New Hubble and Chandra observations of the cluster known as MACSJ0025.4-1222 indicate that a titanic collision has separated dark from ordinary matter. This provides independent confirmation of a similar effect detected previously in a target dubbed the Bullet Cluster, showing that the Bullet Cluster is not an anomalous case.
WASHINGTON -- NASA's newest observatory, the Gamma-Ray Large Area Space Telescope, or GLAST, has begun its mission of exploring the universe in high-energy gamma rays. The spacecraft and its revolutionary instruments passed their orbital checkout with flying colors.
NASA announced today that GLAST has been renamed the Fermi Gamma-ray Space Telescope. The new name honors Prof. Enrico Fermi (1901 - 1954), a pioneer in high-energy physics.
WASHINGTON, D.C. – The U.S. Department of Energy (DOE) and NASA announced today that the Gamma-Ray Large Area Space Telescope (GLAST) has revealed its first all-sky map in gamma rays. The onboard Large Area Telescope's (LAT) all-sky image—which shows the glowing gas of the Milky Way, blinking pulsars and a flaring galaxy billions of light-years away—was created using only 95 hours of "first light" observations, compared with past missions which took years to produce a similar image.
How do galaxies form? The most widely accepted answer to this fundamental question is the model of 'hierarchical formation', a step-wise process in which small galaxies merge to build larger ones. One can think of the galaxies forming in a similar way to how streams merge to form rivers, and how these rivers, in turn, merge to form an even larger river. This theoretical model predicts that massive galaxies grow through many merging events in their lifetime. But when did their cosmological growth spurts finish? When did the most massive galaxies get most of their mass?
NGC 1275 is one of the closest giant elliptical galaxies and lies at the centre of the Perseus Cluster of galaxies. It is an active galaxy, hosting a supermassive black hole at its core, which blows bubbles of radio-wave emitting material into the surrounding cluster gas. Its most spectacular feature is the lacy filigree of gaseous filaments reaching out beyond the galaxy into the multi-million degree X-ray emitting gas that fills the cluster.
A new report from the National Research Council, A CONSTRAINED SPACE EXPLORATION TECHNOLOGY PROGRAM: A REVIEW OF NASA'S EXPLORATION TECHNOLOGY DEVELOPMENT PROGRAM, looks at the quality of technological research conducted at NASA and determines how well-aligned it is with President Bush's Vision for Space Exploration. Specifically, the report examines the degree to which technology development at NASA includes exploration beyond the Moon.
During Hubble's 100 000th orbit around the Earth it peered into a small portion of the nebula near the star cluster NGC 2074 (upper, left). The region is a firestorm of raw stellar creation, perhaps triggered by a nearby supernova explosion. It lies about 170 000 light-years away near the Tarantula nebula, one of the most active star-forming regions in our Local Group of galaxies.
We don't have spacecraft to take us outside our solar system--not yet, at least. Still, astronomers thought they had a pretty good understanding of how our solar system formed and in turn, how others formed. In the last dozen years, nearly 300 exoplanets have been discovered. Are the solar systems in which they reside indeed like our own? Without knowledge or observations to the contrary, conventional knowledge said yes. Three Northwestern University researchers questioned that assumption and explored this question.
EVANSTON, Ill. --- Prevailing theoretical models attempting to explain the formation of the solar system have assumed it to be average in every way. Now a new study by Northwestern University astronomers, using recent data from the 300 exoplanets discovered orbiting other stars, turns that view on its head.
The solar system, it turns out, is pretty special indeed. The study illustrates that if early conditions had been just slightly different, very unpleasant things could have happened -- like planets being thrown into the sun or jettisoned into deep space.