Mercury

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Mercury
Venus Mars Minor Planets. Jupiter		Saturn Uranus Neptune Pluto

DATA

Distance from the SUN	Mean: 57.9 million Km (0.387 au.) Max: 69.7 million Km (0.467 au.) Min: 45.9 Km (0.306 au.)
Sidereal period	87.969 days
Syodic period	115.88 days
Rotation period	58.6461 days
Mean orbital velocity	47.87 Km/sec
Axial inclination	Negligible
Orbital inclnation	7 deg 0.0 min 15 sec
Diameter	Equatorial: 4878 Km
Apparent Diameter from Earth	max : 12 sec .9 min: 4 sec .5
Reciprocal Mass (Sun = 1)	6000000
Density (water =1)	5.44
Mass (Earth = 1)	0.055
Volume (Earth = 1)	0.150
Escape Velocity	4.25 km/sec
Surface gravity (Earth = 1)	0.38
Mean surface temperature	Day: +350°C Night: -183°C
Oblateness	Negligible
Albedo	0.06
Maximum Magnitude	-1.9
Mean Diameter of Sun as seen from Mercury	1 deg 22 min 40 sec

Predicted transites of Mercury accross the Sun

Date	Time of mid transit (UT)
7 May 2003	7h 53m
8 November 2006	21h 42m
9 May 2016	14h 59m
11 November 2019	15h 21m

Description.

Mercury is the innermost of all the planets, and the fastest to go around the Sun. It is the second smallest both in size & mass, the smallest being Pluto. It is virtually without atmosphere. What little atmosphere it does have was probably captured from Solar winds. (The stream of atomic particles thrown out by the Sun.) Mercury has a weak magnetic field of unknown origin. Mercury, seen close up by NASA's Mariner 10 space probe in 1974\1975, resembles that of the Moon. It is heavily cratered by meteorite impacts & has vast lava seas as well as mountainous regions. The surface facing the sun is very hot at about 400°C while the surface not facing the Sun is at -170 °C. This is because there is no atmosphere to circulate the heat around the planet. Mercury rotates on it's axis very slowly, only one & half times for every revolution around the Sun. This means its day is very long, 59 Earth days & its year is very short, 88 Earth days. Its orbit is very eccentric as well so its speed varies greatly. These variations produce some unique effects. As seen from Mercury the Sun would rise in the East, stop, then set in the East. Then it would rise again, move slowly across the sky & set in the West. Then it would rise in the West, stop, then set finally in the West. Mercury has no satellites.