Rare celestial event on Wednesday

In a rare celestial event, the planet Mercury will on Wednesday transit the Sun as viewed from Earth.

On an average, there are 13 such transits of Mercury in a century and the event would be visible from India between 1043 and 1600 IST on Wednesday, an Indian Institute of Astrophysics (IIA) release said in Bangalore on Tuesday.

"Though not as exciting as a solar eclipse or a comet passing by, this event is of interest in its own right."

"It is very difficult to observe as the planet is small (a mean radius of 2,438km compared to 695,950km of the Sun)

and will appear as a very small dot against the bright disc of the Sun. It will be virtually indistinguishable from a sunspot," IIA said.

The institute has asked people to use adequate filters before viewing the celestial event with a telescope.

Transits of only Mercury and Venus are visible from earth and the transit of Venus, which is bigger in size, is rarer.

"Interestingly, a transit of Venus is due on June 8, 2004, which will be visible from India," it said.