Interstellar Interlopers, Coming in from the great beyond |
Interstellar Interlopers, Coming in from the great beyond |
Oct 27 2017, 01:40 PM
Post
#31
|
|
Member Group: Members Posts: 541 Joined: 17-November 05 From: Oklahoma Member No.: 557 |
They finally found a chunk of something coming into the Solar System. Something much bigger than cosmic rays or dust particles.
Asteroid/comet in hyperbolic trajectory |
|
|
Dec 19 2017, 09:56 AM
Post
#32
|
|
Senior Member Group: Members Posts: 2346 Joined: 7-December 12 Member No.: 6780 |
This seems to be within the possible scenarios on the basis of the noisy data.
But lack of evidence regarding the interior appears to be a pretty thin basis to conclude "moist" in the interior. I'd be pretty sure, that we'll also see different interpretations in the future. |
|
|
Dec 20 2017, 04:25 AM
Post
#33
|
|
Senior Member Group: Members Posts: 2530 Joined: 20-April 05 Member No.: 321 |
It seems like the number of possible hypotheses is hard to bound, but one that comes to mind would be that it is a body that was once part of another planetary system that was ejected via gravity assists and has taken a long time to cross interstellar distances.
A gravity assist adds a velocity less than the orbital velocity of the assisting (large) planet to the assisted (small) object. For this object to get such a large velocity before arriving at our system would require some very exceptional circumstances – compared to anything in our system. It seems that the velocity of the assisting object must have been very high. So one scenario would be a double star system or a system with a hot Jupiter that accelerated a small object that got in the right place at the right time. This would necessarily imply a passage close to at least one star, although that passage could have been arbitrarily brief and the star need not necessarily be as hot as Sol. By no means does this discussion exhaust the possibilities, but it seems to be copacetic with our knowledge of planetary systems around dwarf stars. I don't know how one could quantify the possibility that it might come from a system very atypical of ones we currently know of. |
|
|
Dec 20 2017, 05:19 PM
Post
#34
|
|
Member Group: Members Posts: 684 Joined: 24-July 15 Member No.: 7619 |
It seems like the number of possible hypotheses is hard to bound, but one that comes to mind would be that it is a body that was once part of another planetary system that was ejected via gravity assists and has taken a long time to cross interstellar distances. If this started as a binary KBO on a comet-like path, could our sun eject it? We know the outbound path, but until there are precovery images, we're extrapolating the inbound path, correct? Given that lots of solar KBOs are binary, (mostly the cold population, but some hot as well) and binary encouters can result in one "captured" the other "ejected", could a close binary KBO result in one body being accellerated out of our solar system? |
|
|
Dec 20 2017, 10:08 PM
Post
#35
|
|
Senior Member Group: Members Posts: 2530 Joined: 20-April 05 Member No.: 321 |
The velocity of 'Oumuamua is far beyond the escape velocity of the Sun. There is no circumstance of orbital mechanics in our solar system that could accelerate an object that was initially in solar orbit to this velocity.
|
|
|
Lo-Fi Version | Time is now: 5th June 2024 - 05:46 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |