Collaborative Occultation Resources and Archive (CORA)

Occultations | Observations | Reports | Info + Credits | JOA | Admin | Login

2017-11-19 / 2UC 32706255 / (18) Melpomene

#OBSObserverOccMeth.Instr.CC TSRCUT1UT2UT3UT4UT2EUT3EDur.Chrd
1 show Tim Haymes O+ VID M300 UK GPS++ 05:34:00 05:36:30.73 05:36:33.37 05:49:00 0.02 0.02 2.64 76.8
2 show Philip Denyer O+ VID M235 UK GPS++ 05:33:00 05:36:32.04 05:36:36.40 05:38:59 0.09 0.09 4.36 126.9
3 show John Talbot O+ VID M303 UK GPS++ 05:34:34 05:36:29.95 05:36:32.97 05:38:32 0.14 0.04 3.02 87.9
4 show Simon Kidd O+ CCD M350 UK NTP 05:31:59 05:36:31.50 05:36:36.70 05:38:12 0.1 0.1 5.20 151.3
UT1/UT4: Begin/End of observation | UT2/UT3: Begin/End of occultation | Dur: Reported duration in seconds | Chrd: Corresponding chord length in km | More

4 observations found in db: euraster

Available (probably) matching predictions (click on the link to switch):
JPL#129 : b8962c6c-efdd-416e-9d77-a3c6f7a81b15 [db: observed]

Using prediction b8962c6c-efdd-416e-9d77-a3c6f7a81b15 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 = 150 x 111 km
a',b' = 75.0, 55.7 km
X0,Y0 = -1155.2, 21.8 km
Mean diameter = 129 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: 2017-11-19, 05:35 UT (JD = 2458076.733)

DAMITQP (h)λ, βJD0JD-JD0φ0VersionModifiedVol-equiv DCmnt
# 993None11.570 11°, 14° 2.436249e621827.70.0° NoneNone not scaled 2016-01-04
# 18084.011.570 12°, 21° 2.436249e621827.70.0° None2017-06-19 146.0 +/- 3.0 km 2017-06-06
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] : b8962c6c-efdd-416e-9d77-a3c6f7a81b15 [observed]

 Occultation Date + Time   : 2017-11-19 at 05:38:34 UT +/- 0.01 min  [1]
 Object Designation        : (18) Melpomene
 Orbit Class               : MBA
 Star Designation          : GDR3 3799613603763299712
 Star Coordinates (ICRF)   : RA = 11 45 11.8027, DE = +02 35 21.903  [2]
 Star Magnitudes           : G = 11.76 mag, RP = 11.15 mag, BP = 12.2 mag
 Object Magnitude          : V = 11.62 mag
 Estimated Magnitude Drop  : 0.7 mag
 Estimated Max. Duration   : 4.8 sec
 Object Mean Diameter      : 141 km  (src: astorb)
 Speed of the shadow       : 29.1 km/s
 Elongation to Moon & Sun  : 70° (sunlit = 1%), Sun = 62°
 Cross-track uncertainty   : 3.0 mas = 6 km = 0.05 path-width (1-sig)
 RUWE and duplicate source : 0.89 mas, dup.src = 0  (0:false, 1:true)

 Ephemeris Reference       : JPL#129

 
 [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
(If error 404: link not valid which means no data available)

Aladin Sky Atlas
Aladin Lite direct link (has Gaia overlay)