Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

Meteorite Impacts Expose Ice on Mars
NASA ^ | 09/24/2009 | NASA

Posted on 09/25/2009 10:41:29 AM PDT by Dallas59



September 24, 2009: Meteorites recently striking Mars have exposed deposits of frozen water not far below the Martian surface. Pictures of the impact sites taken by NASA's Mars Reconnaissance Orbiter show that frozen water may be available to explorers of the Red Planet at lower latitudes than previously thought.

"This ice is a relic of a more humid climate from perhaps just several thousand years ago," says Shane Byrne of the University of Arizona, Tucson.

Byrne is a member of the team operating the orbiter's High Resolution Imaging Science Experiment, or HiRISE camera, which captured the unprecedented images. Byrne and 17 co-authors report the findings in the Sept. 25 edition of the journal Science.
"We now know we can use new impact sites as places to look for ice in the shallow subsurface," adds Megan Kennedy of Malin Space Science Systems in San Diego, a co-author of the paper and member of the team operating the orbiter's Context Camera.

So far, the camera team has found bright ice exposed at five Martian sites with new craters that range in depth from approximately half a meter to 2.5 meters (1.5 feet to 8 feet). The craters did not exist in earlier images of the same sites. Bright patches darkened in the weeks following initial observations, as freshly exposed ice vaporized into the thin Martian atmosphere.

The finds indicate water-ice occurs beneath Mars' surface halfway between the north pole and the equator, a lower latitude than expected in the dry Martian climate.

During a typical week, the spacecraft's Context Camera returns more than 200 images of Mars that cover a total area greater than California. The camera team examines each image, sometimes finding dark spots that fresh, small craters make in terrain covered with dust. Checking earlier photos of the same areas can confirm a feature is new. In this way, the team has found more than 100 fresh impact sites.

see captionAn image from the camera on Aug. 10, 2008, showed apparent cratering that occurred after an image of the same ground was taken 67 days earlier. The opportunity to study such a fresh impact site prompted a look by the orbiter's higher resolution camera on Sept. 12, 2009, confirming a cluster of small craters.

Right: The patch of ice exposed at this late-2008 crater was large enough for the orbiter's spectrometers to take readings and confirm that it is H2O. [more]

"Something unusual jumped out," Byrne said. "We observed bright material at the bottoms of the craters with a very distinct color. It looked a lot like ice."

The bright material at that site did not cover enough area for a spectrometer instrument on the orbiter to determine its composition. "Was it really ice?" the team wondered. The answer came from another crater with a much larger area of bright material.

"We were excited [when we saw it], so we did a quick-turnaround observation," said co-author Kim Seelos of Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "Everyone thought it was water-ice, but it was important to get the spectrum for confirmation."

Mars Reconnaissance Orbiter Project Scientist Rich Zurek, of NASA's Jet Propulsion Laboratory, Pasadena, Calif., said, "This mission is designed to facilitate coordination and quick response by the science teams. That makes it possible to detect and understand rapidly changing features."


Above: This map shows five locations where fresh impact cratering has excavated water ice from just beneath the surface of Mars (sites 1 through 5) and the Viking Lander 2 landing site (VL2), in the context of color coding to indicate estimated depth to ice.

The ice exposed by fresh impacts suggests that NASA's Viking Lander 2, digging into mid-latitude Mars in 1976, might have struck ice if it had dug only 10 centimeters (4 inches) deeper. The Viking 2 mission, which consisted of an orbiter and a lander, launched in September 1975 and became one of the first two space probes to land successfully on the Martian surface. The Viking 1 and 2 landers characterized the structure and composition of the atmosphere and surface. They also conducted on-the-spot biological tests for life on another planet.


TOPICS: Astronomy; Science
KEYWORDS: astronomy; catastrophism; icepirates; mars; science

1 posted on 09/25/2009 10:41:29 AM PDT by Dallas59
[ Post Reply | Private Reply | View Replies]

To: Dallas59

Thanks for this post. I hadn’t seen this.


2 posted on 09/25/2009 10:47:04 AM PDT by FlingWingFlyer (I don't remember Americans being called "racists" when we fought against Hillarycare.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Dallas59
What's a post about pictures with no pictures?


3 posted on 09/25/2009 11:05:04 AM PDT by Rudder (The Main Stream Media is Our Enemy---get used to it.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Dallas59

Incredible. Thanks for posting this.


4 posted on 09/25/2009 11:10:28 AM PDT by FreeManWhoCan ("By the pricking of my thumbs, something wicked this way comes.")
[ Post Reply | Private Reply | To 1 | View Replies]

To: Dallas59

Possible the oceans are still there but covered with drifting dust?


5 posted on 09/25/2009 11:50:21 AM PDT by UnbelievingScumOnTheOtherSide (Give Them Liberty Or Give Them Death! - IT'S ISLAM, STUPID! - Islam Delenda Est! - Rumble thee forth)
[ Post Reply | Private Reply | To 1 | View Replies]

To: UnbelievingScumOnTheOtherSide

Saw last night on the Science Channel that the water was extremely salty and welled up occasionally due to the interior of Mars still being hot. Of course we won’t really know until we get there...


6 posted on 09/25/2009 11:52:47 AM PDT by Dallas59
[ Post Reply | Private Reply | To 5 | View Replies]

To: 75thOVI; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; Avoiding_Sulla; BBell; ...
 
Catastrophism
 
· join · view topics · view or post blog · bookmark · post new topic · subscribe ·
 

7 posted on 09/25/2009 7:27:07 PM PDT by SunkenCiv (https://secure.freerepublic.com/donate/__Since Jan 3, 2004__Profile updated Monday, January 12, 2009)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Dallas59; SunkenCiv
Saw last night on the Science Channel that the water was extremely salty and welled up occasionally due to the interior of Mars still being hot. Of course we won’t really know until we get there...

That is what you';d expect. Our own oceans became salty at the time of the flood and the flood in all likelihood amounted to the oceans of Mars getting dumped onto this planet. That would also be the basic answer to the question of where Mars' former oceans went.

8 posted on 09/25/2009 8:03:14 PM PDT by wendy1946
[ Post Reply | Private Reply | To 6 | View Replies]

To: Rudder

I can see the Elvis picture in the one on the left. I’m surprised that Hoagland fans haven’t turned up with intricate details of railroad yards and landing sites.


9 posted on 09/26/2009 12:15:11 AM PDT by Kevmo (So America gets what America deserves - the destruction of its Constitution. ~Leo Donofrio, 6/1/09)
[ Post Reply | Private Reply | To 3 | View Replies]

To: wendy1946

http://www.varchive.org/itb/ecocean.htm


10 posted on 09/26/2009 5:31:51 AM PDT by SunkenCiv (https://secure.freerepublic.com/donate/__Since Jan 3, 2004__Profile updated Monday, January 12, 2009)
[ Post Reply | Private Reply | To 8 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson