Cora»Occultation

2025-10-31 / UCAC4 319-186811 / (106) Dione

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Deborah Smith, Eric Smith	O+	VID	M150	ES	GPS	19:17:30	19:19:30.686	19:19:33.226	19:21:30	0.148	0.148	2.54	79.2
2	show	Deborah Smith	O+	VID	M300	ES	GPS	19:17:29	19:19:30.735	19:19:33.260	19:21:29	0.069	0.069	2.52	78.6
3	show	Deborah Smith	O+	VID	M200	ES	GPS	19:17:30	19:19:28.122	19:19:32.817	19:21:30	0.118	0.118	4.69	146.3

UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

3 observations found in db: sodis

Available (probably) matching predictions (click on the link to switch):

JPL#156 : a724e7a0-ddb8-11f0-547e-a4e4fded27a9 [db: observed]

Using prediction a724e7a0-ddb8-11f0-547e-a4e4fded27a9 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:
Ellipse profile fit was not successful. Trying circular fit.

Circular diameter = 155 km

From 3 chords (VID)

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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] : a724e7a0-ddb8-11f0-547e-a4e4fded27a9 [observed] Occultation Date + Time : 2025-10-31 at 19:17:16 UT +/- 0.0 min [1] Object Designation : (106) Dione Orbit Class : MBA Star Designation : GDR3 4052042365194710912 Star Coordinates (ICRF) : RA = 18 29 17.5930, DE = -26 22 44.122 [2] Star Magnitudes : G = 13.11 mag, RP = 11.99 mag, BP = 14.43 mag Object Magnitude : V = 13.92 mag Estimated Magnitude Drop : 1.2 mag Estimated Max. Duration : 4.7 sec Object Mean Diameter : 146.6 km (src: astorb) Speed of the shadow : 31.2 km/s Elongation to Moon & Sun : 58° (sunlit = 72%), Sun = 58° Cross-track uncertainty : 0.7 mas = 1 km = 0.01 path-width (1-sig) RUWE and duplicate source : 0.95 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#156 Note : FP:true Object is a Gaia mass determination target ! [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

 Occultation UUID [and DB] : a724e7a0-ddb8-11f0-547e-a4e4fded27a9 [observed]

 Occultation Date + Time   : 2025-10-31 at 19:17:16 UT +/- 0.0 min  [1]
 Object Designation        : (106) Dione
 Orbit Class               : MBA
 Star Designation          : GDR3 4052042365194710912
 Star Coordinates (ICRF)   : RA = 18 29 17.5930, DE = -26 22 44.122  [2]
 Star Magnitudes           : G = 13.11 mag, RP = 11.99 mag, BP = 14.43 mag
 Object Magnitude          : V = 13.92 mag
 Estimated Magnitude Drop  : 1.2 mag
 Estimated Max. Duration   : 4.7 sec
 Object Mean Diameter      : 146.6 km  (src: astorb)
 Speed of the shadow       : 31.2 km/s
 Elongation to Moon & Sun  : 58° (sunlit = 72%), Sun = 58°
 Cross-track uncertainty   : 0.7 mas = 1 km = 0.01 path-width (1-sig)
 RUWE and duplicate source : 0.95 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#156
 Note                      : FP:true

 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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