How to watch tomorrow’s early-morning full eclipse, the last until 2025

The final total lunar eclipse until 2025 will happen in the cold dark of Tuesday morning, according to NASA.

An eclipse of the moon happens when earth blocks the sun’s light from reaching the moon. There will be still be partial and penumbral eclipses after Tuesday morning and before March 14, 2025, but the complete moon will not fall into the darkest part of Earth’s shadow — called the umbra — for years.

When earth’s shadow moves across the moon, the white ball of rock turns red — often called a blood moon. The red color is caused by the wavelength of light scattered by the atmosphere. During daylight the sky is blue because of that light’s shorter wavelength, scattered by earth’s atmosphere.

During sunset the light must pass through more atmosphere and travel further, showing yellow, orange and red wavelengths to human eyes. NASA explains why an eclipse looks red:

During a lunar eclipse, the Moon turns red because the only sunlight reaching the Moon passes through Earth’s atmosphere. The more dust or clouds in Earth’s atmosphere during the eclipse, the redder the Moon will appear. It’s as if all the world’s sunrises and sunsets are projected onto the Moon.

 

No special equipment is required to observe a lunar eclipse, which unlike an eclipse of the sun, is completely safe to look at. Utahns will have a view of the moon as it passes through the full shadow, if local cloud cover cooperates.

Forecasts are for partly cloudy skies starting at approximately 11 p.m. Monday, giving the Beehive State a possibility to observe the full eclipse. It will be visible across North America and Central America, but in Puerto Rico the moon will set after totality starts, NASA said.

Alaska and Hawaii residents will be able to see every stage of the eclipse while Asia, Australia and New Zealand can also view it.

If it is cloudy, the eclipse can be viewed via NASA’s YouTube page.

Utah’s moon-viewing timeline, all listed times are Utah local time:

• If clouds stay out of the way, Utahns will be able to observe the moon enter Earth’s outer shadow with a subtle dimming at 1:02 a.m. Tuesday.
• At 2:09 a.m., the moon will enter the umbra part of the shadow and the eclipse begins. The portion of the moon inside the umbra, a bite-sized bit, appears very dark.
• Then at 3:17 a.m., the entire moon moves into the umbra and the sphere will turn a red hue. A telescope or binoculars will help with an enhanced viewing experience. Cameras with tripods can grab exposures lasting several seconds.
• At 4:42 a.m. the moon exits the shadow and the red color will fade, with a bite appearing extra dark of the part that remains in deep shadow.