Mercury

 I’m sure we all remember Mercury from our school days. It’s the closest planet to the sun, traveling around our local star once every 88 days. Now, I learned—way back when—that Mercury was tidally locked to the sun, meaning that one side was always facing the sun, while the opposite side was forever dark. But such is not the case. It turns out that Mercury spins completely around roughly every 59 Earth days. But because it is also moving around the sun, a day/night cycle is about 176 days long. So it has long days, and short years.

It is the smallest planet of our system... except for the dwarf planets. It is slightly larger than Earth’s moon at 9,525.1 miles around its equator. By the way, Mercury has no tilt to it, so it has no seasons except whatever small differences might occur because its orbit is elliptical and not round. The gravity at its surface is roughly 3/8 that of Earth. So a person weighing 100 pounds on Earth would weigh about 37.5 pounds on Mercury.

Like all the ‘inner’ planets, Mercury is a rocky planet. It’s surface is quite cratered, much like our moon.

It is only 39 million miles from the sun. If you were standing on Mercury, the sun would look 3 times larger than it does on Earth. It would also feel 7 times hotter. The daylight temperature can climb to 800 degrees Fahrenheit. At night, that temperature would plummet to -290 degrees Fahrenheit. Therefore, it is not likely that life as we know it would be able to exist there.

That is particularly true because of the atmosphere, what there is of it. It consists of oxygen, sodium, hydrogen, helium and potassium. These are atoms that are thrown up by blasts of the solar winds as well as micrometeor strikes.

The article stated quite bluntly that Mercury has no moons. How lonely it must be. I also wonder, what if it does? In that case, it would need to be very small, or it would have been found by now. But what if there were a pea-sized moon zipping around Mercury? And let’s suppose we eventually sent a manned mission there, to land on the dark side (since the light side is so hot) to bring back Mercury samples. How many spacemen would be killed by that moon zipping through their space suit (and maybe them) before they figured out what was happening? Or would punching through their space suit slow it down enough that it would fall to Mercury’s surface, and they might never figure it out?

Well, I’d have to stop and figure out the physics. And I’m not sure where my physics book is anymore.

 

https://solarsystem.nasa.gov/planets/mercury