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| Quick Facts
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Type of Object : Solid Planet
Location : First planet away from Sun
Diameter : 4,878 kilometers (3031.04 miles)
Mass : 3.303^23 kilograms (2.051^26 pounds), or 0.0558 Earths
Temperature : Surface-179°C (354.2°F)
Rotation Period : 58.6462 days
Density : 5.42 gm/cm^3
Distance from Sun : 57.9 million kilometers
Mean orbital velocity: 47.89 kilometers per second
Length of mercurian year: 0.2408 Earth-year, 87.9 Earth-days
Length of mercurian day: 58.6 Earth-days
Rotational period : 58.6462 days
Orbital period : 87.969 days
Mean orbital velocity : 47.88 km/sec
Orbital eccentricity : 0.2056
Tilt of axis : 0.00°
Orbital inclination : 7.004°
Equatorial surface gravity : 2.78 m/sec^2
Equatorial escape velocity : 4.25 km/sec
Magnitude : -1.9 Vo
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| Mercury
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The planet, Mercury, is the closest planet to our Majestic Sun. Itıs about 0.3 astronomical unit away from the sun, approximately 57.9 kilometers.
Itıs like the twin to our moon, with the same diameter and hard rocky surface. Its ancient craters look very much alike to those found on the moon. Most of the craters were caused by the impact of stray meteors that scarred its surface millions of years ago.
If you do not want to age so soon, Mercury is not the place for you. A year on Mercury just flies by. Mercuryıs orbital speed is 29 miles per second-fastest amongst the 9 planets. A year on Mercury is only 88 earth-days. Amazing, huh?
However, on the contrary, 1 mercurian day is 58.6 earthdays long. The reason is its motion. Mercury only makes 3 full spins on its own axis for every 2 orbits around the sun. Thatıs why a day on mercurian world is a little shorter than a year in it. Also due to this perculiar motion, weıll always see the same side of Mercury when its at itıs closest point to our earth.
Thereıs another reason why you should never think of visiting the Mercurian world. Itıs climate is worst than you could have ever imagine! At noontime, temperatures can soar up to 370 Celsius but at night, temperatures can plummet to 185 Celsius. It is like living in a oven for 30 days, then changing for the deep freezer for another 30 days. This phenomenon occurs, as Mercury has no atmosphere to reflect or trap the heat from the sun.
Nevertheless, in 1991, astronomers actually predicted that ice caps may form at the north and south poles of Mercury, in spite of the intensive radiation from the nearby sun. These ice caps could have existed in deep craters, which will constantly keep them in shadows. Therefore, the Sun could not melt the ice.
On earth, Mercury can be seen with naked eye in a clear sky, just before dawn and immediately after dusk. It is a bright star shining just above the horizon. As it is always seen hanging around the sun, hence it was named after the Roman messenger god, which sends the messages of the people to their Sun god.
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| Living on Mercury
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Though no man can ever survive on the planet, but I am still oblige to tell you the living conditions on this hostile planet.
If Mercury ever had an atmosphere, it has long since escaped into space because of the heat of the nearby Sun. There is no air, no water, and nothing can grow on the planet's surface. Astronauts will need strong shielding to protect them from the heat and the Sun's harsh radiation. But bulky spacesuits will feel light because Mercury's surface gravity is only about one-third Earth's.
If you lived on the planet Mercury, the Sun's apparent size would change dramatically.
Mercury is the planet closest to the Sun. But its orbit is fairly elliptical, so its distance from the Sun varies greatly. The Sun looks 50 percent larger when Mercury is closest to the Sun than when its farthest away.
Of course, since Mercury is closer to the Sun than we are, the Sun always looks bigger in Mercury's sky than it does in ours. At its smallest, the Sun looks twice as big from Mercury as it does from Earth. At its biggest, the Sun swells to three times its size in our sky.
From Mercury, the Sun can appear to stand still in the sky - or even move backwards - for the following reason. Mercury's orbit around the Sun is quite lopsided - much more lopsided than Earth's orbit. When Mercury is nearest the Sun, it travels fastest. It travels so fast that its orbital speed outraces its rotational speed. At these times, the Sun appears to stop dead in its tracks - and even for a time to move backwards!
Lastly, the sunlight that strikes Mercury is much more intense than that which warms Earth. As a consequence, temperatures on Mercury can reach a sizzling 800 degrees Fahrenheit during the day. But Mercury spins slowly, so its night is long. And it has hardly any atmosphere to hold in its heat, so at night, the temperature on Mercury plunges to 300 degrees below zero.
Mercury also gets strong doses of deadly ultraviolet energy and X-rays.
Mercury is an incredibly hostile place. Of the eight other planets in our solar system, only Venus is hotter, and only Uranus, Neptune, and Pluto are colder.
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