Come on in, the Water is…Frozen

MESSENGER detected the presence of polar ice on Mercury. The spots shown in yellow are craters containing ice. Source: Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory

Water – the source of all life. It’s been found on what we have believed for many moons to be that little hot-tempered planet named Mercury. It seems the celestial body has a shady side, a split personality perhaps; one side ferociously hot, while its polar opposite features some craters of ice. NASA scientists have unequivocally confirmed the presence of water on the planet. Ready for a swim? Ice-skating may be more appropriate.

The Finding

Rarely does consensus on discoveries such as this occur. Three methods, neutron spectrometry, near-infrared reflectance and thermal models from MESSENGER, were used to conclude and confirm the presence of water and organic material on Mercury.

The duality of Mercury is somewhat perplexing; can you imagine living on a planet with a temperature range between -223C and 427C? It is in these shaded, cold regions, those that never see the sun, where the ice lies bare and exposed. However, data from MESSENGER also show that frozen water is found in slightly warmer areas. It lies buried beneath a dark material, an insulator of some sort covering it, and there’s a lot of it. Estimates put the amount of water ice on Mercury between 100 billion and 1 trillion metric tons. That’s enough water to cover an area the size of Washington, D.C., 3.2 kilometers deep.

Where Did the Water Come From?

Much the way Earth came to have water and organic material, it is thought that comet impacts and asteroid strikes created the same organic building blocks of life on Mercury. At last Thursday’s news conference, researchers were bouncing around all sorts of hypotheses on what this discovery could mean for life in other parts of our solar system. Messenger principal investigator Sean Solomon, of Columbia University’s Lamont-Doherty Earth Observatory said “there’s a lot of water out there, as there is a lot of water around other stars, but at substantial distance. “The solar system is “a soggy place ” according to Jim Green, director of NASA’s Planetary Science Division. Green went on to explain his enthusiasm with that statement, indicating “it really bodes well for us to continue on the exploration, following the water and its signs throughout the solar system.” How water was brought to Earth and Mercury, were probably brought to other planets.

With any good find, come more questions…

These observations, while extraordinary, can only heighten our curiosity about Mercury and the rest of the galaxy. Is the dark material in the polar craters on Mercury mainly organic compounds? If so, what sorts of chemical reactions has that organic material undergone? Is this the same material that gave rise to life on our planet? Are there regions on Mercury that have both liquid water and organic compounds? Only by continued exploration of space can we hope to find answers to these questions.

Life as we know it, will probably not be found on Mercury given its ultra-thin atmosphere and proximity to the sun. The discovery of water ice and dark organic material can still inform the hunt for organisms beyond Earth and help scientists piece together the puzzle of how life began on our planet. We still do not fully understand the beginnings of life and the chemical reactions associated with those beginnings on our own planet.

Last week’s discovery of water and organic material on Mercury will indicate we have a lot to learn. Hopefully, it opens up vast areas of research that radiate outward, showing the connections of our segmented universe. How we see view and study other planets has great value for how we analyze and safeguard ours. For instance, what are the implications for planetary warming (climate change)? What can the ice trapped beneath the organic carbon material tell us? The thermostat of astrobiology has just been ratcheted up a notch.