Occultation event with (1437) Diomedes, event index number 3236
Regions able to see the event: SAmericaN,SAmericaS
Geocentric closest approach at 2026/02/11 04:47:13 UTC
J2000 position of star is 13:35:35.6 -32:03:15
Equinox of date position of star is 13:37:04.8 -32:11:13
Star is 38 degrees from the moon. Moon is 35% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=13.7
Use an exposure time of 2.00 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 8% with SNR of 0.2 for the occulted depth (per occulted point)
Apparent velocity is 11.5 km/sec on the sky relative to the star, or, 11.5 arcsec/hr.
Position angle of asteroid motion is 5.3 degrees
The recommended exposure time corresponds to 23.0 km per image.
The 1-sigma error in the time of the event is 2.6 seconds.
The 1-sigma cross-track error in the shadow position is 18.7 km.
The sky-plane scale is 3598.4 km/arcsec.
Diameter estimates:
140.6 km assuming a 5% albedo, maximum of 12.2 sec for a central chord
57.4 km assuming a 30% albedo, maximum of 5.0 sec for a central chord
Cross-track diameter of 117.8 km used for deployment plan.
Star training set for 1437_Diomedes, (2026/02/11 04:47UT) Object RA Dec mag sep mel Spica 13:26:34.4 -11:17:48 1.0 21.03 47 Iot Cen 13:22:04.5 -36:50:57 2.8 5.59 41 PPM 291555 13:36:13.1 -33:26:38 6.5 1.27 39 PPM 291564 13:36:41.3 -32:20:44 7.1 0.18 39 PPM 291578 13:37:07.0 -32:09:02 9.7 0.04 38 1437_Diomedes 13:37:04.8 -32:11:13 13.7 38 Positions are for equinox of date
Star training set for 1437_Diomedes, (2026/02/11 04:47UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 21.03 47 Iot Cen 13:20:35.1 -36:42:46 2.8 5.59 41 PPM 291555 13:34:43.5 -33:18:40 6.5 1.27 39 PPM 291564 13:35:12.1 -32:12:46 7.1 0.18 39 PPM 291578 13:35:37.7 -32:01:04 9.7 0.04 38 1437_Diomedes 13:35:35.6 -32:03:15 13.7 38 Positions are for J2000