‘Mercury's extreme climate turns its poles into an ice making chemistry lab’

WASHINGTON DC: The extreme heat on the planet Mercury likely helps make ice on its polar regions, according to a study which suggests how water could arise, and collect as ice on planets rife with all the necessary components.

The researchers from the Georgia Institute of Technology in the US, said while asteroids may have delivered most of Mercury's water, the planet's extreme daytime heat, combining with its ultracold polar craters -- that never see the sunlight -- could also be acting as an "ice-making chemistry lab".

In their new study, to be published in the journal Astrophysical Journal Letters on Monday, they modelled the complex conditions on Mercury, including solar winds that pelt the planet with charged particles, many of which are key to the ice making chemical process. "This is not some strange, out of left field idea. The basic chemical mechanism has been observed dozens of times in studies since the late 1960s," said Brant Jones, study co-author from the Georgia Institute of Technology.

"But that was on welldefined surfaces. Applying that chemistry to complicated surfaces like those on a planet is groundbreaking research," Jones said.

According to the scientists, minerals in Mercury's surface soil contain what are called hydroxyl groups (OH), which are generated mainly by the subatomic particles protons.

Based on their study, they said extreme heat helps to free up these hydroxyl groups, energise them to smash into each other, and produce water molecules and hydrogen.

The water and hydrogen then lift off from the surface and drift around the planet, the researchers said.

While some of these water molecules are broken down by sunlight or rise far above the planet's surface, others land near Mercury's poles in permanent shadows of craters that shield the ice from the sun, they explained. Since the Solar System's first planet does not have an atmosphere, and thus no air that would conduct heat, the molecules become a part of the permanent glacial ice housed in the shadows, according to the scientists.