Dead star exploding.If the relaxing nature of stargazing star·gaze intr.v. star·gazed, star·gaz·ing, star·gaz·es 1. To gaze at the stars. 2. To daydream. Noun 1. makes you think that space is a peaceful place, think again. The galaxies are full of violent explosions that rip apart stars and hurl clouds of gas in all directions. Scientists recently got their closest look yet at a type of star explosion called a nova. Their observations gave them a new way to think about the most powerful type of star explosion, called a supernova supernova, a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. . The observations focused on a system called RS Ophiuchi RS Ophiuchi (RS Oph) is a nova approximately 5,000 light-years away in the constellation Ophiuchus. In its quiet phase it has an apparent magnitude of about 12.5. It erupted in 1898, 1933, 1958, 1967, 1985, and 2006 and reached about magnitude 5. , which is actually a pair of stars 5,000 light-years from Earth. One star is a white dwarf white dwarf, in astronomy, a type of star that is abnormally faint for its white-hot temperature (see mass-luminosity relation). Typically, a white dwarf star has the mass of the sun and the radius of the earth but does not emit enough light or other radiation to be , which on its own would have finished burning. It is small (about the size of Earth) and compact. Its companion star is a much bigger red giant that is nearing the end of its life and getting ready to explode. The red giant produces a strong wind that blows matter onto the white dwarf. When enough stuff builds up on the white dwarf, a powerful explosion takes place on the smaller star's surface. The result is a thermonuclear ther·mo·nu·cle·ar adj. 1. Of, relating to, or derived from the fusion of atomic nuclei at high temperatures: thermonuclear reactions. 2. blast. The last thermonuclear explosion in RS Ophiuchi occurred in 1985. This year on Feb. 12, Japanese astronomers Famous astronomers and astrophysicists include: Directory: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A
The explosion, scientists now report, created a shock wave that slammed into the red giant. The phenomenon looked a lot like what happens when a supernova spews matter from a dying star into space. Instead of happening over the usual thousands of years, however, this one happened over just a few months. Two weeks after the eruption, the radius of the blast was already greater than the distance between the sun and Saturn. The explosion started out in the shape of a ring. Then, over the next few months, it stretched out into a cigar shape. This suggests that the explosion came off the white dwarf in the form of jets, say scientists from Liverpool John Moores University Originally founded as a small mechanics institution (Liverpool Mechanics' School of Arts) in 1825, the institution grew over the centuries by converging and amalgamating with different colleges and eventually became the Liverpool Polytechnic. in Birkenhead, England. There are two ways to explain this unusual event, scientists say. Either the explosion shot off jets of matter in opposite directions or somehow the gas surrounding the red giant shaped the ejected material. Either way, this is a new phenomenon for astronomers to consider. And, once more matter builds up on the white dwarf, there may be another explosion in 20 years or so. |
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