Astronomers Discover Giant Star "Digesting" Its Own Planet

Astronomers at Penn State University have discovered a star with a radius 11 times larger than our sun swallowing one if its own planets.

The star is a red giant, which signifies that it is in the later stages of its life.  Red giants usually have an inflated atmosphere and a mass somewhere between mass 0.5 and 10 solar masses.

The red giant in question, named BD+48740, is older than our sun and its hunger serves as an omen of Earth's likely fate.

Penn State Astronomer Alex Wolszczan states that "A similar fate may await the inner planets in our solar system, when the sun becomes a red giant and expands all the way out to Earth's orbit some 5 billion years from now."

What signified the star's consumption of its own planet was a high reading of the rare element lithium in the red giant.

Wolszczan revealed that "in the case of BD+48740, it is probable that the lithium production was triggered by a mass the size of a planet that spiraled into the star and heated it up while the star was digesting it."

Another curious aspect of the study was the abnormally elliptical orbit of a planet around that star that is 1.6 times the size of Jupiter.

Fellow author of the study, Andrzej Njedzielski explains, "We discovered that this planet revolves around the star in an orbit that is only slightly wider than that of Mars at its narrowest point, but is much more extended at its farthest point...Such orbits are uncommon in planetary systems around evolved stars and, in fact, the BD+48740 planet's orbit is the most elliptical one detected so far."

Contributor to the study, Eva Villaver, states that "the highly elongated orbit of the massive planet we discovered around this lithium polluted red-giant star is exactly the kind of evidence that would point to the star's recent destruction and its now-missing planet."

Scientists used the Hobby-Eberly Telescope at the McDonald Observatory in Texas to conduct their research.