Tuesday, August 30, 2005

"Enceladus Eruptions" CHARM presentation

Today's CHARM talk covered the UVIS results at Enceladus from the flyby last month. I've linked to the PDF file with the slides from the talk above. This talk fit nicely with the press briefing today since it perfectly covered many of the discoveries announced at the talk plus providing more in-depth analysis of the data as well as...more graphs. UVIS detected an atmosphere on ingress of the gamma Orionis occultation in July but failed to detect an atmosphere during the occultation in February. The path of the occultation allowed for measurements at a far southern latitude on ingress, allowing UVIS to measure the patchy atmosphere measured by MAG and INMS. UVIS was able to detect the atmosphere starting at an altitude of 155 km above the surface of Enceladus using the High Speed Photometer (HSP) on UVIS. Compositionally, UVIS found that the atmosphere/plume was made primarily of water vapor with no detection of CO (thus placing an upper limit on CO at 2x1014 cm-2. This is important because INMS detected a species at mass 28 which can either be CO or N2. N2 could be a disassociative product of ammonia in Enceladus' patchy, slushy interior.

In addition to the UVIS data, the talk, by Larry Esposito the UVIS Principle Investigator, also has data from INMS, with a plot of their data from below 500 km. The plot shows a high number of counts from H2O and less amounts from a species at mass 28 as well as hydrogen and maybe methane. The detection at mass 44 is a mix of background noise and CO2. The presentation also has plot from the simulation the CDA team ran to show that their data was consistent with a spread out source near the south pole.

Esposito concludes by stating that the composition of the atmosphere is mostly water vapor with a near surface abundance of 1.5 x 1016 cm-2 with an upper limit on CO at 2% the water vapor density. The atmosphere is not global and has only been found near the south pole. Finally, and here is the kicker as I will go into with more detail later today, "The water vapor escaping from Enceladus is adequate to supply the atomic oxygen in the Saturn system detected by UVIS, and to re-supply Saturn's E ring."

Update 12:45 pm: The detection at mass 44 is a mix of background noise and CO2. Not sure what the mix is, but is less than the detection at mass 28...

2 Comments:

Blogger Bruce Moomaw said...

More news from "The "Independent" ( http://news.independent.co.uk/world/science_technology/article309205.ece ):

(1) "An analysis of its atmosphere revealed it was about 91 per cent water vapour, 3 per cent carbon dioxide, 4 per cent nitrogen or carbon monoxide and about 2 per cent organic molecules."

(2) "Candy Hansen, a NASA scientist working on Cassini's ultraviolet instruments, said that half a ton of material a second was ejected from Enceladus's south pole, which would, over the four billion-year lifetime of the solar system, amount to a loss of 5 per cent of the moon's original mass." Could many of the strange surface features on Enceladus thus be wrinkle ridges?

8/31/2005 03:58:00 PM  
Anonymous Anonymous said...

social security disability
social security adminstration
social security adm
health benefit of pomegranate
pomegranate juice
pomegranate martini
apple benefit cider vinegar
cider michigan mill
apple cider diet vinegar
blakes cider mill
cider mill yates
apple cider press
cider franklin mill
dorian yates
robert yates racing
disability benefit
onion booty
foto graciosas
videostreptease
dibujos de gargolas
carros de bomberos
infected mushroom
magic mushrooms
mushroom
morel mushrooms
mushroom cloud
mushroom head
morel mushroom
mellow mushroom
infected mushrooms
wild mushrooms
magic mushroom
stuffed mushrooms
mushroom kingdom
mushroom identification
mystic lake casino
mystic tan
mystic seaport
bmw salt lake city
jeep salt lake city
mazda salt lake city
ariel little mermaid
princess jasmine wig
elvira wig
wig toupees hair goods
eva gabor wig
cheap costume wig
blonde halloween wig
afghan wig
womens wig
cruella wig
hannah lilly montana wig
monterey bay aquarium
shedd aquarium
lake ozark mo real estate
ariel rebel
wig hairpieces
lace front wig
jessica simpson wig
power rangers mystic force
little mermaid soundtrack
mermaid melody
toyota salt lake city
nissan salt lake city
hannah montana wig
african american wig
blonde wig
marilyn monroe wig
mullet wig
ariel wig
kingston wig standard
betty boop wig
afro wig
medusa wig
lace wig
paula young wig
jack sparrow wig
wilma flintstone wig
strawberry shortcake wig
green loompa oompa wig
tyra banks wig
raquel welch wig
elvis wig
marge simpson wig
dreadlock wig
dolly parton wig
full lace wig
wig and hair piece
drag queen wig
joy luck club
charm deluxe luck
888 joy luck
fleet dynamics
fleet infinite maintenance
newport aquarium
newport news clothing catalog
newport beach plastic surgery
newport cigarette coupon
skoal tobacco
hookah tobacco
us smokeless tobacco
newport cigarette
kool cigarette
clove cigarette
winston cigarette
doral cigarette
marlboro cigarette catalog
newport cigarette coupon
cheap marlboro cigarette
flavored cigarette
monterey aquarium
mystic aquarium
ariel costume
ariel levy
ariel wig
ariel mermaid
ariel ecw
port huron times herald
little mermaid lyric
adult mermaid costume
ariel little mermaid
disney little mermaid
lil mermaid
barrington levy
rose levy beranbaum
trojan condom
trojan zlob
durex condom
magnum condom
flavored condom
lifestyle condom
vibrating condom
kimono condom
jezebelle bond
aladdin bail bonds

8/14/2007 06:19:00 AM  

Post a Comment

<< Home