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2026-05-26 / UCAC4 386-064479 / (116) Sirona

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Piotr Walczak O+ VID M150 PL GPS 20:42:13 20:43:20.1 20:43:28.1 20:44:57 0.500 0.500 8.00 60.0
2 show Marek Zawilski O+ VID M200 PL GPS 20:42:24 20:43:22.99 20:43:31.54 20:44:20 0.070 0.070 8.55 64.1
3 show Anna Marciniak O+ CCD M400 PL GPS 20:41:40 20:43:40.16 20:43:48.58 20:45:53 0.050 0.060 8.42 63.1
4 show Anna Marciniak O+ CCD M350 PL NTP 20:41:50 20:43:49.03 20:43:57.76 20:45:52 0.100 0.100 8.73 65.5
5 show Nikolai Wuensche O+ VID M300 DE GPS 20:42:00 20:44:09.23 20:44:16.33 20:46:30 0.050 0.050 7.10 53.2
6 show Konrad Guhl O+ CCD M306 DE GPS 20:43:30 20:44:12.90 20:44:21.59 20:45:15 0.130 0.190 8.69 65.2
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

6 observations found in db: sodis

Available (probably) matching predictions (click on the link to switch):
JPL#142 : a4845440-33bc-11f1-6999-dfc3bff8b651 [db: asteroids]

Using prediction a4845440-33bc-11f1-6999-dfc3bff8b651 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 = 70 x 41 km
a',b' = 35.1, 20.6 km
X0,Y0 = -813.0, -1.2 km
Mean diameter = 54 km

From 6 chords (CCD,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: 2026-05-26, 20:42 UT (JD = 2461187.363)

DAMITQP (h)λ, βJD0JD-JD0φ0VersionModifiedVol-equiv DCmnt
# 1262None12.032 51°, -53° 2.450392e610795.40.0° NoneNone not scaled 2016-01-12
# 1263None12.033 222°, -53° 2.450392e610795.40.0° NoneNone not scaled 2016-01-12
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] : a4845440-33bc-11f1-6999-dfc3bff8b651 [asteroids]

 Occultation Date + Time   : 2026-05-26 at 20:41:17 UT +/- 0.01 min  [1]
 Object Designation        : (116) Sirona
 Orbit Class               : MBA
 Star Designation          : GDR3 6300415898780847872
 Star Coordinates (ICRF)   : RA = 14 26 03.7063, DE = -12 55 35.655  [2]
 Star Magnitudes           : G = 11.88 mag, RP = 11.2 mag, BP = 12.41 mag
 Object Magnitude          : V = 11.59 mag
 Estimated Magnitude Drop  : 0.6 mag
 Estimated Max. Duration   : 9.6 sec
 Object Mean Diameter      : 71.7 km  (src: astorb)
 Speed of the shadow       : 7.5 km/s
 Elongation to Moon & Sun  : 23° (sunlit = 82%), Sun = 153°
 Cross-track uncertainty   : 2.3 mas = 2 km = 0.04 path-width (1-sig)
 RUWE and duplicate source : 1.08 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#142
 Note                      : FP:true

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

More Data and Informations
SiMDA | 3D Asteroid Catalogue | Johnston Archive | Star at CDS (Vizier) | JPL Small-Body Node | Minor Planet Center | Wikipedia
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