I just got a note about a very cool-sounding event that will be taking place on March 16, 2011. It’s called “A Journey into Outer Space” and presents a slate of names many folks have heard of, talking about their science and the future in space. The event features the BBC’s Professor Brian Cox, who will speak about the Large Hadron Collider and dark matter; Charles Simonyi will describe exactly what it’s like to be aboard the International Space Station; Colin Pillinger (of Beagle 2 fame) will ask if there’s anyone else out there; the inimitable Richard Holmes will chart the history of humanity’s fascination with space; Astronomer Royal Lord Martin Rees will talk about everything Big Bang-related; and Rick Stroud will chair. The event is being put on by a group called IntelligenceSquared.
Now, if you were attending this event in person, there’d be a cover charge — and a pretty reasonable one at that, of only £30.00 for regular admission or £15.00 for students. (About $48.00 USD, or €34.00. Go here to convert that to your local currency.) I think that would be well worth it, if I lived in the area. However, I don’t and so don’t lots of other people. But, the folks at IntelligenceSquared have solved that problem.
For those unable to attend the event in London in person, the organizers have a live stream available, which offers a fantastic interactive alternative for viewerers. Watching live online is free for everybody. You simply have to create a free account with your email and a password, and then enjoy the event. All the details are on their web site, linked above. Note that the time of the event is given in London time, so be sure and figure out what time that will be in YOUR time zone (and remember, some of us go on Daylight Savings Time this next weekend, so don’t forget to take THAT into account, too).
During the event, live-stream viewers will also be able to discuss the questions raised using our comment tool (including Facebook and Twitter), and vote on the motion if it’s a debate. The IntelligenceSquared folk will forward the best comments on Rick Stroud, who will then ask the panellists to answer the questions.
The organizers have a Twitter account and hashtag, so check out their tweets at: #iq2space
Many of the panelists are well known to folks in the blogosphere, and it should be an interesting time. And who knows, you might find yourself asking the Astronomy Royal or Professor Brian Cox (or any of the other panelists) a question of your own.
This image shows the context for orbital observations of exposed rocks that had been buried an estimated 5 kilometers (3 miles) deep on Mars. It covers an area about 560 kilometers (350 miles) across, dominated by the Huygens crater, which is about the size of Wisconsin. The impact that excavated Huygens lifted material from far underground and piled some of it in the crater's rim. At about the 10 o'clock position around the rim of Huygens lies an unnamed crater about 35 kilometers (22 miles) in diameter that has punched into the uplifted rim material and exposed rocks containing carbonate minerals. The minerals were identified by observations with the Compact Reconnaissance Imaging Spectrometer for Mars on NASA's Mars Reconnaissance Orbiter. North is toward the top of this image, which is centered at 14 degrees south latitude, 304.4 degrees west longitude. The image combines topographical information from the Mars Orbiter Laser Altimeter instrument on NASA's Mars Global Surveyor with daytime infrared imaging by the Thermal Emission Imaging System camera on NASA's Mars Odyssey orbiter. Image credit: NASA/JPL-Caltech/Arizona State Univ. Click to enlarge.
I am a long-time Mars junkie. When I was growing up, I used to play at exploring Mars, and I probably expected to be living on the Red Planet some day. Childhood dreams are like that — and the reality they lead to is a far different place.
For example, my “play” Mars looked a lot like Earth. Oh, the sky was red (I figured it had to have a red atmosphere). It had red trees and red monsters and red food. But, it never occurred to me that I wouldn’t be able to stand on its surface and breathe the air. That’s a lesson I had to wait to learn when I grew up and studied the results of ongoing Mars missions. That was when I found out that Mars doesn’t have air like we do here on Earth. it’s got a carbon dioxide (CO2) atmosphere. A thin one, at that. But, scientists suspect that the Red Planet used to have MORE atmosphere.
One of the recurring questions about Mars is the location of all its carbon dioxide. The Red Planet has a cold, thin, carbon-dioxide-rich atmosphere. Liquid water quicky boils away in that environment.
CO2 can get squirreled away in rocks, so-called carbonate minerals or carbonate layers. If they’re underground (under the surface), then that material isn’t easily found — unless you can dig it up and study it.
Essentially, that’s what planetary scientists using the Mars Reconnaissance Orbiter (MRO) have done. Oh, they haven’t used the orbiter to dig underground. They used it as it orbited above the surface to study rocks that have been dug up for us — by cratering events. Such an event was reported on at a meeting of planetary scientists this week.
The target studied was in Huygens crater, a basin 467 kilometers (290 miles) in diameter in the southern highlands of Mar. There are actually two cratering events in the area. When Huygens was dug out by an incoming impactor, that action hoisted material from far underground. Then, the rim of Huygens, containing the earlier lifted material, was drilled into by a smaller, unnamed cratering event.
The occurrence of carbonate in association with the largest impact features suggests that it was buried by a few kilometers (or miles) of younger rocks, possibly including volcanic flows and fragmented material ejected from other, nearby impacts.
So, how does an impact dredge up rocks that show us what Mars was like in the past? When a meteor blasts into the surface of Mars (or any surface), it sends material flying away from the impact zone. That uncovers buried rocks. The MRO has an instrument that can study the chemical makeup of those rocks that have been uncovered.
At several places on Mars where cratering has exposed material from depths of about five kilometers (three miles) or more beneath the surface, MRO’s instrument has found evidence of carbonate minerals. This isn’t the first time carbonates have been found, but the finding does seem to confirm the speculated-on whereabouts of the missing Mars carbon. And, if there are deeply buried carbonate layers are widespread on Mars, that would go a long ways toward explaining what happened to the early Martian atmosphere, whihc was likely a much thicker carbon dioxide layer than we see on the Red Planet today. In essence, the carbon that goes into formation of carbonate minerals can come from atmospheric carbon dioxide.
A dramatic change in atmospheric density remains one of the most intriguing possibilities about early Mars. Increasing evidence for liquid water on the surface of ancient Mars for extended periods continues to suggest that the atmosphere used to be much thicker.
The Technical Low-Down
The observations for this study were made using the high-resolution mode of the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument on the Mars Reconnaissance Orbiter show spectral characteristics of calcium or iron carbonate at this site. Detections of clay minerals in lower-resolution mapping mode by CRISM had prompted closer examination with the spectrometer, and the carbonates are found near the clay minerals. Both types of minerals typically form in wet environments, which raises a number of questions about Mars’s early atmosphere and interactions of that atmosphere with the surface.
