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2021-01-29 / HIP 7732 / (424) Gratia

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Matthieu Conjat O+ CCD M400 FR NTP 21:03:38 21:03:58.25 21:04:00.44 21:04:46 0.25 0.25 2.19 57.2
2 show Paolo Tanga O+ CCD M355 FR GPS++ 21:03:00 21:03:58.04 21:04:00.15 21:05:00 0.01 0.01 2.11 55.1
3 show Pietro Baruffetti O+ VID M300 IT GPS++ 21:02:38 21:04:00.92 21:04:03.24 21:05:39 0.08 0.08 2.32 60.6
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

3 observations found in db: euraster

Available (probably) matching predictions (click on the link to switch):
JPL#85 : 0fb78b9c-b8bc-478e-b0e9-59bb24af2f03 [db: observed]

Using prediction 0fb78b9c-b8bc-478e-b0e9-59bb24af2f03 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 = 65 x 14 km
a',b' = 32.5, 6.8 km
X0,Y0 = 791.7, 30.4 km
Mean diameter = 30 km

From 3 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: 2021-01-29, 21:03 UT (JD = 2459244.377)

DAMITQP (h)λ, βJD0JD-JD0φ0VersionModifiedVol-equiv DCmnt
# 53531.020.060 351°, -24° 2.457227e62017.40.0° None2020-10-05 not scaled 2019-10-23
# 53541.020.060 172°, -6° 2.457227e62017.40.0° 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] : 0fb78b9c-b8bc-478e-b0e9-59bb24af2f03 [observed]

 Occultation Date + Time   : 2021-01-29 at 21:00:14 UT +/- 0.01 min  [1]
 Object Designation        : (424) Gratia
 Orbit Class               : MBA
 Star Designation          : GDR3 2560633083531976064
 Star Coordinates (ICRF)   : RA = 01 39 34.0014, DE = +03 33 02.366  [2]
 Star Magnitudes           : G = 8.57 mag, RP = 8.14 mag, BP = 8.84 mag
 Object Magnitude          : V = 14.86 mag
 Estimated Magnitude Drop  : 6.3 mag
 Estimated Max. Duration   : 3.3 sec
 Object Mean Diameter      : 87 km  (src: astorb)
 Speed of the shadow       : 26.1 km/s
 Elongation to Moon & Sun  : 120° (sunlit = 99%), Sun = 74°
 Cross-track uncertainty   : 2.0 mas = 3 km = 0.04 path-width (1-sig)
 RUWE and duplicate source : 1.68 mas, dup.src = 1  (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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