Archive for November 8, 2012

Swinburne Team On Keck Discovers Farthest Supernova Ever

November 8, 2012 Leave a comment

Two ‘super-luminous’ supernovae — stellar explosions 10–100 times brighter than other supernova types — have been detected in the distant Universe, using the W.M. Keck Observatory on the top of Mauna Kea in Hawaii. The discovery, reported online in Nature this week, sets a record for the most distant supernova yet detected, and offers the rare possibility of observing the explosions of the first stars to form after the Big Bang.

“The type of supernovae we’ve found are extremely rare,” said Jeff Cooke, astrophysicist at Swinburne University of Technology, whose team made the discovery. “In fact, only one has been discovered prior to our work. This particular type of supernova results from the death of a very massive star (about 100 – 250 times the mass of our Sun) and explodes in a completely different way compared to other supernovae. Discovering and studying these events provides us with observational examples to better understand them and the chemicals they eject into the Universe when they die.”

Full Story:

An Unexpected Population Of Young-Looking Stars

November 8, 2012 Leave a comment

Hubble image of the globular star cluster NGC 6362. Credit: ESA/Hubble & NASA

The NASA/ESA Hubble Space Telescope offers an impressive view of the centre of globular cluster NGC 6362. The image of this spherical collection of stars takes a deeper look at the core of the globular cluster, which contains a high concentration of stars with different colours.

Tightly bound by gravity, globular clusters are composed of old stars, which, at around 10 billion years old, are much older than the Sun. These clusters are fairly common, with more than 150 currently known in our galaxy, the Milky Way, and more which have been spotted in other galaxies.

Recently, however, high precision measurements performed in numerous globular clusters, primarily with the Hubble Space Telescope, has led some to question this widely accepted theory. In particular, certain stars appear younger and bluer than their companions, and they have been dubbed blue stragglers. NGC 6362 contains many of these stars.

Full Story:

Canada-France-Hawaii Telescope Legacy Survey Reveals Dark Secrets Of The Universe

November 8, 2012 Leave a comment

At least a thousand distant galaxies can be identified on this image as little fuzzy dots. Credit: CFHT / Coelum

Astronomers from France and Canada have publicly released the final version of the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS), a unique and powerful multi-color collection of data obtained over 6 years from the summit of Mauna Kea. The imaging project probes an extremely large volume of the Universe, gathering tens of millions of galaxies, some as far as 9 billion light-years away, and provides a treasure trove for many years of astronomical research. This remarkable collection of data is a landmark achievement for CFHT and has inspired observatories around the world. The large number of published results from these images include dark matter maps on the largest scale ever observed and the first high-quality measurements which showed that dark energy closely resembles the cosmological constant that Albert Einstein predicted, but later thought might have been his greatest mistake.

The Legacy Survey observations began in 2003 and ended in 2009. Three more years were needed to accurately calibrate the huge volume of high-quality and homogeneous data obtained in five color-bands covering the optical domain from blue to red, including near-ultraviolet and near-infrared. The data revealed some 38 million objects, mostly very distant galaxies in various stages of evolution, across a combined area of sky totaling 155 square degrees (800 times the surface area of the full Moon as seen in the sky).

Full Story: