Exploring The Solar System: Mercury

Mercury

Does this place look familiar? “Ah,” you say, “It looks like the Moon. The first astronauts set foot there in 1969.”

Yep, it does resemble the Moon, somewhat. But, this is Mercury — named after the Roman god of travel and business. LIke its namesake, it does get around — but is limited to orbiting around the Sun once every 88 days. At its closest, Mercury is only 46 million kilometers from the Sun (that’s 28.5 million miles for those of you who are resisting assimilation into the metric collective). Compare that to the Earth (and Moon) — we orbit the Sun at an average distance of 149 million kilometers (93 million miles). As you might imagine, being so close to the Sun, Mercury can get pretty darned hot. In full sunlight, temperatures there top out at 426 Celsius (800F). At the poles (where the Sun doesn’t ever shine on Mercury) the temps are -203C (-333F).

I recently read a book called “Higher Than Everest” (available from Cambridge University Press and Amazon). In it, the author describes an “extreme expedition” to Mercury to do some cliff hiking — and he makes it sound like an entirely do-able kind of field trip.

Could humans make this kind of journey? Sure, given the right equipment and time to do it right. Before you ever left Earth, however, you’d need to get plenty prepared. Along with physical conditioning, you’d study maps of the planet, getting to know the cratered surface from old Mariner 10 images. Then, you’d need to get there, using a heavily-shielded spacecraft. After that, you’d need something to get you to the surface safely, and of course a protective suit to keep you cool and safe from the radiation environment once you stepped outside. The good news is that since Mercury’s gravitational pull is much less than Earth’s, you’d weigh a lot less than you would on Earth, even with the survival suit. The hike itself would be about like walking across rough terrain on Earth — lots of rocks and boulder fields. Climbing would be a bit more difficult just due to your bulky space suit. And, you’d need to be a lot more careful than you ever would on an Earth hike. But it could be quite the adventure!

Wanna look for Mercury this year? Your best bets in 2002 are to look to the western horizon immediately after sunset (never look directly at the Sun!) around May 4 and September 1st. If you’re an early riser, look along the eastern horizon immediately before sunrise during around June 21st and October 13th this year. It won’t be an easy sight to see, but it’s worth trying. Just remember to be careful and protect your eyes!