The Red Planet continues to surprise us! This week NASA's Mars Reconnaissance Orbiter (MRO) discovered an unexplained hole on the surface of Mars. In a photograph taken by the unmanned spacecraft an unusually big hole can be clearly seen, and it’s left astronomers scratching their heads.
[Image Source: NNASA/JPL-Caltech/Univ. of Arizona]
As our closest planetary neighbor, we do know a lot about Mars. The MRO has been on the Red Planet's orbit pattern for 11 years and its images are constantly being analyzed by a team at NASA. While the surface of Mars is covered in various holes, hills and depressions, this particular pit really stands out.
Mars regularly takes beatings from meteorite impacts which leave significant craters. It also suffers from pits created by collapsing lava tubes and massive voids carved out by ancient floods on the planet's surface. The MRO monitors lots of well-known holes for changes due to volcanic activity and earlier this year it discovered this intriguing shallow depression that caused some excitement over at NASA HQ. However, this new pit really has them stumped. It’s summer in Mars' south pole which means the sun is low enough to really highlight the planet's surface by accentuating the shadows caused by the changes in topography. In the photo of the pit, we can see a glint of light that is likely to be ice at its base.
Around the mysterious dent are clear patches of frozen carbon dioxide. The Swiss Cheese effect is thought to occur when the dry ice has refined into gas under the summer sun.
The hole was captured using the MRO's High-Resolution Imaging Science Experiment, or HiRISE camera. This lets researchers observe objects on Mars that are bigger than one metre in size from about 300 kilometres away.
Putting that into perspective it means this hole is hundreds of metres across. Check out NASA's website for a hi-res version of the image.
Scientists are asking the question about how this dent was formed. Is it a collapse of the surface or is it a remnant from a type of impact? Without further investigation, the questions will remain unanswered but no doubt NASA has a team working around the clock to get the answers.
The MRO has been sending back high-resolution images of the red planet since March 2006. The collected imagery has informed us of a planet surface that is occupied by dust tornadoes and mysteriously messaged sand dunes. It has even spotted a bit of space junk strewn across its sands. Images of the failed Mars Probe were spotted on Mars confirming the probes last miserable moments. An unknown computer glitched caused the probe to only fire its rocket engines for 3 seconds instead of 30, leading to the rocket plummeting to its demise.
The orbiter is going above and beyond its original mission after it completed its primary goals by 2008! No doubt there will be more exciting holes discovered by the MRO before its retirement.