Observing and Imaging at Kavalur Observatory - 29th January 2009



By amar_universe; Published 10 Mar 2009

7 years later, this was my 6th visit to Kavalur Observatory, a place only 150 km from B'lore, that I have always revered and worshipped. I am overly thankful to two of my mentors, Dr Shylaja (Bangalore Jawaharlal Nehru Planetarium) for making it happen, and Dr Rathnashree (Director, JNP, Delhi) to initiate the idea. This trip happened for the 7 students from the REAP course, JNP and I accompanied them. We were supposed to have the 40-inch telescope for one entire night of imaging some bright Messier objects, and comets. We met at Indian Institute of Astro-Physics (IIAP) head office, Koramangala at 8am and divided ourselves in the shuttle (two Ambassador cars). It was a 3hr drive on the super, clean, empty and broad Hosur-Krishnagiri-Vellore highway (NH-46). The sky was pretty hazy, lowering our chances, and I expected B'lore city itself to have been much clearer then.


We reached Kavalur on time for lunch at around 2. After unloading our luggage in the rooms and having food, we rested until evening. By 5pm we departed for the 40-inch observatory, where there were preparations for an ongoing observation of a variable star. The telescope operators for the 40-inch were Mr Kuppuswamy (co-discoverer of Uranus' rings) and Mr Muneeraj (the same two operators in my last 4-night trip in June 2007). They poured liquid Nitrogen into the 1K x 1K CCD and were busy making preparations. We saw them taking 'skyflat' 'bias frames' and other CCD pre-requisites under still hazy skies. Fingers all crossed, till we get our turn!


Our entire gang gathered by sunset, and witnessed an exquisite sunlight color against the cloudy sky, in the backdrop of the distant 2.3-metre dome. This twilight sky was the sign for an oncoming night we were really blessed for, and really anticipating. The mighty dome opened and the mighty white telescope moved to the target in Monoceros. The sight of the monstrous counter-weight balancing actually above the telescope was a breath-taking one! By now we had begun some observations with the 10x50 binocs in the quite hazy skies, until we departed for dinner in the pitch-black location. All night, we carried on observations from the 360-degree panoramic railings encircling the dome, some 50-feet above ground. Other moments were spent taking refuge in the cozy observatory room. After dinner, I slept from 9:45 to 11:30 pm.


I've only once seen clear skies here on 12th June 2007, when monsoon clouds cleared up. However this time, it being winter, the density of stars was EXCEPTIONAL!! The Canis Major and Carina Milky-Way post-midnight was extremely broad and dense. Zenithal stellar density was very good, could be around mag 6.5. M33 was naked-eyes with averted vision. 3 decades later, local lights here have taken a toll in some directions, making it very bad for an observatory site.


Now about my observations. After showing everyone the basic binocular targets, I moved on to 10x50 limit-testing. I could see Comet 144/P Kushida close to Gamma Taurus, easily as a fuzzy circular spot. NGC 253 (Sculptor galaxy) was visible through pertaining haze, along with it's neighboring globular, NGC 288. I was glad when I could spot a new target, a 9.6 mag barred-spiral galaxy in Fornax, NGC 1365.


At midnight, I could spot M97 with the binocs (yeah Owl Nebula!!) with not much difficulty, since I knew where to look for. While looking for M108 galaxy nearby, M97's view enhanced due to averted vision, however the edge-on galaxy itself was not confirmed. M51 (Whirlpool galaxy) with it's companion NGC 5195 also was easily visible (first time) as two detached objects!


I ventured into the Virgo cluster, since the conditions were inviting. M100 was easier than last time, and I could spot M84 and M86 (which shows conditions were indeed very good). M87 was a fuzzy spot overlapping a star, and hereafter I saw 3 more spots of light which could be Messiers, but I'm not able to confirm.


The other newer targets seen with the binocs were : globulars M68, NGC 5286, NGC 6144 and galaxies M83, Sombrero, Centaurus A with a new open cluster NGC 4103 in Crux. Such eventual observations of faint objects are making me feel more confident with just a 10x50 binocs! I challengingly tried for the faint M109 galaxy in UMa with the binocs, but erred in it's location, confusing with a 10.5 mag star. The binocs were getting fogged time and again.


It was the second time from Kavalur I tested the 10x50 binocs to their limit, hand holding them, seeing more than expected. My streak of comets with the 40-inch also continues for the second time, after last time's rendezvous with Comet LINEAR.


Before proceeding, here's something intimate I want to share. I've ALWAYS maintained a well-to-do give-take relationship with Mother Nature. I have trusted Her even in the worst conditions, and its been paid back for well. We thought we may not get a chance to observe anything after 3am, since if the humidity goes beyond 80% they will shut the dome, which actually happened. Infact, condensed water droplets were constantly dripping on our heads and binoculars, when we were outside on the railings, observing upwards! On the ground there was a pool of water! Very soon, the sky 'could' get all fogged up (as we heard was happening for past few days, once at even 11pm!)


By 2 am the dome was closed, and we had to wait for permissible humidity of 75%; it was now 82% making chances slim, since humidity would only increase with time. I went out for a couple minutes, looked up at the sky and spent a silent moment. Then at 3 am, Mr Muneeraj told me we can start imaging! This was it!! The skies till we ended our session pre-dawn, were CRISP and clear, without any fog, except at horizons.


We started with what else but some...comet. Periodic 29/P Schwassmann-Wachmann-1 was ever in my mind since it had developed a new anti-tail feature. After some discussion regarding it being a faint object for the setup, the operators were kind enough to point the telescope to the location in Gemini. We took two trial exposures to confirm the object in the center of the field. I tried observing the 12th mag comet through the 8" and 4" finder scopes atop the main scope, simply to no avail. The handpad of the big telescope was in my hands! We waited for the image to appear on the computer screen; just as nervous as students are while exam results. There was nothing but noise on the 2 pictures, and we heaved a sigh of utter despair. Only Eskimo Nebula (NGC 2392) was close to this region, and we had to move on for the next image. A single exposure, each in B and V filter was taken, and there it was...that HUGE brightest blob covering a part of the screen!


The skies were as if holding back just for us, it was close to 4:30 am, and hardly any fog and haze in the sky. If it was the bright Comet Lulin, it was NOW. The telescope did take time to drag itself to exactly the opposite direction in Libra. There, in both the finder scopes, we all did see comet Lulin as a big hazy mottled patch, like M13 or M22. Two exposures each in B, V and R filters were taken. We waited to see how this one turns up. Finally, the dead of the night was broken when 3 of us at the computer screen synchronously yelled a long 'Whoooaaaaaaa' looking at the size and brightness of the comet's coma!! It was the biggest thing I have seen, thanks to a 40-inch, but with no detail. We are waiting to process these images at the earliest, and see what they hold in store for us.


Soon after, the skies above the observatory were bid adieu, by the telescope and us. We departed to the rooms, after hearing some music on the radio. Atleast 3 FM radio stations from Bangalore 150 km away were being clearly received here!!!

I did not want to observe anything in the last hour of darkness available. The skies clarity was STILL held on! We left Kavalur in the morning after couple hour's sleep, and breakfast, reaching IIA campus. A trip to remember always...


Some casual pics of the trip are here:


http://picasaweb.google.com/amar10sharma/KavalurObservatory30thJanuary20...