Occultation event with (5144) Achates, event index number 4513
Regions able to see the event: NMexico
Geocentric closest approach at 2026/10/29 08:53:37 UTC
J2000 position of star is 05:25:04.4 +32:32:37
Equinox of date position of star is 05:26:49.5 +32:33:57
Star is 6 degrees from the moon. Moon is 86% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=15.1
Use an exposure time of 1.85 seconds with the standard RECON-QHY system.
SNR of 3.9 per integration for unocculted signal
Expected flux drop is 21% with SNR of 0.8 for the occulted depth (per occulted point)
Apparent velocity is 10.7 km/sec on the sky relative to the star, or, 9.9 arcsec/hr.
Position angle of asteroid motion is 100.5 degrees
The recommended exposure time corresponds to 19.9 km per image.
The 1-sigma error in the time of the event is 0.6 seconds.
The 1-sigma cross-track error in the shadow position is 27.9 km.
The sky-plane scale is 3888.3 km/arcsec.
Diameter estimates:
87.5 km assuming a 5% albedo, maximum of 8.1 sec for a central chord
35.7 km assuming a 30% albedo, maximum of 3.3 sec for a central chord
Cross-track diameter of 81.0 km used for deployment plan.
Star training set for 5144_Achates, (2026/10/29 08:54UT) Object RA Dec mag sep mel Aldebaran 04:37:27.8 +16:33:40 0.8 19.51 14 Alnath 05:27:59.4 +28:37:39 1.6 3.95 3 25Chi Aur 05:34:28.6 +32:12:33 4.8 1.65 6 PPM 070293 05:25:45.8 +32:38:54 8.3 0.24 6 PPM 070312 05:26:31.9 +32:43:48 10.0 0.18 6 PPM 070327 05:27:13.3 +32:25:55 10.1 0.16 5 5144_Achates 05:26:49.5 +32:33:57 15.1 6 Positions are for equinox of date
Star training set for 5144_Achates, (2026/10/29 08:54UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 19.51 14 Alnath 05:26:17.6 +28:36:22 1.6 3.95 3 25Chi Aur 05:32:43.7 +32:11:31 4.8 1.65 6 PPM 070293 05:24:00.7 +32:37:32 8.3 0.24 6 PPM 070312 05:24:46.7 +32:42:27 10.0 0.18 6 PPM 070327 05:25:28.3 +32:24:36 10.1 0.16 5 5144_Achates 05:25:04.4 +32:32:37 15.1 6 Positions are for J2000