Stories tagged chandra

Spiral galaxy M81: The black hole in the center of this galaxy is 70 million times as massive as the Sun, but it behaves exactly the same as much, much smaller black holes.
Courtesy X-ray: NASA/CXC/Wisconsin/D.Pooley & CfA/A.Zezas; Optical: NASA/ESA/CfA/A.Zezas; UV: NASA/JPL-Caltech/CfA/J.Huchra et al.; IR: NASA/JPL-Caltech/CfA

This may fall under the heading of small comfort, but a new study has shown that all black holes, big or small, suck in matter in the same way. Using NASA’s Chandra X-ray observatory, astronomers studied the different types of light (X-ray, radio and visible) emanating from the region around a massive black hole in the center of galaxy M81. They found that this light was the same as light coming from smaller black holes, even though this one is some 10 million times bigger, and is sucking in matter from a different source. This confirms a part of Einstein’s theory of relativity, which predicted that black holes would be fairly simple objects, not subject to a lot of variation. Which doesn’t really help much if you find yourself getting sucked in, but at least you know it’s nothing personal.

You can learn more about Chandra and X-ray astronomy in our Be an Astronomer! web exhibit. And you can ask questions of Megan Donahue, a scientist who work with the Chandra observatory.

Tags : X-rays, light, galaxy, chandra, black holes, astronomy

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Artist's Visualization of a Black Hole: Artists Visualization of a Black Hole
Courtesy XMM-Newton, ESA, NASA

A recent study shows black holes to be some of the most energy efficient engines in the universe, as well as playing a role in preventing galaxies from growing too large.

Black holes are super-dense objects formed when massive stars deplete their internal nuclear fuel and collapse into themselves. A black hole's gravitational force is so strong anything that wanders too close - such as a companion star or cosmic debris - eventually gets sucked into it. Super-massive black holes are thought to make up the centers of galaxies.

Using NASA's orbiting Chandra X-ray Observatory, scientists studied nine older black holes located in star systems 55 million to 442 million light years from Earth. A light-year is the distance light travels in a year, approximately 6 trillion miles. The study measured both the amount of hot gas being drawn into the black holes and the high-energy particles being ejected from them.

Surprisingly, these "galactic engines" proved to be 25 times more efficient than anything man-made, even nuclear power.

"If you could make a car engine that was as efficient as one of these black hole engines you could get about a billion miles per gallon of gas", said study lead author Steve Allen of Stanford University and the Stanford Linear Accelerator Center.

Scientists think the conversion processes could be connected to the black holes' spin rates and magnetic fields.

The high energy spewed from these celestial engines at near the speed of light also seems to regulate galaxy size. Areas of heat produced from the jets prevent gas from cooling and forming new stars.

"The black holes are actually preventing galactic sprawl from taking over the neighborhood", said astrophysicist Kim Weaver of NASA.

Tags : space, black holes. engines, energy, chandra

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