Rare celestial event after 150 years

TT, Siliguri: The Sky Watchers' Association of North Bengal (SWAN) has made elaborate preparations for viewing and recording total lunar eclipse (TLE) to be witnessed on January 31 across the country.

"We will install telescopes for viewing TLE on the premises of Ramakrishna Ashram in Sahudangi located on Siliguri outskirts. Our volunteers would be there with other equipment like cameras to click photos and record videos. They will also demonstrate to people on the technicalities behind each phenomenon during the eclipse," said Debasis Sarkar, secretary of the SWAN.

This year is going to be rare total lunar eclipse sight as the TLE can been seen with "blue moon" and "red moon", said Sarkar.

"Lunar eclipses keeps on occurring at regular intervals but the last blue moon with TLE was witnessed back on March 31, 1866, (152 years ago) while the next such eclipse will occur on December 31, 2028," Sarkar added.

The SWAN secretary pointed out that the term "blue moon" is used when there is a second full moon in a calendar month . It doesn't mean that the moon will turn blue during the TLE.

Sarkar informed the moon during the TLE will look reddish in colour which is why it is termed as "red moon". "The moon turns red because a small amount of red light remains present due to refraction of sunlight through the earth's atmosphere, when it comes exactly between the sun and moon," he pointed.

This rare celestial event can be witnessed in the evening hours of January 31 between around 5.40pm to 7.30pm, sources said.