2006-11-12 09:59:59 · 5 answers · asked by victimofthekillers 1 in Science & Mathematics ➔ Astronomy & Space
mercury has a day that last 58 of our days, so the same side is away from the sun for very long periods of time. the same way that the earth gets cold at night and warmer during the day, the same thing happens to mercury, escept that each night last for the equivalent of 29 of our days (on average). the fact the mercury has negligible atmosphere greatly exacerbates this effect
2006-11-12 10:10:29 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Mainly because there is no atmosphere to retain heat. Mercury is about the size of our moon, with similar gravity.
It's also interesting that Mercury's day is two-thirds the length of its year, about 58 and 88 earth days respectively. This is an example of gravitational resonance that happens to smaller bodies after a long time of being in the vicinity of larger bodies. Our moon's 'day' is now equal to its 'year' around earth (28 days), which is why we always see the same side of it (and the 'dark side' is not the same as the 'far side' - just ask George Lucas or Gary Larson).
2006-11-12 10:18:07 · answer #2 · answered by hznfrst 6 · 0⤊ 0⤋
Mercury has no atmosphere to retain heat, the radiant heat is disbursed in a v-shaped pattern when it hits the planet, so the side not facing the sun cannot recieve heat. If it had an atmosphere to speak of, the heat would be trapped in atmospheric gasses and therefore cover the entire planet, but, thats just not the case
2006-11-12 10:10:48 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Mercury has no atmosphere, therefore there's no way for heat from its sunlit side to migrate around to the dark side. Also, once the sunlit side is heated and then rotates into darkness there's no atmosphere to retain that heat.
2006-11-12 10:03:08 · answer #4 · answered by Chug-a-Lug 7 · 0⤊ 0⤋
It's also the furthest distance from the influence of the suns heating.
2006-11-12 10:08:51 · answer #5 · answered by The Garage Dude 4 · 0⤊ 0⤋