Liquid water on Vesta!

[Frida Space]

So here you go! Dawn has observed a series of curved gullies on the surface of Vesta which scientists think have been caused by short-lived water flows. The water was probably buried under the ground in the form of ice, maybe brought by collisions with comets. New collisions, however, heated up the ice, melting it and causing the water to flow out of the crater walls and into the crater, depositing a bunch of materials in an alluvial fan. The gullies observed have been formed in the last two million years or so, so relatively very recently, so these processes might still be happening today. Obviously, because the temperature and the surface pressure are so low, the water probably evaporated soon after.

Source: the JPL website isn't loading on my computer at the moment, but whenever it does I'll leave the link here. It was one of the most recent articles, if not the most recent of all.

[Dkmdlb]

Here's from the JPL article:

"Protoplanet Vesta, visited by NASA's Dawn spacecraft from 2011 to 2013, was once thought to be completely dry, incapable of retaining water because of the low temperatures and pressures at its surface. However, a new study shows evidence that Vesta may have had short-lived flows of water-mobilized material on its surface, based on data from Dawn"

Link:

http://www.jpl.nasa.gov/news/news.php?feature=4453

[Frida Space]

"Protoplanet Vesta, visited by NASA's Dawn spacecraft from 2011 to 2013, was once thought to be completely dry, incapable of retaining water because of the low temperatures and pressures at its surface. However, a new study shows evidence that Vesta may have had short-lived flows of water-mobilized material on its surface, based on data from Dawn"

Link: http://www.jpl.nasa.gov/news/news.php?feature=4453

Thanks. That's it.

[Cirocco]

Son of a Kraken... this is why I love space exploration. We're finding more and more (liquid) water evidence everywhere in the solar system. And that is AWESOME!

Man I really hope we'll see a (permanent) space colony on another celestial body within my lifetime.

[michaelsteele3]

All I see is is a bunch of arrows.

But on a serious note, this is pretty cool.

[CptRichardson]

That looks more like sand coming loose from gravity than former water flows...

[Rakaydos]

That looks more like sand coming loose from gravity than former water flows...

I'm no geologist, but....

[NovaSilisko]

That looks more like sand coming loose from gravity than former water flows...

"We're not suggesting that there was a river-like flow of water. We're suggesting a process similar to debris flows, where a small amount of water mobilizes the sandy and rocky particles into a flow," Scully said.

The curved gullies are significantly different from those formed by the flow of purely dry material, scientists said. "These features on Vesta share many characteristics with those formed by debris flows on Earth and Mars," Scully said.

I'm no geologist, but....

Neither am I. So let's perhaps trust the people who are qualified to explain this...

Edited January 22, 2015 by NovaSilisko

[Kulebron]

I've been in mountains, saw these rocky formations everywhere, on ridges 500 meters high, in depressions with very little water flow. Rocks do crack just from uneven heating and cooling under sun. This would be even more unlikely on a planet like this. An earthquake from a big enough meteorite hitting another side of the planet could shake this mass of fine stones, and make it go down. This also could as well be a flow of stones in the very moment of crater formation.

[Accelerando]

I've been in mountains, saw these rocky formations everywhere, on ridges 500 meters high, in depressions with very little water flow. Rocks do crack just from uneven heating and cooling under sun. This would be even more unlikely on a planet like this. An earthquake from a big enough meteorite hitting another side of the planet could shake this mass of fine stones, and make it go down. This also could as well be a flow of stones in the very moment of crater formation.

That's true, but Earth has many times more water in its atmosphere and even in the driest rocks and deserts alone, or these are at least surrounded and affected by atmospheric water on a daily basis, than a dry space rock. Even if the Earthly formations turn out not to be due to the activity of water, "dry" Earth rocks aren't a good example for other worlds.

[Kruleworld]

That looks more like sand coming loose from gravity than former water flows...

Just like the 'flows' (water, but not water) they found on Mars.

[Newt]

AS was mentioned, Vesta is not Earth. Vesta is also not Mars. Vesta, is Vesta, and though some of the process on Vesta are very similar to those we may find elsewhere, some of them have different details, some may have entirely different origins with outwardly similar results. Thus we should be cautious in jumping to conclusions here.

As for this being evidence for liquid water, according to that article, it is not. Rather, they are proposing that there is ice, melted during impacts, which is able to form small gullies in the breif amount of time it has before it boils away in the vacuum.

[lajoswinkler]

This is not liquid water flow, and ESA said that. Let's not spread erroneous informations around.

[notsosmart]

This is not liquid water flow, and ESA said that. Let's not spread erroneous informations around.

Yes but.... NASA said it? do you work for NASA or are you better than any of their scientists? If so, feel free to delete the thread, but if not, I don't see why you should say something like that.

[lajoswinkler]

Yes but.... NASA said it? do you work for NASA or are you better than any of their scientists? If so, feel free to delete the thread, but if not, I don't see why you should say something like that.

No, they did not.

"We're not suggesting that there was a river-like flow of water. We're suggesting a process similar to debris flows, where a small amount of water mobilizes the sandy and rocky particles into a flow," Scully said.

http://www.jpl.nasa.gov/news/news.php?feature=4453

Water (as a substance) would push towards the surface while changing form in the fine particulate matrix of the asteroid. Mostly sublimation and deposition, sometimes possibly liquid while the conditions were right. This matrix has a huge surface area and lots of tiny chambers where you basically have dynamic balance of various phase exchanges. That makes the matrix prone to detaching. Under sufficient gravitational force the material can collapse.

[KerikBalm]

There is often a problem with the terminology used to describe H2O.

To most people, "Water" means *liquid* H2O. In this case, you have Steam/Water/Ice, all for H2O.

But "Ice" is also used to describe other frozen substances, like frozen CO2. Thus they may specify "Water Ice". However, you will often hear about detecting significant quantities of "water" somewhere, but its all in Ice form.

You can't assume that because they say "water" that they mean "liquid water" - not even transiently.

They may mean "water ice" evaporated (or rather, sublimed, ice directly to vapor), and particles that were in the ice then cascaded down the crater.

[Frida Space]

No, they did not.

Water (as a substance) would push towards the surface while changing form in the fine particulate matrix of the asteroid. Mostly sublimation and deposition, sometimes possibly liquid while the conditions were right. This matrix has a huge surface area and lots of tiny chambers where you basically have dynamic balance of various phase exchanges. That makes the matrix prone to detaching. Under sufficient gravitational force the material can collapse.

This is the title of the official paper: "Potential transient liquid water flow features in fresh craters on Vesta" (link). I'm no geologist, and probably neither are you, so let's leave this business to those that do it for a living.

- - - Updated - - -

You can't assume that because they say "water" that they mean "liquid water" - not even transiently.

They may mean "water ice" evaporated (or rather, sublimed, ice directly to vapor), and particles that were in the ice then cascaded down the crater.

No, they actually mean liquid water, not water ice. Read the paper.

Edited January 23, 2015 by Frida Space

[KerikBalm]

I can only see the abstract, not the full paper (btw I am a real scientist, but this is outside of my field).

I know enough examples of bad papers from sources that sound reputable (NASA + Science magazine <- I'm looking at you and that terrible arsenic life paper) to know that I shouldn't just accept something based on an abstract, and one should look at their controls.

But its clear that they mean the flow of liquid was extremely transient.

"Vesta's current surface temperatures and pressures make it an inhospitable environment for liquid water. But, energy from a high velocity impactor that impacts an area of CC could release the mineralogically bound water from the CC and provide temporarily increased temperatures and pressures in the newly formed crater, which would allow liquid water to briefly flow and form the PTFs before it spontaneously boils and evaporates."

Not exactly a candidate for finding life. Transient liquid water from an impact (as already proposed for many martian features) - is actually pretty boring. I don't see why it would be more interesting than the lava lakes on Io, and much less interesting than the hydrocarbon lakes on Titan.

[Frida Space]

I can only see the abstract, not the full paper (btw I am a real scientist, but this is outside of my field).

I know enough examples of bad papers from sources that sound reputable (NASA + Science magazine <- I'm looking at you and that terrible arsenic life paper) to know that I shouldn't just accept something based on an abstract, and one should look at their controls.

Sure, there are a lot of peer-reviewed papers out there which are really bad. I don't know if this is one of them (liquid water on a world like Vesta, even if extremely transient, does sound a bit odd), but what I was saying is that, according to the scientists that did this research, the water was in fact liquid, and not water ice as some people said in this thread.

- - - Updated - - -

No, they actually mean liquid water, not water ice. Read the paper.

As you can see, I used the verb "mean", not "the water is liquid". Sorry for the confusion

[lajoswinkler]

This is the title of the official paper: "Potential transient liquid water flow features in fresh craters on Vesta" (link). I'm no geologist, and probably neither are you, so let's leave this business to those that do it for a living.

- - - Updated - - -

No, they actually mean liquid water, not water ice. Read the paper.

There you go. Do you still have anything to say? Would you like to dispute what real scientists are saying? Maybe you could write a paper too, with all the evidence you gathered.

As I've said, liquid water could appear as very transient, ephemeral phenomena in the regolith and the rocks themselves if the tiny chambers experience optimal pressure and temperature conditions and thus such thing will increase the mobility of the material.

If you think they mean this happened:

Then you're wrong.

Edited January 24, 2015 by Red Iron Crown
Removed some more personal comments.

[Frida Space]

If you think they mean this happened:

Then you're wrong.

Exactly. I never said that. Please don't make things up.

Also, your inability to understand scientific way of writing and blind trust in authority even if it goes against facts is hilarious.

The whole purpose of this thread was to report a new paper, and the paper's title is: "Potential transient liquid water flow features in fresh craters on Vesta". I'm not saying the scientists that did this research are right, but the whole purpose was just to report their discovery, and again, they know much more than me and you.

Edited January 24, 2015 by Frida Space
cleared stuff up

[Red Iron Crown]

Locking this briefly for cleanup.

And we're back.

While healthy debate is encouraged around here, please restrain yourselves from resorting to comments about the character of other posters. Discuss the post, not the poster please. Further personal attacks will be met with more official action.

Edited January 24, 2015 by Red Iron Crown

[Frida Space]

And we're back.

While healthy debate is encouraged around here, please restrain yourselves from resorting to comments about the character of other posters. Discuss the post, not the poster please. Further personal attacks will be met with more official action.

Thank you. Hopefully now we can stop arguing about what the word "liquid" means. :-)