DHAKA: Millions of people are set to see an astronomical triple play when a rare total solar eclipse occurs on the same day as the vernal equinox, and a supermoon makes an appearance.

The moon will also reach perigee on Friday, the point where it is closest to the Earth, creating a supermoon -- albeit a dark one -- that will add another element to the total solar eclipse.

A total eclipse occurs when the moon comes between Earth and the sun, casting a lunar shadow onto the Earth’s surface along a narrow, 62-mile-wide (100-kilometer) path. Because this “black hole” effect lasts for only a couple of minutes, totality ends up being a truly rare event for any single spot on Earth—occurring about once every three centuries for each geographical location.

Friday’s eclipse will race across remote regions of the North Atlantic and the Arctic Ocean, so only a relatively few lucky souls will be able to see it. But people in large parts of Europe and in northern areas of Africa and Asia will get to enjoy at least a partial solar disappearing act.

Adding to the uniqueness of the total eclipse, it falls on the vernal equinox, which officially occurs at 22:45 GMT (6:45 p.m. EDT) and marks the beginning of spring. While the occurrence of an eclipse on the equinox is considered a cyclical event and is not that rare, this celestial combination won’t occur again until 2034.

If that isn’t special enough, the sun will be covered by a supermoon, which occurs when the moon is at its perigee, or closest distance to Earth. That makes the moon’s disk appear about 15 percent bigger than average. Most sky-watchers won’t be able to see this supermoon, however. Since a solar eclipse can occur only during a new moon, the supermoon will be visible during the eclipse just as a silhouette in front of the solar disk.

Spring Equinox

Get ready for spring if you live in the northern hemisphere.

The official start of spring, the vernal equinox, will be marked on Friday at 6:45 p.m. ET when the Earth's axis lines up perpendicularly to the sun's rays -- marking one of the two equinoxes that occur each year.

Source: nationalgeographic, abcnews.go.com

BDST: 2250 HRS, MAR 18, 2015