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2025-05-02 / TYC 6334-01601-1 / (1806) Derice

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Michael Kohl O+ VID M200 CH GPS 03:33:43 03:34:12.08 03:34:12.66 03:34:44 0.03 0.05 0.58 8.5
2 show Gregor Krannich O+ VID M350 DE GPS 03:33:39 03:34:24.31 03:34:24.82 03:34:53 0.030 0.040 0.51 7.4
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

2 observations found in db: sodis

Available (probably) matching predictions (click on the link to switch):
JPL#65 : 1c6fbf10-879f-11ef-78cd-df4bbfffabe3 [db: asteroids]

Using prediction 1c6fbf10-879f-11ef-78cd-df4bbfffabe3 for map and profile fit

Get observations as KML file (reduced site location resolution)

Ellipse and circular profile fits to the timings (chords)

 Auto-Fit Result:
X0,Y0 = 2089.7, 23.1 km
Circular diameter = 9 km

From 2 chords (VID)








You can enter space separated chord numbers (example: 11 4 8) or a method like VIS to ignore all visual timings, or a time source like RAD and NTP (but not GPS).
If the plot disappears, then there are less than 2 chords left (too much ignored, go back with browser).

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Map with groundtrack and observer stations

Event Details 
 Occultation UUID [and DB] : 1c6fbf10-879f-11ef-78cd-df4bbfffabe3 [asteroids]

 Occultation Date + Time   : 2025-05-02 at 03:34:01 UT +/- 0.0 min  [1]
 Object Designation        : (1806) Derice
 Orbit Class               : MBA
 Star Designation          : GDR3 6861715038574185600
 Star Coordinates (ICRF)   : RA = 20 37 39.8039, DE = -17 33 23.187  [2]
 Star Magnitudes           : G = 9.6 mag, RP = 8.91 mag, BP = 10.13 mag
 Object Magnitude          : V = 16.87 mag
 Estimated Magnitude Drop  : 7.3 mag
 Estimated Max. Duration   : 0.9 sec
 Object Mean Diameter      : 13.0 km  (src: astorb)
 Speed of the shadow       : 14.6 km/s
 Elongation to Moon & Sun  : 154° (sunlit = 25%), Sun = 95°
 Cross-track uncertainty   : 0.3 mas = 0 km = 0.04 path-width (1-sig)
 RUWE and duplicate source : 0.87 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#65

 
 [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

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