I've Been Thunderstruck

Following up on my post from the other day, where I talked about mirrors left on the moon for earth-based experiments, it seems that’s not the only thing that has been left on the moon through the years of our interaction with it. For example, if you landed in the Sea of Tranquility right now, you’d find:

1. Apollo 11 Lunar Module Descent Stage
2. Neil Armstrong’s Apollo Space Boots, Model A7L
3. Empty Food Bags
4. Tongs
5. Bulk Sample Scoop
6. Camera (Hasselblad El Data)
7. Medals Commemorating Two Dead Cosmonauts
8. Film Magazines
9. Food Assembly, LM (4 man days)
10. Urine collection assembly, large
11. Bag, Emisis
12. Footprint

This is just a small list of the items that are currently on the moon, awaiting pickup by a 21st century garbage truck! I can understand the reason those items needed to be left behind, lest the space capsule weigh too much to escape the moon’s gravity, but it sure seems a shame that we leave junk on the place outside of the earth we visit!

A more complete list of junk on the moon can be at the Lunar Legacy Project.

Last week I wrote about an interesting video I had watched called "Horizon : What On Earth Is Wrong With Gravity?" I learned quite a few interesting things while watching that video, but nothing shocked me as much to find out that there are mirrors on the moon!

When Apollo 11 landed on the moon almost 40 years ago, it was not only the first time we landed on the moon, but it was the start of an experiment that continues to this day. There’s an awesome article about the whole thing from "Science @ NASA," but the crux of the mission is stated as such:

Ringed by footprints, sitting in the moondust, lies a 2-foot wide panel studded with 100 mirrors pointing at Earth: the "lunar laser ranging retroreflector array." Apollo 11 astronauts Buzz Aldrin and Neil Armstrong put it there on July 21, 1969, about an hour before the end of their final moonwalk. Thirty-five years later, it’s the only Apollo science experiment still running.

The mirrors were left of the surface of the moon so we, down on Earth, could shoot lasers at them and help understand the distance between the Earth and the moon in a very precise way.

Here’s how it works: A laser pulse shoots out of a telescope on Earth, crosses the Earth-moon divide, and hits the array. Because the mirrors are "corner-cube reflectors," they send the pulse straight back where it came from. "It’s like hitting a ball into the corner of a squash court," explains Alley. Back on Earth, telescopes intercept the returning pulse–"usually just a single photon," he marvels.

The round-trip travel time pinpoints the moon’s distance with staggering precision: better than a few centimeters out of 385,000 km, typically.

Targeting the mirrors and catching their faint reflections is a challenge, but astronomers have been doing it for 35 years. A key observing site is the McDonald Observatory in Texas where a 0.7 meter telescope regularly pings reflectors in the Sea of Tranquility (Apollo 11), at Fra Mauro (Apollo 14) and Hadley Rille (Apollo 15), and, sometimes, in the Sea of Serenity. There’s a set of mirrors there onboard the parked Soviet Lunokhud 2 moon rover–maybe the coolest-looking robot ever built.

Scientists have learned quite a bit about the Earth-moon relationship in the years that they’ve been hitting it with a laser. Three important points have emerged as a result of the experiements:

1. The moon is spiraling away from Earth at a rate of 3.8 cm per year.
2. The moon probably has a liquid core.
3. The universal force of gravity is very stable. Newton’s gravitational constant G has changed less than 1 part in 100-billion since the laser experiments began.

This is some pretty amazing work, and even more amazing that it’s been going on night after night for almost 40 years! In that time Einstein’s theories have been confirmed, as well as Newton’s Gravitational constant. But, it’s also cast some doubt on other theories, and continued exploration will ultimately flesh out the truth. This is a very interesting article, and I encourage you to read more!

I just spend shy of 50 minutes watching a very interesting BBC show about gravity. Think you know everything there is to know about gravity, just because you understand that it keeps us from flying off the planet, and because you know about Newton? Did you know that time is slower in orbit around the earth than it is on the ground…because of gravity? Did you know that light gets bent over long distances because of gravity? Did you know that both Newton and Einstein were wrong? If you’re interested in science at all, I think you’ll find this quite interesting. There’s even a segment about GPS for all you geocachers out there!

This is a fascinating look at the underground structure of an ant colony. Over 40 tons of dirt was moved by the ants in order to create their living spaces and "fungus gardens." It’s quite amazing when you think about how their size versus the amount of material they are capable of moving. The video is from The Science Channel’s "Ants! : Nature’s Secret Power" broadcast.

Here are five reasons why I’m not rushing out to buy the new Garmin Colorado 400t.

1. No display of nearby caches on mapview. If you’re going after a cache, and watching the map while doing so, you have no idea if other caches are nearby.
2. Unable to mark caches as found. Makes no sense to me, but that’s the case.
3. Unable to edit existing caches. So, if you have a cache in the Colorado 400t that is the first waypoint for a multi-stage cache, there is no way to edit the listing for any additional waypoints. Makes doing puzzle caches and multi’s very difficult.
4. Unable to add a new cache in the field. Must be done through the use of gpx files, so there is no way to create a new cache with coordinates in the field.
5. Too expensive. At $550+, for the level of geocaching features on the unit, I’ll wait until version two.

I’ll be the first to admit there are some way cool features on the Colorado 400t, like the sweet display, the nice topo maps, and the ability to have the unit connect as a data device, enabling drag-and-drop. However, the fact that the unit seems to have taken a few steps back with respect to geocaching functionality makes it a no buy until they improve that very important aspect of the software.