नवीनतम
India to witness total lunar eclipse on Sep 7
NEW DELHI [Maha Media]: On Sunday night, September 7, 2025, India will witness a spectacular natural phenomenon—a total lunar eclipse—which can be safely viewed with the naked eye, binoculars, or a telescope. A lunar eclipse occurs when the Earth comes exactly between the Sun and the Moon. The shadow of the Earth then falls on the Moon, eclipsing it for some time.
This event will be visible from all parts of India, which is relatively rare. The previous total lunar eclipse widely visible from India occurred in 2018, and the next one will be seen only on December 31, 2028.
In an exclusive interview with ETV Bharat, Niruj Mohan Ramanujam, Scientist-E and Section Head at IIA-SCOPE, Indian Institute of Astrophysics, gave detailed insights into the upcoming lunar eclipse, explaining how lunar eclipses occur, their timing, and why this one is special, including scientific explanations for the red hue and how the colour gives information about Earth's atmosphere.
How lunar eclipses occur
When the Moon passes through Earth’s shadow, it moves through two distinct regions:
* Penumbra – the outer, fainter part of the shadow
* Umbra – the inner, darker part of the shadow
The Moon first enters the penumbra, then the umbra, and finally emerges from them in reverse order.
In the penumbra, the dimming of the Moon is very slight and often hard to notice, whereas in the umbra, Earth’s dark shadow covers the Moon, making it appear dramatically different.
Time to witness the lunar eclipse on September 7
The penumbral eclipse will begin at 8:58 PM. Since the dimming of the Moon will be less than 10 per cent, it will be difficult to notice this phase with the naked eye. The actual partial eclipse, when the Moon enters Earth’s umbra (the darker central shadow), will begin at 9:57 PM. It will take about an hour for the Moon to move fully into the umbra, reaching complete immersion at 11:01 PM.
The total lunar eclipse will begin at 11:01 PM and will last for about 82 minutes, as the Moon crosses from one edge of the umbra to the other. The total phase will end at 12:22 AM, after which the Moon will start to emerge from the umbra. It will enter the penumbral phase (the faint outer shadow) at 1:26 AM, which will conclude at 2:25 AM.
What makes this eclipse unusual
Ramanujam said, “During totality (when the Moon is entirely inside the umbra), we might expect the Moon to disappear completely. Instead, it usually glows a deep red or copper colour. The exact shade varies from one total lunar eclipse to another.”
He said that this striking red hue occurs for the same reason that the sky is blue, while sunrises and sunsets are red—known as Rayleigh scattering. Dust in Earth’s atmosphere scatters shorter-wavelength blue light much more than longer-wavelength red light. As sunlight travels through Earth’s atmosphere during the total Lunar Eclipse, much of the blue light is scattered away, leaving red light. Sunlight passes through Earth’s thin atmosphere, where blue light is scattered into our own atmosphere. The remaining red light is bent (refracted) and falls on the eclipsed Moon. Thus, the red glow we see on the Moon is effectively the combined light of all the sunrises and sunsets on Earth at that moment.
Earth’s shadow is about 2.5 times wider than the Moon’s diameter. Depending on whether the Moon crosses near the centre or the edge of the shadow, the duration and depth of the eclipse vary. This upcoming eclipse is of medium duration, with a totality lasting about 82 minutes.
Why are lunar eclipses important to astronomers?
Ramanujam explained that lunar eclipses are important for researchers, especially atmospheric scientists; the colour of the Moon during a total lunar eclipse is of particular interest. By analysing its hue and brightness, they can infer the amount of dust and aerosols present in Earth’s atmosphere at that time.
For instance, during one lunar eclipse several decades ago, the Moon appeared almost completely black. This unusual darkness occurred because a major volcanic eruption had recently injected large amounts of dust and particles into the atmosphere worldwide. Lunar scientists also study the sudden temperature change during the eclipse to infer the conduction properties of the lunar surface.
Eclipses are special occasions when astronomers can share the wonder of the cosmos with everyone,” Ramanujam said. “A lunar eclipse, in particular, can be observed easily with the naked eye, without the need for any equipment. This makes it an important opportunity for astronomers like me to engage with the public.”
