On Thursday, it was announced by NASA that water ice has been found on Mercury based on new evidence. Sean Solomon, the principal investigator for the Mercury Messenger program, said in the announcement that the probe found new evidence that deposits found in shadowed regions of the poles on Mercury is actually water ice. Messenger found that the ice is typically in impact craters.
There was a press release from NASA that said the tilt of the rotational axis of Mercury is almost at zero, which is less than one degree. This means that there are hidden pockets at the poles of the planet that never experience sunlight. Decades ago, scientists made claims that there was water ice at the poles of Mercury, but this new evidence provides ‘compelling support’ for those claims. The water ice was discovered by neutron spectroscopy to measure the average hydrogen concentrations by Messenger.
“The neutron data indicate that Mercury’s radar-bright polar deposits contain, on average, a hydrogen-rich layer more than tens of centimeters thick beneath a surficial layer 10 to 20 centimeters thick that is less rich in hydrogen,” wrote David Lawrence, a Messenger scientist based at the Johns Hopkins University Applied Physics Laboratory. “The buried layer has a hydrogen content consistent with nearly pure water ice.”
Messenger was launched in August of 2004 and it made three flybys of Mercury in 2008 and 2009 before it actually entered into the orbit of the planet in March of 2011. There are over 100,000 images that Messenger took of Mercury that can be seen on the website of NASA.