Cora»Occultation

2026-02-20 / UCAC4 629-041023 / (54598) Bienor

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Carles Schnabel	O+	VID	M400	ES	GPS	21:56:53	21:58:45.1	21:58:47.90	22:00:50	0.300	0.130	2.80	47.3
2	show	Jorge JUAN, Carles Schnabel	O+	VID	M410	ES	GPS	21:55:46	21:58:45.4	21:58:48.9	22:02:08	0.300	0.300	3.50	59.1
3	show	Joan Rovira	O+	VID	M250	ES	GPS	21:56:15	21:58:43.40	21:58:49.80	21:59:35	0.300	0.300	6.40	108.2
4	show	Deborah Smith	O-	VID	M300	ES	GPS	21:58:22	::	::	22:00:22
5	show	Deborah Smith	O-	VID	M250	ES	GPS	21:58:15	::	::	22:00:15
6	show	Michael OConnell	O-	VID	M350	ES	NTP	21:58:26	::	::	22:00:26
7	show	Javier Prat, Pedro Martorell	O-	CCD	M310	ES	GPS	21:57:03	::	::	22:01:03
8	show	Faustino Garcia	O-	CCD	T250	ES	GPS	21:56:07	::	::	22:02:07

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

8 observations found in db: sodis

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

JPL#75 : dbd64370-f8eb-11ef-4809-b2a7ddd678e7 [db: cetnos]

JPL#76 : 11ac89b0-408a-11f0-4ed7-c902efbf882c [db: cetnos]

Using prediction dbd64370-f8eb-11ef-4809-b2a7ddd678e7 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 = 140 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] : dbd64370-f8eb-11ef-4809-b2a7ddd678e7 [cetnos] Occultation Date + Time : 2026-02-20 at 21:59:18 UT +/- 0.07 min [1] Object Designation : (54598) Bienor Orbit Class : CEN Star Designation : GDR3 0906682787486423936 Star Coordinates (ICRF) : RA = 07 57 16.4824, DE = +35 46 55.827 [2] Star Magnitudes : G = 15.2 mag, RP = 14.65 mag, BP = 15.59 mag Object Magnitude : V = 18.84 mag Estimated Magnitude Drop : 3.7 mag Estimated Max. Duration : 6.6 sec Object Mean Diameter : 111.0 km (src: CORA+astorb) Speed of the shadow : 16.9 km/s Elongation to Moon & Sun : 98° (sunlit = 13%), Sun = 140° Cross-track uncertainty : 4.3 mas = 38 km = 0.35 path-width (1-sig) RUWE and duplicate source : 0.93 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#75 Object is a "TNOs are cool" target ! [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

 Occultation UUID [and DB] : dbd64370-f8eb-11ef-4809-b2a7ddd678e7 [cetnos]

 Occultation Date + Time   : 2026-02-20 at 21:59:18 UT +/- 0.07 min  [1]
 Object Designation        : (54598) Bienor
 Orbit Class               : CEN
 Star Designation          : GDR3 0906682787486423936
 Star Coordinates (ICRF)   : RA = 07 57 16.4824, DE = +35 46 55.827  [2]
 Star Magnitudes           : G = 15.2 mag, RP = 14.65 mag, BP = 15.59 mag
 Object Magnitude          : V = 18.84 mag
 Estimated Magnitude Drop  : 3.7 mag
 Estimated Max. Duration   : 6.6 sec
 Object Mean Diameter      : 111.0 km  (src: CORA+astorb)
 Speed of the shadow       : 16.9 km/s
 Elongation to Moon & Sun  : 98° (sunlit = 13%), Sun = 140°
 Cross-track uncertainty   : 4.3 mas = 38 km = 0.35 path-width (1-sig)
 RUWE and duplicate source : 0.93 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#75

 Object is a "TNOs are cool" target !

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

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