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Alien spaceship?

Started by Hardy Heinlin, Thu, 15 Nov 2018 05:07

Hardy Heinlin

Hello Universe.

'Oumuamua

I have two questions. I've read some discussions, but didn't find an answer.

The object was probably rotating (hence the variations of the light), and -- strangely -- when flying away from the sun it was accelerating.


Assuming it was accelerating due to comet outgassing.

What stopped the rotation in order to keep the outgassing in one stable direction?


Assuming it was accelerating due to a natural solar sail propulsion effect.

What stopped the rotation in order to keep the sail in a stable attitude?


Regards,

|-|ardy

Britjet

Differential outgassing? Or just the crew firing thrusters maybe...
Peter

Hardy Heinlin

Yes, and that could mean it wasn't a a natural object but an artificial object controlled by "something".


|-|ardy

Pierre Theillere

Hi Hardy and Peter,

Another possibility: rotation is slow enough to enable the "lit" side of the object to warm up enough, so that the ougassing always occurs from the side facing the sun... and maintains that acceleration away from the sun?
Pierre, LFPG

Hardy Heinlin


cagarini

#5
"On 27 June 2018, astronomers reported a non-gravitational acceleration to ʻOumuamua's trajectory, potentially consistent with a push from solar radiation pressure. Initial speculation as to the cause of this acceleration pointed to comet off-gassing, whereby portions of the object are ejected as the sun heats the surface. However, multiple objections have been raised to this possibility. Researchers point out that no such tail of gasses was ever observed following the object. Additionally, the anomalous acceleration was not observed when ʻOumuamua was passing at its closest to the sun as would be expected. A follow up analysis of these claims identifies that, were ʻOumuamua a comet, the off-gassing should have caused such an increase in rotational torque as to tear the object apart"

Strange, to say the least :-)

RogerH

Differential outgassing Peter? Didn't you do enough of that during WorldFlight?

Thing is, if this object came from outside our solar system, and possibly our galaxy, is it feasible that it doesn't conform to all of our understanding of physics?

Perhaps it is 'anti-gravatic', repelling rather than attracting...

Or maybe it's anti-photonic. repelled by light?

Just messing around really, but who can possibly say, if it originated outside our system?

We don't really know how gravity works, so perhaps there's another force working here which we've never come across before, but which nonetheless conforms to our version of physics, if we only knew all of it...

Back to the beer and chilli.

ScudRunner

Possibly executing a slingshot manoeuvre around the sun followed by some course correction activities ala the Apollo lunar missions....


Interesting to postulate!

Will

I thought it was kind of unfair for the team to speculate about a light sail while not addressing the tumbling motion. Either the whole contraption (object + sail) is tumbling, which would ruin the sail concept, or else the sail is fixed relative to the sun while somehow attached to a tumbling object. And that doesn't make sense.


Of course, tumbling is just inferred, right, because of the regular periodic dimming and brightening of the object. So maybe it isn't tumbling, but changing its brightness in some other way. Like anti-collision lights? ;-)
Will /Chicago /USA

torrence

Probably not  :)

Very inventive ideas here, but I spent a week last month at the annual Division for Planetary Science meeting and we had a great half day session on papers related to Omuamua observations and theory.  The light curve, shape and inferred strength are all consistent with a small 'rubble pile' of rocks and possibly some ices that was formed around a distant star and ejected by gravitational interactions with larger planets.  We've known for some time that we must encounter 'visitors' like this frequently but they are very difficult to detect and observe because they are coming in and leaving so fast, spending only days within range for most observations.  The real hero in this case is the Pan-STARRS telescope on Haleakala, Maui which was designed precisely to find distant small moving objects by covering huge areas of the sky over and over again and using sophisticated automated processing to look for faint things that move.  It's only been on line for a couple of years but has already made a lot of discoveries.  See:

https://panstarrs.stsci.edu/

The trajectory analysis is still on-going.  There are a lot of complicated dynamical effects such as degassing and radiation pressure that can change the orbit,  as well as more esoteric things like the Yarkovsky effect due to asymmetrical heat radiation which can move around small rocks in the asteroid belt and end up delivering them to earth as meteorites.  But unlikely to require alien solar-sails.  Maybe a Tardis, though ...

Cheers
Torrence
Cheers
Torrence

Zapp

I read "Rendezvous with Rama" 40 years ago, a piece of sci-fi poetry.

Who else thought about that?

Andrea

torrence

Rendezvous with Rama was a great book by Arthur C. Clarke. I grew up reading Clarke as one of my favorite SciFi authors due to his  realistic science and engineering background.  Actually met him once at a big Space Congress meeting some years ago.  Got a taste of his humor.  I told him I loved his work and it was one of the things that inspired me to go into a science career.  His response (with a grin) was "If half the people that told me that just donated 1% of their income to me, I wouldn't have to actually work writing books." 

Sequels with Gentry Lee had less stellar reviews but were still very interesting.  Gentry is a friend of mine at JPL and provided a lot of very realistic mission and engineering background to stories of later investigation of Rama.

Cheers
Torrence

 
Cheers
Torrence

Will

I discovered Arthur C. Clarke when I was about 10 or 11 years old... I have read every book and short story he's ever published. Delightful, imaginative storyteller, and a real optimist.
Will /Chicago /USA

Hardy Heinlin

I discovered Arthur C. Clarke through Stanley Kubrick :-)

cagarini

Quote from: Hardy Heinlin on Sat, 17 Nov 2018 22:11
I discovered Arthur C. Clarke through Stanley Kubrick :-)

Me too :-)  Actually seen 2001 about 8 times in my life, each one refining the observed details...

Once during a Sci Movie Week in the late 70s here in Portugal I saw in a row, 2001 and the original "Solaris", produced in times of the USSR... They were "light-year" away in terms of technique, but both touching very interesting concepts that have been following my interest in the Universe.

Martin Baker

Am I right in thinking the book was written to explain the movie?

Will

Clarke wrote a short story in 1948 called "The Sentinel." Kubrick was interested in it, and it became the spark that grew into 2001 A Space Odyssey. Kubrick hired Clarke to help with the screenplay.


While Clark was working on the screenplay for the film, he also wrote the novel. I don't think he would have said he wrote the novel specifically to explain the film, rather that it was his own take on the themes and ideas from the 2001 project, or an expanded take on the themes from The Sentinel.



Will /Chicago /USA

Martin Baker

Fascinating, thank you - i've downloaded the stories and will get reading.

For me, the best bit of the movie is the last 30 minutes or so, accompanied (at first) by that haunting Lux aeterna by Ligeti.

Phil Bunch

As a long-term fan of Arthur C. Clarke and the movie "2001", I also enjoyed the movie sequel "2010".  It is available through Amazon streaming movie service in the USA.  I'm not sure if people who are less enthusiastic 2001 and Clarke enthusiasts would enjoy 2010.

Wikipedia has the following info about 2001 sequels:

https://en.wikipedia.org/wiki/2001:_A_Space_Odyssey_(film)

"Clarke wrote three sequel novels: 2010: Odyssey Two (1982), 2061: Odyssey Three (1987), and 3001: The Final Odyssey (1997). The only filmed sequel, 2010: The Year We Make Contact, was based on Clarke's 1982 novel and released in 1984. Kubrick was not involved; it was directed by Peter Hyams in a more conventional style. The other two novels have not been adapted for the screen, although actor Tom Hanks in June 1999 expressed a passing interest in possible adaptations."

Best wishes,

Phil Bunch

cagarini

#19
Then, ( hey, don't get me wrong... I do believe they went to the Moon :-) )

there's that "conspiracy theory" about Kubrick having been the director of the "Apollo Plan B" :-)

Someone decided to put it into this:

https://www.youtube.com/watch?v=w5tWYmIOWGk

BTW: Here's an explanation, by Stanley Kubrick himself, on the "menaing " of the last scener in 2001...

https://www.youtube.com/watch?v=er_o82OMlNM