Cora»Occultation

2024-12-16 / UCAC4 466-020402 / (909) Ulla

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Tim Haymes	O+	VID	M280	GB	GPS	23:08:30	23:09:52.50	23:09:59.08	23:11:30	0.20	0.10	6.58	89.5
2	show	Simon Kidd	O+	VID	M350	GB	GPS	23:09:00	23:09:46.920	23:09:53.880	23:11:00	0.04	0.04	6.96	94.7
3	show	Malcolm Jennings	O-	VID	M276	GB	GPS	23:08:00			23:12:00

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#143 : c4bf8430-ddb5-11f0-547e-f06cfd2d1432 [db: observed]

Using prediction c4bf8430-ddb5-11f0-547e-f06cfd2d1432 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 = -733.8, 13.1 km
Circular diameter = 97 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] : c4bf8430-ddb5-11f0-547e-f06cfd2d1432 [observed] Occultation Date + Time : 2024-12-16 at 23:06:43 UT +/- 0.01 min [1] Object Designation : (909) Ulla Orbit Class : MBA Star Designation : GDR3 3127110025443091968 Star Coordinates (ICRF) : RA = 06 41 08.2333, DE = +03 03 52.061 [2] Star Magnitudes : G = 13.64 mag, RP = 13.16 mag, BP = 13.95 mag Object Magnitude : V = 13.99 mag Estimated Magnitude Drop : 0.9 mag Estimated Max. Duration : 8.6 sec Object Mean Diameter : 116.4 km (src: astorb) Speed of the shadow : 13.6 km/s Elongation to Moon & Sun : 25° (sunlit = 97%), Sun = 155° Cross-track uncertainty : 1.0 mas = 1 km = 0.02 path-width (1-sig) RUWE and duplicate source : 1.09 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#143 Note : FP:true [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

Occultation UUID [and DB] : c4bf8430-ddb5-11f0-547e-f06cfd2d1432 [observed] Occultation Date + Time : 2024-12-16 at 23:06:43 UT +/- 0.01 min [1] Object Designation : (909) Ulla Orbit Class : MBA Star Designation : GDR3 3127110025443091968 Star Coordinates (ICRF) : RA = 06 41 08.2333, DE = +03 03 52.061 [2] Star Magnitudes : G = 13.64 mag, RP = 13.16 mag, BP = 13.95 mag Object Magnitude : V = 13.99 mag Estimated Magnitude Drop : 0.9 mag Estimated Max. Duration : 8.6 sec Object Mean Diameter : 116.4 km (src: astorb) Speed of the shadow : 13.6 km/s Elongation to Moon & Sun : 25° (sunlit = 97%), Sun = 155° Cross-track uncertainty : 1.0 mas = 1 km = 0.02 path-width (1-sig) RUWE and duplicate source : 1.09 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#143 Note : FP:true [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

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