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Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

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Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#71
post #68

Earlier quoted context omitted.

What I meant was, the origin of the object may have been in a different inertial frame of reference to our solar system, so the 'spin' as far as it is concerned is not spin.

This is not a thing though. Spin is spin, regardless of reference.

I really misunderstand my relativity then.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#72

I am truly surprise that we don't get more interstellar visitors into our solar system. It kind shows how small our solar system is, or other way, how big the universe is.

There's a good chance these sorts of things are whizzing past us all the time, and we're just not detecting them. I mean, we just discovered ten new moons of Jupiter this year: http://earthsky.org/space/10-new-moons-discovered-jupiter-1-...

And two the year prior, bringing the count to 12 since 2016, for a total of 79 moons around Jupiter.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#73
post #50
post #17

Earlier quoted context omitted.

This has always fascinated me. We can actually build giant spaceships (space stations) inside asteroids and use them for interstellar travel. All the resources we need, including ice would be at our disposal. Like traveling with your own mini-planet. Dirk Schulze had taken that as a subject into his sci-fiction book - Alien Encounter.

From an energy perspective, it's likely better to build your own station (from an asteroid - or alternative, remove all the mass from the asteroid that you don't need) - that way, you're only accelerating exactly the mass that you need, not wasting any energy accelerating the rest of an asteroid.

If it's a space station, then accelerating it is less of a concern than keeping it livable, and a huge amount of matter surrounding you goes a long way to protect you from things that would otherwise kill you.

Now for a space ship, I agree. Though even then you might benefit from that extra matter in the same way.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#74

Earlier quoted context omitted.

I prefer a complementary theory -- that it's a spent stage of a multi-stage spacecraft. If the primary stage were decelerating for a rendezvous with Earth, then any stage that made it to full acceleration would reach us first, probably getting close and then flinging back out of the solar system, just like this did. Easy enough to test -- we'll eventually see another object following the same trajectory, give or take…

"And on far-off Earth, Dr. Carlisle Perera had as yet told no one how he had wakened from a restless sleep with the message from his subconscious still echoing in his brain: The Ramans do everything in threes."

For anyone curious as I was, this is a quote from "Rendezvous with Rama" by Arthur C. Clarke.

https://www.wikiwand.com/en/Rendezvous_with_Rama

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#75
post #68

Earlier quoted context omitted.

This is not a thing though. Spin is spin, regardless of reference.

I really misunderstand my relativity then.

You seem to know that the rules of physics should hold in any inertial (i.e. non-accelerating) reference frame. But the thing you missed is that a spinning reference frame cannot be inertial. There is centripetal acceleration when something spins.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#76
post #68

Earlier quoted context omitted.

This is not a thing though. Spin is spin, regardless of reference.

I really misunderstand my relativity then.

You've got the right general idea, but the principle of relativity only applies to constant velocity motion. If two astronauts float past each other in space, either of them can claim that they're motionless and the other is moving past them. However, if one of them is accelerating or spinning, they'll both agree on who it is.

https://en.wikipedia.org/wiki/Principle_of_relativity

https://en.wikipedia.org/wiki/Inertial_frame_of_reference

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#77
post #15

Earlier quoted context omitted.

What’s special about 0.163 AU? Does it have a mathematical significance?

Just that it's unusually close.

There is a bit of sampling bias, given that we are looking for space objects from Earth, and so it easier to detect something that comes closer to Earth. Not sure how significant the bias is for an object of this size and speed, but I'm guessing that it is probably a relevant factor.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#78

Earlier quoted context omitted.

Great series of books! Every time I see a thread about this big rock I think of Rama.

Beg to differ. Great book. Awful cheap hacks posing as sequels. I regret reading them - they've nearly ruined the original for me.

The final reveal was mind-numbingly bad.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#79

Earlier quoted context omitted.

Great series of books! Every time I see a thread about this big rock I think of Rama.

Beg to differ. Great book. Awful cheap hacks posing as sequels. I regret reading them - they've nearly ruined the original for me.

My personal theory is that Clarke's writing partners sedated and tied him inside a closet until the book was finished.

That's the only way to explain how awful some of his last books were.

Having said that, I liked Richter 10. Too bad the co-author died before they could write another one.

Re: Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

#80
post #3

I'm still convinced this is an alien probe. I mean look at that trajectory. 0.163 AU from Earth - what are the odds? The spinning is irrelevant surely - I mean, it's all relative, so as far as ’Oumuamua is concerned, we're spinning. Maybe it was spinning that way to stay aligned with a distant companion for communication.

I prefer a complementary theory -- that it's a spent stage of a multi-stage spacecraft. If the primary stage were decelerating for a rendezvous with Earth, then any stage that made it to full acceleration would reach us first, probably getting close and then flinging back out of the solar system, just like this did. Easy enough to test -- we'll eventually see another object following the same trajectory, give or take…

Maybe it was intended to be a booby trap for the Zentraedi?
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