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2022-08-11 / 4UC 386-130071 / (2241) Alcathous

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Peter Birtwhistle O+ CCD M405 UK NTP 23:04:49 23:04:59.82 23:05:01.35 23:05:19 0.11 0.11 1.53 19.4
2 show Derrick Ward O+ CCD M200 UK NTP 23:03:07 23:05:00.33 23:05:05.4 23:07:07 0.17 0.5 5.07 64.4
3 show Simon Kidd O+ CCD M350 UK GPS++ 23:03:53 23:04:52.09 23:04:58.81 23:06:10 0.03 0.03 6.72 85.3
4 show Luke Broom-Lynne O+ VID M250 UK GPS++ 23:04:44 23:04:46.73 23:04:55.01 23:05:11 0.08 0.08 8.28 105.2
5 show William Stewart O+ VID M279 UK GPS++ 23:03:23 23:05:06.67 23:05:14.67 23:07:01 0.08 0.08 8.00 101.6
6 show Peter Tickner O- CCD M356 UK 23:03:10 23:07:14
7 show Philip Denyer O- VID M235 UK 23:03:30 23:06:17
8 show Jan-Maarten Winkel O- VID M356 NL 23:03:23 23:05:25
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: euraster

Available (probably) matching predictions (click on the link to switch):
JPL#88 : 6b4667c8-57ed-4292-89f8-673b667c7699 [db: observed]

Using prediction 6b4667c8-57ed-4292-89f8-673b667c7699 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 = 130 x 105 km
a',b' = 64.9, 52.7 km
X0,Y0 = 306.7, 5.7 km
Mean diameter = 117 km

From 5 chords (VID,CCD)








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Map with groundtrack and observer stations

Event Details 
 Occultation UUID [and DB] : 6b4667c8-57ed-4292-89f8-673b667c7699 [observed]

 Occultation Date + Time   : 2022-08-11 at 23:06:52 UT +/- 0.06 min  [1]
 Object Designation        : (2241) Alcathous
 Orbit Class               : JTRO
 Star Designation          : GDR3 4185930587612613376
 Star Coordinates (ICRF)   : RA = 19 16 39.9161, DE = -12 58 57.340  [2]
 Star Magnitudes           : G = 12.44 mag, RP = 11.51 mag, BP = 13.36 mag
 Object Magnitude          : V = 15.79 mag
 Estimated Magnitude Drop  : 3.4 mag
 Estimated Max. Duration   : 9.0 sec
 Object Mean Diameter      : 115 km  (src: astorb)
 Speed of the shadow       : 12.7 km/s
 Elongation to Moon & Sun  : 32° (sunlit = 100%), Sun = 148°
 Cross-track uncertainty   : 6.7 mas = 20 km = 0.18 path-width (1-sig)
 RUWE and duplicate source : 0.98 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#88

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

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