Collaborative Occultation Resources and Archive (CORA)

2025-03-20 / UCAC4 512-038382 / (7875) 1991 ES1

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Michal Rottenborn	O+	VID	M254	CZ	GPS	22:03:46	22:05:44.59	22:05:45.84	22:07:46	0.05	0.05	1.25	14.1
2	show	Jiri Kubanek	O+	VID	M200	CZ	GPS	22:04:21	22:05:49.52	22:05:50.57	22:07:21	0.10	0.07	1.05	11.9

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#62 : b42c3180-8aba-11ef-78cd-9dfffe3fbfb1 [db: asteroids]

Using prediction b42c3180-8aba-11ef-78cd-9dfffe3fbfb1 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 = 925.5, 19.9 km
Circular diameter = 14 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).

Check SiMDA for size and mass data.

Check Johnston Archive for satellites.

Map with groundtrack and observer stations

Event Details
Occultation UUID [and DB] : b42c3180-8aba-11ef-78cd-9dfffe3fbfb1 [asteroids] Occultation Date + Time : 2025-03-20 at 21:58:20 UT +/- 0.0 min [1] Object Designation : (7875) 1991 ES1 Orbit Class : MBA Star Designation : GDR3 3163089898490575616 Star Coordinates (ICRF) : RA = 07 24 44.8431, DE = +12 20 16.209 [2] Star Magnitudes : G = 12.89 mag, RP = 12.32 mag, BP = 13.3 mag Object Magnitude : V = 16.72 mag Estimated Magnitude Drop : 3.9 mag Estimated Max. Duration : 1.0 sec Object Mean Diameter : 11.1 km (src: astorb) Speed of the shadow : 11.3 km/s Elongation to Moon & Sun : 139° (sunlit = 65%), Sun = 110° Cross-track uncertainty : 0.2 mas = 0 km = 0.02 path-width (1-sig) RUWE and duplicate source : 1.09 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#62 [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

 Occultation UUID [and DB] : b42c3180-8aba-11ef-78cd-9dfffe3fbfb1 [asteroids]

 Occultation Date + Time   : 2025-03-20 at 21:58:20 UT +/- 0.0 min  [1]
 Object Designation        : (7875) 1991 ES1
 Orbit Class               : MBA
 Star Designation          : GDR3 3163089898490575616
 Star Coordinates (ICRF)   : RA = 07 24 44.8431, DE = +12 20 16.209  [2]
 Star Magnitudes           : G = 12.89 mag, RP = 12.32 mag, BP = 13.3 mag
 Object Magnitude          : V = 16.72 mag
 Estimated Magnitude Drop  : 3.9 mag
 Estimated Max. Duration   : 1.0 sec
 Object Mean Diameter      : 11.1 km  (src: astorb)
 Speed of the shadow       : 11.3 km/s
 Elongation to Moon & Sun  : 139° (sunlit = 65%), Sun = 110°
 Cross-track uncertainty   : 0.2 mas = 0 km = 0.02 path-width (1-sig)
 RUWE and duplicate source : 1.09 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#62

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

More Data and Informations

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