+--------------------------------+ +--------------------------------+ ASTEROIDAL OCCULTATION - REPORT FORM +--------------------------------+ +--------------------------------+ EAON & IOTA-ES EUROPEAN ASTEROIDAL OCCULTATION NETWORK INTERNATIONAL OCCULTATION TIMING ASSOCIATION EUROPEAN SECTION +--------------------------------+ +--------------------------------+ 1. DATE: 14 Nov 2020 STAR: UCAC4 535-013994 ASTEROID: (275) Sapientia 2. OBSERVER Name: Stefano SPOSETTI Address: 6525 GNOSCA - Switzerland Email: stefanosposetti@ticino.com 3. OBSERVING STATION Nearest city: CH-6525 Gnosca Station: 143 (MPC-code) Longitude (DD MM SS.s): 09 01 26.5 (E) Latitude (DD MM SS.s): 46 13 53.2 (N) Altitude: 260 m (WGS84) 4. TIMING OF EVENTS Occultation recorded: POSITIVE Type of event: "S"tart observation; "I"nterrupt-start; "D"isappearance; "B"link; "F"lash; "E"nd observation; "I"nterrupt-end; "R"eappearance; "O"ther (specify) Personal Equation Substracted: - Event Time (UTC) Accuracy + Comments code: HH:MM:SS.ss S.sss -S : 20:59:00 -D : 21:01:52.51 ± 0.02 s -R : 21:02:02.00 ± 0.02 s -E : 21:05:00 Duration: 9.49 s ± 0.04 s 5. TELESCOPE -Type: Newton -Aperture: 420 mm -Focal length: 1640 mm -Mount: Equatorial -Motor drive: Yes 6. TIMING & RECORDING -Camera/Sensor: Videocamera QHY174M-GPS, SONY IMX174 CMOS sensor -Device of recording: personal computer, USB3 input, SharpCap PRO v. 3.2.6173.0 software, saved on SSD as SER file -binning = 2x2, sensor uncooled, camera bit depth = MONO16, area size in pixel = 960x600, USB traffic = 5, setted exposure = 30 ms, gain = 480, offset = 0, contrast = 0, brightness = 0, gamma = 1, banding suppression = 0, banding threshold = 35, apply flat = none, subtract dark = none -Timekeeping: GPS UTC clock -Integration time: 0.030 s 7. OBSERVING CONDITIONS -Atmospheric transparency: good -Wind: none -Star image stability: good -Minor Planet visible during the occultation: barely 8. ADDITIONAL COMMENTS Prediction: -Occultwatcher, IOTA feed -Rank: 100 -Probability: 72.4 % -Combined magnitude: 11.2 mag -Star magnitude: 11.4 mag V -Asteroid magnitude: 13.2 mag -Lightdrop: 2.0 mag -Max duration: 12.1 s -Event time: 21:01:56 UT -Error in time: 4 s -Moon distance: - -Moon illumination: - Other comments: -Target sky position: elevation = 30 deg, azimut = 96 deg -Tangra v. 3.7.3 was used to generate the lightcurve (aperture photometry, average background) -D and R times were evaluated using AOTA v4.10.5.0, applied confidence level: D = 90 %, R = 90 % -Measured mid-event UT time: 21:01:57.3 -Measured lightdrop: from ~ 301500 ADU to ~ 74400 ADU, ie. 1.5 mag -SN at event locations: D: 6.7; R: 4.9; Ave: 5.8 -A lightcurve can be seen here: http://sposetti.ch/wp-content/uploads/2020/11/2020_11_14_Sapientia_Gnosca.png