Total Lunar Eclipse On Pi Day: When To Look Up In MA

MASSACHUSETTS - A “pi in the sky” lunar eclipse event — a mathematics lesson and a “blood moon” skywatching extravaganza — is teeing up in Massachusetts late Thursday night and early Friday morning.

It’s a nerdy but delightful coincidence that a significant portion of the eclipse will take place on Pi Day, which is celebrated annually on March 14. This day honors the mathematical constant pi (π), which plays a crucial role in astronomical calculations. March 14 is referred to as Pi Day because the date is often written as 3/14, aligning with the first few digits of pi (3.14).

Pi is used to calculate things like the circumference of a circle or the volume of a sphere. In a real-world application, NASA scientists use pi to predict the path of the eclipse and the duration of totality with greater accuracy.

Assuming sky conditions permit it in the Commonwealth, we’ll see 65 minutes of totality, starting at 2:26 a.m. local time. The National Weather Service forecasts cloudy conditions overnight Thursday and Friday.

In a total lunar eclipse, the moon moves into the inner part of Earth’s shadow, or umbra, bathing the moon in darkness. According to NASA, some of the sunlight passing through our planet’s atmosphere reaches the moon’s surface, giving it a crimson-red “blood” color.

To calculate totality, NASA scientists incorporate pi into complex mathematical models that account for the circular geometry of Earth and its moon. This allows them to precisely determine the moment the moon is fully covered by Earth’s shadow during a lunar eclipse, essentially using pi to calculate the circumference of Earth’s shadow and its alignment with the moon’s path through it.

Residents of the Commonwealth — all of North America, in fact — will be able to see it from start to finish. Here’s what to expect, according to NASA:

Penumbral phase: The moon enters Earth’s fuzzy outer shadow and loses brightness. This phase lasts from 11:57 p.m. EDT on March 13 until 1:09 a.m. on the 14th.

Partial phase: The moon begins to enter Earth’s darker umbral shadow and begins to turn red from 1:09 a.m. to 2:26 a.m.

Totality: The entire moon is within Earth’s shadow from 2:26 a.m. to 3:31 a.m.

Partial phase: The spectacle reverses with another partial phase from 3:31 a.m. to 4:47 a.m.

Penumbral phase: From 4:47 a.m. to 6 a.m., the moon will exit Earth’s shadow.

The space agency’s scientists and engineers use pi in multiple other ways, including planet exploration. The NASA Pi Day Challenge includes a riddle that can only be solved using the mathematical constant and other educational resources.

NASA uses pi extensively to calculate the trajectories for space exploration, including in missions that send spacecraft to other planets, drive rovers on Mars, and determine what planets are made of and the depth of alien oceans.