Interstellar object 'Oumuamua believed to be 'active asteroid'

[Eugene]

Source: The Guardian

Interstellar object ‘Oumuamua believed to be ‘active asteroid’

Scientists believe cigar-shaped visitor to our solar system is fragment of a larger body

Nicola Davis
@NicolaKSDavis
Mon 13 Apr 2020 16.00 BST
Last modified on Mon 13 Apr 2020 20.20 BST

The cigar-shaped interstellar visitor to our solar system known as ‘Oumuamua could be the remnants of a larger body that was torn apart by its host star, according to researchers.

The dark, reddish object that hurtled into our solar system in 2017 and was named after the Hawaiian word for messenger or scout has long puzzled scientists.

Among its peculiarities is the lack of an envelope of gas and dust that comets typically give off as they heat up. Further work by experts suggested the body was accelerated by the loss of water vapour and other gases – as seen with comets but not asteroids. The upshot was that ‘Oumuamua was labelled a “comet in disguise”.

Now scientists say they have shed light on the mystery and addressed the myriad pieces of the ‘Oumuamua puzzle.

They say ‘Oumuamua is an “active asteroid” formed from a body that was torn apart by its parent star and then ejected into interstellar space.

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Read more: https://www.theguardian.com/science/2020/apr/13/interstellar-object-oumuamua-believed-to-be-active-asteroid

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Related: Tidal fragmentation as the origin of 1I/2017 U1 (‘Oumuamua) (Nature Astronomy)

[lastlib]

1. Have they checked its light curve?

Does it have one?

"First of all, there was the problem of Rama's light curve. It didn't have one.

All known asteroids, without exception, showed a slow variation in their brilliance, waxing and waning in a period of a few hours. It had been recognized for more than two centuries that this was an inevitable result of their spin and their irregular shape. As they toppled end over end along their orbits, the reflecting surfaces they presented to the sun were continually changing, and their brightness varied accordingly. Rama showed no such changes. Either it was not spinning at all, or it was perfectly symmetrical. Both explanations seemed unlikely."

--Rendezvous With Rama, Arthur C. Clarke

(asking for a friend.....)