For several years scientists have been begging to test their theories about Mercury, the closest planet to the Sun. You see, the radar signals come back showing ice exists on the planet, but how could ice exist on a planet so incredibly hot?
NASA sent the spacecraft MESSENGER to orbit the planet and figure the mystery out (among other things). It turns out that ice exists at the planet north and south poles and possibly underneath some “dirt-shielding”.
All of this was uncovered by Professor David Paige, who has previous experience with Mars and the Moon, as he explains in his own words:
“I was able to use the Mercury laser altimeter in conjunction with a three-dimensional ray-tracing thermal model that I built to study ice on the moon, Paige said. “Using these models, I calculated the average temperature on the surface of the planet and concluded that the surface temperatures were too warm to permit the long-term stability of ice. The only possibility was some sort of thin layer of cover that allowed the ice to survive.”
This thin, dark layer is called a regolith and is probably made of organic substances like the Earth’s soil, rich in hydrocarbon compounds that may have come from the comets and meteorites that struck the planet over time. The comets and meteorites may have also contributed the water that seeped under the soil cover to form the icy patches.
MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) is the first spacecraft to orbit Mercury. Its goal is to collect better data about the composition and atmosphere of the planet, and it just completed its first year of information gathering.
While the mix of water and organic compounds on another planet may raise the possibility of extraterrestrial life for some scientists, this is not what excites Paige. For him, the discovery of ice on Mercury is the triumph of science.
“We’re getting a good agreement between models and observations,” Paige said. “What we thought was true is true. The most exciting part of this? We may not know lot of things, but on Mercury we have things under control.”
via UCLA Today