# wow, star showly explodes

Discussion in 'Astronomy, Exobiology, & Cosmology' started by blobrana, Mar 27, 2003.

1. ### blobranaRegistered Senior Member

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<b>Eruptive Star</b>

'V838 Monoceros'

March 27, 2003

<font size=2>T</font>he Hubble Space Telescope has spotted an eruptive star, <b>20,000</b> light-years away, that has brightened to 600,000 times its initial brilliance and suddenly became the brightest star in the Milky Way Galaxy. The star, named <b>V838 Monoceros</b>, swelled bigger than the orbit of Jupiter. While strangely remaining cool at its surface; unlike a nova or supernova (that is hot and eruptive, and tossing off outer layers in explosive out-bursts) The surface of V838 Mon is only about <b>2,000</b> degrees Celsius, less than half the temperature of our Sun, and one of the coolest stars know. The star is as bright as an ordinary nova, but it did not explosively eject its outer envelope. A hot core is exposed when a nova ejects its outer layers.

This event was observed from April to December 2002. The star's light bounces off the surrounding dust-shells that were cast-out by multiple eruptions 20,000 years ago. The dust shells have been expanding, since then, at <b>223,700</b> mph (100 kilometers per second) This echo is seen growing over 4 to 7 light-years, as the light illuminates new layers of material.

V838 Mon has now been observed with ground-based telescopes, and scientists now think the star may have shed a small part of its outer shell into space, which expanded and cooled. As a further complication it has been found that V838 Mon has a smaller, hotter companion star

"<i>This research will likely have significant impact on our understanding of the late phases of stellar evolution,</i>"
said Phil Ianna of the National Science Foundation.

But one thing for sure is that this rare short-lived event was a very lucky find...

Doh! pictures here...
http://www.geocities.com/douglasrana/v838.htm

Last edited: Mar 27, 2003