Media advisory: Saturday morning's 'blood moon' eclipse will be a short show

LAWRENCE — An “unusually short” total lunar eclipse will occur before dawn Saturday, April 4, lasting all of about 10 minutes.

Bruce Twarog, professor of physics and astronomy at the University of Kansas, is available to discuss the unique event with media. Twarog’s research centers on observational astronomy and astrophysics. He concentrates on the application of precision photometry with intermediate-bandwidth optical filters to understand stellar and galactic evolution.

“It will be visible from Lawrence in the two hours before sunrise,” Twarog said. “Lunar eclipses, when the Earth is situated between the sun and the moon so that the moon sits within the shadow of the Earth, occur regularly about two weeks after a solar eclipse, when the moon passes between the sun and the Earth and the Earth sits in the shadow of the moon. The Earth experienced a total solar eclipse on March 20, and in the two weeks since, the moon’s orbit has carried it to the side of the Earth opposite the sun.”

According to Twarog, lunar eclipses are visually subtler than eclipses of the sun.

“Solar eclipses are visually more spectacular, and they typically last only a few minutes because the moon fills almost exactly the same area on the sky as the sun, and the light passing by the edge of the moon doesn’t pass through an atmosphere, so the shadow has a sharp edge,” he said. “By contrast, the Earth, as seen from the moon, is significantly larger than the sun, so a lunar eclipse can last much longer, and light passing through the Earth’s atmosphere is bent around the edge, producing illumination of the moon and making the shadow less distinct.”

The KU scientist said the “blood moon” effect results when blue light from the sun is scattered by the Earth’s atmosphere while the red light passes through: “The moon takes on a reddish tint, leading to the designation of a ‘blood moon,'" he said.

Surprisingly, since the alignment of the sun-Earth-moon system isn’t ideal, totality for this eclipse will only last about 10 minutes. From Lawrence, the lunar brightness will start to decline about 4:40 a.m.; partial eclipse, when a segment of the moon’s disc is blocked, will start around 5:15 a.m., and total eclipse will run from 6:55 a.m. to 7:05 a.m. The total eclipse with overlap with sunrise at 7:01 a.m. 

To schedule an interview with Twarog, contact Brendan M. Lynch via brendan@ku.edu or 785-864-8855.