NASA’s Exoplanet-Hunting Satellite Captures Explosive Outburst Of Passing Comet

For the first time, a team of astronomers was able to conduct a detailed and complete observation of an explosive emission by a comet. They were able to study the natural phenomenon using NASA’s Transiting Exoplanet Survey Satellite (TESS).

The comet that became the subject of the astronomers’ study has been identified as 46P/Wirtanen, According to the researchers, this comet reached its closest distance to Earth on Dec. 16, 2018. But, before carrying out its near-Earth visit, the comet produced a massive outburst of gas, dust and ice.

Fortunately, TESS was able to capture the outburst as the comet passed in front of the satellite.

“TESS spends nearly a month at a time imaging one portion of the sky. With no day or night breaks and no atmospheric interference, we have a very uniform, long-duration set of observations,” astronomer Tony Farnham from the University of Maryland said in a press release.

“As comets orbit the Sun, they can pass through TESS’ field of view,” he added. “Wirtanen was a high priority for us because of its close approach in late 2018, so we decided to use its appearance in the TESS images as a test case to see what we could get out of it. We did so and were very surprised!”

Comets are believed to produce outbursts as they get heated by the light from the Sun. This rapidly vaporizes the ice particles on the comet’s surface, causing an outburst that can disrupt the other materials of the space rock.

In the case of 46P/Wirtanen, the outburst began with a bright flash that lasted for about an hour. Then, the flash became brighter over the span of eight hours. The astronomers believe the gradual brightness was caused by the cloud of dust that erupted from the comet’s surface. These dust particles may have reflected the sunlight, causing the flash to grow brighter.

The natural event lasted for over two weeks, which allowed the astronomers to carry out extensive observations on 46P/Wirtanen’s outburst.

With 20 days’ worth of very frequent images, we were able to assess changes in brightness very easily. That’s what TESS was designed for, to perform its primary job as an exoplanet surveyor,” Farnham said.

The study carried out by the researchers on 46P/Wirtanen was published in the Astrophysical Journal Letters.