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2023-07-21 / UCAC4 335-114291 / (171) Ophelia

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Jean Bourgeois O+ VID M200 BE GPS 21:15:00 21:15:42.70 21:15:46.20 21:17:00 1.2 0.6 3.50 30.4
2 show Olivier Schreurs O+ VID M410 BE GPS 21:14:19 21:15:37.7 21:15:48.3 21:17:19 0.5 0.5 10.60 92.2
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

2 observations found in db: sodis

Available (probably) matching predictions (click on the link to switch):
JPL#141 : 8d33af3f-8c19-430d-ab82-1bde8b4fc85a [db: observed]
JPL#141 : 64dc8e56-e629-4516-b6fa-d70ea9ab30a8 [db: observed]
JPL#141 : b35f1568-d22c-46c9-8536-87f82a383117 [db: observed]
JPL#141 : dca2869c-3d15-49d6-b63c-a2c34a3b7a9a [db: observed]

Using prediction 8d33af3f-8c19-430d-ab82-1bde8b4fc85a 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 = 3090.3, 5376.1 km
Circular diameter = 181 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.

Sky projection (artificial light) for occ. time: 2023-07-21, 21:15 UT (JD = 2460147.385)

DAMITQP (h)λ, βJD0JD-JD0φ0VersionModifiedVol-equiv DCmnt
# 1169None6.665 144°, 29° 2.443159e616988.40.0° NoneNone not scaled 2016-01-04
# 1170None6.665 329°, 23° 2.443159e616988.40.0° NoneNone not scaled 2016-01-04
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] : 8d33af3f-8c19-430d-ab82-1bde8b4fc85a [observed]

 Occultation Date + Time   : 2023-07-21 at 21:21:24 UT +/- 0.03 min  [1]
 Object Designation        : (171) Ophelia
 Orbit Class               : MBA
 Star Designation          : GDR3 4116871911616485504
 Star Coordinates (ICRF)   : RA = 17 42 16.2264, DE = -23 04 27.188  [2]
 Star Magnitudes           : G = 14.62 mag, RP = 13.3 mag, BP = 16.6 mag
 Object Magnitude          : V = 13.75 mag
 Estimated Magnitude Drop  : 0.4 mag
 Estimated Max. Duration   : 13.4 sec
 Object Mean Diameter      : 117 km  (src: astorb)
 Speed of the shadow       : 8.7 km/s
 Elongation to Moon & Sun  : 102° (sunlit = 15%), Sun = 147°
 Cross-track uncertainty   : 1.0 mas = 1 km = 0.01 path-width (1-sig)
 RUWE and duplicate source : 0.99 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#141

 Object is a Gaia mass determination target !

 [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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