The surface of the Moon consists of iron-rich rocks but the presence of hematite, a form of iron oxide or rust, along the poles in the absence of water and oxygen has surprised scientists. The data reviewed in a Science Advances paper by Shuai Li of the University of Hawaii has studied the facts from Chandrayaan-1's Moon Mineralogy Mapper instrument (M3).
India's Minister of State for Space Dr Jitendra Singh has also acknowledged the revelations which are based on data collected from the nation's first lunar mission Chandrayaan-1 in 2008.
Scientists have suggested a three-pronged model for the formation of rust along the poles taking into consideration previous research suggesting oxygen from Earth’s atmosphere hitches rides to travel to the Moon. With more hematite on the side of the Moon facing Earth, the possibility is that Earth's oxygen could be driving the formation of hematite, according to Li.
The second possibility is hydrogen delivered by solar wind, which prevents oxidation but during certain periods of the Moon's orbit (specifically, whenever it's in the full Moon phase), Earth's magnetotail blocks over 99% of the solar wind. This may provide an occasional window for the formation of rust, as per the scientists.
The paper highlights that water molecules found on the lunar surface may be mixing with iron in the lunar soil and heat from this could increase the oxidation rate; hence there maybe some suitable moments when a rust-inducing chemical reaction may occur.
Third Lunar Mission in 2021
Minister of State for Space Jitendra Singh has revealed that India's third lunar mission Chandrayaan-3 will be launched in early 2021, but without an orbiter. It will only include a lander and a rover.
The orbiter from the second lunar mission Chandrayaan-2 is working fine and has been sending data, claimed ISRO. ISRO had indicated that the third Moon mission will utilise the orbiter already in the lunar orbit. The launch was earlier planned for 2020 but has been delayed due to the outbreak of the pandemic and subsequent lockdown.