A group of astronomers that were studying an enormous red giant star named BD+48 740 have made a startling discovery this week. Looking through the Hobby-Eberly Telescope in hopes of finding planets orbiting the aging star, what the international team discovered instead was the world’s first evidence of a planet being devoured by its own star. A nightmare scenario, the team got a glimpse of the possible fate of Earth some five billion years in the future when our sun turns into a red giant and swells into our orbital path. While, of course, the team didn’t directly witness the event they found two peculiar pieces of evidence that lead them to believe that the planetary event occurred.The first clue that the team found was the high amounts of lithium present in the makeup of BD+48 740. Surprising because of the ease in which it’s consumed inside of stars, the presence of high amounts of the rare element raised eyebrows because theorists have deduced that there are only a very few specific scenarios in which lithium can be present in stars. Usually present in stars that are much younger than BD+48 740, lithium was thought to have been created by the big bang and then consumed by the infant stars as a source of energy. To find this high of an amount of lithium in a star that is nearing the end of its life cycle is a good indication that the element was produced as a result of the destruction of a large planetary body as it dove into the fiery mass headfirst.The second and more peculiar indication that an object the size of a planet was destroyed is the second planet that the team discovered orbiting the red giant. While its existence isn’t unusual, its orbit is. Circling BD+48 740 in a strangely elliptical orbit is a planet 1.6 times the size of Jupiter. At the narrowest point of its travels around its sun, the huge planet is roughly the same distance as Mars is from our sun, however at the edge of its ellipse it’s much farther away than anything that researchers have ever seen. The fact of the odd distances aside, an elliptical orbit is something that is rare in the universe and is usually caused by an outside catalyst. The team is theorizing that this phenomenon was caused by the energy being released from its sister planet being destroyed which knocked it into such an odd orbit.While it’s a bit macabre, the discovery may shed some light on what our planet may experience in the distant future. Being some five billion years away, we of course will be long gone before that event happens, but perhaps the information gleaned can help future generations.Read more at the Penn State science page.
By adminPosted on