Confirmed: Interstellar celestial body in the solar system for the third time
This is only the third time that a celestial body from outside the solar system has been discovered. Months remain for the observations of 3I/ATLAS.
The trajectory of 3I/ATLAS
(Image: NASA/JPL-Caltech)
Almost immediately after its discovery, it has now been confirmed that the third known interstellar celestial body is currently hurtling through the solar system. While the object was initially only known under the provisional designation A11pl3Z, it has now been christened 3I/ATLAS. This makes the celestial body only the third ever to be named according to the naming scheme introduced after the discovery of 1I/ʻOumuamua in 2017. 3I/ATLAS now has its page at the Minor Planet Center responsible for it, and NASA is also delighted with the discovery. The ATLAS telescope from Chile, with which this was achieved, is also funded by the US space agency and was now the inspiration for the naming ceremony.
No danger to Earth, plenty of time for observations
(Image:Â David Rankin, Saguaro Observatory)
NASA now summarizes once again that the interstellar celestial body was only discovered from Chile on Tuesday. Subsequently, however, the object was also discovered in older images, which now date back to June 14. Thanks to these “precoveries”, it was possible to determine its orbit and rule out any danger to Earth. It will approach our home planet to around 1.6 astronomical units (AU), i.e., it will always be further away than the sun. On October 30, it will approach the sun to 1.4 AU. Observatories on Earth will be able to observe it until September, after which it will be too close to the sun. From December, we will be able to find it again and follow its departure.
Videos by heise
Interstellar objects are celestial bodies that are not bound to a star and only pass through star systems like ours. Such a passage has only been reliably observed for two objects so far, 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019 and 2020. Both were of great interest to researchers because they came so close to us as objects from outside the solar system. 3I/ATLAS is now the hoped-for third specimen, and work is already underway to target the celestial body as quickly as possible with a wide variety of observatories.
The discovery of 3I/ATLAS now also recalls another episode in the history of the exploration of interstellar celestial bodies. It concerns a signal that the US astrophysicist Amir Siraj discovered in a NASA meteorite database. Together with his professor Avi Loeb, he went through a bureaucratic odyssey to confirm his assumption that it was the recording of an impact of an interstellar meteorite. Because some sensors belonged to the US military and were classified, it took years. Later, a research group declared that the signal could “almost certainly” be explained by a truck near the sensor.
(mho)
