Jennifer Egan Captures 96% Blood Moon Over Kennebunkport

Q: What hidden atmospheric secrets caused this week's near-total lunar eclipse to glow with a rusty red hue over Maine?

The rusty red glow came from Earth’s atmosphere acting like a giant filter and lens during the near-total lunar eclipse. As the Moon moved about 96% into Earth’s umbra, direct sunlight was blocked. But some sunlight still skimmed through the outer edge of Earth’s atmosphere before bending into the shadow and reaching the Moon. In that process, shorter blue wavelengths were scattered away far more efficiently, while longer red and orange wavelengths passed through and were refracted onto the lunar surface. That is why the eclipsed part of the Moon looked coppery or blood-red over Maine. Astronomers often describe it as the combined light of all the world’s sunrises and sunsets being projected onto the Moon. The effect is the same physics that makes sunsets appear red: atmospheric scattering, commonly called Rayleigh scattering, plus refraction through the atmosphere. The exact shade is not fixed. It depends on “hidden” atmospheric conditions along Earth’s limb at the time of the eclipse, including dust, aerosols, cloudiness and even ozone. Those factors can make an eclipsed Moon appear brighter orange, deeper red or duller brown. Forecasts for this event suggested a moderately bright eclipse, around Danjon L=2 to L=3, meaning the Moon was expected to stay visibly reddish rather than turning extremely dark. Because a thin sliver of the Moon remained outside the umbra, it stayed brightly lit, creating the striking contrast seen in the Maine image.

Q: Why do dramatic blood moons often appear just weeks after a solar eclipse, and when will the next one strike?

Blood moons often appear just weeks after a solar eclipse because both events usually happen in the same “eclipse season” — a roughly 31- to 37-day window when the Sun, Earth and Moon line up near the Moon’s orbital nodes. A solar eclipse happens at new moon, and about two weeks later, at full moon, that same geometry can produce a lunar eclipse. That is why Maine’s partial solar eclipse on Aug. 12 was followed only 15½ days later by the deep partial lunar eclipse of Aug. 27-28. They do not happen every month because the Moon’s orbit is tilted about 5 degrees relative to Earth’s path around the Sun. Most months, the Moon passes slightly above or below the exact alignment needed. During eclipse season, however, the alignment is close enough for a pair of eclipses — sometimes even three — to occur. The “blood moon” color comes from sunlight filtered through Earth’s atmosphere during a lunar eclipse. Blue wavelengths scatter out, while red and orange light bends into Earth’s shadow and reaches the Moon, tinting it coppery or red. As for the next one, the next lunar eclipse will be a subtle penumbral eclipse on Feb. 20, 2027, visible across large parts of the world. But the next dramatic blood-moon-style event comparable to this month’s will take longer: there is no similarly striking umbral lunar eclipse until later, with major total lunar eclipses returning in 2028 and especially in 2029.

1 articles · Updated · WMTW Portland · Aug 28

Jennifer Egan photographed the near-total lunar eclipse over Kennebunkport after clouds made viewing difficult across Maine.
At its overnight peak Thursday into Friday, about 96% of the moon passed through Earth's umbra, leaving most of it a rusty red with a thin bright sliver.
WMUR also captured video of the eclipse in neighboring New Hampshire, offering another view of the event.
The blood moon came just 15 1/2 days after a partial solar eclipse visible in Maine, where totality ranged from 15% to 30% depending on location.