Curiosity Finds Big Iron Meteorite On Mars

NASA’s Curiosity Mars rover took this photo of an iron meteorite called “Lebanon,” similar in shape and luster to iron meteorites found on Mars by the Spirit and Opportunity rovers. The smaller piece in the foreground is called “Lebanon B.” The circles are high resolution views taken with the Remote Micro-Imager. Click to see them. Credit: NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/IAS/MSSS

It’s not the first meteorite found on the Red Planet, but it’s sure the largest. A 6-foot-long (2 meters) iron meteorite named ‘Lebanon’ was spotted by Curiosity’s cameras poking its head out of the Martian soil on May 25th. NASA released the stunning portrait this afternoon.

4.971 kg Sikhote Alin iron meteorite that fell in 1947 in the then Soviet Union. It displays beautiful regmaglypts. Credit: Svend Buhl

With its gunmetal sheen and numerous ‘thumbprints’ it looks identical to many fresh iron meteorites found on Earth. Those Swiss cheese-like holes called regmaglypts form in a couple different ways. Softer, less heat resistant minerals like iron sulfide (troilite) riddle some iron meteorites.

During the plunge through a planet’s atmosphere, the surface of a meteoroid heats up, melts and gets sculpted by powerful, super-heated air. Softer materials melt away or ‘ablate’, giving the meteorite its classic thumbprint texture.

Martian winds and weather could also have eroded out the softer materials to create the cavities. Perhaps both processes were (and still are) at play. The circles are individual,high-resolution photos taken by Curiosity’s Remote Micro-Imager. When you click the image above, you’ll be able to explore the iron’s surface in great detail.

This view of a rock called “Block Island,” the second largest meteorite found on Mars, comes from the panoramic camera on Opportunity. It’s about 26 inches (67 cm) across. Credit: NASA/JPL

This is Curiosity’s first meteorite discovery and the 8th and largest found on the planet. The earlier generation Spirit Rover stumbled onto two potential meteorites – Allan Hills and Zhong Shan – inside Gusev Crater in 2006. They resembled those found by the rover’s twin, Opportunity, which uncovered five confirmed iron meteorites. Here’s Opportunity’s space rock booty to date:

Heat Shield Rock – Found in 2005. Renamed Meridiani Planum meteorite for its location. Type: iron meteorite
* Block Island – 2009 / iron meteorite
* Mackinac Island – 2009 / iron meteorite
Shelter Island – 2009 / iron meteorite
* Oileán Ruaidh – 2010 / iron meteorite

While irons aren’t the most common meteorite – stony meteorites are – they resist erosion better and stand out from the general rocks. That’s probably the reason all those found so far have been metallic.

13 Responses

    1. astrobob

      That is one big iron. Can you imagine what it must weigh and how much is still buried?

        1. astrobob

          Yes, I’m sure asteroid. Who knows – it may be a fragment related to one also found on Earth. For that, you’d need a thorough chemical analysis.

          1. Richard Keen

            Well, that certainly puts my 25-pound Campo (10 pounds on Mars) to shame.
            I wonder what that Big Iron would fetch at the meteorite auction in Denver this fall?

          2. astrobob

            I’ve got a couple Campos, one around 10-pounds. I used to pass that one around but got concerned that someone might create an accidental impact on their toes. So I bought a smaller, less dangerous one and use it all the time in class and at talks.

          3. Richard Keen

            Bob, the biggest Campo I’ve ever seen is in the courtyard in front of a fossil & meteorite shop in Santa Fe. It’s 4900 pounds (Earth weight), about four feet across (a bit smaller than the Mars iron), and is for sale, although I didn’t bother to ask the starting price. There’s no “don’t touch” signs, so I touched it.

          4. astrobob

            That’s huge! Ever seen the photo of Bob Haag with the mother of all Campos? Pity he couldn’t bring it back. It’s probably rusting somewhere in Argentina.

  1. Edward M. Boll

    Mars and Spica still beautiful together. I am still excited about UQ4 but before the end of July, I believe that I will turn my attention to Jacques. With Jacques, more than twice as close to Earth as the Sun in late August, I would not be surprised to see it brighten a tad bit.

    1. astrobob

      I just saw it this morning. A bit of cloud troubled the view, so I couldn’t confirm it in 10x50s, but I brought along my 10″ reflector and it was easy at mag. 6 in a bright sky. Diameter about 3′ and pretty strongly condensed.

    1. astrobob

      Too many! 8 I think. I still have my trusty Edmund 6″f/8 I bought with paper route money when I was 12. My main instruments are the 10″ and 15″ (mostly for rural observing trips) and I often use a small, dedicated refractor for solar observing.

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