Cora»Occultation

2025-12-06 / UCAC4 414-142029 / (1311) Knopfia

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Andrea Manna	O+	VID	M200	CH	GPS	17:30:03	17:33:23.93	17:33:24.57	17:35:58	0.080	0.080	0.64	14.1
2	show	Stefano Sposetti	O+	VID	M420	CH	GPS	17:32:30	17:33:24.382	17:33:24.888	17:34:30	0.015	0.015	0.51	11.3

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

2 observations found in db: sodis

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

JPL#73 : d37a8b70-ddb8-11f0-547e-52aafdef572e [db: observed]

Using prediction d37a8b70-ddb8-11f0-547e-52aafdef572e 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 = 1392.2, 18.1 km
Circular diameter = 23 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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Check Johnston Archive for satellites.

Sky projection (artificial light) for occ. time: 2025-12-06, 17:33 UT (JD = 2461016.231)

DAMIT	Q	P (h)	λ, β	JD0	JD-JD0	φ0	Version	Modified	Vol-equiv D	Cmnt
# 2926	1.5	32.328	74°, -35°	2.450938e6	10078.2	0.0°	None	2018-07-19	not scaled	2018-07-18
# 2927	1.5	32.328	260°, -34°	2.450938e6	10078.2	0.0°	None	2018-07-19	not scaled	2018-07-18

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] : d37a8b70-ddb8-11f0-547e-52aafdef572e [observed] Occultation Date + Time : 2025-12-06 at 17:31:34 UT +/- 0.0 min [1] Object Designation : (1311) Knopfia Orbit Class : MBA Star Designation : GDR3 2622551286281938176 Star Coordinates (ICRF) : RA = 22 23 29.8986, DE = -07 12 34.267 [2] Star Magnitudes : G = 12.69 mag, RP = 12.13 mag, BP = 13.09 mag Object Magnitude : V = 17.45 mag Estimated Magnitude Drop : 4.8 mag Estimated Max. Duration : 0.6 sec Object Mean Diameter : 14.1 km (src: astorb) Speed of the shadow : 22.1 km/s Elongation to Moon & Sun : 124° (sunlit = 95%), Sun = 80° Cross-track uncertainty : 0.3 mas = 0 km = 0.04 path-width (1-sig) RUWE and duplicate source : 1.03 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#73 Note : FP:true [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

 Occultation UUID [and DB] : d37a8b70-ddb8-11f0-547e-52aafdef572e [observed]

 Occultation Date + Time   : 2025-12-06 at 17:31:34 UT +/- 0.0 min  [1]
 Object Designation        : (1311) Knopfia
 Orbit Class               : MBA
 Star Designation          : GDR3 2622551286281938176
 Star Coordinates (ICRF)   : RA = 22 23 29.8986, DE = -07 12 34.267  [2]
 Star Magnitudes           : G = 12.69 mag, RP = 12.13 mag, BP = 13.09 mag
 Object Magnitude          : V = 17.45 mag
 Estimated Magnitude Drop  : 4.8 mag
 Estimated Max. Duration   : 0.6 sec
 Object Mean Diameter      : 14.1 km  (src: astorb)
 Speed of the shadow       : 22.1 km/s
 Elongation to Moon & Sun  : 124° (sunlit = 95%), Sun = 80°
 Cross-track uncertainty   : 0.3 mas = 0 km = 0.04 path-width (1-sig)
 RUWE and duplicate source : 1.03 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#73
 Note                      : FP:true

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

More Data and Informations

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