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Archive for September 20, 2011

Ashes from massacred planets hide black holes

September 20, 2011 Leave a comment

PLANETS and asteroids may be smashing into each other by the thousand around monster black holes. Dust from the collisions could explain why many of these colossal objects, which would otherwise shine brightly as they swallow nearby matter, are hidden from view.

Most galaxies like the Milky Way harbour a central black hole with a mass upwards of a million suns. While the Milky Way’s black hole is currently inactiveMovie Camera, many in other galaxies are swallowing up gas from dense discs that surround them, producing copious X-rays and other radiation in the process.

In addition to providing fodder for the black holes, these discs may give birth to millions of stars, explaining the dense star clustersMovie Camera seen in some galaxies’ hearts.

Full Story: http://www.newscientist.com/article/mg21128304.100-ashes-from-massacred-planets-hide-black-holes.html

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NASA’s WISE Mission Captures Black Hole’s Wildly Flaring Jet

September 20, 2011 Leave a comment

Image Credit: NASA

Image Credit: NASA

Astronomers using NASA’s Wide-field Infrared Survey Explorer (WISE) have captured rare data of a flaring black hole, revealing new details about these powerful objects and their blazing jets.

Scientists study jets to learn more about the extreme environments around black holes. Much has been learned about the material feeding black holes, called accretion disks, and the jets themselves, through studies using X-rays, gamma rays and radio waves. But key measurements of the brightest part of the jets, located at their bases, have been difficult despite decades of work. WISE is offering a new window into this missing link through its infrared observations.

“Imagine what it would be like if our sun were to undergo sudden, random bursts, becoming three times brighter in a matter of hours and then fading back again. That’s the kind of fury we observed in this jet,” said Poshak Gandhi, a scientist with the Japan Aerospace Exploration Agency (JAXA). He is the lead author of a new study on the results appearing in the Astrophysical Journal Letters. “With WISE’s infrared vision, we were able to zoom in on the inner regions near the base of the stellar-mass black hole’s jet for the first time and observe the physics of jets in action.”

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-298

Black Hole, Star Collisions May Illuminate Dark Matter

September 20, 2011 Leave a comment

Scientists looking to capture evidence of dark matter — the invisible substance thought to constitute much of the universe — may find a helpful tool in the recent work of researchers from Princeton University and New York University.

The team unveiled in a report in the journal Physical Review Letters this month a ready-made method for detecting the collision of stars with an elusive type of black hole that is on the short list of objects believed to make up dark matter. Such a discovery could serve as observable proof of dark matter and provide a much deeper understanding of the universe’s inner workings.

Postdoctoral researchers Shravan Hanasoge of Princeton’s Department of Geosciences and Michael Kesden of NYU’s Center for Cosmology and Particle Physics simulated the visible result of a primordial black hole passing through a star. Theoretical remnants of the Big Bang, primordial black holes possess the properties of dark matter and are one of various cosmic objects thought to be the source of the mysterious substance, but they have yet to be observed.

Full Story: http://www.princeton.edu/main/news/archive/S31/64/44M13/

Countdown to Europe’s first Soyuz launch under way

September 20, 2011 Leave a comment

Credits: ESA - S. Corvaja, 2011

Credits: ESA - S. Corvaja, 2011

The clock is ticking for the first Soyuz flight from Europe’s Spaceport in French Guiana. The rocket, which will carry the first two satellites of Europe’s Galileo navigation system into orbit, is being prepared for launch on 20 October.

Final assembly began on 12 September of the three-stage Soyuz ST-B, consisting of four first-stage boosters clustered around the core second stage, topped off by the third stage.

The Launcher Flight Readiness Review in July gave the green light to begin assembling the rocket.

The campaign began on 16 August in the assembly and testing building – known by its original ‘MIK’ Russian acronym – with electrical and mechanical tests of the upgraded, reignitable Fregat-MT upper stage. It will carry an additional 900 kg of propellants for its double-satellite load.

Full Story: http://www.esa.int/esaCP/SEMS693UNSG_index_0.html

Bus-sized satellite to re-enter Earth’s atmosphere this week

September 20, 2011 Leave a comment

UARS, a NASA satellite the size of a small bus, will re-enter Earth’s atmosphere later this week producing a brilliant fireball somewhere over our planet.  Best estimates place the re-entry time during the late hours of Sept. 23rd over a still-unknown region of Earth. Observers of the rapidly-decaying satellite say it is tumbling and flashing, sometimes almost as brightly as Venus.  Video images featured on today’s edition of http://spaceweather.com show how the doomed satellite looks through a backyard telescope.

Full Story: http://spaceweather.com/archive.php?view=1&day=20&month=09&year=2011

European tech could propel Nasa’s Orion capsule

September 20, 2011 Leave a comment

Europe is looking to play a significant role in America’s plans for the manned exploration of deep space.

Nasa has detailed its vision for a huge new rocket system that could send astronauts to asteroids and even Mars.

European engineers believe they could contribute to this project by providing the propulsion unit that pushes the rocket’s capsule to these locations.

Participation would require the agreement of European member states and a budget to fund the development work.

Full Story: http://www.bbc.co.uk/news/science-environment-14986217