Europa's Acid Ice Fields

tr0llb4rt0 writes "The New Scientist reports on recent observations that suggest the ice on Jupiter's moon Europa may be highly acid with a pH of near zero, and have a surface layer of hydrogen peroxide. Two theories have been put forward. One says that the acid has been formed at the surface layer from oceanic salts reacting with the intense radiation from Jupiter, the other that sulphuric acid is coming directly from the ocean, with the water reacting with sulphur produced from undersea volcanos. Wilst reducing the chances of life on Europa, it is not ruling it out completely, as there are terrestrial extremophile bacteria which thrive in highly acid environments."

Comments

Dictionaries rule (www.m-w.com)

[jeblucas]

No.

Main Entry: 1acid
Pronunciation: 'a-s&d
Function: adjective
Etymology: French or Latin; French acide, from Latin acidus, from acEre to be sour -- more at ACET-
2 a : of, relating to, or being an acid; also : having the reactions or characteristics of an acid (acid soil) (an acid solution) b of salts and esters : derived by partial exchange of replaceable hydrogen (acid sodium carbonate NaHCO3) c : containing or involving the use of an acid (as in manufacture) d : marked by or resulting from an abnormally high concentration of acid (acid indigestion)

Volcanoes on Io responsible

[TasosF]

Sulfuric acid found on Europa was reported as far back as 1999 when this article was published on Science@NASA based on this NASA Press release. According to the article, sulfur from volcanoes on Io, another one of Jupiter's satellites, may be responsible for the environment on Europa.

Re:Acid ? pH zero ?

[AJWM]

What scientific illiterate modded this "insightful"?

The pH scale runs from 0 to 14, with a pH of 7 being neutral. The number is actually an inverse exponent and has to do with the concentration of hydrogen ions (H+) in solution. (You could also use pOH, relating to the concentration of hydronium ions (OH-), the relationship is pOH = 14 - pH).

And a monopropellant to boot

[Spamalamadingdong]

I was thinking the same thing. H2O2 is not a particularly powerful (high-impulse) fuel, but if you could refine it you could use it as a source of energy to make something more potent (LH2 and LOX). It would also be a great way of running a self-powered rover/hopper; if it came to a crevasse or other impassable feature, it could use rocket power to jump over it.

This assumes that the concentration is high enough to be recovered and purified using the available local energy. That may not be the case.

Re:H2O2 indicates lots of OXYGEN!

[Walkiry]

It's called Catalase. It's an enzyme that is present in many living organisms and catalyzes the reaction 2H2O2 -> 2H2O + O2 . Plants have it too. In Europa, though, the reaction might be very slow unless there is a catalyst to help it.

So it really depends on how you define "usable", that is, what you really want to do with that oxygen peroxide ;)

Re:Can't have two theories

[devilspgd]

Unless I'm mistaken, you can have two hypotheses which both fit the evidence. In the absence of further evidence, you have two valid theories (although ultimately at least one must be incorrect, or at a minimum incomplete)