Slacker Astronomy A supermassive star, all alone A visible/infrared composite view of the Tarantula, with VFTS 682 at its centre. (Image: ESO/M.-R. The Tarantula Nebula is a gift that keeps on giving – if you’re into really massive stars, that is. Some of the region’s clusters contain the most massive stars we know today. The most massive stars form almost exclusively in clusters, as the clouds they form out of have to be so massive that many smaller stars are inevitably born in the process. Some scientists even propose that the combined winds from supermassive clusters like R136 could even be responsible for blasting heavy elements out of their galaxies entirely, into the intergalactic medium. The newly discovered behemoth star , named VFTS 682, is around a million times more luminous than the Sun, and around 150 times as massive. Our current modes of how massive stars form have no way of explaining the formation of a 150 solar star all on its own. References Joachim M. Norman Murray, Brice Ménard, & Todd A.
Bienvenidos a GEDRAA (Grupo de Estrellas Dobles RAA)) Home Page 'Zombie' stars "Zombie" stars that explode like bombs as they die, only to revive by sucking matter out of other stars. According to an astrophysicist at UC Santa Barbara, this isn't the plot for the latest 3D blockbuster movie. Instead, it's something that happens every day in the universe - something that can be used to measure dark energy. This special category of stars, known as Type Ia supernovae, help to probe the mystery of dark energy, which scientists believe is related to the expansion of the universe. Andy Howell, adjunct professor of physics at UCSB and staff scientist at Las Cumbres Observatory Global Telescope (LCOGT), wrote a review article about this topic, published recently in Nature Communications. LCOGT, a privately funded global network of telescopes, works closely with UCSB. Supernovae are stars that have been observed since 1054 A.D., when an exploding star formed the crab nebula, a supernova remnant. "That's what our sun will be at the end of its life," he said.
Últimas noticias Astronomy Picture of the Day “Impossible” Star Exists in Cosmic Forbidden Zone Want to stay on top of all the space news? Follow @universetoday on Twitter This ancient star, in the constellation of Leo (The Lion), is called SDSS J102915+172927 and has been found to have the lowest amount of elements heavier than helium of all stars yet studied. It has a mass smaller than that of the Sun and is probably more than 13 billion years old. Astronomers say a newly found star should not exist and is in the “forbidden zone” of a widely accepted theory of star formation. “A widely accepted theory predicts that stars like this, with low mass and extremely low quantities of metals, shouldn’t exist because the clouds of material from which they formed could never have condensed,” said Elisabetta Caffau (Zentrum für Astronomie der Universität Heidelberg, Germany and Observatoire de Paris, France), lead author of the paper appearing in this week’s edition of Nature. The team found the star with the X-shooter and UVES instruments on the Very Large Telescope. Source: ESO
PLoS Biology : Publishing science, accelerating research A Peer-Reviewed, Open Access Journal Current Issue PLOS Biology is a peer-reviewed, open-access journal featuring research articles of exceptional significance in all areas of biological science, from molecules to ecosystems. The star that should not exist (PhysOrg.com) -- A team of European astronomers has used ESO’s Very Large Telescope (VLT) to track down a star in the Milky Way that many thought was impossible. They discovered that this star is composed almost entirely of hydrogen and helium, with only remarkably small amounts of other chemical elements in it. This intriguing composition places it in the "forbidden zone" of a widely accepted theory of star formation, meaning that it should never have come into existence in the first place. A faint star in the constellation of Leo (The Lion), called SDSS J102915+172927, has been found to have the lowest amount of elements heavier than helium (what astronomers call “metals”) of all stars yet studied. The team analysed the properties of the star using the X-shooter and UVES instruments on the VLT. “The star we have studied is extremely metal-poor, meaning it is very primitive. Also very surprising was the lack of lithium in SDSS J102915+172927.