Return-Path: rwest@eso.org Return-Path: Received: from opus1 (localhost [127.0.0.1]) by opus1.hq.eso.org (8.7.3/eso_cl_6.0) with SMTP id SAA07483; Thu, 14 Nov 1996 18:25:45 +0100 (MET) Message-Id: <199611141725.SAA07483@opus1.hq.eso.org> To: rwest@eso.org, fcomeron@eso.org Subject: P-11 Date: Thu, 14 Nov 1996 18:25:44 +0100 From: Richard West (ESO-Garching; Tel: +4989-32006-276) ------- Forwarded Message Return-Path: bakos@cs.elte.hu Return-Path: Received: from labor1.cs.elte.hu (labor1 [157.181.6.117]) by konig.elte.hu (8.7.5/8.7.3/6s) with ESMTP id RAA03209 for ; Thu, 14 Nov 1996 17:53:08 +0100 Received: from localhost (bakos@localhost) by labor1.cs.elte.hu (8.7.5/8.7.3/4c) with SMTP id RAA00984 for ; Thu, 14 Nov 1996 17:54:55 +0100 X-Authentication-Warning: labor1.cs.elte.hu: bakos owned process doing -bs Date: Thu, 14 Nov 1996 17:54:55 +0100 (MET) From: Gaspar Bakos To: rwest@eso.org Subject: proposal Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Bakos Gaspar Kutvolgyi ut 73/b h-1121, Budapest Hungary bakos@cs.elte.hu bakbubu@ludens.elte.hu - ----- Included text ----- Dear Comittee, I am enclosing our observational proposal: Title: The rediscovery of Comet D/1978 C2 Abstract: Comet D/1978 C2 (Tritton) was discovered by Kenneth Tritton, on the 11th of February, 1978, with the 1.2 meter telescope of Siding Spring Observatory. The comet was extremely faint, and last time it was observed was on the 14th of March, 1978. Thus, all the computations of the orbital parameters are uncertain, with a T(orbital) of approximately 6.35 years. Since its last observation in 1978, the comet has remained unvisible, though it must have reached its perihelion two times. This November is the best period for finding it between its discovery and 2010, its next perihelion of significant elongation. We computed the critical zone of the comet's reoccurence, which would need further investigation. Submitted by: Helix Submitted to: Brorfelde Schmidt Telescope Positions: Due to the complex task they are given in a detailed form in the list of exposures. Magnitude: 16m-17m, expected by ICQ (cf. scientific rationale) List of exposures: Because the comet is moving and its position have some uncertainty we computed the list of the beginning of the exposures for five days; 1996.11.18,1 UT, 1996.11.19,1 UT, 1996.11.20,1 UT, 1996.11.21,1 UT, 1996.11.22,1 UT. Since we can't foretell what day will suit for the exposures (this depends on the weather and the proposals of other groups), we enclose data for all the five days. The coordinates represent the center of the field. Of course, we would need only one night out of the following ones. For more detail please study the scientific rationale and the comments. 1996.11.18,1 UT 1. 4 minutes without filter 09h09,9m +22o37' 2. " " 09 11,4 +22 24 3. " " 09 12,9 +22 11 4. " " 09 14,4 +21 57 5. " " 09 15,9 +21 44 6. " " 09 17,4 +21 31 7. " " 09 18,9 +21 17 8. " " 09 20,4 +21 04 9. " " 09 21,9 +20 50 10. " " 09 23,4 +20 37 11. " " 09 24,9 +20 23 12. " " 09 26,4 +20 09 13. " " 09 27,9 +19 55 14. " " 09 29,4 +19 42 15. " " 09 30,9 +19 28 16. " " 09 32,4 +19 15 17. " " 09 33,9 +19 01 18. " " 09 35,4 +18 48 19. " " 09 36,9 +18 34 20. " " 09 38,4 +18 21 21. " " 09 39,9 +18 07 22. " " 09 41,4 +17 54 23. " " 09 42,9 +17 40 24. " " 09 44,4 +17 27 25. " " 09 45,9 +17 14 26. " " 09 47,4 +17 00 27. " " 09 48,9 +16 47 28. " " 09 50,4 +16 33 29. " " 09 51,9 +16 20 30. " " 09 53,4 +16 06 31. " " 09 54,9 +15 53 32. " " 09 56,4 +15 40 33. " " 09 57,9 +15 27 34. " " 09 59,4 +15 14 35. " " 10 00,9 +15 01 36. " " 10 02,4 +14 48 1996.11.19,1 UT 1. 4 minutes without filter 09h12,9m +22o16' 2. " " 09 14,4 +22 03 3. " " 09 15,9 +21 50 4. " " 09 17,4 +21 38 5. " " 09 18,9 +21 25 6. " " 09 20,4 +21 12 7. " " 09 21,9 +20 58 8. " " 09 23,4 +20 45 9. " " 09 24,9 +20 32 10. " " 09 26,4 +20 18 11. " " 09 27,9 +20 05 12. " " 09 29,4 +19 52 13. " " 09 30,9 +19 38 14. " " 09 32,4 +19 25 15. " " 09 33,9 +19 12 16. " " 09 35,4 +18 59 17. " " 09 36,9 +18 45 18. " " 09 38,4 +18 33 19. " " 09 39,9 +18 19 20. " " 09 41,4 +18 06 21. " " 09 42,9 +17 51 22. " " 09 44,4 +17 37 23. " " 09 45,9 +17 24 24. " " 09 47,4 +17 09 25. " " 09 48,9 +16 55 26. " " 09 50,4 +16 41 27. " " 09 51,9 +16 27 28. " " 09 53,4 +16 13 29. " " 09 54,9 +15 59 30. " " 09 56,4 +15 46 31. " " 09 57,9 +15 32 32. " " 09 59,4 +15 18 33. " " 10 00,9 +15 05 34. " " 10 02,4 +14 51 35. " " 10 03,7 +14 37 36. " " 10 05,2 +14 23 1996.11.20,1 UT 1. 4 minutes without filter 09h14,4m +22o05' 2. " " 09 15,9 +21 52 3. " " 09 17,4 +21 40 4. " " 09 18,9 +21 26 5. " " 09 20,4 +21 13 6. " " 09 21,9 +20 59 7. " " 09 23,4 +20 46 8. " " 09 24,9 +20 32 9. " " 09 26,4 +20 18 10. " " 09 27,9 +20 03 11. " " 09 29,4 +19 50 12. " " 09 30,9 +19 36 13. " " 09 32,4 +19 23 14. " " 09 33,9 +19 09 15. " " 09 35,4 +18 56 16. " " 09 36,9 +18 43 17. " " 09 38,4 +18 30 18. " " 09 39,9 +18 16 19. " " 09 41,4 +18 03 20. " " 09 42,9 +17 49 21. " " 09 44,4 +17 37 22. " " 09 45,9 +17 24 23. " " 09 47,4 +17 10 24. " " 09 48,9 +16 57 25. " " 09 50,4 +16 43 26. " " 09 51,9 +16 28 27. " " 09 53,4 +16 15 28. " " 09 54,9 +16 01 29. " " 09 56,4 +15 48 30. " " 09 57,9 +15 35 31. " " 09 59,4 +15 22 32. " " 10 00,9 +15 08 33. " " 10 02,4 +14 54 34. " " 10 03,7 +14 40 35. " " 10 05,2 +14 26 36. " " 10 06,7 +14 12 1996.11.21,1 UT 1. 4 minutes without filter 09 17,4 +21 43 2. " " 09 18,9 +21 31 3. " " 09 20,4 +21 18 4. " " 09 21,9 +21 04 5. " " 09 23,4 +20 51 6. " " 09 24,9 +20 38 7. " " 09 26,4 +20 24 8. " " 09 27,9 +20 11 9. " " 09 29,4 +19 58 10. " " 09 30,9 +19 44 11. " " 09 32,4 +19 31 12. " " 09 33,9 +19 17 13. " " 09 35,4 +19 04 14. " " 09 36,9 +18 50 15. " " 09 38,4 +18 37 16. " " 09 39,9 +18 24 17. " " 09 41,4 +18 11 18. " " 09 42,9 +17 57 19. " " 09 44,4 +17 43 20. " " 09 45,9 +17 30 21. " " 09 47,4 +17 16 22. " " 09 48,9 +17 02 23. " " 09 50,4 +16 48 24. " " 09 51,9 +16 34 25. " " 09 53,4 +16 20 26. " " 09 54,9 +16 06 27. " " 09 56,4 +15 52 28. " " 09 57,9 +15 38 29. " " 09 59,4 +15 24 30. " " 10 00,9 +15 11 31. " " 10 02,4 +14 57 32. " " 10 03,7 +14 43 33. " " 10 05,2 +14 29 34. " " 10 06,7 +14 15 35. " " 10 08,2 +14 00 36. " " 10 09,7 +13 46 1996.11.22,1 UT 1. 4 minutes without filter 09 18,9 +21o34' 2. " " 09 20,4 +21 20 3. " " 09 21,9 +21 06 4. " " 09 23,4 +20 53 5. " " 09 24,9 +20 40 6. " " 09 26,4 +20 26 7. " " 09 27,9 +20 12 8. " " 09 29,4 +19 58 9. " " 09 30,9 +19 46 10. " " 09 32,4 +19 34 11. " " 09 33,9 +19 20 12. " " 09 35,4 +19 08 13. " " 09 36,9 +18 55 14. " " 09 38,4 +18 42 15. " " 09 39,9 +18 28 16. " " 09 41,4 +18 14 17. " " 09 42,9 +18 00 18. " " 09 44,4 +17 47 19. " " 09 45,9 +17 34 20. " " 09 47,4 +17 20 21. " " 09 48,9 +17 06 22. " " 09 50,4 +16 52 23. " " 09 51,9 +16 39 24. " " 09 53,4 +16 23 25. " " 09 54,9 +16 08 26. " " 09 56,4 +15 54 27. " " 09 57,9 +15 41 28. " " 09 59,4 +15 26 29. " " 10 00,9 +15 11 30. " " 10 02,4 +14 57 31. " " 10 03,7 +14 44 32. " " 10 05,2 +14 30 33. " " 10 06,7 +14 16 34. " " 10 08,2 +13 02 35. " " 10 09,7 +13 48 36. " " 10 11,2 +13 34 The scientific rationale: The rediscovery of Comet D/1978 C2 (Tritton) Comet D/1978 C2 (Tritton) was discovered on a photograph of Siding Spring Observatory's 1.2 meter Schmidt telescope by Kenneth Tritton, on the 11th of February, 1978. The integrated magnitude of the object was only V = 20m, thus its last observation occurred shortly after its discovery, on the 14th of March, 1978. According to the computations of Brian G. Marsden, the comet turned out to have a short period, with T(orbital)= 6.35 years. At the time of its next return, in 1984, the comet remained mysteriously invisible. In 1990, at the time of its second perihelion, the comets projected position was extremely close to the sun's, so there was no chance of tracking it down. Since its original discovery it hasn't been in such an advantageous position. The elongation of the comet Tritton is approximately 95 deg, the time of its perihelion was in the beginning of November, so it is likely to reach its maximum brightness at the proposed time of observation. The next perihelion, in 2003, won't be suitable for finding the comet, due to its small elongation. Altogether, this year, and especially this part of November, is the best time for checking the perplexities arising around the existence of Comet Tritton. Concerning the details, the orbital parameters of the comet computed by Daniel W. Green were published in the International Comet Quarterly (ICQ) 1996 Comet Handbook, however it was clearly stated that the expected time of perihelion is only known within an absolute error of +/-10 days.Thus, the position of the comet can be only limited by a stripe-shaped area of the sky (approx 14 deg. long). The orbital parameters: T = 1996. 11. 05,0126 TT (decimals!) Peri.= 147.5852 deg q = 1,436362 AU Node = 300.7139 deg e = 0,580612 i =7.0491 deg In order to determine the ephemerides for the object between the 18th an 22nd of November we assumed several values for the time of perihelion (Tas). These values start at 1996.10.26,0126 TT with steps of two days interval. The numerical computations were carried out by the software Deep. Tas 96.11.18,2 UT 96.11.19,2 UT 11.26. 10h02,8m 14o43' 10h05,1m 14o24' 11.28. 09 58,4 15 24 10 00,7 15 06 11.30. 09 53,9 16 07 09 56,1 15 49 12.01. 09 49,1 16 51 09 51,4 16 33 12.03. 09 44,1 17 37 09 46,4 17 19 12.05. 09 38,9 18 24 09 41,3 18 06 12.07. 09 33,5 19 12 09 35,8 18 55 12.09. 09 27,8 20 03 09 30,2 19 45 12.11. 09 21,9 20 54 09 24,2 20 38 12.13. 09 15,6 21 48 09 17,9 21 31 12.15. 09 09,0 22 43 09 11,3 22 27 Tas 96.11.20,2 UT 96.11.21,2 UT 11.26. 10h07,3m 14o06' 10h09,5m 13o48' 11.28. 10 02,9 14 48 10 05,1 14 29 11.30. 09 58,4 15 31 10 00,6 15 12 12.01. 09 53,6 16 15 09 55,9 15 57 12.03. 09 48,7 17 01 09 50,9 16 43 12.05. 09 43,5 17 48 09 45,8 17 31 12.07. 09 38,1 18 37 09 40,4 18 20 12.09. 09 32,5 19 28 09 34,7 19 11 12.11. 09 26,5 20 21 09 28,8 20 04 12.13. 09 20,2 21 15 09 22,5 20 58 12.15. 09 13,6 22 11 09 15,9 21 55 Tas 96.11.22,2 UT 11.26. 10h11,6m 13o29' 11.28. 10 07,3 14 11 11.30. 10 02,8 14 54 12.01. 09 58,1 15 39 12.03. 09 53,1 16 25 12.05. 09 48,0 17 13 12.07. 09 42,6 18 02 12.09. 09 37,0 18 53 12.11. 09 31,0 19 46 12.13. 09 24,8 20 41 12.15. 09 18,2 21 38 The length of the critical zone that needs inspection can be derived from the data, and it turns out to be 14 degrees. Such a big area calls forth an instrument with wide field of view. The Schmidt telescope of Brorfelde is suitable for this task; the zone could be covered by 36 exposures. with an overlap of three arcseconds on both sides of the frames. The time of the discovery of D/1978 C2 was five months later than its perihelion, so the brightness profiles for the comet are totally unknown. Again, according to the ICQ 1996 Comet Handbook, an estimated brightness of the 16th-17th magnitude seems to be probable, which means in our case exposure times of at least 4 minutes, without filters. Since it might happen that the time limits our programme, it can be carried out in a shorter, but not so effective version. This would mean a smaller number of exposures, covering the middle of the zone symmetrically (around frame no.18, for example from frame ), but involving a smaller likelihood of finding the comet. For the reduction of the observations, and for excluding other objects than Comet Tritton, we would use POSS, NED, SIMBAD and some other powerful sources now available via internet. For the data analysis of the images we can use IRAF and/or MIDAS. In case of any discovery we would immediately contact the Central Bureau of Astronomical Telegrams (CBAT). If we happen to find Comet Tritton, we might ask for an extra exposure, so as to find out more detail about the object and its movement. It would be essential to follow the route of the comet, in order to determine its more precise orbital parameters. If we have a frame that contains the image of the comet, we can determine the approximate time of its perihelion, so we can find it in the followwing week. We would also like to identify some of the minor planets that are visible on the exposures. This could be simply done by the combination of the software of CBAT (identification of minor planets), and POSS. Comments: If we consider that the beginning of the 36-element-series of exposures is at 0.1 UT each day, and one exposure takes four minutes, than this means 4*36= 144 minutes= 2h 24m netto time. We assumed maximum one minute for the setting of the telescope to the new position, because it is quite close to the previous one. Altogether, the observational time is three hours, so it ends in the very beginning of astronomical dawn. If longer time is needed between the exposures, the end of the programme might run into the zone of half-darkness. In this case we would suggest that the programme should be cut into two parts, and continued in the following day's night. Place and date of submission: Budapest, 14th of November,1996 Yours sincerely: Gaspar Bakos group leader ------- End of Forwarded Message