Occultation event with (5244) Amphilochos, event index number 985
Regions able to see the event: Australia
Geocentric closest approach at 2025/05/18 12:57:46 UTC
J2000 position of star is 09:43:26.8 +08:08:46
Equinox of date position of star is 09:44:47.5 +08:01:44
Star is 157 degrees from the moon. Moon is 70% illuminated.
Stellar brightness G=13.7, apparent brightess of occulting body is G=16.3
Use an exposure time of 0.20 seconds with the standard RECON-QHY system.
SNR of 9.7 per integration for unocculted signal
Expected flux drop is 92% with SNR of 8.9 for the occulted depth (per occulted point)
Apparent velocity is 13.6 km/sec on the sky relative to the star, or, 12.8 arcsec/hr.
Position angle of asteroid motion is 351.0 degrees
The recommended exposure time corresponds to 2.7 km per image.
The 1-sigma error in the time of the event is 3.7 seconds.
The 1-sigma cross-track error in the shadow position is 17.3 km.
The sky-plane scale is 3821.5 km/arcsec.
Diameter estimates:
45.9 km assuming a 5% albedo, aximum of 3.4 sec for a central chord
18.8 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 45.9 km used for deployment plan.
Star training set for 5244_Amphilochos, (2025/05/18 12:58UT) Object RA Dec mag sep mel Regulus 10:09:43.3 +11:50:32 1.3 7.23 154 PPM 156172 09:47:30.3 +06:35:25 5.8 1.59 155 PPM 156131 09:45:04.5 +07:50:07 8.1 0.21 157 5244_Amphiloch 09:44:47.5 +08:01:44 16.3 156 Positions are for equinox of date
Star training set for 5244_Amphilochos, (2025/05/18 12:58UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 7.23 154 PPM 156172 09:46:10.1 +06:42:30 5.8 1.59 155 PPM 156131 09:43:43.9 +07:57:09 8.1 0.21 157 5244_Amphiloch 09:43:26.8 +08:08:46 16.3 157 Positions are for J2000