Mercury, the closest planet to the Sun, surely has no frozen water, right? Guess again: Solar winds form ice

Mercury, the innermost planet in the Solar System, reaches searing temperatures. Yet ice still manages to exist on its rocky surface. How? The heat from our star actually contributes to the formation of ice, according to a paper published in The Astrophysical Journal Letters on Monday. Mercury’s surface can get up to 400 …

[Pascal Monett]

Interesting process

One major point that makes this whole thing possible is the lack of atmosphere. If Mercury was massive enough to hold an atmosphere, no ice would be possible because the atmosphere itself would be hundreds of degrees.

But I guess it's only Jupiter-sized planets that can hold an atmosphere when the orbit is that close to a star. Any rocky planet that close will have the solar wind strip it bare in a few million years (a galactic blink of an eye).

[Anonymous Coward]

Re: Interesting process

Given that the length of a day on Mercury is 176 Earth days, I'm not sure that the atmosphere would be that hot. At least not uniformly, and almost definitely not at night.

[SkippyBing]

Re: Interesting process

I think the convection currents would ensure the atmosphere was continuously mixing with cold air from the night side dragged into the light by the rapidly rising hot air.

[Brewster's Angle Grinder]

A loud place

"...convection currents..."

SORRY, WHAT DID YOU SAY? YOU'LL HAVE TO SPEAK UP. I COULDN'T HEAR YOU OVER THE SOUND OF THE HURRICANE-FORCE WINDS.

[Muscleguy]

Re: Interesting process

Except such tidal slowing will not have been in operation at the start of Mercury's formation. It is still too close to Sol to have retained an atmosphere.

And as we see with Mars and its atmosphere, gravity alone is not enough. You also need a decent enough magnetic field to stop the solar wind stripping your atmosphere over time. Which is what happened to Mars which is far enough from Sol that it retains a very thin atmosphere.

The idea that we can terraform the Martian atmosphere by bringing in material from the asteroid belt falls on this rock. Anything we add will just get eroded away so we will have to keep adding stuff to Mars' atmosphere until Sol goes red giant.

[SkippyBing]

Re: Interesting process

Honestly if we get to the stage we can terraform Mars I'd expect rigging up a magnetic field wouldn't be a problem.

[Brewster's Angle Grinder]

Re: Interesting process

I reckon we put in a new moon. We could "borrow" one of the dwarf planets. If we got it in close enough it would stir up Mars' interior and, given a few millions years, get the magnetic field humming again.

And, much like the Earth/Moon system, our new Mars/moon system would orbit its barycentre. So, if we plum for the obvious choice, we'd have Ceres in parallel with Mars.

_{Sorry. That was a helluva lot of set up for a really lame joke.}

[Palpy]

Re: Interesting process... with iron...

One of the hot Jupiter exoplanets (WASP-76b) has been shown to have iron vapor in the atmosphere. Like Mercury, it's tidally locked to its star, so on the dayside the temp runs around 2400 deg C. Strong winds appear to carry the vapor from the dayside into the night, where the temperature drops to around 1400 deg C, cool enough for the iron vapor to condense into droplets and rain out.

Science daily link: https://www.sciencedaily.com/releases/2020/03/200311121832.htm

[jake]

Re: Interesting process... with iron...

Wot, no ElReg link? Heathen!

https://www.theregister.co.uk/2020/03/11/wasp76b_molten_iron_rain/

[Blackjack]

So there is ice and fog in Mercury?

Sailor Mercury (From Sailor Moon) ended being scientifically correct?

[Anonymous Coward]

Re: So there is ice and fog in Mercury?

Just have to sort out Pluto now...

[Anonymous Coward]

Re: So there is ice and fog in Mercury?

Already sorted. Pluto definitely has ice (a lot of it). However, there is no water in the atmosphere so no fog.

[bombastic bob]

Re: So there is ice and fog in Mercury?

I would expect there to be a lot of heavier elements on Mercury, too - rare earths and gold and platinum and uranium and other such things, in higher concentrations than Earth. Proximity to the sun - outer planets are less rocky, inner planets more rocky. I expect the "rockiest" one to be Mercury.

The nights are long - you could land on the dark side and conduct mining operations during the night, when it's cold instead of roasting [easier to heat people and things than to cool them]. And apparently there'd be water there as well [like on the moon I guess].

I think the planet mercury in Japanese is 'Suisei' - 'liquid star', best understanding. So the Sailor Mercury reference to water, etc..

[TheProf]

What I took from the video

If you want to keep ice on Mercury you have to stick it where the Sun don't shine.

[David 132]

Re: What I took from the video

All the way to the 7th planet? Seems a long way to go for some ice.

[The Oncoming Scorn]

Re: What I took from the video

https://www.youtube.com/watch?v=0XIncbNbIP0

[Woza]

When hell

Freezes over?

[roytrubshaw]

Re: When hell

<Pedant>According to Dante, hell *is* frozen; at the centre anyway.</Pedant>

[jake]

Re: When hell

Fortunately, today's boffins don't have to take instruction from early 14th century allegory, despite the best efforts of many pig-ignorant Western politicians.

(Apologies to any pigs who may be reading this. It's just an expression, no offense intended.)

[Anonymous Coward]

Re: When hell

OINK!!

[bombastic bob]

Re: When hell

"You've frozen EVERYTHING! Do you have any idea how long it takes to get the pilot lit?"

(from an Animaniacs cartoon - they went to hell, yeah - and froze it over)

[JulieM]

Temperatures can soar over 400C

Temperatures can soar over 400C, and yet somebody will inevitably moan that they are too cold.

(Coat? I don't need no stinkin' coat! It's double figures out!)

[phuzz]

Re: Temperatures can soar over 400C

It's always in double-figures outside if you measure in Kelvin.

[The Nazz]

Re: Temperatures can soar over 400C

"always double figures in Kelvin?"

Except when it's triple figures? Which is quite often.

Also, -10deg C is double figures. No coat yet here in tough West Yorkshire.

[Muscleguy]

Re: Temperatures can soar over 400C

When going for a run in the great outdoors anything over 5C and I'm in shorts. I will wear a jacket (breathable) for rain up to 10C but the chances of getting exposure above 10C (while generating lots of personal heat) are very much less.

I also grew up running in Auckland, NZ and therefore learned both a tolerance of being VERY wet while running and enjoying running in the rain (it temporarily helped with the humidity and was cooling).

So no coat above 10C, fine. If I'm running.

[Anonymous Coward]

Re: Temperatures can soar over 400C

We Muricans don't use Frenchie's numbers.

[jake]

Re: Temperatures can soar over 400C

Celsius was Swedish, not French.

[W.S.Gosset]

Re: Temperatures can soar over 400C

Sorry jake, HildyJ's correct. The scale we use was created by a Frenchman. Jean-Pierre Christin.

The scale Celsius created was identically centigrade but inverted: water boiled at 0° and froze at 100°.

[jake]

Re: Temperatures can soar over 400C

By that logic, the first person to turn over an hourglass invented a new thing.

[W.S.Gosset]

Re: Temperatures can soar over 400C

Well-lllll.... the chap who picked up the hourglass and observed that it made more sense for time to run forwards than backwards, so maybe the numbers being jotted down should go up over time rather than down, certainly has developed something markedly more sane and useful and contributory than the first.

[jake]

Re: Temperatures can soar over 400C

I guess it's a good thing that scientists world-wide have decided to call the scale "Christin", then, as they should know.

[W.S.Gosset]

Re: Temperatures can soar over 400C

M. Christin would be far from the first and far from the last person to have his/her contribution written out of the science paradigm by Tha Boyz. :) E.g., the chap who discovered that arteries work precisely the opposite way round from "medical science"'s understanding, not only did not get the Nobel Prize for it, but the 2 chaps who excitedly asked to help him out on some subsequent work DID. I was there at the Royal Institution when its head did the scientific community version of tearing the Nobel Committee a new arsehole for this. Very publicly with the lights on him, cameras rolling, going internationally. Didn't work -- the committee is as answerable as ICANN. There is more arbitrariness and bitchiness in "science" than you can poke a pointed stick at.

Having said that, "Celsius" works better as a scale-name than Christin. I reckon. ;)

[aks]

Re: Temperatures can soar over 400C

Remind me again where Farenheit was from. Germany, wasn't it?

[Michael Wojcik]

Re: Temperatures can soar over 400C

He was from Not-France. Freedom temperature scale!

(Actually, the Farenheit scale makes some sense; its standard points, 32 and 96, are separated by a power of two so thermometers could be graduated by successive subdivision. Centigrade's usefulness is primarily in its connection to the rest of SI, and that came along much later.)

[Annihilator]

Closest

"Mercury, the closest planet to the Sun"

Mercury is also, currently, the closest planet to Earth. Strangely, on average it's the closest planet to Earth (about 45% of the time) with the rest of the time split between Mars and Venus.

It's also (on average again), the closest planet to all other planets in the solar system, which still blows my mind.

[Michael Wojcik]

Disappointed

No comments about making water, or about the solar winds of Uranus? What are we, a bunch of adults?

[Lotaresco]

Re: Disappointed

OK, if you insist. I found out when camping that making water on a hot rock isn't a good idea. It's the smell it causes that is the problem.

[bombastic bob]

"Making Water"

couldn't help myself...

/me gives thumbs-up for interesting article on the way out - coat, please