Scientists Discover Three Extrasolar Comets around Beta Pictoris

Researchers from the University of Innsbruck analyzed the data from the TESS mission of NASA and found some orbiting comets around Beta Pictoris, a nearby star outside our solar system.

Although the primary goal of TESS is to find exoplanets, it does have the potential to locate smaller objects and the latest observation of extrasolar comets around Beta Pictoris is a clear demonstration of its abilities. The technological sophistication of this special space telescope provides an opportunity to examine a precise light curve, which is extremely critical for finding smaller objects. A couple of students, Sebastian Zieba and Konstanze Zwintz, from the Institute for Astro and Particle Physics, analyzed the TESS light curve of Beta Pictoris to reveal this amazing information. They explained the discovery in the following words:

“The data showed a significant decrease in the intensity of the light of the observed star. These variations due to darkening by an object in the star’s orbit can clearly be related to a comet.”

Beta Pictoris

Beta Pictoris is about 23 million years old, which makes it quite young as far as stars are concerned. It has always been a celebrity in the astronomical world because of the information it carries. In the 1980s, the initial research of this star showed signs of planetary systems outside our solar system. It took scientists nearly 10 years after that to find an exoplanet for the first time. In addition to exoplanets, it also indicated (indirectly) the presence of comets in that research by making use of the gas evaporating from them.  

Discovery of Exocomets

Prior to this discovery, astronomers have recently found three similar exocomet systems by analyzing the data of the Kepler space telescope. All of these findings have been successful due to the interpretation of signals from these extrasolar comets. Scientists believe that the chances of finding exocomets are directly related to the age of the star (young stars are more likely to have these comets around them). Zwintz referred to this idea by mentioning that the Kepler mission was mainly focused on older stars and that’s the reason why we didn’t get these discoveries in the past. She expressed hope that we will continue to find more similar comets in the future because TESS explores the sky, completely (including young stars). Dr. Grant Kennedy, a member of the researching team from the University of Warwick, talked about the significance of this discovery and said,

“This discovery is really important for the science of extrasolar comets for several reasons. Beta Pictoris had been thought to host exocomets for three decades from a different technique, and the TESS data provide long overdue and independent evidence for their existence. Our next aim is to find similar signatures around other stars, and this discovery shows that TESS is up to the task.”

You can have a glance (animated) at these extrasolar comets in the following video:

Future Goals

The successful analysis of TESS’s data has urged the researchers to carry on with the good work and they now want to solve further mysteries about comets. For instance, they want to determine the composition and source of origin of the comets and figure out the scientific reason for their extraordinary tails. Zwintz commented on that by saying,

“In the future, we want to find answers to the question of how often exocomets occur and whether their number really decreases with the age of a star. Information about this is important because by analyzing the comets around a young star we can also draw conclusions about the history of our own solar system. Because we know that our solar system showed considerably more comets in ‘young years’. What we are seeing is not the comet nucleus itself, but the material blown off the comet and trailing behind it. So the TESS data do not tell us how big the comets were since the extent of the dust tail could be very big and not very dense, or less big and more dense. Both situations would give the same light curve.”

You can get all the information about Beta Pictoris here