Cora»Occultation

2025-08-31 / UCAC4 306-249731 / (297) Caecilia

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Jiri Kubanek	O+	VID	M200	CZ	GPS	19:18:10	19:19:04.12	19:19:11.47	19:20:10	0.180	0.180	7.35	37.5
2	show	Michal Rottenborn	O+	VID	M254	CZ	GPS	19:18:09	19:19:04.270	19:19:11.770	19:20:09	0.100	0.100	7.50	38.2
3	show	Jiri Polak	O+	VID	M300	CZ	NTP	19:17:09	19:19:03.91	19:19:11.21	19:21:09	0.050	0.050	7.30	37.2
4	show	Sven Andersson	O-	VID	M360	DE	GPS	19:18:49	::	::	19:19:49

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

4 observations found in db: sodis

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

JPL#76 : 5b7b5b50-ddb7-11f0-547e-8c07efbfe683 [db: observed]

Using prediction 5b7b5b50-ddb7-11f0-547e-8c07efbfe683 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:
Size = 40 x 37 km
a',b' = 20.1, 18.6 km
X0,Y0 = 2737.1, 18.0 km
Mean diameter = 39 km

From 3 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).

Check SiMDA for size and mass data.

Check Johnston Archive for satellites.

Sky projection (artificial light) for occ. time: 2025-08-31, 19:18 UT (JD = 2460919.304)

DAMIT	Q	P (h)	λ, β	JD0	JD-JD0	φ0	Version	Modified	Vol-equiv D	Cmnt
# 470	None	4.151	223°, -53°	2.451051e6	9868.3	0.0°	None	None	not scaled	2013-02-11
# 471	None	4.151	47°, -33°	2.451051e6	9868.3	0.0°	None	None	not scaled	2013-02-11

Q: model quality flag (0-5, 5=highest) | P: rotation period | λ,β: ecl. lon. and lat. of spin axis (J2000) | JD: initial time (epoch) | φ0: initial rotation angle for JD0

Image size: 300px. Transparent image background for copy & paste

Map with groundtrack and observer stations

Event Details
Occultation UUID [and DB] : 5b7b5b50-ddb7-11f0-547e-8c07efbfe683 [observed] Occultation Date + Time : 2025-08-31 at 19:02:05 UT +/- 0.04 min [1] Object Designation : (297) Caecilia Orbit Class : MBA Star Designation : GDR3 4048330688813052032 Star Coordinates (ICRF) : RA = 18 36 56.5921, DE = -28 52 51.033 [2] Star Magnitudes : G = 12.67 mag, RP = 12.16 mag, BP = 13.01 mag Object Magnitude : V = 14.01 mag Estimated Magnitude Drop : 1.6 mag Estimated Max. Duration : 7.7 sec Object Mean Diameter : 39.5 km (src: astorb) Speed of the shadow : 5.1 km/s Elongation to Moon & Sun : 24° (sunlit = 55%), Sun = 119° Cross-track uncertainty : 0.7 mas = 1 km = 0.03 path-width (1-sig) RUWE and duplicate source : 0.83 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#76 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] : 5b7b5b50-ddb7-11f0-547e-8c07efbfe683 [observed]

 Occultation Date + Time   : 2025-08-31 at 19:02:05 UT +/- 0.04 min  [1]
 Object Designation        : (297) Caecilia
 Orbit Class               : MBA
 Star Designation          : GDR3 4048330688813052032
 Star Coordinates (ICRF)   : RA = 18 36 56.5921, DE = -28 52 51.033  [2]
 Star Magnitudes           : G = 12.67 mag, RP = 12.16 mag, BP = 13.01 mag
 Object Magnitude          : V = 14.01 mag
 Estimated Magnitude Drop  : 1.6 mag
 Estimated Max. Duration   : 7.7 sec
 Object Mean Diameter      : 39.5 km  (src: astorb)
 Speed of the shadow       : 5.1 km/s
 Elongation to Moon & Sun  : 24° (sunlit = 55%), Sun = 119°
 Cross-track uncertainty   : 0.7 mas = 1 km = 0.03 path-width (1-sig)
 RUWE and duplicate source : 0.83 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#76
 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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