In our solar system, Mercury is the smallest planet and the closest to the Sun. It held many secrets and was considered an enigmatic planet for long. Its secrets had been unravelled by a NASA probe called Messenger. Its four years long study ended on April 30, 2015 when it crashed on the far side of Mercury at a speed of more than 8,750 miles per hour (3.91 kilometers per second).
Certain facts about Mercury:
- Its day-time temperature is 430oC.
- At night it plunges to minus1800C.
- The dark craters at poles which always face away from the Sun are permanently in a frozen condition.
- Though this planet has a huge, iron-dominated core that takes up three-fourths of the planet’s diameter and half its volume, the rocks and dust on Mercury’s surface contain very little iron.
- The planet’s surface is very dark and reflects only about 7% of the sunlight.
- One of the reasons could be that Mercury gets dumped on by a lot of material derived from comets, researcher Syal notes in a press release from Brown University.
- The comet-borne carbon would actually stick around, in the form of tiny particle clusters called agglutinates, which act like a stealth darkening.