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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

#111

Post by walrus01 »

hannasanarion wrote: post #48
walrus01 wrote: post #23

Earlier quoted context omitted.

There is fairly strong consensus in the astronomy community that possibly hundreds of Sednoid class objects exist, and those are in relatively normal orbits compared to things which are beyond solar escape velocity. But so far we've only found 3 or 4 Sednoids. https://en.m.wikipedia.org/wiki/Sednoid

Sednoids orbiting in the kuiper belt are totally different from extrasolar objects on hyperbolic trajectories. Oamuamua passed inside Mercury's orbit.

Yes, but both classes of objects are very dificult to detect, due to distance, size and lack of brightness. We only detected the extrasolar object once it had already passed perihelion and was on its way out.

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

#112

Post by InclinedPlane »

Balgair wrote: post #108
InclinedPlane wrote: post #107

Earlier quoted context omitted.

Good point. One thing we learned from exoplanet hunting is that there is a much greater diversity out there than we had originally thought, implying that planet formation is a lot more of a dynamic process than our previous models indicated. Prior to the discovery of exoplanets our planet forming models were very much "over fit" to the example of our own Solar System, giving the impression that other stellar systems…

I have close friends working on Psyche! You are right that our understanding of small bodies is going up very quickly, it's quite exciting (in asteroid terms) to be alive now; a lot is being answered and re-questioned with actual evidence. Hopefully (knock on wood) JWST gets up there soon and a LOT more questions can be answered. One issue we have is that there is this 'gap' in planet formation modeling. We can figur…

Awesome! I'm constantly bummed out about the failure of the CONTOUR mission, I can only imagine what we'd know now. Psyche is one of the coolest missions in the pipeline though, it's kind of crazy how fast our knowledge of small bodies is growing.

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

#113

Post by burke »

sjclemmy wrote: post #109
burke wrote: post #102

Earlier quoted context omitted.

To add on to this, here's a simple thought experiment to explain why spinning is different from constant velocity: Imagine you're off somewhere space. You're holding a ball in each hand. 1. You're motionless with reference to the Earth. You let go of the balls. They stay put. 2. You're moving away from the earth with a constant velocity. You let go of the balls. They continue to move at the same velocity as you do: T…

I’m really interested in understanding this. So please indulge me... So, I’m Oumuamua rocking my way through interstellar space. I see nothing around me so as far as I know I’m not spinning. Then, all of a sudden I happen upon a solar system that is spinning around me. Who is spinning? Me or the solar system? Is the point here that I’m spinning with reference to my direction of motion?

Yes. You are aware that you are spinning even without external reference because your outer parts are accelerating toward your inner parts. This is the feeling of spinning in a circle on earth too.

This is how plausible simulated gravity works too. A ship spins. It doesn’t require a reference to know whether it’s spinning.

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

#114

Post by ecnahc515 »

dmix wrote: post #72
ceejayoz wrote: post #70

Earlier quoted context omitted.

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.

How many moons are discovered per-year on average? Is there something about these recent ones that made it difficult to discover earlier, eg size?

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

#115

Post by westurner »

newnewpdro wrote: post #46
holografix wrote: post #34

Earlier quoted context omitted.

Wouldn’t such an object be emitting radio signals that earth could receive?

Not if it's something like another civilization's Tesla Roadster.

> Not if it's something like another civilization's Tesla Roadster.

'Oumuamua is red and headed toward Pegasus (the winged horse) after a very long journey starting longtime in spacetime ago. It is wildly tumbling off-kilter and potentially creating a magnetic field that would be useful for interplanetary spacetravel.

They're probably pointing us to somewhere else from somewhere else.

If this is any indication of the state of another civilization's advanced physics, and it missed us by a wide margin, they're probably laughing at our energy and water markets; and indicating that we should be focused on asteroid impact avoidance (and then we will really laugh about rockets and red electromagnetic kinetic energy machines and asteroid mining). https://en.wikipedia.org/wiki/Asteroid_impact_avoidance

"Amateurs"

[We watch it fly by, heads all turning]

Maybe it would've been better to have put alone starman in the passenger seat or two starpeoples total?

Given the skull shape of October 2015 TB145 [1] (due to return in November 2018), maybe 'Oumuamua [2] is a pathology of Mars and an acknowledgement of our spacefaring intentions? Red, subsurface water, disrupted magnetic field.

[1] https://en.wikipedia.org/wiki/2015_TB145

[2] https://en.wikipedia.org/wiki/%CA%BBOumuamua

In regards to a red, unshielded, earth vehicle floating in solar orbit with a suited anthropomorphic creature whose head is too big for the windshield:

"What happened here?"

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

#116

Post by westurner »

westurner wrote: post #115
newnewpdro wrote: post #46

Earlier quoted context omitted.

Not if it's something like another civilization's Tesla Roadster.

> Not if it's something like another civilization's Tesla Roadster. 'Oumuamua is red and headed toward Pegasus (the winged horse) after a very long journey starting longtime in spacetime ago. It is wildly tumbling off-kilter and potentially creating a magnetic field that would be useful for interplanetary spacetravel. They're probably pointing us to somewhere else from somewhere else . If this is any indication of th…

"That's not a knife... This is a knife." -- Crocodile Dundee

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

#117

Post by DaveSapien »

DaveSapien wrote: post #18

Would gravitational pull account for the acceleration? Meaning if it were made (or part of it) of some very dense element like Iridium, there would be an unexpected attraction to our sun?

Thanks for your comments, they have kicked me out of my head space. I suppose I got it into my head thinking of massive densities, like densities of neutron star. Anything dense enough to make a difference would be very loud and easy to spot... as I'm writing this, even if it were very dense. The effect would only be seen when it is much closer to another gravity well. Ok, how about this (I'm still stuck on this gravity idea), there is an unseen "cloud" of rock orbiting (very) slowly round the main body. Seemingly slowing down and accelerating as it orbits. A small body or cloud of bodies could easily be small enough for us to not see it, but enough to cause this effect. Sound reasonable?

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

#118

Post by jimijazz »

krapp wrote: post #86
jimijazz wrote: post #62

Earlier quoted context omitted.

I wouldn't be so sure we don't... Just because we don't see them with our 5 senses doesn't mean they are not here yet.

You do realize we're not limited to "our 5 senses" when studying the universe, right?

You're totally right. I actually didn't think of that, but just meant that maybe other forms of being could exist and manifest in dimensions we're not even looking at. Is that why my comment was downvoted?
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