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2020-11-04 / 4UC 557-034202 / (971) Alsatia

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Peter Tickner O+ CCD M356 UK GPS 00:34:27 00:37:13.90 00:37:25.11 00:40:27 0.55 0.25 11.21 69.5
2 show Simon Kidd O+ CCD M350 UK GPS++ 00:36:30 00:37:24.43 00:37:31.70 00:38:45 0.19 0.22 7.27 45.1
3 show Pierre Le Cam O- CCD M250 FR 00:34:10 00:38:10
4 show John Talbot O- VID M303 UK 00:36:31 00:38:28
5 show Tim Haymes O- CCD M279 UK 00:34:00 00:41:00
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

5 observations found in db: euraster

Available (probably) matching predictions (click on the link to switch):
JPL#63 : b5576832-6a9a-407d-846e-6bbd12f4fdfd [db: observed]

Using prediction b5576832-6a9a-407d-846e-6bbd12f4fdfd 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 = 3280.7, 50.9 km
Circular diameter = 72 km

From 2 chords (CCD)








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] : b5576832-6a9a-407d-846e-6bbd12f4fdfd [observed]

 Occultation Date + Time   : 2020-11-04 at 00:36:29 UT +/- 0.03 min  [1]
 Object Designation        : (971) Alsatia
 Orbit Class               : MBA
 Star Designation          : GDR3 3378344072999467776
 Star Coordinates (ICRF)   : RA = 06 50 18.6917, DE = +21 19 23.017  [2]
 Star Magnitudes           : G = 14.19 mag, RP = 13.44 mag, BP = 14.78 mag
 Object Magnitude          : V = 13.87 mag
 Estimated Magnitude Drop  : 0.6 mag
 Estimated Max. Duration   : 10.4 sec
 Object Mean Diameter      : 64 km  (src: astorb)
 Speed of the shadow       : 6.2 km/s
 Elongation to Moon & Sun  : 22° (sunlit = 90%), Sun = 120°
 Cross-track uncertainty   : 1.7 mas = 1 km = 0.03 path-width (1-sig)
 RUWE and duplicate source : 4.75 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#63

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

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