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2022-03-05 / 4UC 571-046898 / (424) Gratia

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Martin Gutekunst O+ CCD L280 DE NTP 23:23:00 23:24:03.43 23:24:09.61 23:25:59 0.38 0.56 6.18 54.4
2 show Gregor Krannich O+ CCD M350 DE GPS++ 23:22:51 23:24:08.20 23:24:14.62 23:25:21 0.11 0.11 6.42 56.5
3 show R. Boninsegna et al O+ VID M400 BE GPS++ 23:23:31 23:25:03.63 23:25:09.51 23:26:30 0.08 0.28 5.88 51.7
4 show Jean Bourgeois O+ VID M200 BE GPS++ 23:24:45 23:25:00.77 23:25:07.01 23:25:45 0.16 0.08 6.24 54.9
5 show Karl-Ludwig Bath O- CCD M180 DE 23:22:02 23:27:02
6 show Olivier Schreurs O- VID M254 BE 23:23:52 23:26:02
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: euraster

Available (probably) matching predictions (click on the link to switch):
JPL#85 : 502d0799-13cc-4fff-b845-ee3be5318053 [db: observed]

Using prediction 502d0799-13cc-4fff-b845-ee3be5318053 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 = 112 x 54 km
a',b' = 56.2, 26.9 km
X0,Y0 = -1052.1, 30.6 km
Mean diameter = 78 km

From 4 chords (VID,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).

Check SiMDA for size and mass data.

Check Johnston Archive for satellites.

Sky projection (artificial light) for occ. time: 2022-03-05, 23:23 UT (JD = 2459644.474)

DAMITQP (h)λ, βJD0JD-JD0φ0VersionModifiedVol-equiv DCmnt
# 53531.020.060 351°, -24° 2.457227e62417.50.0° None2020-10-05 not scaled 2019-10-23
# 53541.020.060 172°, -6° 2.457227e62417.50.0° None2020-10-05 not scaled 2019-10-23
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] : 502d0799-13cc-4fff-b845-ee3be5318053 [observed]

 Occultation Date + Time   : 2022-03-05 at 23:25:05 UT +/- 0.02 min  [1]
 Object Designation        : (424) Gratia
 Orbit Class               : MBA
 Star Designation          : GDR3 0644686277735901312
 Star Coordinates (ICRF)   : RA = 09 39 47.1478, DE = +24 07 33.371  [2]
 Star Magnitudes           : G = 14.37 mag, RP = 13.91 mag, BP = 14.66 mag
 Object Magnitude          : V = 13.73 mag
 Estimated Magnitude Drop  : 0.5 mag
 Estimated Max. Duration   : 9.9 sec
 Object Mean Diameter      : 87 km  (src: astorb)
 Speed of the shadow       : 8.8 km/s
 Elongation to Moon & Sun  : 114° (sunlit = 12%), Sun = 152°
 Cross-track uncertainty   : 2.0 mas = 2 km = 0.03 path-width (1-sig)
 RUWE and duplicate source : 1.06 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#85

 
 [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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