A blood-red moon will hang close in the sky with the Red Planet Monday night, thanks to the chance coincidence of two rare astronomical phenomena. The moon is due to fall under Earth’s shadow that night (actually the early hours of Tuesday morning) in a total lunar eclipse, one of two such eclipses in 2014. By fluke, Monday is also the date of Mars’s closest approach to Earth, when our neighboring planet should appear larger and brighter than usual.
Stargazers in North and South America should have a fine view of both events, weather permitting. If you plan to catch the sight, consider snapping a photo and sharing it with us below. We plan to post a gallery of the best shots at ScientificAmerican.com on Tuesday.
Total lunar eclipses occur when the sun, Earth and the full moon align in a row, with Earth in the middle. When the moon passes directly through Earth’s shadow, sunlight cannot reach it directly, so it doesn’t shine as usual. The moon doesn’t disappear, either, however, because some of the sun’s light reaches it indirectly, after being bent around the edges of Earth through our planet’s atmosphere. This effect causes the moon to glow a coppery red, for the same reason that sunsets are crimson-hued: When light travels through the thickest part of Earth’s atmosphere, blue light is scattered but red shines through.
The lunar eclipse show will begin around 2 a.m. EDT on Tuesday (April 15), and last about three hours. The moment of totality, when the moon is perfectly aligned in the center of Earth’s shadow, called the umbra, occurs at 3:45 a.m. EDT.
Whether you’re a veteran skywatcher or a novice stargazer, a total lunar eclipse is a sight to see. It’s easy to spot, visually stunning, and poses no hazard to you (in contrast to a solar eclipse, which requires safety viewing equipment). Plus, for viewers in North and South America, this eclipse presents a rare chance to see it from start to finish during our nighttime hours. The next time a total lunar eclipse will be viewable by the entire continent is in 2019.
Add to that the close alignment of the extra-bright Mars, and you’ve got a sight not to be missed. The Red Planet will hang just north of the moon in the sky, separated by a scant three degrees, in front of the constellation Virgo.
So grab your camera and share your view with us.