepler into orbit around the Sun. There the spacecraft’s mission will be to discover Earth-like planets in Earth-like places — that is to say, in the not-too-cold, not-too-hot, Goldilocks zones around stars where liquid water can exist.

Quark star may hold secret to early universe

www.newscientist.com:
A NEW kind of star may be lurking in the debris from a nearby supernova explosion. If confirmed, the “quark star” could offer fresh insights into the earliest moments of the universe.

When supernovae explode, they leave behind either a black hole or a dense remnant called a neutron star. However, recent calculations suggest a third possibility: a quark star, which forms when the pressure falls just short of creating a black hole.

Astronomers believe these form after the neutron star stage, when the pressure inside a supernova rises so high the neutrons disintegrate into their constituents – quarks. These form an even denser star than neutrons.

Observing a quark star could shed light on what happened just after the big bang, because at this time, the universe was filled with a dense sea of quark matter superheated to a trillion °C. While some groups have claimed to have found candidate quark stars, no discovery has yet been confirmed.

Now Kwong-Sang Cheng of the University of Hong Kong, China, and colleagues have presented evidence that a quark star formed in a bright supernova called SN 1987A (pictured), which is among the nearest supernovae to have been observed.

The birth of a neutron star is known to be accompanied by a single burst of neutrinos. But when the team examined data from two neutrino detectors – Kamiokande II in Japan and Irvine-Michigan-Brookhaven in the US – they found that SN 1987A gave off two separate bursts. “There is a significant time delay between [the bursts recorded by] these two detectors,” says Cheng. They believe the first burst was released when a neutron star formed, while the second was triggered seconds later by its collapse into a quark star.
….

Herschel and Planck ready for dual launch

www.neowin.net:
The European Space Agency’s Herschel space observatory and Planck space telescope have successfully completed their tests in Europe, and will be flown to the space port in Kourou, French Guiana this week, ready for their launch in April.

Named after 18th Century astronomer William Herschel, the Herschel space observatory will be the biggest telescope mirror in space and capable of viewing wavelength radiation in the far-infrared and sub-millimetre range. In comparison, the Hubble telescope is only capable of viewing light that is visible to the human eye. The Planck space telescope is going to be looking for even longer radiation – microwave radiation.