Solar Eclipse

What is a solar eclipse?

A solar eclipse happens when the Moon passes between the Earth and the Sun and covers part or all of the Sun's disc. It always falls on Amavasya, but not on every Amavasya — the Moon's orbit is tilted about 5° to the Earth's, so an eclipse occurs only when the New Moon lands near the Rahu–Ketu axis.

The phases shown

Begins is the moment the shadow first touches the disc, Maximum is when coverage peaks, and Ends is when the shadow leaves entirely. Totality begins and Totality ends appear only for total or annular eclipses — they bound the stretch when the covering is at its fullest.

All times are in the local time of the place you have selected. The global figures describe the event as it happens somewhere on Earth; local visibility is reported separately, because not every eclipse is visible from every location.

The calculated attributes, explained

Magnitude

The fraction of the Sun's diameter covered by the Moon at maximum eclipse. 1.0 or above means the disc is fully covered — a total eclipse. 0.545 means just over half the Sun's width is hidden.

Obscuration

The fraction of the Sun's visible area that is covered — not its width. Because a disc's area grows with the square of its radius, obscuration is always lower than magnitude for a partial eclipse: 54.5% of the diameter covered works out to about 44% of the area.

Sun diameter coverage

Magnitude expressed as a percentage — how much of the Sun's width the Moon hides at maximum.

Moon / Sun diameter ratio

How large the Moon appears against the Sun. Both vary in apparent size through their orbits; above 1.0 the Moon can cover the Sun completely (a total eclipse), below 1.0 a ring of Sun remains visible around it (annular).

Saros series

Eclipses repeat on an 18-year, 11-day, 8-hour cycle called a Saros. The series number identifies the family this eclipse belongs to, and the second figure is its position within that family — so 124 / 55 is the 55th eclipse of Saros 124.

Umbral (central) shadow diameter

The width of the Moon's full shadow where it touches the Earth. Only observers inside this track see totality; everyone else sees a partial eclipse.

Sun altitude (apparent / true)

How high above the horizon it stands, in degrees. The apparent figure includes atmospheric refraction, which lifts a low body slightly; the true figure is the geometric position. A low altitude means the eclipse happens close to the horizon and may be hard to see.

Sun azimuth

The compass direction to look, measured clockwise from north — 90° is due east, 180° due south, 270° due west.

Lunar elongation

The angular separation between the Sun and the Moon in the sky. It approaches 0° at a solar eclipse (New Moon) and 180° at a lunar eclipse (Full Moon), which is why eclipses can only occur at those points.

Sutak Kaal

Sutak for a solar eclipse begins about 12 hours (four prahar) before the eclipse starts. Auspicious work, touching temple images and cooking are traditionally suspended during it. Importantly, Sutak is observed only where the eclipse is actually visible — if it cannot be seen from your city, the tradition holds that Sutak does not apply.

Viewing safely

Never look at the partial or annular phase with the naked eye, through sunglasses, or through exposed film. Use only certified solar filters (ISO 12312-2) or a projection method.