>almost undoubtedly the largest Oort Cloud object ever discovered- almost in dwarf planet territory!
Not a dwarf planet.
A dwarf planet coming within 11 AU of the sun over the next 10 years
121–130 of 330 posts
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#122Earlier 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.
I've been aware of people talking about Kerbal Space Program for years and years, but I lost interest in playing it when I heard it didn't do real N-body gravitational calculations because they were too intensive.
I still find that inexplicable. To me, it sounds like saying "our calculator only does basic arithmetic on four core machines, square roots are too slow".
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#123For 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.
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.)
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#124Apologies if this is an obvious question but I'm not familiar with astronomy. Will this dwarf planet just pass through our solar system or is there a chance it will start to orbit our sun?
> its orbit takes it from just beyond the orbit of Saturn (10.9 AU) all the way out to the Oort Cloud It looks like it currently orbits the sun.
According to the link, the outgoing aphelion will be almost 40% more than the previous one, so I wouldn't assume it's going to orbit indefinitely.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#125For 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.
Is it possible to get a probe out that far in time to make a good intercept?
I imagine with this (relatively) short notice this is cutting it a bit close to orchestrate a proper orbital insertion by a designed, manufactured and tested program?
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#126Earlier quoted context omitted.
Seriously, the tandem failures of the Mars Polar Lander and Mars Climate Observer missions were probably something NASA as an organization needed at the time. A reminder that Space Is Hard, and you can only pick two of "faster", "better", and "cheaper". Since then, NASA's Mars program has grown in both scope and ambition, yet remarkably has had zero loss-of-mission failures during that whole time!
I was referring to the successful landing of Pathfinder but yeah... Space is Hard and NASA is good at it are both very true.
Most of the velocity of Pathfinder was shed using aerobraking and parachutes. The crash-balloon landing system just shed the last tiny sliver of velocity after cutting the chutes.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#127Earlier quoted context omitted.
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.
I've been aware of people talking about Kerbal Space Program for years and years, but I lost interest in playing it when I heard it didn't do real N-body gravitational calculations because they were too intensive. I still find that inexplicable. To me, it sounds like saying "our calculator only does basic arithmetic on four core machines, square roots are too slow".
Not really that inexplicable, it’s a video game. It’s not for computational reasons, but to make gameplay easier to reason about; because again, it’s a video game.
The mechanics are simplified, yes, but patched conics is quite a good approximation for many cases, and great for developing an intuition for the basics.
There is a mod that includes n-body calculations called Principia if you’re interested in that.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#128Earlier quoted context omitted.
How come our culture didn’t base astronomical units around base 10 of our current units?
It's an old unit, so there wasn't a global standard yet, and it's exact value wasn't known for a long time, but it was still useful for ratios. E.g. if you observe the orbit time of another planet, you can tell its distance from the sun relative to the distance of Earth to Sun (1 astronomical unit) relatively accurately, even if you can't measure what it is in meters very well.
For my purposes 10 AU has a lot more meaning than 1 billion km. 1 AU has a lot more context
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#129Earlier quoted context omitted.
Apparently no one likes this idea. Here's mine: we nuke the planet and collect its smitherines for SCIENCE!
Let's send some boosters out there, redirect it to earth, and make a second moon. Come on people, what ever happened to doing shit cause its fuckin' rad, do you know how cool another moon would be?!
Constructive interference from multiple tidal waves could flood huge coastal areas, killing or displacing millions. Uncool.
Re: A dwarf planet coming within 11 AU of the sun over the next 10 years
#130Earlier quoted context omitted.
It's expected orbit will take it around 54,600 AU from the Sun. The orbital period of something that far out is in the millions of years range. If it doesn't kill us this time, rest assured by the time it comes back we'll have done the job properly already.
I'm more referring to objects of this kind, not this specific object. Threats from supercomets are not a new concern: https://academic.oup.com/mnras/article/448/1/27/990672 "A 100 km comet striking the Earth would carry ∼1000 times the energy involved in the creation of the 150 km Chicxulub crater and would presumably remove the surface biosphere"
I think people have suggested the dinosaur killing asteroid may have caused global fires and rain of molten rock, so that scale might be sufficient as far as humans are concerned.