Unique Aspects and Their Timing

Moon's Shadow

  • The shadow of the moon rushes toward you at about 1000mph.
  • It's "just like a thunderstorm coming in."

Darkening Skies

  • The skies darken–but your eyes adjust!
Photo sequence of the July 1991 eclipse. Camera aperture and exposure time set. Note the calming of the water. Last photo was not dark to the naked eye (it was a few minutes before totality.) (Photos by Barbara Andereck)

Sharp Shadows

  • Note shadows of individual hairs:
(Photo by Barbara Andereck)

Twilight Colors

Twilight colors as totality approaches, from August 2017 eclipse. (Photo by Hilary Soiefer)

Shadow Bands

  • Shadow bands may be visible for a minute or two before totality (second contact). These are interference phenomena seen on a flat surface when only a sliver of the sun remains:
(Left illustration courtesy of Sky & Telescope Magazine, right photo by Dr. Wolfgang Strickling)

Bailey's Beads and Diamond Ring

  • Seen just before second contact (start of totality) when the last portion of the photosphere (sun's "surface") can be seen through the moon's craters:
(Photos courtesy of Sky & Telescope Magazine)


  • Chromosphere glowing (pink) hydrogen gas just above the sun's photosphere ("surface"):
(Photo by Vishnu Reddy)


  • The hot glowing ionized gas being "blown" from the sun by the "solar wind."  The corona looks wispy and may extend 5-6 solar diameters from the sun:
(Photo by Dennis DiCicco)
(Photo by Sean Walker)


  • Streams of hot hydrogen gas ejected from the photosphere ("surface") of the sun—glowing pink:
(Left photo by Barbara Andereck, right photo courtesy of NASA)


  • Venus about 15° down and to the right (closer to the horizon and west)
  • Jupiter about 30° up and to the left
  • Saturn and Mars halfway between Venus and the horizon on the line going through the sun (Mars is closer to the horizon)

Bright Stars

  • Sirius near the SE (or ESE) horizon (altitude about 11°)
  • Orion in the SE
Screenshot from Stellarium.

Temperature Drop

Vishnu Reddy (University of Arizona) took temperature readings with a small probe throughout the 2017 eclipse in Glendo, WY. Notably, temperatures continued to drop for about 10 minutes after totality ended. (Image by Vishnu Reddy and available at Sky & Telescope)

Animal Responses

  • Animals think night has come (or is coming) and act accordingly.

Department Contact Info


Schimmel/Conrades Science Center
Delaware, OH

Department Contacts

Chair: Brad Trees
Professor of Physics & Astronomy
Schimmel/Conrades Science Center 139
740-368-3779 | brtrees@owu.edu

Academic Assistant: Joshua Seiders
Schimmel/Conrades Science Center 201
740-368-3907 | jjseiders@owu.edu