TaareWiki | Site / A skywatch for Venus on its way to transit

There is worldwide excitement awaiting the Transit of Venus across the disk of the Sun as will be witnessed on the 5th/6th of June 2012. Well ahead of that, in the coming weeks, the planet Venus will be seen with increasing brightness descending rapidly towards the Sun, and later, slowly disappearing in its glare. Everyone would have had seen Venus at its best these days – dominating the western skies with its dazzling brilliance.

Something a little strange about it, may or may not have been noticed. This strangeness is a recurring phenomenon with Venus, well known since its first discernment by Galileo, who was the first to turn a telescope towards celestial objects. As Venus becomes brighter, through its appearing nearer and nearer to the Earth in its orbit around the Sun, it becomes thinner and thinner – at its brightest, Venus will be just a thin crescent – something which is discernable only when it is viewed through a telescope.

For people interested in the history of astronomy, and in particular from an Indian perspective, it would be quite intriguing to note that there are some possible mentions of phases of Venus in a 17th century treatise on astronomy, in India. This is the Siddhanta Tattva Viveka of Kamalakara, from Varanasi, thought to have been published around 1658. There are several shloka in this treatise where Kamalakara refers to the fact that Venus becomes thinner as it becomes brighter. It would be very fruitful to initiate a closer look at atronomical understanding and observations in the 17th century, from India. (Article by N. Rathnasree, B. S. Shylaja, Geetha Kaidala and Amitabh Mukherjee, submitted to Current Science)

To allow citizens of Delhi a view of the crescent Venus, a skywatch is being organized by the Nehru Planetarium, Nehru Memorial Museum and Library. Some telescopes will be setup at the planetarium on the 4th of May2012, at sunset, and visitors can view not just the planet Venus, but, also Saturn and Mars and the Moon, though these telescopes.

There is a peculiar poignancy attached with observing Venus at this time, knowing the it is journeying on its way to transiting in front of the Sun – a rare occurrence which none of us now alive will see again, as its next occurrence will be in the year 2117.

The planetarium has prepared a special full dome program about the transit of Venus, which can be seen at 11:30 AM, 3:00 PM and 5:00 PM on this day, to be followed by a discussion session in the planetarium sky theater, about the interesting movements of Venus in the sky and in its orbit, around the Sun.