Partial Solar Eclipse In India And Elsewhere: Essential Things To Know

The Moon will take a solid bite off the Sun today (25 October) — at least that’s how it will appear to us briefly from our vantage point looking up from the surface of the Earth.

India is among parts of the world — Europe, North-East Africa, and West Asia — that will witness a partial solar eclipse, the last solar eclipse of the year. The extent of the visible eclipse will vary from one place to another.

“The coverage is maximum in Russia, and decreases as you go southwards and eastwards from Ladakh and Jammu & Kashmir. The eclipsed fraction of the Sun’s disk decreases from about 55% in Leh to just 10% in Bengaluru and 2% in Trivandrum,” a poster by the Indian Institute of Astrophysics (IIA), Bengaluru, explains.

The celestial phenomenon will be visible in India from 4.29 pm to 5.42 pm. However, different parts of the country will see it at different times within this time frame. For example, the eclipse will be visible in Bengaluru in the western evening sky from 5.12 pm until sunset at 5.55 pm. 

Check the viewing time in your region so you don’t miss the natural phenomenon. (Viewing the eclipse requires protection.)

Eclipse basics

A solar eclipse occurs when the Moon passes between the Sun and the Earth. When this happens, the Sun’s light is blocked and a shadow is cast on our planet. The sky becomes dark, as if it were dusk or dawn.

Extending this to a “partial” solar eclipse: the Moon doesn’t cover all of the Sun’s face — which would be the case with a total solar eclipse. Rather, it covers a part of the Sun, with our super star peeking out from behind the Moon (as seen by us).

In a partial solar eclipse, the Sun, Moon, and Earth are not perfectly lined up. This feature makes the phenomenon different from an annual solar eclipse, wherein the Moon passes between the Sun and Earth, but when it’s at its farthest point from the blue planet.

The Sun and Moon appear similar in size in the sky only because of the relative distance and size. While the Sun is 400 times bigger than the Moon, it is also 400 times further away from Earth.

Note that a solar eclipse can only occur on new Moon days.

Safe ok please

With the eclipse basics out of the way, here’s a critical point: it is not safe to look directly at the Sun without specialised eye protection.

Not just looking up directly, but even viewing the eclipse through a camera lens, binoculars, or a telescope without the protection of a special-purpose solar filter is a no-no.

The concentrated solar rays will burn through and cause severe injury to the eye.

If you must see the eclipse, use safe solar viewing glasses or “eclipse glasses,” which are very different from regular sunglasses. Even eclipse glasses must be inspected well before use.

The best-case scenario is to view the eclipse under the supervision of an expert. (More on safe viewing here.) Check with your local astronomical observatory or facility for support in solar viewing.

However, as long as you don’t look at the Sun, eclipses don’t pose any harmful effects.

Catch it live

Several Indian institutions will be streaming the eclipse live; these will be safe to watch from the comfort of your homes. 

IIA, Bengaluru, will be live-streaming the partial solar eclipse from its Indian Astronomical Observatory in Hanle, Ladakh, on its YouTube channel.

The stream, scheduled to run from 4 pm to 5.30 pm, will also feature IIA astronomers talking about the eclipse and answering questions live.

In addition, there’s a solar eclipse app on Google Play. The app was developed by Alok Mandavgane for the Public Outreach and Education Committee of the Astronomical Society of India (POEC). It provides information about eclipses as well as eclipse circumstances at a location of your choice.

(Check this IIA YouTube playlist for information about solar eclipses in many Indian languages.)