Ajay & Neelam Talwar, Nilesh Vayada, Sneh Kesari, Raghu Kalra & Deepak Dogra Arjune & Nakul report from India (group photo):
Location, Location Location, an old quote by William Dillard refers to the three things you should look for when buying a property, building a hotel etc. The quote is very pertinent for solar eclipses too, and capturing the maximum number of Baily's Beads.
The Annular Solar Eclipse of 15th January 2010, the longest Annular of the third Millennium. It is a record holder eclipse BUT this eclipse has been referred to as a glorified partial eclipse, or a central partial eclipse. As compared the to multifarious events happening in a Total Solar Eclipse, nothing dramatic was going to happen in this eclipse. The Moon would pass in front of the Sun slowly and quietly not making much of a fuss.
India has not seen an Annular since 1965, 44 years. Amateurs Astronomers across India thought of going to Rameshwaram, Kanya Kumari and Thiruvananthapuram to photograph the eclipse JFR. (Just for the record) with filters safely on the instruments throughout the eclipse.
Some of us thought that precise location of the observation site could increase the excitement and make this mundane eclipse a more dramatic one. Using Occult software we simulated the bead formation from several places just inside the northern limit of the anti umbral path. In fact someone observing from the northern edge or even 3 kms inside the northern edge would have ended up seeing a partial eclipse because of the presence of a high lunar mountain. It did help a lot that Occult software was updated with Kaguya Satellite - Lunar Data just before the eclipse.
We ended up selecting Varkala, Kerala as our observing spot. Some of the reasons of finalizing Varkala were:
1. There is a 25 meter high cliff at Varkala, next to the sea beach.
2. Plenty of hotels, from cheap to expensive to select from, and with open terraces, being a tourist village.
3. We can see the sea and capture the time lapse sequence over the sea horizon
4. Plenty of beads to be seen from this location on 2nd contact as well as 3rd contact, with about a minute of annularity in between.
5. Bead formation would be slow and steady, giving us enough time to capture.
6. Chromosphere can be seen here at leisure, not just as a moment's flash
7. We thought we might photograph inner corona if the sky happens to be exceptionally clear (absence of scattering of sunlight by haze, clouds, dust etc.)
8. IF THERE ARE any prominences on the same place where contacts are occurring.......
We hit base on all counts except corona, as there was slight haze and humidity scattered all over the sky, making it whitish blue, instead of deep blue.
We also boldly thought that removing the filter was also an option if:
1. If we use a very long focal length, thereby reducing the field of view.
2. If we have a large focal ratio to reduce the intensity of the sun so that no equipment burns.
3. If we use a DSLR camera with a mirror inside to send the light away from the camera shutter.
4. If we do not look through the finder.
This was the instrument train used to capture Baily's Beads and Corona without a filter.
1. Meade 8" SCT, f/10, f.l. 2000mm, Altazimuth mount precisely aligned with Zenith
2. Diagonal Mirror 2" dia
3. 2X Televue Powermate 2" dia, f/20, f.l. 4000mm
4. Canon 450D fov = 19" X 13", approx 2/3 of Sun on the larger side
5. DSLR connected to laptop running Eclipse Orchestrator
6. Pointing to the correct part of the sun made possible with a webcamera attached to 400mm telescope piggybacked on the same telescope, aligned perfectly with the main telescope.
Some of the results are here. The album will be complete in a day or two. The album has been made to look like a presentation, with the setup photo and subsequently the result, with video linked elsewhere (on youtube)
The videos are here
1. Scattered eclipse moving across the sky:
2. A video made out of photographs taken with a 400mm Nikon D90, which was briefly removed off the filter
3. A real time video shot with a webcamera and 400mm telescope containing time beeps as well as the ambient sounds during the eclipse is here
Hope you like the results of our rehearsals and efforts during this Indian Annular. |