Archive

Archive for March 2, 2013

Supermassive Black Hole Spins Super-Fast


Artist's conception. Image credit: NASA/JPL-Caltech

Artist’s conception. Image credit: NASA/JPL-Caltech

Imagine a sphere more than 2 million miles across – eight times the distance from Earth to the Moon – spinning so fast that its surface is traveling at nearly the speed of light. Such an object exists: the supermassive black hole at the center of the spiral galaxy NGC 1365.

Astronomers measured its jaw-dropping spin rate using new data from the Nuclear Spectroscopic Telescope Array, or NuSTAR, and the European Space Agency’s XMM-Newton X-ray satellites.

Astronomers measured its jaw-dropping spin rate using new data from the Nuclear Spectroscopic Telescope Array, or NuSTAR, and the European Space Agency’s XMM-Newton X-ray satellites.

Astronomers want to know the black hole’s spin for several reasons. The first is physical – only two numbers define a black hole: mass and spin. By learning those two numbers, you learn everything there is to know about the black hole.

Most importantly, the black hole’s spin gives clues to its past and by extension the evolution of its host galaxy. “The black hole’s spin is a memory, a record, of the past history of the galaxy as a whole,” explained Risaliti.

Full Story: http://www.cfa.harvard.edu/news/2013/pr201307.html
Also: http://www.jpl.nasa.gov/news/news.php?release=2013-075
Also: https://www.llnl.gov/news/newsreleases/2013/Feb/NR-13-02-08.html

The Birth Of A Giant Planet?


Astronomers using ESO’s Very Large Telescope have obtained what is likely the first direct observation of a forming planet still embedded in a thick disc of gas and dust. If confirmed, this discovery will greatly improve our understanding of how planets form and allow astronomers to test the current theories against an observable target.

An international team led by Sascha Quanz (ETH Zurich, Switzerland) has studied the disc of gas and dust that surrounds the young star HD 100546, a relatively nearby neighbour located 335 light-years from Earth. They were surprised to find what seems to be a planet in the process of being formed, still embedded in the disc of material around the young star. The candidate planet would be a gas giant similar to Jupiter.

“So far, planet formation has mostly been a topic tackled by computer simulations,” says Sascha Quanz. “If our discovery is indeed a forming planet, then for the first time scientists will be able to study the planet formation process and the interaction of a forming planet and its natal environment empirically at a very early stage.”

Full Story: http://www.eso.org/public/news/eso1310/

Stanford Scientist Closes In On A Mystery That Impedes Space Exploration


New research by Stanford aeronautics and astronautics Assistant Professor Sigrid Close suggests she’s on track to solve a mystery that has long bedeviled space exploration: Why do satellites fail?

In the popular imagination, satellites are imperiled by impacts from “space junk” – particles of man-made debris the size of a pea (or greater) that litter the Earth’s upper atmosphere – or by large meteoroids like the one that recently exploded spectacularly over Chelyabinsk, Russia.

Although such impacts are a serious concern, most satellites that have died in space haven’t been knocked out by them. Something else has killed them.

The likely culprit, it turns out, is material so tiny its nickname is “space dust.”

These natural micro-meteoroids are not directly causing satellites harm. When they hit an object in space, however, they are traveling so fast that they turn into a quasi-neutral gas of ions and electrons known as plasma. That plasma, Close theorizes, has the potential to create a radio signal that can damage, and even completely shut down, the satellites they hit.

Full Story: http://news.stanford.edu/pr/2013/pr-space-dust-threat-022613.html