Astronomers detect the aftermath of a collision between two ice giant exoplanets

Astronomers detect the aftermath of a collision between two ice giant exoplanets

According to a team of astronomers led by the Observatory from Leiden, the collision between two exoplanets with a mass of a few dozen Earths occurred at a distance of 2-16 AU (astronomical units) from the star. young sun-type star 2MASS J08152329-3859234.

2MASS J08152329-3859234 is a 300 million year old star located 567.2 parsecs (1,850 light years) away in the constellation Puppis. In December 2021, the star experienced a sudden optical dimming event and was assigned the designation ASASSN-21qj by the Automated All-Sky Survey for Supernovae (ASAS-SN). “Honestly, this observation was a complete surprise to me,” said Matthew Kenworthy, an astronomer at Leiden Observatory. “When we first shared this star’s visible light curve with other astronomers, we began observing it with a different series of telescopes.” “An astronomer pointed out on social media that this star brightened in the infrared for more than a thousand days before optically disappearing. I knew then that this was an unusual event.

Dr. Kenworthy and colleagues analyzed optical and infrared data collected by the Las Cumbres Observatory Global Telescope (LCOGT) and the Wide-field Infrared Survey Explorer (WISE) satellite. NASA in the years before and after the ASASSN-21qj fading event. They concluded that the most likely explanation is that two ice giant exoplanets collided, creating infrared light. Simon Lock, an astronomer at the University of Bristol, said: “Our calculations and computer models show that the temperature and size of the glowing material, as well as the duration of the glow, are consistent with the collision of two ice giant exoplanets”. . “The debris cloud expanded by the impact then moved in front of the star about three years later, causing the star’s brightness to decrease at visible wavelengths.”

The expanding debris cloud from the collision then moved in front of the star about three years later, causing the star’s brightness to decrease at visible wavelengths. “Over the next few years, the dust cloud will begin to disperse along the trajectory of the impact remnants, and the scattering of light from this cloud can be detected by both ground-based telescopes and NASA/ESA./CSA James Webb Space Telescope. “It will be interesting to observe the new developments,” said Zoe Leinhardt, an astronomer at the University of Bristol.

source: https://www.nature.com/articles/s41586-023-06573-9