Occultation event with (9857) Hecamede, event index number 3336
Regions able to see the event: SAmericaN,SAmericaS
Geocentric closest approach at 2026/03/03 08:14:43 UTC
J2000 position of star is 11:53:24.0 -24:14:28
Equinox of date position of star is 11:54:44.0 -24:23:12
Star is 35 degrees from the moon. Moon is 100% illuminated.
Stellar brightness G=14.1, apparent brightess of occulting body is G=15.4
Use an exposure time of 0.30 seconds with the standard RECON-QHY system.
SNR of 9.2 per integration for unocculted signal
Expected flux drop is 77% with SNR of 7.1 for the occulted depth (per occulted point)
Apparent velocity is 15.1 km/sec on the sky relative to the star, or, 17.1 arcsec/hr.
Position angle of asteroid motion is 91.8 degrees
The recommended exposure time corresponds to 4.5 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 29.1 km.
The sky-plane scale is 3162.9 km/arcsec.
Diameter estimates:
51.5 km assuming a 5% albedo, maximum of 3.4 sec for a central chord
21.0 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 49.5 km used for deployment plan.
Star training set for 9857_Hecamede, (2026/03/03 08:15UT) Object RA Dec mag sep mel Spica 13:26:34.5 -11:17:49 1.0 25.41 43 4Gam Crv 12:17:09.4 -17:41:13 2.6 8.50 33 PPM 259621 11:56:02.8 -25:51:32 5.3 1.50 37 PPM 259624 11:56:08.3 -23:41:45 8.2 0.76 35 PPM 259607 11:55:15.2 -24:17:31 9.6 0.15 35 9857_Hecamede 11:54:44.0 -24:23:12 15.4 35 Positions are for equinox of date
Star training set for 9857_Hecamede, (2026/03/03 08:15UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 25.41 43 4Gam Crv 12:15:48.1 -17:32:30 2.6 8.50 33 PPM 259621 11:54:42.6 -25:42:48 5.3 1.50 37 PPM 259624 11:54:48.1 -23:33:00 8.2 0.76 35 PPM 259607 11:53:55.1 -24:08:46 9.6 0.15 35 9857_Hecamede 11:53:24.0 -24:14:28 15.4 35 Positions are for J2000