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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

#61

Post by Sharlin »

perihelions wrote: post #50
Sharlin wrote: post #31

Earlier quoted context omitted.

I believe this is absolute magnitude, and specifically, absolute magnitude as defined for comets [1]. At Saturn's distance, definitely not a naked-eye object in any case. [1] https://en.wikipedia.org/wiki/Absolute_magnitude#Cometary_ma...

Not in this case: the +13 figure is a predicted *apparent* magnitude. The absolute magnitude 'H' as your link defines is the 'H' field in the OP link, which is +7.8. (Note that's 'H' from your link's section on asteroid magnitudes, not comets or stars -- they're all on different scales). Here's the documentation for the fields in OP's data table: "H Absolute visual magnitude. A table converting H to a diameter is ava…

Ah, thanks. So its H_asteroid is currently +7.8, and if/when it develops a coma it should become a lot brighter, but unfortunately even at perihelion still way too faint for a naked eye.

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

#62

Post by fouronnes3 »

Sharlin wrote: post #58
tmhrtly wrote: post #57

Earlier quoted context omitted.

What if we crash landed into it? That would probably tick the irreversible box. Clearly engineering difficulties quite high though!

This is often jocularly called lithobraking and is typically not advisable.

> not advisable

Unless you're NASA landing a probe on Mars in 1997.

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

#63

Post by mcorning »

lopuhin wrote: post #59
mcorning wrote: post #13

For 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.

https://www.universetoday.com/15311/how-far-is-saturn-from-e...

> For the sake of simplicity, Saturn is 1.2 billion km, roughly 7 AU, from the Earth when the two are at their closest approach to one another. They are 1.67 billion km, around 11 AU, from each other when they are at their most distant. Saturn and Earth are the closest to each other when they are on the same side of the Sun and at similar points in their orbits. The are the most distant when on opposite sides of the Sun.

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

#64

Post by ehsanu1 »

tmhrtly wrote: post #57
jessriedel wrote: post #53

Earlier 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…

What if we crash landed into it? That would probably tick the irreversible box. Clearly engineering difficulties quite high though!

It's a cool idea, but seems super sci-fi. Might need some wonder materials to make it feasible, even then that would be a really big crumple zone. Or flubber. Another crazy idea: latch on to the planet from the side, like a skateboarder hitching a ride by hanging on to a truck. Again, wonder materials required.

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

#66

Post by CamperBob2 »

jessriedel wrote: post #53
tonmoy wrote: post #38

Earlier quoted context omitted.

Is that really true? If we manage to get a spacecraft get captured by the dwarf planet's gravity and orbit it, would that not be a lot less delta-V compared to if we made the spacecraft achieve the dwarf planet's orbit around the sun just by itself?

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…

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.

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

#67

Post by f6v »

floatrock wrote: post #44
anfilt wrote: post #28

Earlier quoted context omitted.

Like till it gets closer we dont even know if it would be suitable to put something like that on it. Although it does seem like interesting idea. However, we have sent probes much further than this object (aka the voyager missions). So it would mainly be useful for studying this object. So a telescope would be less than ideal since we could always in theory deploy a telescope much deeper into space if we wanted.

Interestingly, the voyager missions were also timed-events -- they were launched when they were because JPL realized it was a 1-in-175-year alignment of the outer planets that made it feasible to launch just a few crafts to visit the outer planets all in one go: https://en.wikipedia.org/wiki/Grand_Tour_program

AFAIK many launches are timed to make the flight shorter. Although not on 1 in 175 years, but shorter windows.

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

#68

Post by f6v »

015a wrote: post #56
c3534l wrote: post #52

Earlier 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?!

Let’s just blow the moon up and give rise to 7 new genetically engineered races, man-fishes, and dwarves.

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

#69

Post by simonh »

0-_-0 wrote: post #46
jbay808 wrote: post #36

Earlier quoted context omitted.

Could you get a nice gravity boost away from the sun by just following it for as long as possible?

I think it should provide a much stronger slingshot velocity boost than any other planet, however getting to 11AU first is not easy. https://en.wikipedia.org/wiki/Gravity_assist

The magnitude of the slingshot boost increases with the mass of the planetary body. This thing is smaller than any of the planets so you’d get a much smaller boost. The best planet for slingshotting from is Jupiter because it’s the most massive.

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

#70

Post by azernik »

jessriedel wrote: post #53
tonmoy wrote: post #38

Earlier quoted context omitted.

Is that really true? If we manage to get a spacecraft get captured by the dwarf planet's gravity and orbit it, would that not be a lot less delta-V compared to if we made the spacecraft achieve the dwarf planet's orbit around the sun just by itself?

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.
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