Lunar eclipse this Tuesday; last total one for three years

A lunar eclipse occurs when the Earth passes between the sun and moon, casting its shadow onto the moon.

AUSTIN (KXAN) — If you hope to see a total lunar eclipse, Tuesday will be your last chance until March 2025. The eclipse, nicknamed the "blood moon" because of its deep red color, will begin at 2:02 a.m. in Austin, reaching totality at 4:17 a.m.

According to NASA, people in Japan, Alaska and Hawaii will be able to see the total lunar eclipse, while Central Texas will see only a partial eclipse.

A lunar eclipse occurs when the Earth passes between the sun and moon, casting its shadow onto the moon. When the moon enters the darkest part of Earth's shadow, called the Umbra, it will turn a reddish hue.

According to NASA, no special equipment will be needed to view the eclipse. A telescope or binoculars will help. The space administration recommends you get as far away from city lights to see it.

Creating the 'blood moon'

The moon changes color because of the Reyleigh scattering effect. This occurs because light travels in waves, with different colors acting differently. As those waves hit the Earth's atmosphere, the light scatters.

Blue light scatters easily, while red light doesn't. Red light has a longer wavelength and travels easier through the atmosphere.

According to NASA, when the sun is overhead blue light is easier to see. When it is at an angle, the blue light scatters and red light passes through the atmosphere, turning the sky red.

As this light passes through the air, it casts this red light onto the moon. The more clouds in the atmosphere, the redder the "blood moon".

Central Texas and the solar eclipse

While we won't have another total lunar eclipse until 2025, Travis County can look forward to a total solar eclipse in 2024. The eclipse will pass directly over the state on April 8, 2024 at 1:32 p.m.

Unlike a lunar eclipse, a solar eclipse occurs when the moon passes between the Earth and the Sun. Solar eclipses occur every 18 months, with the last one occurring over the U.S. in 2017. Approximately 20 million Americans saw that eclipse.

Texas will be the first state to see the eclipse in 2024, before it passes over the rest of the country.