February 22, 2013 | 1
Editor’s note: Researchers exploring Mars via rover and satellite have to adapt to the longer day on the Red Planet. Katie Worth, whose Can Earthlings Adapt to the Longer Day on Mars? for Scientific American last month describes the consequences of sleep-pattern changes, is trying it out herself. Follow her experiences in living on “Mars time” at this blog to see how it affects her sleep and behavior. This post is the seventh in a series.
Who could help but be captivated by the videos of last Friday’s meteorite blazing a blistering trail across the Russian sky?
To me, the event serves as a reminder that our planet is a trifling bit of real estate in a busy universe, and we got off easy this time. Just like its inhabitants, the Earth may at any moment be vulnerable to a wrong-place-at-the-wrong-time crisis. If it’s the wrong enough place at the wrong enough time, it will be plowed into by a cosmic cannonball, and the glorious biological achievement that is life on our planet will be erased like one more extraneous scribble on the whiteboard of the universe. In other words, it’s conceivable that everything we ever do will be completely irrelevant.
As I was watching those videos and thinking the gloomily existential thoughts they inspired in me, I was wondering how I could fit them into a blog post about my Mars time experiment, in which I live on a day 40 minutes longer than normal, slowly advancing around earth’s 24 hour clock.
It turns out, the connection between meteors and the length of an Earth day isn’t as farfetched as you may think. Play with this remarkable tool (be warned: it’s easy to kill several hours doing so) developed by earth and space scientists at the University of Arizona and Purdue University, and you will discover that by hurling something large enough at our planet, you can change speed at which Earth rotates by up to several hours. Send a speedy Texas-sized projectile its way at a certain angle and speed and you wind up with a 24 hour 40 minute day, equivalent to that of Mars.
Though it’s within the realm of possibility that a meteor could come along and result in the death of everything on Earth, it’s not really likely that something big enough will come along and dramatically change the Earth’s rotation, so no need to lose sleep over that.. It would take “a really, really big impact” to significantly change the Earth’s rotation, Jay Melosh, professor at Purdue’s Department of Earth and Atmospheric Sciences, told me in an email. “Such an impact has zero possibility of happening in the current solar system.” And even if were to happen, the change in Earth’s rotation would be neither here nor there, since we would all be spending the rest of our days, whatever their length, extinct.
Even without the intervention of cosmic junk, the length of our home planet’s day is not static. I live in Santiago, Chile, where three years ago this week, a deadly 8.8-magnitude earthquake flung most of the nation out of bed at 3:30 A.M., and simultaneously shifted the Earth’s axis by a few inches, thereby shortening our day by about 1.3 millionths of a second, according to earth scientists at NASA. A year later, the 9.0 earthquake in Japan shortened our day again, this time by 1.8 millionths of a second.
Earthquakes aren’t acting alone to speed up our swirl through the firmament: Ocean currents, atmospheric conditions, and melting polar ice caps swallowed into the earth’s equatorial beer belly also contribute.
But while those factors are pressing the planet’s accelerator pedal, something more forceful is slamming on its breaks: The friction of our Moon’s gravitational pull. By some calculations, back in the planet’s primordial infancy, the Earth was rotating at the mad speed of once every six hours. By a couple hundred million years ago, its day was likely about 23 hours long. In another 150 million years, the day may be closer to 25 hours. So perhaps I should stop calling this my “Mars time experiment” and begin calling it my “practicing for AD 150 million experiment.”
And honestly, as time goes on, even the “experiment” part of the title seems a little too lofty a word, and “muddle” seems more accurate. As my bedtime has been slinking toward evening—tonight it will be 4:30 P.M.—I’m struggling against (and sometimes succumbing to) the temptation to stay up later, especially since my current schedule pretty much precludes all social interaction in my geographic time zone. Instead of dragging backward towards a more natural time zone, my circadian clock (or at least my social one) is trying to leap forward into one.
The warning the experts gave me when I started this business, and which I immediately pooh-poohed, was that playing with the length of my day would mess up not just my body clock and my social life but also my cognitive abilities and my mood.
And indeed they have: I have been a professional writer for more than a decade, and consider myself a competent journalist. But writing is hard under the best of circumstances. The late, great David Rakoff described it this way: “Writing is like pulling teeth. From my (privates).” Only he used a different word than privates.
Living on Mars time has not improved those circumstances for me. Writing is a process of making a thousand tiny decisions in a row. On days when I’m more sleep deprived than usual, it takes longer to make each one, and I feel less confident in my decisions. I wrote five separate versions of this blog post, including one that a friend generously described as having “the literary qualities of a Creative Writing 101 paper written by a college freshman on a football scholarship,” before returning to my (more or less) original version, the one I’d written when I was most rested.
Fortunately for me, the most that’s riding on the outcome are a few subpar blog posts. That in itself is enough to inspire anxiety, but I keep reminding myself that in the bigger picture it doesn’t really matter, since one of these days we may all be wiped out by another blistering blaze across the sky.
Previously in this series: