Lunar Eclipse 2025: When, Where and Why the Moon Turns Red

September 8, 2025

On September 7–8, the Moon will transform into a glowing red orb as a total lunar eclipse—famously called a Blood Moon or Chandra Grahan—graces the skies. Visible across the whole of India, this celestial event combines the magic of astronomy with centuries of cultural traditions. From why the Moon turns red to how long the eclipse will last, here’s everything you need to know before you step outside and look up.

What Exactly Is a Total Lunar Eclipse?

A total lunar eclipse occurs when the Earth moves directly between the Sun and the Moon, casting its shadow fully on the lunar surface. Unlike a solar eclipse, which blocks out sunlight for a brief period in specific locations, a lunar eclipse can be seen from anywhere on the night side of the planet.

During such an alignment, sunlight passing through the Earth’s atmosphere gets refracted and scattered. While shorter wavelengths of light—like blue and violet—are filtered out, the longer wavelengths, such as red and orange, bend toward the Moon. This paints the lunar surface in shades of copper, crimson, or rust, creating the striking “Blood Moon” effect.

Astronomers note that no two lunar eclipses look exactly alike. The intensity and colour of the eclipse can vary depending on atmospheric conditions, such as levels of pollution, volcanic dust, or even recent wildfires around the globe.

When and Where to Watch

The lunar eclipse of September 7–8 will unfold over several hours. It begins with the penumbral phase, as the Moon enters Earth’s outer shadow, followed by the partial phase when a visible chunk of the Moon starts to darken. The highlight is the “totality” phase, lasting for more than an hour, when the Moon is completely enveloped in Earth’s shadow and glows a deep red.

For India, the timing is especially favourable. The eclipse will be visible from start to finish across the country, giving skywatchers an uninterrupted view of the entire event. Those in Western Australia will also see the eclipse in full, while regions of Europe, Africa, Eastern Australia, and New Zealand will witness partial phases.

Best of all, lunar eclipses are completely safe to view with the naked eye. Unlike solar eclipses, no protective glasses or equipment are needed. Binoculars or telescopes, however, can enhance the viewing experience and bring out details of the lunar surface bathed in its unusual hue.

Why Does the Moon Turn Red?

The distinctive reddish glow of the Moon during a total lunar eclipse is a direct consequence of Earth’s atmosphere acting as a filter. As sunlight travels through the thick layer of gases surrounding the planet, it bends around the edges and reaches the Moon. In this process, the bluer wavelengths scatter away, while the reddish light survives the journey.

This same phenomenon—known as Rayleigh scattering—is what makes the sky appear blue during the day and sunsets appear red. In a sense, the Moon during a total lunar eclipse is simultaneously experiencing all of Earth’s sunsets and sunrises projected onto its surface.

Cultural and Religious Significance

In India and many other parts of the world, lunar eclipses are not only astronomical but also cultural events. In Hindu tradition, the phenomenon is called Chandra Grahan. It is often accompanied by rituals such as fasting, reciting prayers, and observing restrictions on cooking or eating during the eclipse period. Temples in some regions close their doors during the event and reopen after ritual purification.

Astrologers also attach symbolic meanings to lunar eclipses, interpreting them as markers of change or transformation. While scientists emphasise the purely physical nature of the eclipse, its resonance in faith and folklore continues to shape how communities observe it.

Why This Eclipse Matters

Total lunar eclipses are not an everyday occurrence. While partial eclipses happen more frequently, a total eclipse visible across such a large swathe of the globe—including all of India—is relatively rare. For astronomers, it is a chance to study atmospheric conditions, as the colour and brightness of the eclipse provide indirect clues about the state of Earth’s atmosphere. For the public, it is a chance to connect with both science and tradition under the open sky.

Whether seen through the lens of astronomy or spirituality, the September 7–8 Chandra Grahan promises to be a memorable spectacle. For those willing to stay up late and look skyward, the “Blood Moon” will offer a striking reminder of the intricate cosmic dance between the Earth, Moon, and Sun.