NASA has revealed the existence of 3I/ATLAS, the third interstellar object observed in the universe. This object is not gravitationally bound to any star and exists in interstellar space, the area between stars.
The discovery was made by NASA’s Asteroid Terrestrial Impact Alert System (ATLAS), a network of four telescopes that scan the entire sky several times each night to detect potential asteroid threats. The object was initially identified as a possible collision path with Earth, but NASA assures there is no risk of it hitting our planet.
3I/ATLAS is estimated to be 20 kilometers in size and is currently located about 670 million kilometers from the sun. It is approaching our star at a speed of 61 km per second and will head straight through the solar system into interstellar space, never to be seen again.
The object’s name comes from the ATLAS research team that discovered it. The “I” stands for “interstellar,” indicating its origin outside the solar system. Astronomers believe studying 3I/ATLAS could provide valuable insights into objects in distant reaches of space.
Ground-based telescopes will be able to observe 3I/ATLAS until September, after which it will enter Mars’ inner orbit and disappear from view. However, it will reappear from the sun’s shadow in early December, becoming visible again. As an active comet, 3I/ATLAS may form a nebula-like cloud of gas and dust as it heats up near the sun.
Source: https://www.wired.com/story/heres-what-we-know-about-the-third-interstellar-object-in-history