Two more developments in the scientific search for life off Earth are in the news, and both of them have me thinking about a disturbing fact affecting a lot of people right here on good old terra firma.
One item -- the first direct evidence of lightning occurring on Mars -- was reported today on ScienceDaily, a science news site with about 3 million monthly visitors. More on that number later, but first, the implications of the finding are significant in a number of ways. According to Nilton Renno of the University of Michigan's Department of Atmospheric, Oceanic and Space Sciences, "It [the discovery] affects atmospheric chemistry, habitability and preparations for human exploration. It might even have implications for the origin of life, as suggested by experiments in the 1950s."
Ah, the 50s. Hula Hoops. Father Knows Best. Elvis. Sputnik. Stanley Miller's experiments creating amino acids by passing an electrical current through a mixture of ingredients simulating Earth's early atmosphere. (The current represented lightning. Its effect made soup worth writing about.)
Artist's illustration of a dust storm on Mars. Credit: Brian Grimm and Nilton Renno
The lightning on Mars is dry, meaning there's no accompanying precipitation. It was found via an exhaustive review of data on an "unusual pattern of non-thermal radiation" associated with a violent dust storm that took place on the Martian surface in June 2006. Studies of the strength, duration, and frequency of the radiation, as well as a review of its possible sources, led researchers to conclude the storm was electrically active and produced "huge and sudden electrical discharges," better known as lightning bolts. More on the discovery can be found here.
The other item, reported in ScienceDaily a few weeks ago (and previously published in Nature), announced a new method for detecting extrasolar planets with atmospheres containing spectographic signatures of life. The technique, called transmission spectrum analysis, looks at starlight as it passes through an exoplanet's atmosphere when the planet transits its parent star. The starlight reveals constituent features of the atmosphere, which can then be compared with what is known about Earth's transmission spectrum. Until recently, no one knew what our own planet's transmission spectrum looked like. But that was revealed for the first time when researchers at the Instituto de Astrofisica de Canarias (IAC) analyzed light reflected from the Moon during an August 2008 lunar eclipse. Very clever. And there's more: not only are the spectrographic signatures for Earth-based life now finally understood, they're also obvious (easily detected) because of their inherent qualities. Finding a similar spectrum somewhere in the cosmos will be very big news, indeed. According to Enric Palle of IAC:
"Now we know what the transmission spectrum of a inhabited planet looks like, we have a much better idea of how to find and recognize Earth like planets outside our solar system where life may be thriving. The information in this spectrum shows us that this is a very effective way to gather information about the biological processes that may be taking place on a planet."
All of this is pretty exciting stuff, but I have to admit my enthusiasm has been tempered a bit since stumbling across a very interesting publisher's website I hadn't seen before last night called The Small Science Collective. Affiliated with the School of the Art Institute of Chicago, SSC is about bringing science to non-scientists and dismantling misleading assumptions about the natue of scientific information and who can participate in its dissemination. SSC attempts to do this by encouraging people to think about and communicate science through "cheap and handy one page zines . . . distributed in subways, benches, coffee shops, and any place someone might least expect them." (There's also a 2009 Zine-a-thon contest; Astronomy is this month's theme.)
I enthusiastically applaud this wonderfully creative initiative but spending time on SSC also reminded me that achieving and maintaining scientific literacy remains a serious challenge around the world, and no less so in the United States. How bad is it? Earlier this year the California Academy of Sciences commissioned a national survey by Harris Interactive (sponsor of the often-quoted Harris Poll) to test Americans' scientific knowledge. Among other disappointing findings: only 53% of adults know how long it takes Earth to revolve around the Sun.
I doubt that any of those 53% who are in the dark over the 24/7/365 thing are among the 3 million monthly visitors to ScienceDaily, but I've been surprised way more than a few times since shoving a screwdriver into an electrical socket as a young boy. Even if we assume for a moment that all those monthly ScienceDaily visitors are individual adult Americans (they aren't, of course), that would still represent a small proportion of the U.S. adult population.
Clearly, there's a lot of work to do in the area of science education. Religious literacy is another but complementary topic for development, especially in places where science and religion intersect, critics of religion notwithstanding.
Meanwhile, dust storms are swirling somewhere on Mars. And planets perhaps like our own are passing in silence in front of stars we have yet to discover.
Next stop: Voyagers
Banner bus photo credit: Dorothy Delina Porter
I find this so interesting, it's a lot of information all at once and I have always believed the secret to finding life elsewhere in the Universe has a little bit to do with luck and a lot to do with knowing what to look for.
"Meanwhile, dust storms are swirling somewhere on Mars. And planets perhaps like our own are passing in silence in front of stars we have yet to discover."
I love that line.
Posted by: Laura | July 01, 2009 at 08:14 PM