Enjoying EarthSky? Subscribe.

270,538 subscribers and counting ...

A shadow-band project for August 21

Shadow bands are elusive ripples of alternate light and dark, flitting over the ground or the sides of buildings during a total solar eclipse. How to take part in an International Shadow Band Campaign during the August 21 eclipse.

Shadow bands are seen to ripple across a house in Sicily during a total eclipse in 1870. Image from Mabel Loomis Todd’s Total Eclipses of the Sun, 1894, via Fred Espenak.

Dr. Satyendra Bhandari, of Ahmedabad in India, wishes to organize an International Shadow Band Campaign during the approaching total eclipse. If you expect to be in or very near to the track of totality on August 21, 2017, he encourages you to write to him: space.scientist @ gmail.com

He will no doubt send instructions on the simple observations needed, and some of his interesting thinking about shadow bands. He is working on a Manual of Shadow Band Observations and once shared a draft copy of it on SEML (the eclipse listserve). He is also preparing an introductory book on the subject.

He regards shadow bands as one of the important effects of eclipse on the Earth environment. The transition between daylight and darkness at sunset is “routine” and gentle, he says, but the transition at the onset of total eclipse is a “shock” to the atmosphere, through which the moon’s shadow is moving with supersonic speed.

Read more about shadow bands via Wolfgang Strickling.

Bottom line: Want to take part in an International Shadow Band Campaign during the August 21, 2017 total solar eclipse. Write to Satyendra Bhandari: space.scientist @ gmail.com

Get ready for the August 21 eclipse with Guy Ottewell’s Understanding of Eclipses

Read more: Total eclipse of sun August 21, 2017

Read more: How much traffic on eclipse day?

Guy Ottewell