Posted on 03/13/2019 9:01:54 AM PDT by BenLurkin
Oumuamua appeared to hit the gas on its way out of the inner solar system. The body went a tiny bit faster than it should have if the only effect on its motion was the Suns gravity dragging on it. The best guess... was that ices vaporized from Oumuamuas surface by the Suns stark glare had given the body an extra kick. However, no observations had detected such outgassing.
...The team revisited all the observations made during Oumuamuas whiplash visit and have concluded that outgassing could indeed be to blame.
The researchers looked at what would happen if incident sunlight created a thruster-like jet of water vapor at the spot on Oumuamua that directly pointed at the Sun. As the body tumbled, this spot would change location, and so the jet created would migrate across the surface...
The tiny thrust from this migrating jet would cause the body to rock back and forth like a pendulum. This rocking would explain both the acceleration and the periodic pattern in Oumuamuas brightness, the researchers say....
But...[n]None of the authors plots of the objects changes in brightness reproduce the real light curve, particularly the pointy minima naturally created by a spinning elongated object. Just try spinning a cigar along its short axis, and youll see that the periods when you see it exposing [the] small cross-section pass quickly, he explains.
Furthermore, the outgassing should have changed Oumuamuas spin. Astronomers saw the bodys acceleration drop by a factor of four from late October to late November 2017 as the object raced away from the Sun. If this change happened because less sunlight was reaching the object and, thus, sublimating less ice, then the period of Oumuamuas pendulum-like tumbling should have doubled, which wasnt observed.
(Excerpt) Read more at skyandtelescope.com ...
Actually, there were 'many' sci-fi flicks with that plot.
Have they gone back and re-evaluated the movements of OTHER bodies having an equal surface area and mass for that time period ?
I can’t remember the name of any of them!.......................8^)
Don't all interstellar spaceships do that?
Once they've observed our planet's occupants, you betcha...
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