Cora»Occultation

2026-04-18 / UCAC4 375-137745 / (1409) Isko

#	OBS	Observer	Occ	Meth.	Instr.	CC	TSRC	UT1	UT2	UT3	UT4	UT2E	UT3E	Dur.	Chrd
1	show	Zdenek Sikac	O+	VID	T150	CZ	GPS	02:10:01	02:11:01.32	02:11:03.80	02:12:03	0.020	0.020	2.48	21.8
2	show	Piotr Walczak, Romuald Michalak	O+	VID	M130	PL	GPS	02:10:30	02:11:35.19	02:11:36.90	02:12:38	0.120	0.120	1.71	15.0
3	show	Deborah Smith	O-	VID	M250	ES	GPS	02:06:03	::	::	02:08:03
4	show	Marek Zawilski, Mieczyslaw Borkowski	O-	VID	M200	PL	GPS	02:10:43	::	::	02:13:01

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 : 3c957b00-33e6-11f1-6999-70165ffbd8da [db: asteroids]

Using prediction 3c957b00-33e6-11f1-6999-70165ffbd8da 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 = 2630.2, 29.6 km
Circular diameter = 45 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] : 3c957b00-33e6-11f1-6999-70165ffbd8da [asteroids] Occultation Date + Time : 2026-04-18 at 02:09:09 UT +/- 0.0 min [1] Object Designation : (1409) Isko Orbit Class : MBA Star Designation : GDR3 4103447901048326144 Star Coordinates (ICRF) : RA = 18 39 27.6614, DE = -15 03 59.773 [2] Star Magnitudes : G = 11.64 mag, RP = 11.1 mag, BP = 12.01 mag Object Magnitude : V = 16.07 mag Estimated Magnitude Drop : 4.5 mag Estimated Max. Duration : 4.0 sec Object Mean Diameter : 35.5 km (src: astorb) Speed of the shadow : 8.8 km/s Elongation to Moon & Sun : 116° (sunlit = 1%), Sun = 108° Cross-track uncertainty : 0.3 mas = 0 km = 0.01 path-width (1-sig) RUWE and duplicate source : 0.8 mas, dup.src = 0 (0:false, 1:true) Ephemeris Reference : JPL#76 Note : FP:true [1] time t0 of closest geocentric approach c/a, [2] including proper motion until t0

Event Details

 Occultation UUID [and DB] : 3c957b00-33e6-11f1-6999-70165ffbd8da [asteroids]

 Occultation Date + Time   : 2026-04-18 at 02:09:09 UT +/- 0.0 min  [1]
 Object Designation        : (1409) Isko
 Orbit Class               : MBA
 Star Designation          : GDR3 4103447901048326144
 Star Coordinates (ICRF)   : RA = 18 39 27.6614, DE = -15 03 59.773  [2]
 Star Magnitudes           : G = 11.64 mag, RP = 11.1 mag, BP = 12.01 mag
 Object Magnitude          : V = 16.07 mag
 Estimated Magnitude Drop  : 4.5 mag
 Estimated Max. Duration   : 4.0 sec
 Object Mean Diameter      : 35.5 km  (src: astorb)
 Speed of the shadow       : 8.8 km/s
 Elongation to Moon & Sun  : 116° (sunlit = 1%), Sun = 108°
 Cross-track uncertainty   : 0.3 mas = 0 km = 0.01 path-width (1-sig)
 RUWE and duplicate source : 0.8 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#76
 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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