Featured Research

from universities, journals, and other organizations

Oxygen detected in atmosphere of Saturn's moon Dione: Discovery could mean ingredients for life are abundant on icy space bodies

Date:
March 2, 2012
Source:
DOE/Los Alamos National Laboratory
Summary:
An international research team has discovered molecular oxygen ions (O2+) in the upper-most atmosphere of Dione, one of the 62 known moons orbiting the ringed planet. The research was made possible via instruments aboard NASA's Cassini spacecraft.

False-color image of Saturn's moon Dione, imaged by the Cassini spacecraft in 2005.
Credit: NASA/JPL/Space Science Institute

Los Alamos National Laboratory scientists and an international research team have announced discovery of molecular oxygen ions (O2+) in the upper-most atmosphere of Dione, one of the 62 known moons orbiting the ringed planet. The research appeared recently in Geophysical Research Letters and was made possible via instruments aboard NASA's Cassini spacecraft, which was launched in 1997.

Dione -- discovered in 1684 by astronomer Giovanni Cassini (after whom the spacecraft was named) -- orbits Saturn at roughly the same distance as our own moon orbits Earth. The tiny moon is a mere 700 miles wide and appears to be a thick, pockmarked layer of water ice surrounding a smaller rock core. As it orbits Saturn every 2.7 days, Dione is bombarded by charged particles (ions) emanating from Saturn's very strong magnetosphere. These ions slam into the surface of Dione, displacing molecular oxygen ions into Dione's thin atmosphere through a process called sputtering.

Molecular oxygen ions are then stripped from Dione's exosphere by Saturn's strong magnetosphere.

A sensor aboard the Cassini spacecraft called the Cassini Plasma Spectrometer (CAPS) detected the oxygen ions in Dione's wake during a flyby of the moon in 2010. Los Alamos researchers Robert Tokar and Michelle Thomsen noted the presence of the oxygen ions.

"The concentration of oxygen in Dione's atmosphere is roughly similar to what you would find in Earth's atmosphere at an altitude of about 300 miles," Tokar said. "It's not enough to sustain life, but -- together with similar observations of other moons around Saturn and Jupiter -- these are definitive examples of a process by which a lot of oxygen can be produced in icy celestial bodies that are bombarded by charged particles or photons from the Sun or whatever light source happens to be nearby."

Perhaps even more exciting is the possibility that on a moon with subsurface water, such as Jupiter's moon Europa, molecular oxygen could combine with carbon in subsurface lakes to form the building blocks of life. Future missions to Europa could help unravel questions about that moon's habitability.

Two sensors aboard Cassini built by Los Alamos National Laboratory are expected to come into play beginning later this month, and again in April and May, when the Cassini spacecraft flies by the moon Enceladus. The moon is one of the brightest objects in our solar system, reflecting back nearly all of the sunlight that strikes it, thanks to a shimmering surface of snowy ice crystals. The moon also unleashes plumes ofmaterial from its south polar region. Los Alamos' ion-beam spectrometer and ion-mass spectrometer may help answer key questions about the composition of these plumes.


Story Source:

The above story is based on materials provided by DOE/Los Alamos National Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. L. Tokar, R. E. Johnson, M. F. Thomsen, E. C. Sittler, A. J. Coates, R. J. Wilson, F. J. Crary, D. T. Young, G. H. Jones. Detection of exospheric O2+ at Saturn's moon Dione. Geophysical Research Letters, 2012; 39 (3) DOI: 10.1029/2011GL050452

Cite This Page:

DOE/Los Alamos National Laboratory. "Oxygen detected in atmosphere of Saturn's moon Dione: Discovery could mean ingredients for life are abundant on icy space bodies." ScienceDaily. ScienceDaily, 2 March 2012. <www.sciencedaily.com/releases/2012/03/120302210234.htm>.
DOE/Los Alamos National Laboratory. (2012, March 2). Oxygen detected in atmosphere of Saturn's moon Dione: Discovery could mean ingredients for life are abundant on icy space bodies. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2012/03/120302210234.htm
DOE/Los Alamos National Laboratory. "Oxygen detected in atmosphere of Saturn's moon Dione: Discovery could mean ingredients for life are abundant on icy space bodies." ScienceDaily. www.sciencedaily.com/releases/2012/03/120302210234.htm (accessed April 18, 2014).

Share This



More Space & Time News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth's Near-Twin Found Orbiting Red Dwarf

Earth's Near-Twin Found Orbiting Red Dwarf

Newsy (Apr. 17, 2014) The newly-discovered planet is roughly the size of Earth and could have liquid water on its surface. Video provided by Newsy
Powered by NewsLook.com
New Baby Moon 'Peggy' Spotted In Saturn's Rings

New Baby Moon 'Peggy' Spotted In Saturn's Rings

Newsy (Apr. 15, 2014) A bump in the rings could be a half-mile-wide miniature moon. It was found by accident in Cassini probe images. Video provided by Newsy
Powered by NewsLook.com
Americas Glimpse Total Lunar Eclipse

Americas Glimpse Total Lunar Eclipse

AFP (Apr. 15, 2014) A total lunar eclipse, the first since December 2011, took place early Tuesday morning with the Americas getting the best glimpse. Duration: 1:19 Video provided by AFP
Powered by NewsLook.com
NASA Showcases Lunar Eclipse

NASA Showcases Lunar Eclipse

AP (Apr. 15, 2014) Star gazers in parts of North and South America got a rare treat early Tuesday morning - a total eclipse of the moon. (April 15) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Cassini Detects Hint of Fresh Air at Dione

Mar. 2, 2012 NASA's Cassini spacecraft has "sniffed" molecular oxygen ions around Saturn's icy moon Dione for the first time, confirming the presence of a very tenuous atmosphere. The oxygen ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins