Mark Hollabaugh is author of The Spirit and the Sky: Lakota Visions of the Cosmos (Nebraska, 2017). His book examines nineteenth-century Lakota astronomy and its connection to their spirituality. The Spirit and the Sky will be available in paperback this October. Mark is hoping for clear weather on the nights of August 11 and August 12.

 

Summer is an enjoyable time to get outside and explore the night sky. Vacations often take us far from city lights and the nighttime environment is usually pleasant for late night star gazing. It’s easy to catch a falling star and many people associate meteors with late summer because a very dependable meteor shower occurs every August.

Every year around August 11 or 12, the Earth encounters a celestial dirt pile left in our orbit by Comet Swift-Tuttle, a comet discovered in 1862 by Lewis Swift and Horace Parnell Tuttle.[1] The tiny dust grains and pea-sized debris that were expelled from the surface of the comet and are attracted by the Earth’s gravitation field. As this cometary debris makes its way into our atmosphere, friction superheats the debris and it vaporizes with a bright display of light. On any average summer night, you can probably see four to five random meteors per hour, but during the Perseid shower you can usually witness 60 to 70 flashes of light across the sky per hour. A meteor shower takes its name from the constellation from which it appears to radiate, in this case, Perseus.[2]

In the nineteenth century, the Lakota witnessed and recorded sporadic meteors and meteor showers. One of the most significant showers was the Leonid shower in November 1833. Some Native Americans referred to this as “The Night the Stars Fell” and recorded the event on their winter counts. In fact, the 1833 Leonid shower is one of the most commonly chronicled astronomical display in Lakota and other Plains Indian winter counts probably because it is thought that meteors may have fallen at a rate exceeding 100,000 per hour! Two counts on display at the Buechel Memorial Lakota Museum on the Rosebud Reservation show this event.

Woȟpé is the Lakota word for meteor, and it derives from the verb woȟpá, “to make fall by shooting” or “to shoot down.”[3] This is interesting because of a response some Lakota made to the 1833 shower. Marie Kills in Sight, director of the Buechel Memorial Lakota Museum, told me a story about the 1833 Leonid shower passed on to her by her paternal grandmother Laura Hollow Horn Bear. Grandmother Laura related, “The Lakota fired their weapons into the air when they saw the meteors falling.” The response to the stars shooting down was to shoot back. The motivation might have been to scare away whatever agent was causing the stars to fall.[4]

Here’s how to observe this year’s Perseid shower. First, we’re lucky because there will be a waxing crescent moon and it won’t interfere with observations. In fact, the moon sets at about the time twilight ends at the Badlands National Park. Speaking of national parks, get away from city lights. The bigger the city, the further you’ll need to go. Many state parks and national parks and monuments are in remote dark sky areas and host special observing events for Perseid fans. Because these viewing sessions are at night, you may need to camp in the park or stay at a nearby lodge. Check in advance about special programs.

Go outside both August 11 and August 12 after the sun has set and it’s totally dark. The best observing is usually after 1:00 a.m. local daylight time, but you could start your observing as soon as it is dark. Find a comfortable outdoor recliner chair, or, lay on your back on the ground.

Perseus will be in the eastern sky, but look away from Perseus, perhaps towards the northwest or straight up (the zenith), because you’ll observe more meteors away from the radiant. If you are observing with others, don’t all look in the same direction. You should see several meteors per minute because some predictions suggest this year will be especially productive.

If you wish to photograph the shower, use a DSLR with a fast lens, f/2 or better, a tripod, and remote release for your camera (to avoid camera jitter). Use an ISO of at least 400, perhaps even 800 to 1600 depending on your lens. The higher the ISO the more noise you’ll introduce into your photo, but you’ll capture more faint meteors. If you have, for example, an f/1.8, 18 mm to 35 mm zoom lens, use aperture priority so your camera doesn’t automatically adjust the f/ ratio, set the lens to aperture f/1.8 and 18 mm focal length.

Using a remote release, leave the shutter open for about ten minutes and you’ll see defined star trails and many flashes. If you use a shorter exposure time, say ten to fifteen seconds, you’ll get fewer meteors but well-defined constellations. You may need to experiment to see what works best.[5] If you have a GoPro POV camera, it is possible to obtain time-lapse night sky images and combine them into a stunning video.[6]

Stars will show up as streaks of uniform lengths. Meteors will appear as shorter, and probably fainter streaks, at angles to your star trails. The meteor streaks will point back to the radiant in Perseus. If you see a meteor streak that varies in brightness over its length, that is probably due to the meteor breaking up. If you see a long streak running through the entire image, well, that’s an airplane at around 36,000 feet or an Earth-orbiting satellite!

Enjoy the Perseid shower this year. Think about the reactions of the nineteenth-century Lakota to a meteor shower. Hopefully you’ll see a fireball, a very bright meteor that can leave a visible ionization trail that persists for a few seconds. And, I recommend not firing any weapons into the air!

 

NOTES

[1] Tuttle, an astronomer, participated as a geologist in the 1875 Black Hills Expedition where he was identified as “Capt. H. P. Tuttle.” (Charles P. Daly, “The Geographical Work of the World for 1875,” Journal of the American Geographical Society of New York 7, (1875): 31-92)

[2] For more information on observing meteor showers, see Kelly Beatty, The Best Meteor Showers in 2018, http://www.skyandtelescope.com/astronomy-news/best-bet-meteor-showers-for-2018/.

[3] Buechel, Eugene, S.J., and Paul Manhart, S.J. Lakota Dictionary. Rev. ed. (Lincoln: University of Nebraska Press, 2002): 386.

[4] Marie Kills in Sight, conversation with the author, 20 August 2009, St. Francis, SD.

[5] For more detailed information, see How to Photograph Meteors with a DSLR, https://www.amsmeteors.org/meteor-showers/how-to-photograph-meteors-with-a-dslr/.

[6] For detailed instructions, see https://gopro.com/help/articles/How_To/How-to-Use-Night-Photo-Night-Lapse.