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2025-07-16 / UCAC4 316-118748 / (106) Dione

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Deborah Smith O+ VID M150 ES GPS 22:43:15 22:45:08.329 22:45:22.329 22:47:16 3.074 3.074 14.00 151.2
2 show Deborah Smith O+ VID M200 ES GPS 22:43:20 22:45:12.951 22:45:26.350 22:47:20 3.565 3.565 13.40 144.7
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#146 : 427421d0-8536-11ef-78cd-b870ff7b45de [db: asteroids]

Using prediction 427421d0-8536-11ef-78cd-b870ff7b45de 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 = 44.3, 24.7 km
Circular diameter = 157 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] : 427421d0-8536-11ef-78cd-b870ff7b45de [asteroids]

 Occultation Date + Time   : 2025-07-16 at 22:46:21 UT +/- 0.01 min  [1]
 Object Designation        : (106) Dione
 Orbit Class               : MBA
 Star Designation          : GDR3 4061017953485752576
 Star Coordinates (ICRF)   : RA = 17 44 43.9814, DE = -26 49 18.334  [2]
 Star Magnitudes           : G = 14.62 mag, RP = 13.53 mag, BP = 15.84 mag
 Object Magnitude          : V = 12.93 mag
 Estimated Magnitude Drop  : 0.2 mag
 Estimated Max. Duration   : 13.5 sec
 Object Mean Diameter      : 146.6 km  (src: astorb)
 Speed of the shadow       : 10.8 km/s
 Elongation to Moon & Sun  : 104° (sunlit = 62%), Sun = 152°
 Cross-track uncertainty   : 1.0 mas = 1 km = 0.01 path-width (1-sig)
 RUWE and duplicate source : 0.89 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#146

 Object is a Gaia mass determination target !

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

More Data and Informations
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