Occultation event with (1437) Diomedes, event index number 3145
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/01/14 07:21:07 UTC
J2000 position of star is 13:31:19.4 -29:32:45
Equinox of date position of star is 13:32:47.2 -29:40:45
Star is 34 degrees from the moon. Moon is 18% illuminated.
Stellar brightness G=16.3, apparent brightess of occulting body is G=13.9
Use an exposure time of 1.45 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 10% with SNR of 0.3 for the occulted depth (per occulted point)
Apparent velocity is 20.0 km/sec on the sky relative to the star, or, 18.5 arcsec/hr.
Position angle of asteroid motion is 144.7 degrees
The recommended exposure time corresponds to 29.1 km per image.
The 1-sigma error in the time of the event is 1.7 seconds.
The 1-sigma cross-track error in the shadow position is 4.7 km.
The sky-plane scale is 3894.2 km/arcsec.
Diameter estimates:
140.6 km assuming a 5% albedo, maximum of 7.0 sec for a central chord
57.4 km assuming a 30% albedo, maximum of 2.9 sec for a central chord
Cross-track diameter of 117.8 km used for deployment plan.
Star training set for 1437_Diomedes, (2026/01/14 07:21UT) Object RA Dec mag sep mel Spica 13:26:34.1 -11:17:47 1.0 18.44 40 Iot Cen 13:22:04.2 -36:50:56 2.8 7.51 36 PPM 261770 13:34:03.4 -28:49:34 5.7 0.90 33 PPM 261768 13:34:02.2 -29:41:54 6.9 0.27 33 1437_Diomedes 13:32:47.2 -29:40:45 13.9 33 Positions are for equinox of date
Star training set for 1437_Diomedes, (2026/01/14 07:21UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 18.44 40 Iot Cen 13:20:35.1 -36:42:46 2.8 7.51 36 PPM 261770 13:32:35.7 -28:41:35 5.7 0.90 33 PPM 261768 13:32:34.3 -29:33:55 6.9 0.27 33 1437_Diomedes 13:31:19.4 -29:32:45 13.9 34 Positions are for J2000