Summary of the previous series:
In October 2017 in Hawaii, a strange astronomical object was discovered on the Pan-STARRS telescope.
It has a hyperbolic orbit, which is mainly why it is initially classified as a comet. And the orbit unequivocally indicates that this object flew in from outside the solar system. Arriving from the "north", the orbital inclination is about 120 degrees. That is, in the vicinity of the Sun was moving in the opposite direction to that in which the planets rotate.
After some time, the object's classification changes - it does not have the main feature of a comet (coma), that is, it does not “smoke”, nor does it have a tail. It is reclassified into asteroids.
It is open after passing through the perihelion, that is, it is already moving away from the Sun. Why after? It was too weak, dull, and then was close to the Sun (at a small angular distance from the Sun).
Determine the speed of the object at infinity, about 26 km / sec. So there is no doubt that the nature of the object is interstellar. He retrained in 1I / 2017 U1, I - interstellar, he is given the name - Oumuamua.
For variations in brightness, its rotation period is determined, approximately 8 hours. The brilliance is changing so much that we have to assume that it is something like a sausage (200x30x30 m), which in itself is strange (too elongated body, so far I have not had to face such). It is impossible to get an emission spectrum, it is clear that the body is dark, or rather dark red-brown.
Now retires towards the constellation Pegasus (flew from the constellation Lyra). Catch up (to try to study) is unrealistic. No such spacecraft.
So...
On June 27, 2018,
Hubble and the
European Southern Observatory press releases were issued, from which it follows that Oumuamua moves with a slight acceleration and its distance from the Sun is about 100,000 kilometers more than it should have been without acceleration. Therefore, it was proposed to classify Oumuamua again as a comet (the classic mechanism for non-gravitational acceleration of comets is the ejection of matter from the side illuminated by the Sun).
But the thing is that no emissions during the entire observation period of Oumuamua were found.
Read more about 1I / Oumuamua
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