grouperlab

A nice day for a drive, back from Indianapolis to Lafayette for an improvisational outreach event, to be recorded at the planetarium of the local high school.  I can enjoy the weather, and the quiet to think and reflect, but there are a lot more trucks on a Tuesday …

Most Mondays and Tuesdays (and Wednesdays, as well) are busy campus days this academic year, between lab meetings with grad students and faculty responsibilities (such as advisor to the professional society student chapter).  “Spring Break” isn’t really a vacation time for faculty; it’s when we get other work done that is hard to squeeze in among the undergrads and grad students.  But with great weather and a promise to take care of myself, it’s time sleep in, attend to items around the home, and drive around to finish some chores before the last big push.  Monday, it was garden care and grocery shopping; Tuesday, it was checking on the preparations for the Indianapolis Motor Speedway event. 

I got back from the National Space Grant meeting late on Saturday, March 2, so I have had several opportunities to notice billboards during my drives around Indiana.  Why is this important?  We have billboards all the time.  There are billboards everywhere.  The lawyer billboards in Indianapolis and Lebanon are not that much different than the lawyer billboards in Houston and Galveston.  Fast food and local restaurants.  But wait, what’s that one?

“Total Solar Eclipse, in 28 days.  This message brought to you by…”

A curious opportunity for one of the billboard advertising agencies, cycled in among the electronic display ads that have become more popular.  So, I’m not the only one counting down.  The billboard is a reminder as well.  And of course, the electronic ones can even get down to hours and minutes, like they did last month for “The Big Game”.   (I will probably be too consumed with event minutiae to notice at that point… no, I will notice that too.  That’s what singular focus does for me.). And instead of it simply being lost revenue, the agency can claim the time spent (whether or not they had sold other ads) as something more generous, more beneficial, more altruistic.  A Public Service Announcement.

I guess that is what I have been doing with a lot of my time lately.  It’s not quite the self-promotion that it may seem, although there is always the insistence by the videographer.  “My name is Barrett Caldwell, and I’m an Engineering professor at Purdue.”   Yes, it’s my face, and my voice, but the topic isn’t about my research (I’m not an astronomer or planetary scientist, after all).  In fact, although I do them and put passion and effort and craft into them, I still have mixed feelings about the self-promotion aspect of some video interviews and photo shoots.  So, why is this different, even as it has become more frequent over the past few weeks?  Because I’m doing engagement and inspiration about the Total Solar Eclipse.  A wonderful and special event, coming to our homes and back yards and favorite places.  A mystical and spiritual experience, connecting us across generations and cultures of humanity, expressing wonder at this celestial dance.  Whether you’re telling the stories of creatures eating the sun, or drawing the filaments of the corona, you’re describing a moment where the world literally goes from bright day to strange shadows to sunset and back in a matter of a couple of hours.  And when will we experience it again here?  

This gives us a chance to think about the size of our neighborhoods and what counts as close.  If I mean “here” to talk about central Indiana, total eclipses occur on a time period best measured in human lifetimes.  (The last totality visible in Bloomington was the year of Purdue’s founding, in 1869.  Nowhere in Indiana gets another show before 2099.). Even if we talk about “here” as the current “lower 48” US states, the time scale is decades – not until 2044.  (See, we were just lucky to be able to be within a day’s drive twice since 2017.). Somewhere on Earth, we can get a solar eclipse every few years (but, like October 2023, the moon may be too far away, or not quite aligned well enough, to actually get a total eclipse of any duration).  But, in some of my outreach talks, I have been struck by another element of awe: Earth has the best eclipses!  Think about it, from the perspective of “here” being our planet.  Mercury and Venus have no moons.  No eclipses for you!  Jupiter, Saturn, and beyond have lots of moons, but the Sun isn’t a big disk in the sky.  You can’t even stand on the surface of a gas giant and point.  The Mars rover Perseverance was able to capture solar eclipses on Mars in 2022.  The shadow of Deimos could be mistaken for a sunspot, or when we see (through a telescope with special filters) a transit of Venus across the much larger disk of the Sun.  Even Phobos, the much larger Martian moon, is irregularly shaped and doesn’t even seem to cover half the smaller disk of the Sun visible from Mars. 

And so we come to appreciate the broader sense of “here”.  Some planet, somewhere, may have as wonderful an astronomical experience of a total stellar eclipse by one or more of their moons.  Those eclipses may turn day into night for minutes or hours somewhere.  But it’s a long way from here.  Light-years away.  Human lifetimes of travel, centuries of traverse across the void.  Nowhere near here.  And this is another gift to appreciate on April 8.  Once in a lifetime in this city or state.  Hours of air travel for the next ones visible on Earth.  And no other place besides Earth that we can expect to get to in this century.  Or the next one. 

This has been a public service announcement.