A study published on March 7th in the journal Nature Geoscience reveals the mystery behind the unusual darkness of the planet Mercury.
Mariner 10 was a robotic space probe launched by NASA in 1973 to fly by Mercury and Venus. Since then it is known that Mercury is darker than it should be! But no one exactly knew why. Now, the secret to Mercury’s dark appearance has been uncovered by NASA’s MESSENGER space craft. It took measurements and photographs of Mercury’s surface that revealed that the planet had a graphite-rich crust, which is responsible for its dark surface.
Earlier scientists believed that the iron-rich surface of Mercury makes it appear dark, but the Moon has much more iron than Mercury, yet Mercury is way far darker. It is because cometary micrometeorites striking the planet, left huge deposit of carbon which is known to absorb light and make planet look darker. Using MESSENGER’s data, scientists discovered that carbon’s distribution matches with the location of dark sports across the planet. A mystery that baffled scientists for long is solved now.
For details please check the full paper at: Peplowski et al., Remote sensing evidence for an ancient carbon-bearing crust on Mercury, Nature Geoscience, 07 March 2016
Image: Location of Mercury in sky on Mar 09, 2016 with Venus, Hubble Space Telescope and zodiac Aquarius; Image Source: SkyView AppA study published on March 7th in the journal Nature Geoscience reveals the mystery behind the unusual darkness of the planet Mercury.