# new, better images of Ultima Thule

sonhouse
Science 26 Jan '19 17:14
1. sonhouse
Fast and Curious
26 Jan '19 17:14
https://spaceflightnow.com/2019/01/25/ultima-thule-revealed-in-new-detail-with-fresh-flyby-image/

I wonder if we can calculate a range of physical force needed to separate the two lobes (not that that would ever happen but just an interesting physics problem) if there was not some kind of rock welding going on where the two bodies are just basically touching and not melted together since it seems the collision was very gentle.
2. 27 Jan '19 15:26
@sonhouse said
https://spaceflightnow.com/2019/01/25/ultima-thule-revealed-in-new-detail-with-fresh-flyby-image/

I wonder if we can calculate a range of physical force needed to separate the two lobes (not that that would ever happen but just an interesting physics problem) if there was not some kind of rock welding going on where the two bodies are just basically touching and not melted together since it seems the collision was very gentle.
So it's not an eggplant?
3. sonhouse
Fast and Curious
27 Jan '19 15:39
@wildgrass

And so far, no green cheese
4. joe shmo
Strange Egg
27 Jan '19 18:14
@sonhouse
In the case where they are not fused and the system has no angular momentum which is believed to be the case from your article. You must overcome the force of gravitation. Your going to need to know the average density (assuming its pretty uniform).
5. sonhouse
Fast and Curious
27 Jan '19 18:54
@joe-shmo said
@sonhouse
In the case where they are not fused and the system has no angular momentum which is believed to be the case from your article. You must overcome the force of gravitation. Your going to need to know the average density (assuming its pretty uniform).
We could make some assumptions like the rocks of Ultima have the same density as say limestone or granite which I would have to gargle to find those numbersðŸ˜‰
Then the size, or total volume and thus the mass of each one. Can't be all that much, My guess is you could pry the two pieces apart with a crowbar.....
6. joe shmo
Strange Egg
27 Jan '19 20:31
@sonhouse

It would be that, a guess. We don't know what the core is, maybe solid iron, maybe loose rocks and dust. But the article gives all the other necessary measures.

The lobes are approximately spherical.
The longest dimension is about 21 miles.
The larger lobe is about 2.6 time the volume of the smaller lobe.

Those and the density are all we need to come up with an approximation.
7. sonhouse
Fast and Curious
28 Jan '19 16:28
@joe-shmo said
@sonhouse

It would be that, a guess. We don't know what the core is, maybe solid iron, maybe loose rocks and dust. But the article gives all the other necessary measures.

The lobes are approximately spherical.
The longest dimension is about 21 miles.
The larger lobe is about 2.6 time the volume of the smaller lobe.

Those and the density are all we need to come up with an approximation.
It's too bad the probe flew by 4000 miles way from Thule, if it had gone say 10 miles from the surface, you could track the change in orbital directions to calculate the mass directly but I don't think they have much of a handle on the mass of this contact binary. At 4000 miles from a body only 10 or 20 miles across I would imagine you would have to have a micrometer to measure the change in trajectory of the probeðŸ˜‰
8. 28 Jan '19 20:52
@sonhouse said
It's too bad the probe flew by 4000 miles way from Thule, if it had gone say 10 miles from the surface, you could track the change in orbital directions to calculate the mass directly but I don't think they have much of a handle on the mass of this contact binary. At 4000 miles from a body only 10 or 20 miles across I would imagine you would have to have a micrometer to measure the change in trajectory of the probeðŸ˜‰
Will this thing still be transmitting when it goes interstellar? Why haven't we launched 100 of these?
9. sonhouse
Fast and Curious
29 Jan '19 02:20
@wildgrass said
Will this thing still be transmitting when it goes interstellar? Why haven't we launched 100 of these?
Maybe the one billion dollar price tag has something to do with it. That and the lucky alignment of planets that allowed that journey. I guess though that kind of trajectory can be calculated well in advance for just about any destination on the edge of the solar system though. It certainly will go interstellar but when is another question. At that distance, the bit rate right now is only one kilobit per second, pretty dam good for 4 billion miles away but at 40 billion miles, if it is still transmitting, it would probably be down to 10 bits per second if it could be tracked AND last that long at all.
10. 29 Jan '19 15:141 edit
@sonhouse said
Maybe the one billion dollar price tag has something to do with it. That and the lucky alignment of planets that allowed that journey. I guess though that kind of trajectory can be calculated well in advance for just about any destination on the edge of the solar system though. It certainly will go interstellar but when is another question. At that distance, the bit rate r ...[text shortened]... g, it would probably be down to 10 bits per second if it could be tracked AND last that long at all.
I assume it runs on solar power? So that'll run out eventually.

A billion is chump change for politicians. Maybe we launch 1 per year, aim them at nearby solar systems, and in 100 years or so we will know what's what.

edit: It's called Project Longshot - and if we launched it back in 1975 it would be halfway there by now.
11. sonhouse
Fast and Curious
29 Jan '19 16:37
@wildgrass

It might be chump change for politicians but NASA has a fixed budget. It can't just ask Trump for a 50 billion extra this year, much as they would love to...

I heard on some show that Elon Musk has a proposal for tiny solar sail chips that could reach 20% of the speed of light and launched by the hundreds, chips the size of postage stamps with a small solar sail powered by massive lasers.
So far a pie in the sky thing because the amount of laser power needed would be in the gigawatt region and I don't think that is going to happen any time soon but the concept is valid. Aimed at Alpha Centauri, getting there in about 20 years and then beaming images and such back to Earth which would get here 4 odd years later, say 26 years for the whole thing and we would have closeups of that trinary system, three stars for the price of one. There might even be inhabitable planets around one of those stars. News at 11.
12. 29 Jan '19 18:31
@sonhouse said
@wildgrass

It might be chump change for politicians but NASA has a fixed budget. It can't just ask Trump for a 50 billion extra this year, much as they would love to...

I heard on some show that Elon Musk has a proposal for tiny solar sail chips that could reach 20% of the speed of light and launched by the hundreds, chips the size of postage stamps with a small solar ...[text shortened]... or the price of one. There might even be inhabitable planets around one of those stars. News at 11.
If it was called a "military laser-beam space force" it'd stand a decent chance of funding....
13. sonhouse
Fast and Curious
29 Jan '19 19:58
@wildgrass

THAT would not surprise me a bitðŸ˜‰

Here is the digital response to the 'space force'....... Single digit.