Dazzling Blood Moon Eclipse on September 7-8
On September 7-8, 2025, the night sky will put on one of its most dramatic shows this year—a total lunar eclipse. During this phenomenon, the moon glows a deep, reddish-orange, causing it to be popularly known as a Blood Moon.
The last time a total lunar eclipse was visible in the Philippines was in November 2022, almost three years ago. While the last total lunar eclipse occurred in March 2025, it was not visible in the Philippines. This time, the Blood Moon will be fully visible across Asia, Australia, and eastern Africa.
According to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), the event will begin at 11:27 p.m. on September 7 and end at 4:57 a.m. on September 8, when the moon enters and exits the penumbra, the outer, lighter part of Earth’s shadow. Here, skygazers can expect to see the moon begin to darken.
The moon will enter totality, or the “Blood Moon phase,” at around 1:30 a.m. on September 8, when the moon enters the umbra, or the inner, darker shadow of the Earth. This will span 1 hour, 22 minutes, and 54 seconds, ending at around 2:53 a.m.
Total lunar eclipses occur when the Earth slips between the full moon and the sun, forming a straight line. Here, the moon passes completely into Earth’s shadow. However, instead of disappearing, the moon turns red. This is due to a phenomenon called Rayleigh scattering.
In 1859, John Tyndall observed that when light passes through a fluid with tiny particles, blue and violet light scatter more strongly, while the light that passes through the fluid appears red. Building on this, in 1871, British physicist Lord Rayleigh developed a mathematical explanation showing that shorter wavelengths of light, such as blue and violet, scatter more than longer wavelengths, like red. This effect was named Rayleigh scattering in his honor.
Thus, in a blood moon, as sunlight passes through our planet’s atmosphere, blue light is scattered by tiny air molecules, while the red and orange wavelengths remain. They are refracted (bent) into Earth’s shadow and cast onto the moon’s surface. As a result, the moon glows a bright reddish-orange: Rayleigh scattering on a planetary scale.
Unlike solar eclipses, viewing lunar eclipses does not require special eye protection—only a clear view of the sky and patience. Binoculars and telescopes may also be used to further enhance the view.
So, instead of doomscrolling at 12 a.m., try to step outside and view the Blood Moon!
Sources:
https://www.wired.com/story/how-to-see-the-total-lunar-eclipse-and-blood-moon-on-september-7/
https://www.ebsco.com/research-starters/chemistry/rayleigh-scattering
