Coming up: the mother of all celestial shows
Astronomers say the explosion of Eta Carinae would be a spectacular event and the fireworks would be "the best star show in the history of modern civilisation."tech reviews Updated: Jun 03, 2007 11:08 IST
Forget the 'brightest stellar explosion' of supernova SN 2006gy captured by the Chandra X-Ray Observatory last month. Here's the mother of all spatial explosions in the making - a hypernova called Eta Carinae.
Astronomers say it can explode anytime now. This celestial spectacle would be visible to the naked eye, says the Astrophysical Journal.
"It would be so bright that you could be able see it during the day, and even read a book by its light at night," says David Pooley of the University of California at Berkeley, who led the Chandra observations.
But there's more to it than it meets the eye.
The brightness of supernova SN 2006gy wasn't that obvious because the star that blew up was 240 million light years from the Earth in a galaxy called NGC 1260. But Eta Carinae is just 7,500 light years away from the Earth, has roughly the same size as the star behind SN 2006gy and is located in the Milky Way galaxy.
Although Eta Carinae was earlier expected to explode after about one million years or less, astronomers say as its current age is uncertain, it could explode anytime now because it's at roughly the same stage of its life as SN 2006gy.
Eta Carinae's mass - about 100 times greater than our Sun - makes it an excellent candidate for a full-blown hypernova. Historical records show that about 150 years ago, Eta Carinae underwent an unusual outburst and it produced almost as much visible light as a supernova explosion, but survived. It's now one of the brightest stars in the southern sky.
However, some astronomers fear that the stellar explosion in the Earth's celestial neighbourhood could touch off a mass extinction. In fact, some have proposed that just such a scenario could explain an extinction that took place 440 million years ago.
But this may well be a far-fetched conclusion, as the energetic jets emanating from Eta Carinae do not appear to be pointing towards Earth.
It is possible that the star, because of its proximity to the Earth, could have an impact on the planet but is highly unlikely to affect humans directly as they are protected from gamma rays by the atmosphere.
The fireworks would be "the best star show in the history of modern civilisation", Mario Livio of the Space Telescope Science Institute in Baltimore was quoted as saying by Newsweek magazine