New Horizons to flyby Pluto this year

Yes, highly eccentric orbit but it's closest point to the Sun is only just inside the orbit of Neptune, I wouldn't have thought that was close enough for significant sublimation, but I may be wrong. And it's thought that it wasn't formed nearly as far out as it is now (see my #56 above)

The suggestion in the video is that Pluto could have formed as close 15 astronomical units from the Sun. This puts it beyond the current position of Saturn which is orbiting at c. 9.6 astronomical units. Which means that the temperature and gravitational regimes under which it developed were significantly different from Earth's. I'm far from convinced that that the scientists know all the formation mechanisms in this colder, darker and less gravity regime. Hence my suggestion that the structures may be less structurally rigid because they are less dense. It'll be interesting to see what the scientists come up with for an explanation in the end.
 
I'm far from convinced that that the scientists know all the formation mechanisms in this colder, darker and less gravity regime.

As observations of increasing numbers of exoplanets in all sorts of very 'strange' positions that would have been unthinkable two decades ago - such as hot Jupiters, and systems where the planets seem to have totally forgotten about trying to keep to a sensible orbital plane - I would suspect we barely know anything about the formation mechanisms of planets :)
 
You're probably right,Veeb
John Chambers:"the final stages of (planetary)accretion are probably dominated by chance events(Earth and planetary Science Letters,vol.223,pages 241-252)
 
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1985.
The "Rockies" sized mountains are likely water ice. That will not have melted.

Pluto has a 248 year orbit and hence passing closest to the Sun in 1989 (the correct date) is comparatively recently in its orbit. At least this is the implication I meant to give.

Totally agree about the water ice remaining solid, but Pluto has a thin layer of nitrogen, carbon monoxide and methane covering a lot of the surface. New Horizons discovered that Pluto's nitrogen atmosphere was much farther out than expected. This could be due to some nitrogen 'steaming off'. Until the scientists have done their work, we won't really know the cause of this.
 
new techniques for dating the early solar system:dating small 182W* variations in iron meteorites
*tungsten isotope,but i can't do superscripts:D
tungsten istopes seem to be well-mixed in the Solar System(Osmium decay not probable,cosmic ray exposure effects can't be totally ruled out )
radioactive decay of 26Al most likely was the principle heat source for differentiation of early accreted planetary bodies

The interface between active
and dead zones in a protoplanetary disk may mark a transition from laminar behaviour to
turbulent behaviour, which may also affect the manner in which migration occurs , and density gradients at the interfacemay also contribute . Thus, there are several potential mechanisms for
accumulating radially migrating material at specific radii.
(italics mine)
 
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It's fascinating isn't it? It's a clear reminder about how much we don't yet know. Which, after all, is why we explore!

I hope the data still to come will prove sufficient to answer this question?

Incidentally on that latest hi res image it's not the 3000 m mountains that really fascinate me but the apparent huge depression just below them. Hard to tell but it looks like it could swallow several of those mountains whole.
 
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Tonight on BBC R4 they were saying OVER A YEAR to get back all the data. There is a Sky at Night Special on BBC mon 20th July 2015 I think.
 
It's too bad they couldn't have landed mobile explorer like Pathfinder on The surface of Pluto, just to see what the terrain is like. :)
 
We could probably do it now. But horribly expensive.

I think in this case , It might worth the expense. It looks quite different from both the Moon and Mars and other bodies in the system. :)
 
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Perhaps. But likely the USA government prefers spending on other things. New Horizons was cost of about 3 fighter jets. What you'd like might be 100x more at a very rough guess.

Now if the photos show an alien artefact I'd imagine the budget would be found.
 
Perhaps. But likely the USA government prefers spending on other things. New Horizons was cost of about 3 fighter jets. What you'd like might be 100x more at a very rough guess.

Now if the photos show an alien artefact I'd imagine the budget would be found.


That would start a brand new space race. :)
 
Tonight on BBC R4 they were saying OVER A YEAR to get back all the data. There is a Sky at Night Special on BBC mon 20th July 2015 I think.
I6 to 18 months is what I've been reading; I think all the images we've been getting so far have been transmitted compressed, New Horizon still has all the raw images in its memory. And yes I'm looking forward to the sky at Night special.

I think in this case , It might worth the expense. It looks quite different from both the Moon and Mars and other bodied in the system. :)
The problem here is that it has to be travelling incredibly fast to get there in a reasonable time and this is way too fast to be captured into orbit around such a small body. So they'd have to carry a lot of fuel to decelerate and that makes it harder to get it up to those speeds in the first place and so on. It would be massively expensive.
 
It would be massively expensive.
Yes. Absolutely. But certainly possible.
In theory, traversing that distance in a few months is possible, but not for us right now. Perhaps with fission powered ion drive we could do it in a little less than 10 years including deceleration and orbit.
 

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