Do you want the good news or bad news first? OK, the bad news. Remember when we learned last week that Curiosity had made a “history changing” discovery in a Martian soil sample? Many of us speculated that the rover had detected the first organic, carbon-containing compounds on Mars.
Well, it turns out it was just a big misunderstanding between the MPR reporter and Mars Science Laboratory (MSL) project scientist John Grotzinger. During the original interview, Grotzinger explained to reporter Joe Palca that Curiosity had analyzed the first soil sample in its Sample Analysis at Mars instrument. While SAM can detect organics, Grotzinger’s reference to the discovery being “one for the history books” was actually a reference to the entire Mars mission, not a specific finding.
Somehow the NPR reporter misinterpreted the excitement surrounding the first soil analysis with Grotzinger’s description of the mission as history-making. Each thought the other was talking about a different thing. Indeed at the time of the interview, the first sample had only begun to be analyzed, so NASA scientists wouldn’t have even known the details of its chemical contents. Results, described as “interesting” rather than earth-shaking, will be presented next week at a meeting of the American Geophysical Union in San Francisco. More on the topic HERE.
Since it’s still very early in the mission, we shouldn’t be too bothered if some sort of Holy Grail moment has yet to happen. Look at what Curiosity’s found so far – an ancient stream bed filled with water-rounded cobbles, layered buttes of sedimentary rock like a postcard from the Grand Canyon and a most amazing assortment of wind-sculpted rocks. And don’t forget – we got there in the first place and Curiosity couldn’t be healthier.
Does anyone doubt that handfuls of history-making discoveries lie ahead? My only frustration is that NASA didn’t attempt to correct the misunderstanding sooner through one of its many press releases.
Now for the good news. Mercury, a planet with a surface temperature hot enough to melt lead has been confirmed by MESSENGER probe to have ice deposits in its polar regions. What the heck? Given that it’s the closest planet to the sun, you’d think it an unlikely place for ice, but the little planet’s axis is tipped less than one degree, so areas around its poles are never exposed to sunlight. Since Mercury has no substantial atmosphere to capture and distribute heat, its surface temperature ranges from 800 degrees F in sunlight to 200 below in the polar regions.
While radio-bright areas likely due to ice have been detected from Earth by the giant Arecibo radio telescope in Puerto Rico as long ago as 1991, new data from NASA’s orbiting MESSENGER spacecraft confirm that water ice is indeed present both exposed on the surface as well as buried beneath dark, tar-like deposits.
The probe uses neutron spectroscopy to measure hydrogen concentrations within Mercury’s radar-bright regions. Based on the amount of hydrogen seen, scientists can estimate the volume of water ice present, because water, or H2O, is two parts hydrogen.
“The new data indicate the water ice in Mercury’s polar regions, if spread over an area the size of Washington, D.C., would be more than 2 miles thick,” said David Lawrence, a MESSENGER participating scientist.
The dark material could be a mix of organic compounds delivered by carbon-rich comets and asteroids several billion years ago during the solar system’s youth. Astronomers believe that Earth was similarly enriched by water and organics. I like the connection, and I like that polar opposites – excuse the pun – find a home together on a most unlikely planet. To read more about the discovery, click HERE.