Instead of investing in particle accelerators here on Earth, physicists might consider just blowing up a few stars. New images taken by the Chandra X-Ray Observatory show how supernova remnant Cassiopeia A acts as a natural particle accelerator, firing out cosmic rays. As particles move around the remnant, they’re accelerated by the tremendous magnetic fields, eventually nearing the speed of light. The images from Chandra show that the particles are being accelerated to the maximum rate predicted by theories.
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Super-Supermassive Black Hole
The Hubble Space Telescope, the Chandra X-Ray Observatory, and the National Radio Astronomical Observatory teamed up to produce this composite image of galaxy cluster MS0735.6+7421, located about 2.5 billion light-years from Earth. The cluster contains dozens of galaxies held together by gravity. A truly supermassive black hole lurks at the heart of this cluster, containing more than a billion solar masses. The red areas are twin jets of material streaming away from the black hole.
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Nearly a Thousand Years After the Death of a Star
In 1054 A.D., Chinese astronomers recorded the temporary brightening of a star in the constellation Taurus. Nearly 1000 years later, we look in the same region and see the exploded remnants of a dead star: the Crab Nebula. This composite photograph of the Crab Nebula was made by merging images from Hubble, the Chandra X-Ray Observatory, and the Spitzer Space Telescope. It shows only a hail of high-energy particles and expanding debris cloud that once was a massive star.
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Black Hole Stops Star Formation in Elliptical Galaxy
New images from NASA’s Chandra X-Ray Observatory show the environment around the supermassive black hole at the heart of M87, a nearby giant elliptical galaxy. Chandra detected loops and rings in the hot gas that surrounds the galaxy. These loops are evidence of periodic eruptions near the supermassive black hole, which send shockwaves through the surrounding gas. These outbursts happen every few million years, and prevent the gas in the cluster from cooling to create stars.
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Star Formation in NGC 3576
This photograph shows a star forming region in NGC 3576, located about 9,000 light years from Earth. The image was captured by NASA’s Chandra X-Ray Observatory, which reveals the higher energy emissions from the region. The blue dots are newly born stars generating ferocious solar winds (the more diffuse parts of the image). NGC 3576 is a particularly dense nebula, so many of these stars have been hidden from previous observations, until they were revealed by Chandra.
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The Location of the Oldest Recorded Supernova Discovered
Ancient Chinese astronomers recorded the occurence of a bright star in the sky in 185 AD; probably a supernova explosion. And now modern astronomers think they’ve found that explosion’s corpse: supernova remnant RCW 86. New calculations have found that RCW 86 is about 2000 years old, making it the best candidate for this ancient supernova. This new data was gathered using the XMM-Newton and Chandra X-Ray observatories.
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Galaxy Collision Separates Out the Dark Matter
There’s more dark matter than regular matter in the Universe, and they’re normally all mixed up together in galaxies. But astronomers using the Chandra X-Ray Observatory have found a situation where dark matter and normal matter can be wrenched apart. In a collision between giant galaxy clusters, hot gas clouds in the clusters encounter friction as they pass through one another, separating them from the stars. The dark matter isn’t affected by this friction either, so astronomers were able to calculate the effect of its gravity on regular matter.
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Chandra Confirms the Hubble Constant
Nearly every single astronomical measurement depends on the Hubble constant, a number that calculates the expansion of the Universe. NASA’s Chandra X-Ray Observatory recently measured this value independently, and came up with a similar number – 77 km per second per megaparsec (3.26 million light-years to the megaparsec). Give or take 15%. This confirms that the Universe is still between 12 and 14 billion years old.
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At the Centre of the Milky Way
You’re looking at the heart of your own galaxy with X-ray specs. This photograph was captured by NASA’s Chandra X-Ray observatory, and shows the three massive star clusters that surround the supermassive black hole at the centre of the Milky Way. These star clusters have so many large, bright stars that the whole area blazes in the X-ray spectrum. This photo shows 1 million seconds of accumulated observing time by Chandra of these mysterious region of our galaxy.
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Chandra Sees a Bridge Between Stars
Chandra X-Ray view of Mira AB; a red giant star probably orbiting a white dwarf. Image credit: Chandra. Click to enlarge.
For the first time an X-ray image of a pair of interacting stars has been made by NASA’s Chandra X-ray Observatory. The ability to distinguish between the interacting stars – one a highly evolved giant star and the other likely a white dwarf – allowed a team of scientists to observe an X-ray outburst from the giant star and find evidence that a bridge of hot matter is streaming between the two stars.
“Before this observation it was assumed that all the X-rays came from a hot disk surrounding a white dwarf, so the detection of an X-ray outburst from the giant star came as a surprise,” said Margarita Karovska of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., and lead author article in the latest Astrophysical Journal Letters describing this work. An ultraviolet image made by the Hubble Space Telescope was a key to identifying the location of the X-ray outburst with the giant star.
X-ray studies of this system, called Mira AB, may also provide better understanding of interactions between other binary systems consisting of a “normal” star and a collapsed star such as a white dwarf, black hole or a neutron star, where the stellar objects and gas flow cannot be distinguished in an image.
The separation of the X-rays from the giant star and the white dwarf was made possible by the superb angular resolution of Chandra, and the relative proximity of the star system at about 420 light years from Earth. The stars in Mira AB are about 6.5 billion miles apart, or almost twice the distance of Pluto from the Sun.
Mira A (Mira) was named “The Wonderful” star in the 17th century because its brightness was observed to wax and wane over a period of about 330 days. Because it is in the advanced, red giant phase of a star’s life, it has swollen to about 600 times that of the Sun and it is pulsating. Mira A is now approaching the stage where its nuclear fuel supply will be exhausted, and it will collapse to become a white dwarf.
The internal turmoil in Mira A could create magnetic disturbances in the upper atmosphere of the star and lead to the observed X-ray outbursts, as well as the rapid loss of material from the star in a blustery, strong, stellar wind. Some of the gas and dust escaping from Mira A is captured by its companion Mira B.
In stark contrast to Mira A, Mira B is thought to be a white dwarf star about the size of the Earth. Some of the material in the wind from Mira A is captured in an accretion disk around Mira B, where collisions between rapidly moving particles produce X-rays.
One of the more intriguing aspects of the observations of Mira AB at both X-ray and ultraviolet wavelengths is the evidence for a faint bridge of material joining the two stars. The existence of a bridge would indicate that, in addition to capturing material from the stellar wind, Mira B is also pulling material directly off Mira A into the accretion disk.
Chandra observed Mira with its Advanced CCD Imaging Spectrometer on December 6, 2003 for about 19 hours. NASA’s Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate, Washington. Northrop Grumman of Redondo Beach, Calif., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.
Additional information and images are available at:
http://chandra.harvard.edu and http://chandra.nasa.gov
Original Source: Chandra News Release