A French team of astronomers has discovered that two families of exocomets orbit the nearby star Beta Pictoris. The researchers used the HARPS instrument at ESO’s La Silla Observatory in Chile to make the most complete census of comets around another star ever created. "The expansive statistics of the comets that we observed with HARPS and the high quality of the instrument allowed us to distinguish two groups of detections," Flavien Kiefer of the Paris Institute of Astrophysics, lead author of the new study told astrowatch.net. "We found that these two groups were physically different and thus composed distinct families." The research was presented in a paper entitled "Two families of exocomets in the Beta Pictoris system" which is published in the journal Nature on Oct. 23.
Sunday, 26 October 2014
Sunday, 19 October 2014
Astronomers have used the APEX telescope to probe a huge galaxy cluster that is forming in the early Universe and revealed that much of the star formation taking place is not only hidden by dust, but also occurring in unexpected places. The Spiderweb Galaxy (formally known as MRC 1138-262) and its surroundings have been studied for twenty years, using ESO and other telescopes, and is thought to be one of the best examples of a protocluster in the process of assembly, more than ten billion years ago. This is the first time that a full census of the star formation in such an object has been possible. "To obtain a full census requires a lot of observing time at a broad range of telescopes using different techniques. As the observing time is very expensive and hard to obtain, this can only be done in a few very carefully selected regions, such as the proto-cluster surrounding the Spiderweb Galaxy," Carlos De Breuck, APEX project scientist at ESO, and a co-author of the new study told astrowatch.net.
Sunday, 12 October 2014
A new measurement of dark matter in the Milky Way has revealed there is half as much of the mysterious substance as previously thought. Australian astronomers used a method developed almost 100 years ago to discover that the weight of dark matter in our own galaxy is 800 billion times the mass of the Sun. They probed the edge of the Milky Way, looking closely, for the first time, at the fringes of the galaxy about 5 million trillion kilometres from Earth. Astrophysicist Dr Prajwal Kafle, from The University of Western Australia node of the International Centre for Radio Astronomy Research, said we have known for a while that most of the Universe is hidden. “Stars, dust, you and me, all the things that we see, only make up about 4 per cent of the entire Universe,” he said. “About 25 per cent is dark matter and the rest is dark energy.”
Sunday, 5 October 2014
Polish astronomers from the Optical Gravitational Lensing Experiment (OGLE) have discovered a young stellar bridge, that forms a continuous connection between the Magellanic Clouds. This finding is based on number density maps for stellar populations found in data gathered by OGLE. This is the most extensive optical survey of this region up to date. “We find that the young population is present mainly in the western half of the Magellanic Bridge area (MBR), which, together with the newly discovered young population in the eastern Bridge, form a continuous stream of stars connecting both galaxies along,” the researchers write in a paper published on Oct. 1. “The young population distribution is clumped, with one of the major densities close to the Small Magellanic Cloud (SMC), and the other, fairly isolated and located approximately midway between the Clouds, which we call the OGLE island.” The Magellanic Clouds comprise of two galaxies: the Large (LMC) and the Small Magellanic Cloud and are the closest to the Milky Way pair of interacting galaxies. The Clouds have always been of special interest to astronomers and they continue to play a significant role in our understanding of the Universe.