ASTEROIDAL OCCULTATION - REPORT FORM (ammended) +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 22 July 2019 STAR: UCAC4 337_192858 ASTEROID: Selene N?: 580 2 OBSERVER: Name: Tim HAYMES Abbr: TVH E-mail: ********* Address: 3 Florence Villas, Bottle Lane, Littlewick Green, SL6 3SA 3 OBSERVING STATION: Nearest city: MAIDENHEAD Station: ** Temporary ** Latitude: N 51 30 **** Longitude:W 00 48 **** Altitude: 63m Datum (WGS84 preferred): WGS84 +----------------------------------+ 4 TIMING OF EVENTS: | | | OCCULTATION RECORDED: POSITIVE | | | +----------------------------------+ Comments Event Time (UT) P.E. Acc. Code HH MM SS.ss S.ss S.ss S - 2214 - - : 0.32s integration (8 frames) D - 2216 36.33 - +/- 0.16 -0.34s correction is applied R - 2216 37.61 - +/- 0.16 E - 2318 - - : Duration : 1.28 Mid-event : 2216 36.97 s 5 TELESCOPE: Type: SCHMIDT NEWT. Aperture: 203mm Magnification: Prime focus F/4 Mount:EQ6 Motor drive: Yes 6 TIMING & RECORDING: Time source: GPSBOXSPRITE2-U Sensor: WATEC 910HX/RC (CCIR, #1106) 1/2 inch 752x582 array (8.6 x 8.3u) Recording: Digital tape: Sony TRV33E DV camcorder (video-in) AVI Time insertion (specify): 1 PPS Event insertion (specify): TANGRA + AOTA analysis. Tangra performed automatic OCR and time calibration of the AVI. No corrections are appied at this point. AOTA analysis with assistance from E Frappa (Thanks Eric) 7 OBSERVING CONDITIONS: Atmospheric transparency: 2/5 Wind: 0-1B Temperature: +18C Star image stability: 3/5 Minor planet visible? : No 8 ADDITIONAL COMMENTS: Star ID GSC 6890-527. My location was just outside the predicted shadow zone. The telescope was moved 3 meters to the East to avoid a tree, but the Long/lat hasnt been adjusted. With a 4 frame integation the target star was effected by seeing conditions at this low altitude of 13 degrees. So I decided to use a longer 8 frame integration to be sure of an event, and sacrifice time resolution. The star was occulted for two full integration periods (2 x 0,32s) Integration : 0.32s (8 frames) Gain (dB) : 38 dB Gamma : 1.0 S/N(Tangra) : 6 Mag limit ~ : 13.5 Predicted Time : 22 Jul; 22:16:30 UT +/- 4 sec Combined Mag : 12.3 Predicted drop : 2.7 Max. Duration : 3 sec OW Centre Dist.: 35 km OW Probability : 28.3% Shaddow Width : 183 km Alt/Az : 13° @156° Moon Alt : -5° Constellation : Sagittarius