Tiny Moons

When I was in the eighth grade, I wrote a paper for science class about the moons which orbit other planets in our solar system. The year was 1973, just prior to the very first encounter with Jupiter by Pioneer 10 in November of 1973. Little to nothing was known about these natural satellites which tag along with most of the planets in our solar system. So it was a rather short essay that I turned in to my science teacher.

But I was pleased with my summary of all the latest facts about moons. The size, mass, orbital characteristics, and albedo (brightness) had been determined for most of the satellites that were known at the time. Rotation information was known for a few. But nothing was known of their surface features, internal composition, atmospheres, or magnetic and radioactive characteristics. The only telescope photos - of the largest or closest ones - were mere fuzzy blobs. So my challenge was to somehow make these dry, boring numbers, and those blurry dots in black and white, into an interesting overview of a subject which seemed largely ignored in both the classroom and the press.

My solution was to focus on the oddities, rather than the statistics. For example, it was known that the two moons of Mars had irregular shapes, like potatoes. And Neptune's moon Triton orbits retrograde (backwards compared to its host planet's rotation.) These were mysteries that seemed to promise amazing discoveries to come. I delved into recent issues of Science News magazine and dug up as many fun facts as I could find. Although I got an A on that paper, the true reward has been a lifelong interest and fascination with the solar system's impressive collection of moons and satellites.

The summer passed, and ninth grade began for me. And Pioneer 10 approached Jupiter. While everyone oohed and aahed over the gas giant's stripes and red spot, I was immensely gratified to see the first ever close-up of Ganymede:

Ganymede

This blurry portrait was a nice follow up to my science essay. It made me feel lucky to be alive to witness the discoveries ahead. And indeed, the discoveries have been pouring in ever since. We now know that Io has active volcanoes, Enceladus has gigantic geysers, and Europa may harbor an ocean beneath its icy surface. We have learned that small moons shape the rings of Saturn, and even braid portions of the ring material as they play tag with one another. We have discovered many more moons around the outer planets, and even micro moons around asteroids. In recent months, it was announced that, in addition to the Earth's well-known moon, we have also had a tiny, temporary, tag-a-long moon for the past couple hundred years, locked into an oddly shaped, not-quite orbit in our immediate vicinity.

I will go into more detail about these discoveries, and many other topics about cosmology, space exploration, astronomy, SETI, and the speculative insights of science fiction in my forthcoming articles for the Space Dabbler blog. I am not a scientist, just an enthusiastic fan of space exploration. As with my eighth grade science paper, I will hold back on the dry statistics and math, to focus on the interesting wonders and on what it all means. Occasionally I will rant about how I think space exploration should be done, as I critique NASA and other institutions, or point out flaws in sci-fi shows and popular thinking. And as was the case before Pioneer 10, let's always keep in mind that we have no idea what's out there waiting to be discovered. But so far, every blurry blob has turned out to be its own unique and bizarre little world. So, even if you don't think I should get an A for my blog, let's at least give our universe an A for Amazing!