This article in The Economist caught my interest for two reasons: “Spiders on Mars” is a cute title; and, second, it is an excellent example of something I rail against all the time; that is, journalistic sensationalism. “Spiders on Mars” is a pretty benign example, but it served to remind me not to fall into the same trap of thinking up blog titles that attract attention rather than representing the content of the blog.
While we, in the northern hemisphere of Earth, are making our way through winter, the southern hemisphere of Mars is reaching the end of Spring. That process results in the blooming of patches of darkness on the surface, carefully monitored by the eyes of orbiting satellites – I have to admit here that I didn’t know we had satellites orbiting Mars monitoring such things! Discovered in the early 2000’s, they are of astrobiological interest, because they indicate local conditions that could be more habitable than Mars’s surface is at other times.
In its winter, the high latitudes of Mars’s southern hemisphere become cold enough that carbon dioxide freezes out of the atmosphere to form a frosty dry-ice icecap roughly a meter thick. As Spring comes, dust trapped within the opaque dry ice warms it from within, turning it translucent. Sunlight reaches the surface under the dry ice to warm it. The base of the dry ice turns back into gas (carbon dioxide). The pressure of the gas, trapped between the surface and its translucent covering, builds up as the ice layer thins. Eventually, the strength of the latter can no longer constrain the former, and the pressurized gas bursts out in little fountains, carrying dark dust with it. The dust settles on the surface of the deflating icecap, forming the dark blooming effect picked up by the satellites. Those small explosions of gas result in radial patterns that look like stylized starbursts. Scientists, with obviously very practical imaginations, called those patterns spiders; hence, “Spiders on Mars”. They added the description of these patterns, calling them “araneiform erosional features”. Again “Spiders on Mars”.
Several things struck me as I was writing this blog: The first was the revelation of satellites orbiting Mars, as I mentioned above; the second was pure speculation – would it be possible to somehow use the process of freezing of carbon dioxide on Mars to take that gas out of our own atmosphere here on earth – in other words to fight our pollution of our own atmosphere; third, perhaps the title of “Spiders on Mars” might be a useful slogan for a system that takes carbon dioxide out of our atmosphere and therefore serves a purpose beyond sensationalism; and fourth, how on earth have we been able to learn so much detail about Mars without ever having been there – I guess I am always amazed at our level of scientific ingenuity in areas few of us ever think about. In a practical sense, we seem to be getting closer and closer to landing, and possibly colonizing, Mars, so this type of detailed information is a necessity rather than just an academic interest. Fascinating, at least to me. The only personal downside it that I probably won’t be around to witness it … but you never know, if Elon Musk has his way!!
I was also encouraged to think that colonization of Mars might be closer than we think by another article in The Economist this week that reported on a major conference held at Lighthaven, near the University of California, Berkley. Lighthaven is dedicated to “hosting events and programs that help people think better and improve humanity’s long-term trajectory”. A recent conference there, entitled “Green Mars” discussed topics like “How to send a billion “Solar Sails” to orbit Mars and send terawatts of warming sunshine onto the surface”. As preposterous as that sounds, the fact that it is even being discussed means it is on the agenda, and the human race seems to have uncanny ability to make scientific dreams, and crazy ideas, into reality in a relatively short time. I can live in hope!
