Category Archives: astronomy

Mars on Earth

Preparing for the Red Planet

Some years ago I wrote a popular fulldome show about Mars called MarsQuest.  In it, we discuss future missions to Mars, and ask the question, “Where on Earth can we go to learn about Mars?”

Research station at Devon Island, Nunavut, Canada. Courtesy Mars Institute.
Research station at Devon Island, Nunavut, Canada. Courtesy Mars Institute.

As it turns out, there are several good Mars-analog regions here on Earth where scientists have trained rovers and practiced for crewed missions to the Red Planet. One is called the Haughton-Mars Project, run by the Mars Institute, in cooperation with the SETI Institute, NASA, and the Canadian Space Agency in northern Canada for several years. One look at this desolate landscape, and you’d swear it’s Mars.

Several robotic explorers have been tested at the site, and a number of researchers have studied the surface conditions at the site to understand how they might be similar to those found on Mars, particularly at the polar regions.

Mars-like conditions can also be found in Antarctica, particularly in dry valleys that might not be too different from similar terrain on the Red Planet.  In addition, the deserts in Utah also provide useable regions to understand conditions on Mars.

Some years ago, when I was in graduate school, groups of us went to Hawai’i to study volcanic features similar to those found on Mars, as well as other terrain called sapping valleys. Tramping around the slopes of Mauna Loa and Kileaua gave us a good feeling for the volcanic terrains on Mars.

You might ask, why go through all this work if people won’t be going to Mars for some time yet?  It may well be decades before we send people to Mars, but that doesn’t mean we can’t at least prepare and train in areas that are similar to the planet. Things will be alien enough there, and any kind of training will give future Mars explorers a leg up once they get to the planet. It’s also a great way to learn more about the alien landscapes that our own planet sometimes hands us.

Such studies are a legacy that we can hand down to the folks who WILL be going to Mars someday. They aren’t us, at least not unless we get a human-to-Mars program going in the next few years. No, they’ll be our kids, or maybe even our grandkids. And, all the work we do today will not be wasted on them.

Comets Get Such Interesting Press

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.