But All they Are is Chunks of Ice and Rock

Does it ever seem to you that every time there’s a comet about to appear in our skies, a certain element of what I think of as the Whack Job Brigade (WJB) gets all lathered up and claims (yet again) that whatever it is, it’s NOT a comet!  It’s a space ship. Or a rogue planet.  Or something else they accuse NASA or the U.S. Government or the Trilateral Commission of creating and/or hiding from the rest of us.

The WJB really had a field day with Comet Hale-Bopp back in the 1990s, and the end result was a group of people committing suicide because somebody told them the comet was a “mother ship” coming to save them. From what, is not clear.

Even before that, however, comets were getting a bad rap. In fact, it goes back to early history, when comets were considered bad omens by ancient skygazers. Most of them didn’t go and kill themselves. They just kind of hunkered down until the comet passed and then got back to their daily business of using the stars to foretell the future.

In the 20th century, particularly in the latter couple of decades, we started to see people showing up on Usenet and the early World Wide Web, telling tales of how NASA was hiding the “truth” about comets being spacecraft bearing aliens to help humanity “progress”.  There was (and probably still is) a woman named Nancy, who claimed she was in communication with aliens from the Pleiades or someplace, and they were telling her to tell the rest of us that the upcoming comet, or Planet X, or whatever it was she thought was coming our way, was really here to rescue us. Or something. I could never figure out what her deal was. Other than she honestly claimed that alien voices were in her head. I don’t doubt for one bit that she was hearing voices.  I tangled with her once on Usenet, and she responded by claiming that I was a secret operative.

Yeah. Right.

So, these days, Comet ISON is getting closer to the Sun, and is starting to do what all comets do: sublimate material off as its ices get heated by the warmth of the Sun. The last image I saw showed two tails—one’s a dust tail and the other is a plasma tail. Plasma tails are what I tracked as part of my graduate school work, and so I’m always interested to see how they interact with the solar wind.

And there are several other comets showing up, too. I would imagine the WJB is probably beside itself with frenzied speculation about what all these comets mean. Well, I’m here to tell you. They mean that chunks of ice and rock that formed some 4.5 billion years ago in the outer reaches of the solar system, are on orbits that will take them around the Sun. That’s what comets do when they’re not floating around out in the frozen reaches of the solar system beyond the planet Neptune. And when they get nudged out of their orbits (sometimes by collisions with each other, or gravitational perturbations from nearby planets, or maybe a passing star), they enter into an orbit that will eventually take them by the Sun. And when they get close enough, they do what icy objects always do in the presence of heat: they melt and/or sublimate. Sublimate is a fancy word that describes what dry ice does…and comets have CO2, and many other ices in them, which … ta da… sublimate when they get close to the Sun.

So, while it may be tempting, and perhaps even amusing, to read what the WJB says about comets, I would—if I were you— take what they imagine with a block of salt. Most of them don’t really know what comets are. And they’re missing the boat on how exciting comets can be to observe. There’s really NO need to make comets more exciting by adding aliens, hidden agendas, rogue planets, and all this other nonsense that the members of the WJB want you to believe. The universe, including comets, is far more exciting in its natural state than anything a whack job can dream up.

The big news about Comet ISON right now is that it is due to have its closest approach to the Sun on November 28th.  It might break apart under the gravitational pull of the Sun. Cometary ices are quite brittle, and all other things being equal, they can break apart under the influence of gravity. So, most of the world will wait breathlessly to see if Comet ISON survives. If it does (or even if it doesn’t), there could be quite a show when it (or what’s left of it) appears in the predawn skies in the early part of December.  So, check it out for yourself. Sky & Telescope and Astronomy magazines are sharing great viewing charts, so check it out!  And, participate in a great natural event—the viewing of a comet!

I found a really cool NASA video about sungrazing comets.  Check it out.