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Lunar eclipse Oct. 27 should be spectacular, NMSU astronomer says

A total eclipse of the moon on Wednesday, Oct. 27, should provide a "fairly spectacular evening event," says veteran skywatcher Kurt S.J. Anderson, professor of astronomy at New Mexico State University.


d even though the show will be quite visible to the unaided eye, the NMSU Department of Astronomy is inviting enthusiasts to increase their enjoyment by watching it from the campus observatory, where members of the department will be on hand beginning at 9 p.m. to answer questions and operate the telescopes.
The Clyde W. Tombaugh Observatory is located on the east side of Williams Avenue, between Gregg and Wells streets. Parking is available along Williams Street. The observatory will be in use for astronomy classes until 9 p.m., when it will be opened to the public.
The total part of the eclipse will last a full hour and 21 minutes. "Although the eclipse should be observable throughout the United States, our clear Southwestern skies should provide an eerily impressive show," Anderson said.
Moonrise will occur about 5:44 p.m. MDT and the eclipse will begin at 6:06 p.m. when the full moon enters the penumbral shadow of Earth. This phase of the eclipse will appear as a progressive dimming of the moon's brightness.
The moon enters Earth's umbral shadow at 7:14 p.m. and observers will see the sharp edge of this darker shadow of Earth begin to move across the face of the moon, beginning on the moon's eastern edge.
"The umbra is that part of the shadow within which an astronaut on the moon would see the Earth completely covering the sun," Anderson said.
The eclipse will become total, with all of the moon in the umbral shadow, at about 8:23 p.m. The total eclipse will last until about 9:45 p.m., with the midpoint at 9:04 p.m.
Between 9:45 and 10:54 p.m. the moon will move out of the umbra, and finally the penumbral part of the eclipse will end just after midnight.
During totality, the moon probably will assume a reddish hue because of sunlight refracted (bent) by Earth's atmosphere.
"An observer on the moon during this part of the eclipse would see the Earth as a dark disk completely obscuring the sun, but surrounded by a bright red ring of refracted sunlight," Anderson said. "The Earth's atmosphere acts like a prism to bend this sunlight toward the moon, but absorption and scattering in that atmosphere removes all but the reddest wavelengths of light."