Could Solar Radiation Explain 'Oumuamua's Strange Trajectory?

[.Scott]

This past June, research by Marco Micheli et al was published in Nature:
https://www.nature.com/articles/s41586-018-0254-4/

The gist of this article is that 'Oumuamua, (aka 1L/2017 U1) 2017's interstellar asteroid, was not following a strictly gravitational path around the sun. There is practical certainty (30 sigma) that it was being pushed away from the sun during its transit. The out-gassing of comets causes them to be similarly pushed away from the sun, but there was no other indication that 'Oumuamua might be out-gassing. More specifically, out-gassing should have resulted in a change in 'Oumuamua's angular velocity and no such change occurred.

There is now a recent article by Shmuel Bialy and Abraham Loeb
https://arxiv.org/abs/1810.11490
They demonstrate that if 'Oumuamua is very thin, solar radiation could explain the observed trajectory - and that such an asteroid could have survived a trek to our Solar System.

 

[davenn]

There is now a recent article by Shmuel Bialy and Abraham Loeb
https://arxiv.org/abs/1810.11490
They demonstrate that if 'Oumuamua is very thin, solar radiation could explain the observed trajectory - and that such an asteroid could have survived a trek to our Solar System.

thanks, Scott

An interesting possibility Dave

 

[OmCheeto]

Bwah! What!

Cigar-shaped interstellar object may have been an alien probe, Harvard paper claims [CNN]
Updated 10:47 AM ET, Tue November 6, 2018​

Wondering who on Earth would publish this, I found that they reference your referenced paper!:

There is now a recent article by Shmuel Bialy and Abraham Loeb
https://arxiv.org/abs/1810.11490

Alternatively, a more exotic scenario is that ‘Oumuamua may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization.
...
A survey for lightsails as technosiganures in the Solar System is warranted, irrespective of whether ‘Oumuamua is one of them.
​

Anyways, even if it's only a one in a bazillion chance, it's fun to think about.

 

[Lord Crc]

Given how long it took to figure out the Pioneer anomaly, an object we knew all the details about, I'd wait a bit longer to proclaim "it's aliens!"...

 

[DaveC426913]

They demonstrate that if 'Oumuamua is very thin, solar radiation could explain the observed trajectory - and that such an asteroid could have survived a trek to our Solar System.

What do they mean by 'thin'? They talk about surface area to mass - does that mean they mean "thin-walled" - as in hollow?

 

[DrStupid]

What do they mean by 'thin'?

They seem to think about a paperborad with the same area density of ${\textstyle{m \over A}} \approx 0.1{\textstyle{g \over {cm^2 }}}$. Of course this value doesn't necessarely mean that the thickness is in the range of millimeters. But even for a structure made of aerogel it would be not more than a meter.

 

[TEFLing]

https://www.forbes.com/sites/starts...llar-space-what-we-know-today-about-oumuamua/