Featured Research

from universities, journals, and other organizations

Phoebe's Surface Reveals Clues To Its Origin

Date:
June 15, 2004
Source:
NASA/Jet Propulsion Laboratory
Summary:
Images collected during Cassini's close flyby of Saturn's moon, Phoebe, have yielded strong evidence that the tiny object may contain ice-rich material, overlain with a thin layer of darker material perhaps 300 to 500 meters (980 to 1,600 feet) thick.

Images like this one, showing bright wispy streaks thought to be ice revealed by subsidence of crater walls, are leading to the view that Phoebe is an ice-rich body overlain with a thin layer of dark material.
Credit: Image NASA/JPL/Space Science Institute

Images collected during Cassini's close flyby of Saturn's moon, Phoebe, have yielded strong evidence that the tiny object may contain ice-rich material, overlain with a thin layer of darker material perhaps 300 to 500 meters (980 to 1,600 feet) thick.

The surface of Phoebe is also heavily potholed with large and small craters. Images reveal bright streaks in the ramparts of the largest craters, bright rays which emanate from smaller craters, and uninterrupted grooves across the face of the body.

"The imaging team is in hot debate at the moment on the interpretations of our findings," said Dr. Carolyn Porco, Cassini imaging team leader at the Space Science Institute in Boulder, Colo. "Based on our images, some of us are leaning towards the view that has been promoted recently, that Phoebe is probably ice- rich and may be an object originating in the outer solar system, more related to comets and Kuiper Belt objects than to asteroids."

In ascertaining Phoebe's origin, imaging scientists are noting important differences between the surface of Phoebe and that of rocky asteroids which have been seen at comparable resolution. "Asteroids seen up close, like Ida, Mathilde, and Eros, and the small martian satellites do not have the bright 'speckling' associated with the small craters that are seen on Phoebe," said Dr. Peter Thomas, an imaging team member from Cornell University, Ithaca, N.Y.

The landforms observed in the highest resolution images also contain clues to the internal structure of Phoebe. Dr. Alfred McEwen, an imaging team member from the University of Arizona, Tucson, said, "Phoebe is a world of dramatic landforms, with craters everywhere, landslides, and linear structures such as grooves, ridges, and chains of pits. These are clues to the internal properties of Phoebe, which we'll be looking at very closely in order to understand Phoebe's origin and evolution."

"I think these images are showing us an ancient remnant of the bodies that formed over four billion years ago in the outer reaches of the solar system," said Dr. Torrence Johnson, an imaging team member from NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Battered and beat-up as it is, it is still giving us clues to its origin and history."

Phoebe may be an icy interloper from the distant outer solar system which found itself captured by giant Saturn in its earliest, formative years. Final conclusions on Phoebe's origins await a combination of the results on Phoebe's surface structures, mass and composition gathered from all 11 instruments, which collected data during the flyby on June 11, 2004.

"This has been an impressive whirlwind flyby and it's only a curtain raiser on the events about to begin," said Porco.

Cassini arrives in orbit around Saturn on the evening of June 30, 2004 (July 1 Universal Time).

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

For the latest images and information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org. For more information on NASA programs, visit http://www.nasa.gov.


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "Phoebe's Surface Reveals Clues To Its Origin." ScienceDaily. ScienceDaily, 15 June 2004. <www.sciencedaily.com/releases/2004/06/040615081224.htm>.
NASA/Jet Propulsion Laboratory. (2004, June 15). Phoebe's Surface Reveals Clues To Its Origin. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2004/06/040615081224.htm
NASA/Jet Propulsion Laboratory. "Phoebe's Surface Reveals Clues To Its Origin." ScienceDaily. www.sciencedaily.com/releases/2004/06/040615081224.htm (accessed September 2, 2014).

Share This




More Space & Time News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: NASA Captures Solar Flare

Raw: NASA Captures Solar Flare

AP (Sep. 1, 2014) NASA reported the sun emitted a mid-level solar flare, on August 24th. NASA's Solar Dynamics Observatory captured the images of the flare, which erupted on the left side of the sun. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Space Shuttle Discovery's Legacy, 30 Years Later

Space Shuttle Discovery's Legacy, 30 Years Later

Newsy (Aug. 30, 2014) The space shuttle Discovery launched for the very first time 30 years ago. Here's a look back at its legacy. Video provided by Newsy
Powered by NewsLook.com
Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
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:
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