In the fall, an international group of scientists successfully recorded the results of a collision between two icy exoplanets orbiting the Sun-like star ASASSN-21qj. A dust cloud formed from the celestial debris and eventually moved to a point between the star and Earth. It was recently revealed that amateur astronomers helped experts with this discovery. Experts were the first to notice the star’s strange behavior. It first became twice as bright in the infrared region, then gradually began to fade.
The story begins in 2021, when the ASAS-SN telescope network discovered for the first time that a Sun-like star 1,800 light-years from Earth was rapidly transitioning into visible light. About 30 days later, amateur astronomer Artu Sainio saw a conversation between two professional astronomers, Dr. Artu Sainio, on social networks. Matthew Kenworthy and Dr. Eric Mamajek, who speculated on the reason for this strange occurrence. Intrigued, Sainio decided to take a closer look at the data on the star, called ASASSN-21qj,
After reviewing archived data from NASA’s NEOWISE program, an amateur astronomer discovered that the star showed a sudden increase in brightness in infrared light two years before it was expected to disappear in visible light. So he joined the discussion on social networks and shared his discovery with two experts. “Amateur astronomer Arttu Sainio noted on social networks that the star lit up in the infrared more than a thousand days before the optical dimming. Then I realized that this was an unusual event,” Kenworthy said.
Sainio is now one of the co-authors of a new paper published in Nature. In scientific papers, professional and amateur astronomers present evidence that the brightness increase and dimming of the star ASASSN-21qj is due to the collision of two icy giant planets weighing tens of Earths. I was able to collect. According to their calculations, the exoplanet struck the star at a distance of between 2 and 16 AU. This event produced an infrared glow, and three years later, the cloud of debris that formed at the explosion site grew and moved to a point between ASASSN-21qj and Earth, increasing the star’s brightness in the visible wavelength range. It got dark. Additional observations helped determine the star’s properties. Amateur spectroscopist Hamish Barker attempted to capture the spectrum of ASASSN-21qj in late July 2022 to determine its temperature. But the star was so faint that Barker asked French amateur astronomer Olivier Gardet to add ASASSN-21q to his list of targets. The team, called the Southern Spectroscopy Project Observatory Team, was able to collect the necessary spectra and send them to Kenworthy in early September 2022.
In addition, two other amateur astronomers observed the star and contributed to the research. Amateur spectroscopist Sean Currie provided the spectrum of ASASSN-21qj in early April 2023, and Franz Josef Hambusch monitored the star from the ROAD observatory in the Atacama Desert and sent the results through the AAVSO database. reported. In the coming years, the dust cloud that formed at the collision site of the two exoplanets will begin to dissipate in orbit. Scientists hope this will allow them to study the explosion’s aftermath using ground-based telescopes or the James Webb Space Telescope. During that time, they were able to observe thermal afterglow.
source: https://science.nasa.gov/get-involved/citizen-science/amateur-astronomers-help-discover-cosmic-crash/
https://www.nature.com/articles/s41586-023-06573-9