Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: chiralSPO on 13/12/2017 18:03:19

Title: What is Oumuamua (our extrasolar visitor)?
Post by: chiralSPO on 13/12/2017 18:03:19

So apparently there is an object a few hundred meters long and about 100m across from well beyond the solar system that is traveling about between 20 and 45 km/s on a trajectory that brought it fairly close to all four terrestrial planets (it was about 32M km from earth at the closest). In the next day or two we will know whether or not there are any signs of AC currents or changing electromagnetic fields, because we have just trained a powerful radio telescope on the object, and will be able to detect any signal as strong as a cell phone.

Given what we know, it's almost certainly a radiation-seared rock that has been tumbling through interstellar space for millions or billions of years, but it is the first of its kind to be observed, and we would be remise if we had passed up the opportunity to see if it were actually an alien vessel or something, because how awesome would that be!

https://solarsystem.nasa.gov/planets/oumuamua/indepth

http://www.sciencemag.org/news/2017/11/updated-first-time-astronomers-are-tracking-distant-visitor-streaking-through-our-solar

https://www.space.com/39046-interstellar-object-oumuamua-breakthrough-listen-project.html

Title: Re: What is Oumuamua (our extrasolar visitor)?
Post by: Bill S on 13/12/2017 20:35:01

As you suggest, ChiralSPO, more likely to be a lump of rock than an alien craft.

Quote

These properties suggest that 'Oumuamua is dense, composed of rock and possibly metals, has no water or ice, and that its surface was reddened due to the effects of irradiation from cosmic rays over hundreds of millions of years

Interesting links.

Title: Re: What is Oumuamua (our extrasolar visitor)?
Post by: evan_au on 13/12/2017 20:49:50

Being the first object confirmed as extrasolar (due to its hyperbolic path through the Solar System), it caused a dilemma for the body which names astronomical objects.
They created a new category for it!

https://en.wikipedia.org/wiki/%CA%BBOumuamua

Title: Re: What is Oumuamua (our extrasolar visitor)?
Post by: chris on 15/12/2017 22:50:32

(https://i.guim.co.uk/img/media/593bee367cce37dde4a7b616c7b08349d485247b/205_123_903_542/master/903.jpg?w=1920&q=55&auto=format&usm=12&fit=max&s=88867014d14b3dd0f3b73f2104012b09)

[An artist’s impression of the ‘Oumuamua asteroid, which scientists are scanning for signs of intelligent life. Illustration: ESO/M Kornmesser/PA]

I am amazed that - hopefully like this space rock - this story totally passed me by... somehow...

I missed it completely, although I am now totally intrigued and caught up in the mystery.

Is it genuinely entering the solar system though, or could it have been on some incredibly long deep orbit having been ejected  onto such a trajectory by a collision or other cosmic catastrophe in the past?

Title: Re: What is Oumuamua (our extrasolar visitor)?
Post by: teragram on 15/12/2017 23:17:34

Arthur C Clarke wrote the story, published in 1973, "Rendezvous with Rama". A spaceship was dispatched from Earth with a crew whose task was to land on the object in order to carry out examinations.
It seems that this time, 44 years later, we can't respond as quickly as then! (just a light-hearted comment). I won't reveal any of the plot, don't want to spoil it for those who haven't read it.

Title: Re: What is Oumuamua (our extrasolar visitor)?
Post by: RD on 15/12/2017 23:43:40

Quote from: chris on 15/12/2017 22:50:32

(https://i.guim.co.uk/img/media/593bee367cce37dde4a7b616c7b08349d485247b/205_123_903_542/master/903.jpg?w=1920&q=55&auto=format&usm=12&fit=max&s=88867014d14b3dd0f3b73f2104012b09)

[An artist’s impression of the ‘Oumuamua asteroid, which scientists are scanning for signs of intelligent life. Illustration: ESO/M Kornmesser/PA]

It could actually be more like a dumb-bell / dog-bone  ...

Quote from: scientificamerican

the truth is that current astronomical data really only gives a range of dimensions, and this object [Oumuamua] could have a more ordinary 4:1 axial ratio.

https://blogs.scientificamerican.com/life-unbounded/the-strange-lumpy-world-of-asteroids/