Is that Nibiru?
Too small, maybe a generation ship on approach?
A dwarf planet coming within 11 AU of the sun over the next 10 years
101–110 of 330 posts
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#102For reference 1 AU (Astronomical Unit) is about 150 million km. Saturn ranges from being about 7 to 11 AU away from Earth. Voyager 1 is 152 AU away. This object is excitingly close and will be fun to study.
I don't think Saturn comes that close, should be 8 AU at best, given that perihelion is at 9 AU.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#103This 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…
I've always figured there's no point in worrying about giant planet destroying meteors, if one comes and we can't stop it, well we're all fucked. What can ya do at that point? If it can't be stopped and it can't be changed...well I guess we had a decent ride...at least it'll probably look cool before we're all vaporized.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#104Earlier quoted context omitted.
It won’t do anything. Also, Carrington class events are very rare. You should worry more about space junk crashing into important things and even then it’s not much of a worry. https://warwick.ac.uk/newsandevents/pressreleases/likelihood...
> The analysis shows that ‘severe’ magnetic storms occurred in 42 out of the last 150 years, and ‘great’ super-storms occurred in 6 years out of 150 That seems extremely imminent, like in my lifetime. How many of these events would shut down tech for months or years? Are those odds worth risking civilization over?
Sever might not be so dangerous
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#105Earlier quoted context omitted.
Yes, this is an aspect of orbital mechanics that people find unintuitive before they study it. You can't be captured by a planet's gravity alone. If you come in from infinity (i.e., not already captured) you will escape to infinity (remain not captured). The basic idea can be seen from the fact that gravitational dynamics are time-reversible, so if gravity could capture you like this you could also start in orbit aro…
It can reduce the delta-V requirements, though - by the same principles as a gravity assist, a capture burn (especially into a loosely-bound planet-centric orbit) often takes less work than burning into the equivalent heliocentric orbit on your own.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#106Is this something we could plan and manage to launch an orbiter/lander to in time? Has anyone thought about the possibility of slapping something like a telescope on that and letting it beam back data and images from veryyyyy far out eventually?
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#107Earlier quoted context omitted.
I've always figured there's no point in worrying about giant planet destroying meteors, if one comes and we can't stop it, well we're all fucked. What can ya do at that point? If it can't be stopped and it can't be changed...well I guess we had a decent ride...at least it'll probably look cool before we're all vaporized.
What if it can be stopped in theory, but only if humanity pulls together and gets something right for once?
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#108Earlier quoted context omitted.
That's pretty cool. It's wildly counterintuitive, but if it weren't the case, the planets would be orbited by lots of captured asteroids and debris, instead of/in addition to being covered in craters. The only explanation for why that doesn't happen is that it can't happen.
The presence of natural satellites indicates this can indeed happen. It just requires a pretty unlikely orbital configuration.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#109Earlier quoted context omitted.
The speed of Rosetta's comet at perigee is, I think, significantly grater than the max speed of this dwarf planet. The dwarf planet has a much higher apogee, of course, but escape velocity, corresponding to infinite apogee, is finite and not that large, and Rosetta had to go much deeper into the Sun's gravity well. So, as a non-expert who hasn't done the numbers, I'd guess matching pace with the dwarf planet would be…
Somewhat unintuitively, thanks to the Oberth effect, it can be easier to reach escape velocity closer to an object, (Humorously portrayed in https://xkcd.com/1242 ). Aside: if you are looking to learn more, I cannot recommend Kerbal Space Program enough.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#110Earlier quoted context omitted.
I've always figured there's no point in worrying about giant planet destroying meteors, if one comes and we can't stop it, well we're all fucked. What can ya do at that point? If it can't be stopped and it can't be changed...well I guess we had a decent ride...at least it'll probably look cool before we're all vaporized.
What if it can be stopped in theory, but only if humanity pulls together and gets something right for once?