Quick Links
Home
Mercury Main
Location and Orbit
Topography
Physical Structure
Missions to Mercury
References & Links
Quiz
|
 |
The Messenger
A station like the herald Mercury
New-lighted on a heaven-kissing hill...
-- William Shakespeare (Hamlet, Act III) |
Named by the Romans after their fleet-footed and crafty messenger god, Mercury lives up to its namesake in more ways than one. The planet possesses a swift, eccentric rotation that, throught the ages, has fooled astronomers into thinking that it is a comet, a star, or even two different planets. The closest planet to the Sun, Mercury comes at times within 46 million kilometers of it, exposing itself to a temperature exceeding 477 degrees Celsius. Yet radio telescopes on Earth have suggested that ice may exist on this planet whose surface temperature is beyond the melting points of many metals. As a consequence of this close solar proximity, astronomers know less about Mercury than they do about other planets farther away from Earth. Even to date there has been only one scientific mission to study Mercury, the Mariner 10, which circled the planet three times in the 1970's. The information garnered from the Mariner expedition has created more questions, which have now gone unanswered for decades. This may soon change with the projected launch of the Mercury Messenger, a surface probe scheduled to launch in 2004. Until further research comes in, however, this quickly turning and mysterious planet will remain so relatively close and yet so tantalizingly far.
Quick Facts
Average Distance from the Sun5.79 x 107 km
SizeMass: 3.30 x 1024 kg
Diameter: 4,878 km
Density: 5,427 kg/m3
Rotation and OrbitRotation about Axis: 58.6 Days
Period of Revolution about Sun: 0.24 years (87.6 Days)
Orbital Inclination: 7.0o
Orbital Eccentricity: 0.21
Temperature-180o to 430oC
Number of Satellites (Moons)none
|
Quick Links
Location and Orbit
Topography
Physical Structure
Missions to Mercury
References & Links
Quiz
|
|