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Quest for Venus in the daytime, from the Jantar Mantar

It all started with Arvind Paranjpye's post in the group

about the close positioning of Moon and Venus late in January 2009 and the easy possibility for people to locate Venus in daytime, using that fact.

Well, one thought was the following (also discussed in the yahoogroup) -

For the Delhi wallahs (or Jaipur wallahs), a thrilling way of locating Venus in the daytime is to take a printout of its altitude and azimuth for every minute and then go to the Ram Yantra and station oneself at the appropriate position w.r.t. the Altitude and Azimuth and look against the centre of the gnomon - it should definitely work - provided there is some blue in the sky. On any day when Venus is far enough away from the Sun and there is blue in the sky - one should try this.

Well, we did try this, on the 1st of February 2009. Venus had moved a little away from the Moon. We did have the Altitude and Azimuth data for Venus, for every minute of the afternoon, from the NASA Horizon's site (with standard refraction correction).

(See here Ram Yantra Usage for information on the method of measuring Altitude and Azimuth of celestial objects with the Ram Yantra)

Ruhi and Bhavna were there with us, right from the morning, patiently working on collecting time measurements with the Misra Yantra. Megha, Riddhi and CB joined in soon. When Sneh walked into the Jantar Mantar compound, he was hailed by Megha as the chalta phirta Ram Yantra. Well, so he is.

There was not that much of blue in the sky during the afternoon. The altitude of Venus at this time, was also more than 45 degrees, which meant that one had to crouch on the floor and keep the eye level with the floor sectors of the Ram Yantra, in order to be at the correct position w.r.t. the altitude. Many of us at the Jantar Mantar on that day, tried it. Most did not see it - two of us did think very strongly that yes, we did see Venus somewhere close to the position indicated.

CB helping Sneh to position himself at the correct Azimuth. The Altitude positioning was already completed. Well, neither of them, when they tried this method of viewing, felt that they had seen Venus. Jasmeet, standing closer to the wall, well away from the correct position, did some scanning of the sky too.

Well, I did. Feel very strongly, that yes, I could see it, after moving my head a little away from the correct position and looking well above the centre of the gnomon. I think, both Megha and Riddhi, tried looking for Venus from many locations other than the correct one. Ruhi, did view from the correct location and felt that she had seen it too.

Well, most of the AAAD members had to leave for the planetarium soon. And then at 20 minutes past 4, the relevant segment of the sky turned Oh so Blue!

Well, we could not share the wonderfully soft muted white and beautiful view of Venus that could be located easily without the help of Ram Yantra, with the AAAD members, but, one of the Jantar Mantar staff and us from the Plani, enjoyed this view.

We just let the Sun be hidden by the wall of the Misra Yantra and scanned the regions from the Moon towards the Sun and there it was a subdued but beautiful and unmistakable speck of white against the painfully beautiful blue of the sky.

This image does not show Venus, although it is definitely there in this field of view.

Some fiddling with the camera settings (and a little cheating, as this image was taken when the Sun was almost setting) did capture Venus in the daytime sky in this image.

A lucky and thrilling capture was a crow against the Moon :-)

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Page last modified on February 06, 2009, at 10:29 AM EST