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A dwarf planet coming within 11 AU of the sun over the next 10 years

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Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#221

Post by tmp538394722 »

XorNot wrote: post #214
monkeycantype wrote: post #186

Earlier quoted context omitted.

Is it a comety composition? Crash it into mars for some ocean and atmosphere?

I keep hoping we'll get lucky in my lifetime and something big like that will just hit Mars on it's own. It would be a hell of a world to go from "desert" to "so we've got all these new oceans to name and also you can't breathe it but ground level pressure is one atmosphere".

I think seeing something world changingly large randomly smashing into our next door neighbor would leave me feeling something other than lucky.

But sure if it’s gonna happen, let’s get the neighbors a pool! Just let me uh… change my shorts.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#222

Post by [deleted] »

messe wrote: post #184
sneak wrote: post #178

Earlier quoted context omitted.

What sort of propulsion mechanisms (even those that are currently physically plausible but entirely outside our technology, so, for example, solar sails or nuclear torchships, but not, say, warp drive) could possibly be used to achieve such a task?

Nuclear would do it. Essentially use the dwarf planet itself as reaction mass, accelerating it with either nuclear thermal propulsion or a nuclear powered mass driver. Highly impractical, and would take centuries to slow it down enough.

[deleted]

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#223

Post by shkkmo »

Armisael16 wrote: post #152
shkkmo wrote: post #73

Earlier quoted context omitted.

> You can't be captured by a planet's gravity alone Technically, this isn't completely true. There are gravity assist techniques that will allow you to dump speed by essentially adding your momentum to the object you are trying to orbit. The is basically an anti-slingshot manuever. In practice, I believe the range of scenarios when this is possible with a dwarf planet is so small as to be practically useless.

In a two-body system it doesn’t matter what you do; gravity is a conservative force so conservation of energy demand that you leave the body’s SoI at the same speed you entered it (in the body’s frame of reference). You can lose speed or alter course relative to another body in a single encounter, and those changes can reduce speed in future encounters, but if you’re on an escape trajectory heading in you stay in one…

> In a two-body system it doesn’t matter what you do;

Two-body systems do not exist in reality.

Energy is also conserved in 3 body problems. When you utilize the slingshot effect, some of the energy of the orbit of the body you are swinging around orbiting is transfered to you. The transfer of this energy does not depend on the closeness of the sun, but rather on how deeply you descend into the gravity well of the object you are slingshotting around.

> which is a pretty safe assumption 11 AU out of Saturn doesn’t come close

No, it really isn't. The "safeness" of the assumption entirely depends on your margin for error. The existence of the naturally captured saturnian satellites clearly indicates that you are simply wrong about the relevant margins for error.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#224

Post by earthboundkid »

edgyquant wrote: post #192
op00to wrote: post #161

Earlier quoted context omitted.

Nope. I say your-anus.

You might but that is an incorrect pronunciation and the only time I’ve heard that (other than from people who aren’t into astronomy) was in elementary school and even then the teacher told us it was a common, but wrong, pronunciation.

A thread of people discussing pronunciations without saying where they are from or using IPA is a pointless waste of time. You may as well be talking about what time it is by posting “well, it’s dark here!”

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#225

Post by retsibsi »

edgyquant wrote: post #123
grawprog wrote: post #90

Earlier quoted context omitted.

So pretty much between Saturn and Uranus.... Even as an adult that still always makes me chuckle. I can't help it.

It’s pronounced your-uh-ness by pretty much everyone (or your-ah-noose if your going by the greek god and not the Latin copy/paste.)

I think "pretty much everyone" is an exaggeration. Google's pronunciations (British and US) are both the 'anus' version -- though the British one has a secondary stress on the first syllable, rather than the schwa of the US version.

Growing up in Australia, the British 'you-ray-nəs' (i.e. not quite 'your anus', but only because of the first vowel sound) is the pronunciation I was familiar with. Lately I've heard 'you-rə-nəs' fairly often, but not exclusively.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#226

Post by hodgesrm »

tshaddox wrote: post #216
lumost wrote: post #215

Earlier quoted context omitted.

I'm not sure how the mechanics of a 200 km wide comety like object hitting Mars at ~25 km/s would work out, but I'm reasonably certain that it would result in a major resurfacing event. I'd venture that the majority of the gasses would retain escape velocity following impact.

Well, since we’re just assuming we could meaningfully change it’s trajectory we might as well also assume we could slow it down!

Slowing it down would take way more energy than just nudging in a different direction. You might be better off trying to break it up into smaller pieces.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#227

Post by retsibsi »

earthboundkid wrote: post #224
edgyquant wrote: post #192

Earlier quoted context omitted.

You might but that is an incorrect pronunciation and the only time I’ve heard that (other than from people who aren’t into astronomy) was in elementary school and even then the teacher told us it was a common, but wrong, pronunciation.

A thread of people discussing pronunciations without saying where they are from or using IPA is a pointless waste of time. You may as well be talking about what time it is by posting “well, it’s dark here!”

Location/accent is important, but sometimes we can get by without IPA. There will be some ambiguity, but often we're sufficiently familiar with each other's accents to interpret phonetic spellings as intended. (Though I do think the ə symbol is indispensable, because representing the schwa sound with 'uh' is just confusing.)

edit: sorry, just realised I probably misread you (as saying we should say where we're from and use IPA), in which case this comment is redundant.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#228

Post by Mountain_Skies »

lmilcin wrote: post #166
bnjemian wrote: post #162

I say we catch that sucker, tow it into our neck of the woods as a second moon, and use it as a space port. Are there a million problems with this proposal? Yes. But would it be totally rad to do this? Also yes.

But why? Don't we already have a moon?

Think of all of the opportunities to write software to calculate the complicated changes required for astrology.

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#229

Post by peeters »

sneak wrote: post #178
bnjemian wrote: post #162

I say we catch that sucker, tow it into our neck of the woods as a second moon, and use it as a space port. Are there a million problems with this proposal? Yes. But would it be totally rad to do this? Also yes.

What sort of propulsion mechanisms (even those that are currently physically plausible but entirely outside our technology, so, for example, solar sails or nuclear torchships, but not, say, warp drive) could possibly be used to achieve such a task?

Scott Manley had a recent video talking about the work involved in moving the Earth, that you might find interesting. Basically the most "plausible" approach might be to move the moon and use it to drag the Earth. Similarly the best way to move another large object might be to carefully move other objects small amounts to do precise gravity assists.

https://youtu.be/5StYppuJ_lg

Re: A dwarf planet coming within 11 AU of the sun over the next 10 years

#230

Post by slowmovintarget »

pfdietz wrote: post #89

This is actually terrifying. That body is on a cometary orbit, and need not be stable long term. If it's chaotically pushed around by the major outer planets it might get sent into an orbit that gets into the inner solar system. And if something that size hit Earth, it would be game over for life here -- the impact would vaporize much or all of the oceans. Even an impact by something the size of comet Hale-Bopp would…

Seems more likely that what has happened before will happen again, which is to say that Jupiter or Saturn pull it apart into asteroids and perhaps new moons.

Jupiter's orbit is roughly five AUs, and Saturn's orbit is at roughly ten, and in those regions, they have enormous influence on where stuff gets to go in the solar system.

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