MESSENGER Spacecraft on Death Watch

Hey Space Placers!

Been getting caught up with family the last couple of days after returning to the US.

NASA's highly successful MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft is on a death watch that is expected to conclude sometime on April 24th, 2015, when the spacecraft slams into the far side of Mercury at almost 9,000 mph.

Artist's View of MESSENGER over Mercury
Credits: NASA/JHU APL/Carnegie Institution of Washington

The biggest finding to me from MESSENGER is the fact that abundant water exists at the poles of Mercury in permanently shadowed regions (PSR's). PSRs are places in the solar system - our Moon has them at the poles - where sunlight has never reached. This has allowed for the deposit of water from countless asteroid and comet impacts, both of which contain lots of water, to accumulate in these frigid areas.

Mercury has enough water in its polar PSR's to cover an area the size of the state of Washington to a depth of two miles! That, is a LOT of water.

One other thing that I think MESSENGER has given us is POSSIBLY the ability to classify meteorites that may originate from there. We have 1 or 2 POSSIBLE rocks from space that MAY have similarities to Mercury. 

MESSENGER was able to map the chemical/geological make up of the surface of the planet closest to the Sun. This could potentially allow the chemical makeup of a meteorite to be compared to that of Mercury. We have done this before with the match up of a whole class of meteorites to the asteroid Vesta.

Finding a space rock from Mercury would be way cool as we have never returned samples from the planet, nor any other planet. We have returned samples from the Moon, an asteroid and comet (dust grains from the coma/tail).

Next week is a BIG week for NASA due to the demise of MESSENGER and the 25th anniversary of Hubble Space Telescope (HST)....stay tuned for more coverage of these events.

Sky Guy in VA