Rev 61 Enceladus (March 12 2008) Options

[jasedm]

I'm ashamed in the presence of you chemists.

[Juramike]

space.com article on Enceladus is out: http://www.space.com/scienceastronomy/0803...yby-update.html

-Mike

[volcanopele]

For those who missed the press briefing:

http://www.jpl.nasa.gov/news/cassini20080326.cfm

[Juramike]

Emily's article regarding today's briefing on Enceladus: http://planetary.org/news/2008/0326_Cassin...tes_Like_a.html

Nicely written, Emily!

-Mike

[nprev]

You got that right, Mike. Superb work, Emily, written in such a way that even a humble artificial intelligence such as myself can understand it all!

The cometary compositional similarity is interesting. Almost begs the question of whether something unexpected (heating) happened to them rather then something funny about Enceladus. I can't see any possibility of Enceladus being a captured body.

[Holder of the Tw...]

I would dearly love to see some 10m resolution (or better!) NAC photos of the hottest areas of those tiger stripes, along with the WAC context shots. I know they plan some high resolution views in the next flyby, but I haven't yet read just how high the resolution will be. Hope their plans for the next flyby work. The 15 year night cometh soon.

[CosmicRocker]

Can one of you astrobiololgy or icy body chemical types comment? I read the headlines noting the discovery of "complex organics," but the published spectrograph displays the heaviest broad peak centering around 40 Daltons. I wouldn't normally describe molecules of this weight range as "complex."

Are molecules heavier than the C2/CN/CO range typically considered complex by space scientists?

I noted that Emily's blog entry stated that "At higher masses, not shown on the graph above, "we saw more complex compounds, like propyne, propane, maybe even acetonitrile, and then we saw things even more complex. But they were so weak in signal that we didn't venture an identification." Propane and propyne should have appeared on that graph, since its X-axis goes up to 50 Daltons. Was that data simply erased from the publically released spectrograph?

[JRehling]

The cometary compositional similarity is interesting. Almost begs the question of whether something unexpected (heating) happened to them rather then something funny about Enceladus. I can't see any possibility of Enceladus being a captured body.

Yeah, is what we're seeing between comets and Enceladus anything but ices + one-time heating to drive a little chemistry? It doesn't look to me any more remarkable than the fact that SiO2 exists in the rocks of Earth, Moon, and Mars or that N2 exists in the atmospheres of Venus, Earth, and Mars. You put the same elements together, and you usually get the same compounds.

[DFortes]

Yeah, is what we're seeing between comets and Enceladus anything but ices + one-time heating to drive a little chemistry? It doesn't look to me any more remarkable than the fact that SiO2 exists in the rocks of Earth, Moon, and Mars or that N2 exists in the atmospheres of Venus, Earth, and Mars. You put the same elements together, and you usually get the same compounds.

Exactly - thankyou.

My view is that the 'comet' label - whether it was meant to or not - connotes some suggestion that the organics are primordial. However, the heat flux and plume activity strongly suggest active chemical synthesis (a la Matson), which (to my feeble mind) is more astrobiologically interesting.

[nprev]

I would dearly love to see some 10m resolution (or better!) NAC photos of the hottest areas of those tiger stripes...

My thoughts exactly. I strongly suspect that the emission areas are very localized, extremely narrow, and MUCH warmer than their immediate surroundings, which are presumably experiencing secondary heating... the actual vents have temps certainly exceeding 273 deg K.

[ugordan]

... the actual vents have temps certainly exceeding 273 deg K.

Ummm... I'm sorry, I don't understand that. How much is that in Fahrenheits? That's obviously the only allowed scale, given yesterday's news conference...

On a more serious note, a question for John Spencer: Is the new highest temperature the average over the sensor footprint, or was it extrapolated to the actual width of the tiger stripes (so the average temperature is actually lower than stated in the press release)?

[ElkGroveDan]

How much is that in Fahrenheits?

One of the fun things about Google is that you can convert anything to anything else. Type in 273K in F. and it will come back 31.7. If you are using the Google browser tool bar you don't even have to hit enter. The drop-down suggestion will give you the answer without leaving the page you are on.

Its amazing how many odd units they take into account. Try 40 furlongs in nautical miles. 10 Hands in decimeters. 50,000 milliseconds in fortnights. Warning: you could waste a lot of time on this.

[Juramike]

One of the fun things about Google is that you can convert anything to anything else. Type in 273K in F. and it will come back 31.7. If you are using the Google browser tool bar you don't even have to hit enter. The drop-down suggestion will give you the answer without leaving the page you are on.

Its amazing how many odd units they take into account. Try 40 furlongs in nautical miles. 10 Hands in decimeters. 50,000 milliseconds in fortnights. Warning: you could waste a lot of time on this.

My favorite is that Google Earth can measure distances in Smoots.

The irony that Oliver Smoot was head of American National Standards Institute (ANSI) and the president of of the International Organization for Standardization (ISO) is beautiful.


[/off-topic witicism]

[ugordan]

I was being sarcastic up there, but I'm glad - this Google tip is awesome! That's much faster than googling for "fahrenheit to celsius converter" or such.
Thanks, EGD!

[djellison]

tWarning: you could waste a lot of time on this.

100 (meters per hour) = 515 090.655 smoots per year

55 mph = 242 hands per second

(500 million miles) per (6 months) = 167 316.677 feet per second

240 000 (square feet) = 7 698.81934 sq smoots

This is important stuff!!