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Posts Tagged ‘max planck institute’

When Dark Energy Turned On


The Sloan Digital Sky Survey (SDSS-III) today announced the most accurate measurements yet of the distances to galaxies in the faraway universe, giving an unprecedented look at the time when the universe first began to expand at an ever-increasing rate. Scientists from the University of Portsmouth and the Max-Planck Institute for Extraterrestrial Physics will present the new results in a press conference at 1000 BST on Friday 30 March at the National Astronomy Meeting in Manchester.

The results are available in six related papers posted to the arXiv preprint server and are the culmination of more than two years of work by the team of scientists and engineers behind the Baryon Oscillation Spectroscopic Survey (BOSS), one of the SDSS-III’s four component surveys.

“There’s been a lot of talk about using galaxy maps to find out what’s causing accelerating expansion,” says David Schlegel of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, the principal investigator of BOSS. “We’ve been making a map, and now we’re using it – starting to push our knowledge out to the distances when dark energy turned on.”

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012/pressreleases/nam23.html

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Interstellar Beacons Could Help Future Astronauts Find Their Way


The use of stars, planets and stellar constellations for navigation was of fundamental importance for mankind for thousands of years. Now a group of scientists at the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany have developed a new technique using a special population of stars to navigate not on Earth, but in voyages across the universe. Team member Prof. Werner Becker will present their work at the National Astronomy Meeting in Manchester on Friday 30 March.

Full Story: http://www.jodrellbank.manchester.ac.uk/meetings/nam2012/pressreleases/nam15.html

Recycling Galaxies Caught in the Act

March 14, 2012 Leave a comment

When astronomers add up all the gas and dust contained in ordinary galaxies (like our own Milky Way), they find a discrepancy: there is not nearly enough matter for stars to form at the observed rates for long. As a (partial) solution, a matter cycle on gigantic scales has been proposed. In our local galactic neighbourhood, traces of this mechanism had already been found. Now, a study led by Kate Rubin of the Max Planck Institute for Astronomy has found the first direct evidence of such gas flowing back into distant galaxies that are actively forming new stars, validating a key part of “galactic recycling”.

Full Story: http://www.mpia.de/Public/menu_q2.php?Aktuelles/PR/2012/PR120314/PR_120314_en.html

Globular Star Clusters Survived 13-Gyr-Old Massacre

February 14, 2012 Leave a comment

Our Milky Way galaxy is surrounded by some 200 compact groups of stars, containing up to a million stars each. These globular clusters are almost as old as the universe itself and hold valuable information on how the first generations of stars and galaxies formed. Now a team of astronomers from Germany and the Netherlands have conducted a novel type of computer simulation that looked at how they were born – and they find that these giant clusters of stars are the only survivors of a 13 billion year-old massacre that destroyed many of their smaller siblings. The new work, led by Dr Diederik Kruijssen of the Max Planck Institute for Astrophysics in Garching appears in a paper in the journal Monthly Notices of the Royal Astronomical Society.

Globular star clusters have a remarkable characteristic: the typical number of stars they contain appears to be about the same throughout the Universe. This is in contrast to much younger stellar clusters, which can contain almost any number of stars, from fewer than 100 to many thousands. The team of scientists proposes that this difference can be explained by the conditions under which globular clusters formed early on in the evolution of their host galaxies.

The researchers ran simulations of isolated and colliding galaxies, in which they included a model for the formation and destruction of stellar clusters. When galaxies collide, they often generate spectacular bursts of star formation (“starbursts”) and a wealth of bright, young stellar clusters of many different sizes. As a result it was always thought that the total number of star clusters increases during starbursts. But the Dutch-German team found the opposite result in their simulations.

Full Story: http://www.mpa-garching.mpg.de/mpa/institute/news_archives/news1202_aaa/news1202_aaa-en.html

Subaru Telescope Captures Images of the “Stealth Merger” of Dwarf Galaxies

February 8, 2012 Leave a comment

An international team of scientists led by David Martinez-Delgado (Max Planck Institute for Astronomy, Germany) has conducted research that reveals a “stealth merger” of dwarf galaxies, where an in-falling satellite galaxy is nearly undetectable by conventional means yet has a substantial influence on its host galaxy. Aaron Romanowsky (University of California Observatories in Santa Cruz) along with graduate student Jacob Arnold (UCSC) used the Subaru Telescope to obtain high-resolution images of individual stars in a dense stream of stars in the outer regions of a nearby dwarf galaxy (NGC 4449); these outlying stars are the remains of an even smaller companion galaxy in the process of merging with its host (Figure 1). NGC 4449, the host galaxy, is the smallest primary galaxy in which a stellar stream from an ongoing merger has been identified and studied in detail. Romanowsky commented, “I don’t think I’d ever seen a picture of a galaxy merger where you can see the individual stars. It’s really an impressive image.”

Full Story: http://subarutelescope.org/Pressrelease/2012/02/08/index.html

A Boost for European Radio Astronomy

January 5, 2012 Leave a comment

Credit: ESO/ALMA (www.alma-telescope.org); SPDO/TDP/DRAO/Swinburne Astronomy Productions.

Credit: ESO/ALMA (www.alma-telescope.org); SPDO/TDP/DRAO/Swinburne Astronomy Productions.

The European astronomy collaboration RadioNet has been granted 9.5 million Euros by the European Commission to fund its latest program,RadioNet3, for the years 2012 to 2015. RadioNet is responsible for improving the capabilities of, and enhancing access to, major radio astronomy facilities in Europe and beyond. This third iteration not only continues the two preceding RadioNet projects, but also takes a leap forward in stimulating new activities in research and development for the existing radio infrastructures, in synergy with telescopes of the future. These include the recently opened Atacama Large Millimetre/submillimetre Array (ALMA) and – upcoming in the next decade – the biggest radio telescope in the world – the Square Kilometre Array (SKA).

The Max Planck Institute for Radio Astronomy (MPIfR) in Bonn is leading the RadioNet3 consortium of 27 partners. It includes all major European radio institutions, as well as partners South Korea, Australia and South Africa.

 

A Black Hole’s Dinner is Fast Approaching

December 14, 2011 Leave a comment

Astronomers using ESO’s Very Large Telescope have discovered a gas cloud with several times the mass of the Earth accelerating fast towards the black hole at the centre of the Milky Way. This is the first time ever that the approach of such a doomed cloud to a supermassive black hole has been observed. The results will be published in the 5 January 2012 issue of the journal Nature.

During a 20-year programme using ESO telescopes to monitor the movement of stars around the supermassive black hole at the centre of our galaxy (eso0846), a team of astronomers led by Reinhard Genzel at the Max-Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany, has discovered a unique new object fast approaching the black hole.

Over the last seven years, the speed of this object has nearly doubled, reaching more than 8 million km/h. It is on a very elongated orbit  and in mid-2013 it will pass at a distance of only about 40 billion kilometres from the event horizon of the black hole, a distance of about 36 light-hours. This is an extremely close encounter with a supermassive black hole in astronomical terms.

This object is much cooler than the surrounding stars (only about 280 degrees Celsius), and is composed mostly of hydrogen and helium. It is a dusty, ionised gas cloud with a mass roughly three times that of the Earth. The cloud is glowing under the strong ultraviolet radiation from the hot stars around it in the crowded heart of the Milky Way.

Full Story: http://www.eso.org/public/news/eso1151/