Author Topic: New Horizons updates  (Read 237906 times)

Offline hoku

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Re: New Horizons updates
« Reply #700 on: 02/08/2019 09:47 pm »

Offline FutureSpaceTourist

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Re: New Horizons updates
« Reply #701 on: 02/08/2019 10:01 pm »
« Last Edit: 02/08/2019 10:02 pm by FutureSpaceTourist »

Online indaco1

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Re: New Horizons updates
« Reply #702 on: 02/09/2019 08:08 am »
I know I'm saying something stupid but the only natural process I recall that give rounded but not spherical objects is erosion.

Could this be the result of slow speed impacts when the main pieces don't stay in contact after the impact?

Sometimes colliding objects stay in contact, like Ultima and Thule, sometimes they are just eroded, it depends by speed, direction, geometry, adhesiveness and other parameters.
Non-native English speaker and non-expert, be patient.

Offline Jaroslav

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Re: New Horizons updates
« Reply #703 on: 02/11/2019 08:02 am »
I have a silly idea. What if the smaller asteroid originates from inside of the bigger? Something happened that forced the inner material to eject outside and the asteroid became flat.
« Last Edit: 02/11/2019 08:08 am by Jaroslav »

Offline Paul451

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Re: New Horizons updates
« Reply #704 on: 02/11/2019 10:07 am »
I have a silly idea. What if the smaller asteroid originates from inside of the bigger? Something happened that forced the inner material to eject outside and the asteroid became flat.

{laughs} Asteroidal mitosis.

Offline Eric Hedman

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Re: New Horizons updates
« Reply #705 on: 02/11/2019 02:00 pm »
This brings up some interesting questions.

Were the two lobes flat before they came into contact with each other?  If they were, what are the odds they would make contact on edge with each other and stay in that position?

Is a flat disk a common shape for Kuiper Belt objects?

If the objects were round when they made contact, what happened to the material that was worn off?  If the excess material is not there does that prove they were disk shaped before contact?

Offline ugordan

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Re: New Horizons updates
« Reply #706 on: 02/11/2019 02:12 pm »
Is a flat disk a common shape for Kuiper Belt objects?

This is like the first ever KBO we've seen up close that is small enough not to have been deformed into hydrostatic equilibrium.

Offline Paul451

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Re: New Horizons updates
« Reply #707 on: 02/11/2019 03:59 pm »
This brings up some interesting questions.
Were the two lobes flat before they came into contact with each other?  If they were, what are the odds they would make contact on edge with each other and stay in that position?

There are moons in Saturn's ring that show such flattening, caused by the accumulation of dust in the plane of the ring. Modelling suggests that dust/ice clouds, due to their internal interaction, tend to flatten into a clean equatorial ring. Two objects formed of such a process would be in the same plane, by default. That suggests a similar process for UT. But... ring around what?

Offline Jaroslav

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Re: New Horizons updates
« Reply #708 on: 02/12/2019 11:22 am »
I know it is silly, but maybe if a small asteroid somehow punched hole into the big asteroid and exploded inside, it could lead to escaping of the inner material through the hole outside, where it became solid again. The underpressure caused by the escaped material would cause the asteroid become flat.
« Last Edit: 02/12/2019 11:24 am by Jaroslav »

Offline Kaputnik

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Re: New Horizons updates
« Reply #709 on: 02/12/2019 05:01 pm »
Would it be possible for a very loosely bound object to flatten out by gradual flowing of particles towards the equator, caused by the centrifugal force of its own spin?
I have no explanation for how such a delicate object could survive contacting another one of the same type, though...
Waiting for joy and raptor

Offline vandersons

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Re: New Horizons updates
« Reply #710 on: 02/12/2019 05:58 pm »
If flat things form when there are rings around could it be that in the early solar system there were actual rings of dust and ice that far out. I mean a ring system around the Sun where the current Kuiper belt objects reside.

Any models out there showing anything like that? Yhe resemblence to Saturn's 'pancake moons' is striking.

Offline libra

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Re: New Horizons updates
« Reply #711 on: 02/12/2019 06:48 pm »




Look ma ! A religieuse cake from outer-space !

Online zubenelgenubi

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Re: New Horizons updates
« Reply #712 on: 02/12/2019 08:43 pm »
A few thoughts shared at today's Tuesday astronomy journal lunch (at work), which I'll try to paraphrase correctly:

Re: formation.  Could be a three-body problem, with momentum transferred to the 3rd object, which would have been ejected from the "system."  The remaining pair would be left to collide with a low relative velocity, which would allow a very inelastic "sticking" collision; not a fragmentation.

What are the dynamic statistics for such a collision?  No answer yet--very small sample size (1).

These two lobes are well below the mass to force hydrostatic equilibrium, individually or cumulatively.  What if this pancake shape is statistically common for KBOs?

Is there a connection between the "odd" shape of the two lobes and the "odd" shape of 1I/?  (Similar accretion in two different protoplanetary systems?)
« Last Edit: 02/12/2019 08:58 pm by zubenelgenubi »
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Offline Zed_Noir

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Re: New Horizons updates
« Reply #713 on: 02/13/2019 03:13 am »
A few thoughts shared at today's Tuesday astronomy journal lunch (at work), which I'll try to paraphrase correctly:
....
These two lobes are well below the mass to force hydrostatic equilibrium, individually or cumulatively.  What if this pancake shape is statistically common for KBOs?
....

There is only one way to solve this. We need to have close look at more KBOs.  ;)

Think for this option to be possible. You need a non-RTG power option for at least a few dozen Kuiper Belt probes needed for the close looks. There isn't enough Pu238 available anytime soon except for maybe a half handful outer system probes.

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