=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- От: David Dunham Кому: planoccult@aula.com Написано: 06 февраля 2007 г., 18:51:02 Тема: [PLANOCCULT] Strange (146) Lucina occultation observation --====----====----====----====---- Date: Tue, 06 Feb 2007 00:27:51 -1200 From: Graham Blow To: PETER ANDERSON CC: John Broughton, "Talbot, John (Occ)", "Dunham, David (Home)" Subject: Re: 146 Lucina - a wierdo? Hi Peter, >Dear Graham and John, > I just don't know what happened > here. I was perfectly sober, not drunk and not tired. I was > relaxed and attentive. I had cut my planned monitoring time down to > five minutes to ensure that I was fully alert at the critical > time. Before and after the critical times the image behaved > perfectly normally. I did expect that nothing would have occurred - > as usual for me - just another near miss, but it was wierd. See > report. Do we have a double star and a binary asteroid? Do we have > a rubble pile??? Is there an interstellar invasion fleet lurking > around this asteroid??? Should I keep taking the medication and > increase my dose???? > >Regards, > >Peter A. Thanks for this; this is an important observation as Lucina was alreday known as a suspected binary. See following text from IAUC 3692 - 1982 April 30: ----------------------------------------------------------------- OCCULTATION BY (146) LUCINA J. Lecacheux, Meudon Observatory, reports that the predicted occultation of AGK3 +17 1309 by (146) Lucina on Apr. 18 (cf. BAA Hbk. for 1982, p. 27) was successfully observed at CFRGA's Calern station, near Grasse. A full-amplitude extinction of duration 5s.5 was recorded photoelectrically by M. Froeschle and J. F. Mangin with the 1.5-m reflector; the extinction, which was probably due to a grazing occultation by the minor planet, began at 20h25m03s.2 UT. At Meudon, a possible secondary occultation was recorded by J.-E. Arlot, C. Richardson and W. Thuillot on video tape, using an SIT-vidicon and the 1-m reflector; this full-amplitude extinction, of duration 0s.6 was centered at 20h23m25s UT. No occultation was detected at the Bordeaux Observatory, Floirac, where G. Dourneau was monitoring the star photoelectrically with the 0.6-m reflector. P. Maley, Houston, Texas, also reports that his visual observations from the vicinity of Lyons showed no occultation. ----------------------------------------------------------------- In terms of interpretation though, your observation is not consistent with an occultation by a single secondary body - it's more consistent with a double asteroid occulting a double star. There is a precedent for this - I believe the Kalliope/Linus occ of last November also involved a close double star: http://iota.jhuapl.edu/mp022.htm Cheers, Graham >------------------------------------------------------------------------ > ROYAL ASTRONOMICAL SOCIETY OF NEW ZEALAND OCCULTATION SECTION > MINOR PLANET OCCULTATION EMAIL REPORT FORM > (View this form in a non-proportional font - e.g. Courier 10pt) >Planet (Number and Name for MPs) : 146 Lucina >Star Name : TYC 4681-02401-1 >Date (U.T.) : 2007 Feb 06 >Predicted Time (U.T.) : 10h 41.8m UT >Observer's Name : Peter Anderson >Telephone (include city code) : 61 7 3300 6767 >Postal Address : 53 Highwood Road, THE GAP Q'ld. AUSTRALIA > : >E-mail Address : p.e.anderson@uq.connect.net >TELESCOPE DETAILS: >Aperture (cm) : 41 >Focal length (cm) : 245 >Type (e.g. SCT; Newtonian) : Newtonian >Magnification : X 198 >Observing site name : Taylor Range Observatory >Longitude (East +ve) : 152 56 01.4580 Latitude (South >-ve) : -27 27 47.5562 >Deflection of the Vertical Meridian: -5.271 Prime Vertical: 3.189 >Please note that this astronomical position has been determined by >Qld Dept of Natural Resources and is consistent with the Geodetic >Datum of Australia (GDA94). The physical position of the station has >not shifted since establishment in 1980. >(To find the position of the observatory under various datums, refer >to my website www.uq.net.au/~zzpeande and reference the article 'The >problem of Position' under 'Articles'.) > >Height above Sea level (metres) : 176.3 >Sky Transparency (Delete two) : Fair >Star Image Stability (Delete two): Fair >Other Conditions: > (Wind, Clouds, Lights, etc.): Hazy bright conditions - but no > cloud and no wind. >TIMINGS: (PLEASE REPORT IN UNIVERSAL TIME) >Time Source (e.g. WWVH, VNG) : WWVH >Recording method (e.g. tape) : Stopwatches and tape recorder >Could you see the Asteroid? : Only suspected before event >Approx. Limiting Magnitude : 14.3 > | Estimated | > Universal Time | Reaction | Accuracy, Remarks > h m s | Time (sec) | COLUMN > FORMAT TO USE---> __:__:__._ _._ _________________) >Started Observing : 10 41 00.0 >Star and Object Merged : >Disappearance At : See text >Estimated Closest Approach : (if no D/R) >Reappearance At : Star and Object Separated : Stopped >Observing : 10 46 00.0 >Was your reaction time (also known as Personal Equation) subtracted >from any of the above timings? : If YES, state value : If >you could tell, in which direction did the asteroid pass relative to >the star (Delete three) : NORTH, SOUTH, EAST, or WEST >If possible, estimate the DISTANCE OF CLOSEST APPROACH in arc seconds: >List all Interruptions to Observing: NIL >(FORMAT --> __:__:__._ - __:__:__ _____________________) > FROM TO REASON > Break 1: Break 2: >ADDITIONAL COMMENTS: This would have to be the wierdest asteroidal >occultation I have ever observed. >The image behaved normally and predictably before 10hrs 43min 08sec >and after 10hrs 43min 49sec. I had the impression at the time of >the events that the image was not as 'tight' but this could simply >have been that I was straining. >There were no visible clouds or other apparent reason for the >strange behaviour. > >The sequence of events reconstructed from taped comments and stopwatch: >10hrs 43min 08.0sec (+/- 0.5 sec) possible quick blink >10hrs 43min 09.0sec (+/- 0.3sec) quick blink (These two may be >atmospheric events but I didn't any see others.) >Centered on 10hrs 43min 19.5 sec (+/- 0.5sec) star appeared much >fainter for about 1.0 seconds (maybe even 1.5 sec.) before disappearance. >10hrs 43min 20.30sec (less 0.3secs) = 10hrs 43min 20.0sec STOPWATCH >Star disappeared leaving mv 14.0 asteroid very faintly seen >Star appeared not totally extinguished. It was only fully 'out' for >about 2 seconds after the initial disappearance - strange >10hrs 43min 28.23 (less 0.43sec)= 10hrs 43min 27.8sec STOPWATCH Star >suddenly'back'but not to full brightness - still faint >10hrs 43min 39.5sec (+/- 0.5sec) suddenly back to full brightness >Star very quickly was suddenly faint again >10hrs 43min 48.5sec (+/- 0.5sec) star back again suddenly to normal >brightness. >Then nothing happened..... >_______________________________________________________________________ >Please send this form as soon as possible to: Graham.Blow@actrix.gen.nz >or: RASNZ Occultation Section / P.O. Box 2241 / Wellington / NEW ZEALAND And Peter also wrote: Dear Graham, I am sitting here virtually doubting my sanity, the event was so unusual. I remember some years ago a small spider gor into the eyepiece at the focal plane and I observed a brief ,very close (heh heh) occultation of the star, but I twigged to this immediately because of its nature. In this case all the events occurred around the predicted time with absolutely nothing before and after. I have examined the telescope eyepiece and apart from a few tiny dust specs (not near the focal plane), it is clear, as is the lightpath of the telescope itself. I would therefore rule out the instrument, and I would tend to rule out the observer. (I'm not on any medication - perhaps I should be!) This was a series of events over 41 seconds with nothing before and after and the sky in this area was clear. I would tend to rule out the atmosphere. So something happened, but what? Perhaps John Broughton caught something unusual also... Regards, Peter A. ------------------------------------------ Graham Blow Photography 2003 & 2004 NZ Motorsport Photographer of the Year Motorsport + Landscape Specialist P.O.Box 2241 Wellington, 6140 New Zealand Ph/Fax: +64-4-479-2504 Cell: 025-479-403 Email: graham@grahamblow.com WEB: Photography: http://www.grahamblow.com/ Astronomy: http://occsec.wellington.net.nz/ ------------------------------------------