Stellar Apocalypse Shows Water

Andy_Howell writes "Astronomers using the SWAS satellite found a cloud of water vapor around the aging giant star CW Leonis, and the most plausible explanation is that the star incresed in lumiosty during its giant phase and is boiling away its comets. This is the first evidence for water in another solar system. In five billion years, our sun is expected to do the same thing."

Comments

Re:Alternative theories?

[JetJaguar]

If you're talking about stellar atmospheres, then yes, astronomers assume that all the oxygen gets bound up in carbon, unless you're talking about S type stars (low carbon abundance stars) then the oxygen gets bound up in metal-oxides and you start seeing strange things like zirconium-oxide or titanium-oxide.

However, outside of a stellar atmosphere, you can easily form other molecules containing oxygen, and since hydrogen is the most abundant element, water is going to be formed in reasonably large quantities.

As for dying stars being able to melt comets when their main sequence progenitors could not... This is not a surprising result. When a star enters the red giant phase, the outer layers of the star may cool off, but the luminosity (the power output) of the star goes way up (think Betelgeuse). Even if the outer portion of the star is cooler, it's still going to be warm enough to melt ice!

Finally, I'm not sure what the big deal about all this is anyway. Astronomers have been observing H2O masers around red giants and star forming regions for years. We've known for a long time that water is out there...

So . . .

[SimplyCosmic]

. . . What you're saying is that should some company out there attempt to patent the process of using a dying star to produce water, we have evidence of prior art, right?

Re:Incredible discovery

[RobertFisher]

It's a pretty sad day for /. moderation when a clueless post such as this gets moderated up to "4, insightful".

It is actually very remarkable that molecules exist in space at all. Why? There are two sides to the process -- creation and destruction.

(*) Creation : Interstellar space is in general very tenuous , and so the likelihood that any two atoms combine in the gaseous phase to form a molecule is very improbable.

(*) Destruction - Once a molecule is created, it doesn't live forever. Space is a very harsh environment, and any molecules created are subjected to harsh cosmic radiation, the stellar radiation field (resulting from all stars surrounding it), as well as stellar winds and shocks. Any of these processes is cabable of disrupting molecules.

When you go ahead and do the naive estimate for the abundance of a molecule balancing creation and destruction rates, assuming only gaseous phase processes, you find that it is highly unlikely to find any substantial amounts of molecules in interstellar space. Indeed, when astronomers first invented instruments capable of detecting rotational mode transitions of molecules like CO and H_2O in interstellar space, their theoretician colleagues told them to forget the plan.

The reason why we have clouds of molecular gas in our galaxy today is a rather amazing one which no one originally anticipated. Besides gas, there are also small, solid dust grains belched out from winds from cool red giant stars in their final phases of evolution. Atoms collide and freeze out onto the surfaces of these grains, where they can remain for a very long time, migrating very slowly along the surface via Brownian processes. Every once in a while, it will bump into another or molecule frozen out in a similar fashion, thereby creating a more complex molecule. The dust grains catalyze the generation of molecules -- without them, we wouldn't have such an abundance of molecular gas in the galaxy today. Indeed, astronomers believe star formation in the early universe was substantially different from that which occurs today because such dust grains would have been completely absent.

I think this result is particularly surprising since one might expect that any winds or shocks thrown off by a star capable of boiling away a comet might also tend to powerful enough to destroy the molecules generated. If that really is the mechanism involved, it is a remarkable coincidence that the winds are just powerful enough to ablate the comets, but not so powerful as to destroy the molecules present.

Bob

Snooty bottled water of the future

[Ukab the Great]

"Try perrier, drawn from pristine dying solar systems"

Water, Beer, etc.

[Alien54]

I recall that a while back there was a discovery of cosmic clouds of what was basically alchohol in space, spanning satires based on star trek with spock as the designated driver.

there was this Slash Story on how the compounds for life are all over space.

Farscape is starting to look reasonable.

Check out the Vinny the Vampire comic strip

Suicide Watch?

[Copperhead]

Do we need to put Hemos on a suicide watch? First the article on the Milky Way colliding with Andromeda, and now this story, both with references to the sun boiling away in 5 billion years, I'm wondering if he's slipped into some Woody Allen type depression.

Move than just proving water

[Meatlog]

We're already fully aware of water having either existed on other planets in the past or existing now as in the case of the moons of Jupiter. Life can sustain in wildly different environments, not just temperate grasslands.

but what about indoor swimming pools?

[layingMantis]

Several billion years from now, the Sun will become a giant star and its power output will increase five thousand fold. And the press has blatantly ignored this issue and instead concentrates on scandal and violence! I'm no scientist but this could have significant consequences on global warming.