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--Apple-Mail-1--225839260 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Hello everyone: I just finished scanning three of the sketches that I made of Comet Holmes over the last two weeks and have posted a collage on my web site. The "texturing" is caused my the scanner doing too good a job on the rough paper, and there is a bit of bleed through showing up from the sketch/text on the other side the paper, again due to the scanning process. http://myweb.dal.ca/pmkelly/Holmes_Collage.jpg All three sketches were made with the same telescope (25-cm) Newtonian telescope, and with the same eyepiece. Thus all sketches take in the same apparent field of about half a degree (the apparent size of the Full Moon). Given that, one can see that the comet has grown considerably in size over that period of time. Note that on Oct. 31, the comet was evenly "crisp" all the way around. The next night it was noticably soft and "fuzzy" along the left-hand side. David Lane took an image of the comet at about the same time and you can see that this is where the tail is starting to form. I have indicated a few star patterns that are in both the sketch and the CCD image. I know that I got them all in the right positions, so I'm not sure what the problem is with Dave's camera! :) Note as well, that with a long exposure, there is a broad band that does not show up visually. It was so faint that it required really dark skies, and while Falmouth does not have a lot f light pollution, the comet was in the "glow" from nearby Windsor. The same is also true of the tail, it is really faint... It has also been noted that the expansion of the comet has been linear, with its size increasing at a constant rate after the initial outflow of material. I recally that at the Minas Astronomy Group meeting, Roy Bishop mentioned the actual expansion speed as something like 2000 km/h. The coma (the bright spherical region) has grown in size until it how occupies a spherical volume of space that is larger than the Moon's orbit around the Earth, and approaching the volume of the Sun. And all of this from a piece of dirty ice that is only a few kilometres across. No wonder the one astronomy once referred to a comet as nothing more that a prolonged cosmic fart! While the comet was much larger last night, it was also noticeably fainter with the unaided eye, and given the Moon is coming around again and the bad weather, you might want to see it while you still can. Pat ======================================================================== == Patrick Kelly Director of Computer Facilities ======================================================================== == Faculty of Architecture and Planning Dalhousie University ======================================================================== == PO Box 1000 Stn Central 5410 Spring Garden Road Halifax, Nova Scotia B3J 2X4 Halifax, Nova Scotia B3J 2X4 Canada Canada ======================================================================== == Phone:(902) 494-3294 FAX:(902) 423-6672 E-mail:patrick.kelly@dal.ca ======================================================================== == --Apple-Mail-1--225839260 Content-Transfer-Encoding: 7bit Content-Type: text/enriched; charset=US-ASCII Hello everyone: I just finished scanning three of the sketches that I made of Comet Holmes over the last two weeks and have posted a collage on my web site. The "texturing" is caused my the scanner doing too good a job on the rough paper, and there is a bit of bleed through showing up from the sketch/text on the other side the paper, again due to the scanning process. http://myweb.dal.ca/pmkelly/Holmes_Collage.jpg All three sketches were made with the same telescope (25-cm) Newtonian telescope, and with the same eyepiece. Thus all sketches take in the same apparent field of about half a degree (the apparent size of the Full Moon). Given that, one can see that the comet has grown considerably in size over that period of time. Note that on Oct. 31, the comet was evenly "crisp" all the way around. The next night it was noticably soft and "fuzzy" along the left-hand side. David Lane took an image of the comet at about the same time and you can see that this is where the tail is starting to form. I have indicated a few star patterns that are in both the sketch and the CCD image. I know that I got them all in the right positions, so I'm not sure what the problem is with Dave's camera! :) Note as well, that with a long exposure, there is a broad band that does not show up visually. It was so faint that it required really dark skies, and while Falmouth does not have a lot f light pollution, the comet was in the "glow" from nearby Windsor. The same is also true of the tail, it is really faint... It has also been noted that the expansion of the comet has been linear, with its size increasing at a constant rate after the initial outflow of material. I recally that at the Minas Astronomy Group meeting, Roy Bishop mentioned the actual expansion speed as something like 2000 km/h. The coma (the bright spherical region) has grown in size until it how occupies a spherical volume of space that is larger than the Moon's orbit around the Earth, and approaching the volume of the Sun. And all of this from a piece of dirty ice that is only a few kilometres across. No wonder the one astronomy once referred to a comet as nothing more that a prolonged cosmic fart! While the comet was much larger last night, it was also noticeably fainter with the unaided eye, and given the Moon is coming around again and the bad weather, you might want to see it while you still can. Pat <fontfamily><param>Courier</param> ========================================================================== Patrick Kelly Director of Computer Facilities ========================================================================== Faculty of Architecture and Planning Dalhousie University ========================================================================== PO Box 1000 Stn Central 5410 Spring Garden Road Halifax, Nova Scotia B3J 2X4 Halifax, Nova Scotia B3J 2X4 Canada Canada ========================================================================== Phone:(902) 494-3294 FAX:(902) 423-6672 E-mail:patrick.kelly@dal.ca ========================================================================== </fontfamily> --Apple-Mail-1--225839260--
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