Occultation event with (11887) Echemmon, event index number 3392
Regions able to see the event: Europe
Geocentric closest approach at 2026/03/10 18:23:05 UTC
J2000 position of star is 03:06:19.2 +18:51:26
Equinox of date position of star is 03:07:48.5 +18:57:26
Star is 156 degrees from the moon. Moon is 56% illuminated.
Stellar brightness G=15.3, apparent brightess of occulting body is G=16.4
Use an exposure time of 0.25 seconds with the standard RECON-QHY system.
SNR of 3.3 per integration for unocculted signal
Expected flux drop is 75% with SNR of 2.5 for the occulted depth (per occulted point)
Apparent velocity is 28.0 km/sec on the sky relative to the star, or, 25.9 arcsec/hr.
Position angle of asteroid motion is 86.8 degrees
The recommended exposure time corresponds to 7.0 km per image.
The 1-sigma error in the time of the event is 0.1 seconds.
The 1-sigma cross-track error in the shadow position is 36.1 km.
The sky-plane scale is 3887.5 km/arcsec.
Diameter estimates:
40.7 km assuming a 5% albedo, maximum of 1.5 sec for a central chord
16.6 km assuming a 30% albedo, maximum of 0.6 sec for a central chord
Cross-track diameter of 31.2 km used for deployment plan.
Star training set for 11887_Echemmon, (2026/03/10 18:23UT) Object RA Dec mag sep mel Aldebaran 04:37:25.6 +16:33:35 0.8 21.46 169 Hamal 02:08:39.4 +23:35:06 2.0 14.53 144 57Del Ari 03:13:07.9 +19:49:26 4.3 1.53 157 PPM 118805 03:07:16.3 +18:16:48 8.5 0.69 155 PPM 118822 03:08:40.0 +19:27:47 8.9 0.54 156 PPM 118804 03:07:08.7 +18:47:31 10.8 0.23 156 11887_Echemmon 03:07:48.5 +18:57:26 16.4 156 Positions are for equinox of date
Star training set for 11887_Echemmon, (2026/03/10 18:23UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 21.46 169 Hamal 02:07:10.8 +23:27:41 2.0 14.53 144 57Del Ari 03:11:38.0 +19:43:36 4.3 1.53 157 PPM 118805 03:05:47.4 +18:10:47 8.5 0.69 155 PPM 118822 03:07:10.4 +19:21:49 8.9 0.54 156 PPM 118804 03:05:39.6 +18:41:30 10.8 0.23 156 11887_Echemmon 03:06:19.2 +18:51:26 16.4 156 Positions are for J2000