jul 262013
 
Quasars Influence Galaxy Growth

  Quasars are among the brightest, oldest, most distant, and most powerful objects in the Universe. Powered by massive black holes at the center of most known galaxies, quasars can emit enormous amounts of energy, up to a thousand times the total output of the hundreds of billions of stars in our entire Milky Way. [continue reading]

aug 062012
 
How Accurate are the Models of Star- and Planet Formation?

  Stars form when gravitational forces coalesce the gas and dust in interstellar clouds until the material forms clumps dense enough to become stars. Precisely how this happens, however, is still very uncertain. The infall of matter is probably not symmetric, it may be inhibited by the pressure of very hot radiation around the young [continue reading]

mei 102012
 
Overfed Black Holes Shut Down Galactic Star-Making

  A new study has shown that galaxies with the most powerful, active, supermassive black holes at their cores produce fewer stars than galaxies with less active black holes. Credit: Illustration: NASA/JPL-Caltech Researchers compared infrared readings from the Hershel Space Observatory with X-rays streaming from the active central black holes in a survey of 65 [continue reading]

mei 052012
 
Diagnosing a Supermassive Black Hole Flare

  Black holes can come in a wide range of masses. Some, with only about one solar mass, result from the supernova death of a massive star, while those at the center of galaxies (called supermassive black holes) have millions or even billions of solar masses. Supermassive black holes are relatively famous because they are [continue reading]

apr 292012
 
A New Paradigm for Active Galactic Nuclei

  Seyfert galaxies are similar to normal galaxies like our own Milky Way except in one critical respect: their nuclei are fantastically bright, in extreme instances as luminous as 100 billion suns. Astronomers think that these huge energies are generated in such active galactic nuclei by processes around their massive black holes. Matter, as it [continue reading]

apr 022012
 
How Deep Must Life Hide to be Safe on Europa?

  Jupiter’s icy moon is subject to constant and significant blasts of radiation. A new experiment attempts to determine how deep life must lay beneath the crust in order to survive. This will be important for future missions looking for life on Europa. Considered one of the best potential sources for extraterrestrial life in the [continue reading]