Vampire stars suck life from their neighbours

Star V838 Monocerotis's (V838 Mon) light echo, which is about six light years in diameter, is seen from the Hubble space telescope in this in this February 2004 handout photo released by NASA. It became the brightest star in the Milky Way Galaxy in January 2002 when its outer surface greatly expanded suddenly.  An international team of astronomers has spotted a strange phenomena called as vampire stars, where a smaller companion star sucks matter off the surface of its larger neighbour using the very large telescope in Chile. They looked at what are known as O-type stars, which have very high temperature, mass and brightness. These stars have short and violent lives and play a key role in the evolution of galaxies. “These stars are absolute behemoths. They have 15 or more times the mass of our Sun and can be up to a million times brighter. These stars are so hot that they shine with a brilliant blue-white light and have surface temperatures over 30,000C,” the Daily Mail quoted Hugues Sana, from the University of Amsterdam, Netherlands, who is the lead author of the study, as saying. The astronomers studied a sample of 71 O-type single stars and stars in pairs (binaries) in six nearby young star clusters in the Milky Way. Most of the observations in their study were obtained using ESO telescopes, including...

Read More........→January 31, 2013

Biggest Black Hole Blast Discovered (Material Ejected from Quasar SDSS J1106 1939)

This artist’s impression shows the material ejected from the region around the supermassive black hole in the quasar SDSS J1106+1939. This object has the most energetic outflows ever seen, at least five times more powerful than any that have been observed to date. Quasars are extremely bright galactic centers powered by supermassive  black holes. Many blast huge amounts of material out into their host galaxies, and these outflowsplay a key role in the evolution of galaxies. But, before this object was studied, the observed outflows weren’t as powerful as predicted by theorists. The very bright quasar appears at the center of the picture and the outflow spreads about 1000 light-years out into the surrounding galaxy. Illustration credit: ESO/L. Calçada, Note: For more information, see Biggest Black Hole Blast Discovered.Source: Mine...

Read More........→January 17, 2013

Greedy Black Hole Discovered in Andromeda. (A New ULX in Messier 31)

This image shows the Andromeda galaxy (also known as M31) as seen in X-rays with ESA's XMM-Newton space observatory (shown here in red, green, blue and white, according to the energy of the different sources). This X-ray view is combined with an image of Andromeda taken with ESA's Herschel space observatory at far-infrared wavelengths (shown here in grey). Amongst the hundreds of X-ray sources revealed by XMM-Newton in Andromeda are: novae - binary systems comprising a white dwarf accreting material from a companion star; X-ray binaries - binary systems hosting a neutron star or a black hole accreting material from a companion star; and supernova remnants. The sequence of images at the top depict the center of Andromeda and were taken with XMM-Newton on four occasions during 2012. These images illustrate the discovery of a new source, XMMU J004243.6+412519 (highlighted with a circle). XMMU J004243.6+412519 was first detected on 15 January 2012 within an XMM-Newton survey of Andromeda, designed to study the X-ray source population of this galaxy with particular emphasis on novae. On 21 January 2012, XMM-Newton recorded a significant brightening of this source; with a luminosity in excess of 1039 erg/s, it was classified as an ultra-luminous X-ray source, or ULX. This is only the second ULX known in the Andromeda galaxy. The source...

Read More........→January 15, 2013

40 Billion Times More Massive Than Our Sun: Record Setting Supermassive Black Hole

Credit: X-ray: NASA/CXC/Stanford/Hlavacek-Larrondo, J. et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA  Some of the biggest black holes in the Universe may actually be even bigger than previously thought, according to a study using data from NASA's Chandra X-ray Observatory. Astronomers have long known about the class of the largest black holes, which they call "supermassive" black holes. Typically, these black holes, located at the centers of galaxies, have masses ranging between a few million and a few billion times that of our sun. This new analysis has looked at the brightest galaxies in a sample of 18 galaxy clusters, to target the largest black holes. The work suggests that at least ten of the galaxies contain an ultramassive black hole, weighing between 10 and 40 billion times the mass of the sun. Astronomers refer to black holes of this size as "ultramassive" black holes and only know of a few confirmed examples. "Our results show that there may be many more ultramassive black holes in the universe than previously thought," said study leader Julie Hlavacek-Larrondo of Stanford University and formerly of Cambridge University in the UK. The researchers estimated the masses of the black holes in the sample by using an established relationship between masses of black holes, and the amount of...

Read More........→December 20, 2012

NASA to hunt "black holes" with NuSTAR

NASA will study black holes and supernovae using its new spectroscopic telescope (NuSTAR) that is slated to travel to orbit on June 13. It’s the first telescope capable of studying light in the high-energy, short-wavelength X-ray range. Its sensitivity is 100 times higher than that of its predecessors. Complete with images sent back by the Hubble Spitzer and Chandra telescopes, surveillance data from the new “space eye” with the operational lifespan of five years will give scientists an insight into how black holes are born. Source: Voice of Russi...

Read More........→October 08, 2012