Eye on sky: Did you miss rare blue moon welcoming the new year?

December 2009 had two full moons shining in the night sky — first on December 2,and again on December 31. As revellers across the city bid the year adieu and welcomed 2010,the second full moon of December on New Year’s Eve enthralled sky gazers.

Moreover,the partial lunar eclipse of the blue moon on Thursday night made 2009 even more unique.

“A partial blue moon eclipse is rare. This will not occur again until 2037,” said C B Devgun,director of Science Popularisation Association of Communicators and Educators (SPACE).

The partial eclipse of the blue moon lasted almost two-and-a-half hours,starting from 10.47 pm on December 31 and lasting till 3 am on January 1.

As the glasses clinked on the New Year’s Eve and balloons were about to be released in the night sky,the shadow of Earth slowly crept over the moon. Sachin,a corporate executive who saw the phenomenon,said,“It was wonderful — at one point,the colour of the moon was red; it was not blue.”

So why does blue moon happen? Devgun explained: “Usually,there’s only one full moon each month because the monthly calendar was built on the lunar

cycle (29.5 days). But once every two-and-a-half years,those extra half days add up to two full moons in a month.” The partial eclipse on the blue moon is rarer still — experts say the last blue moon partial eclipse occurred in December 1982.

The partial lunar eclipse was visible over most of Asia,Australasia,Europe,and Africa. It was visible in the region covering Alaska,Australia,Indonesia,Asia,Africa,Europe,a spokesperson from SPACE said.

A report in the Christian Science Monitor said,“It’s relatively rare that a blue moon would fall on New Year’s Eve. The last time that happened was 1990. Even more rare — there were two blue moons in 1999,one in January and one in March. That happens only about four times a century.”

For enthusiasts,there is good news. The largest moon of 2010 will be witnessed on January 30. Sachin Bahmba,general secretary of SPACE,said: “In 2010,this moon will be the largest moon. People should go out on January 30 and enjoy the night sky.”

On a lighter note he added: “It is perfect for setting up dates.”