Occultation event with (38050) Bias, event index number 999
Regions able to see the event: Senegal
Geocentric closest approach at 2025/05/24 21:34:29 UTC
J2000 position of star is 08:29:58.1 -09:07:10
Equinox of date position of star is 08:31:11.9 -09:12:20
Star is 100 degrees from the moon. Moon is 7% illuminated.
Stellar brightness G=14.7, apparent brightess of occulting body is G=15.5
Use an exposure time of 0.60 seconds with the standard RECON-QHY system.
SNR of 9.6 per integration for unocculted signal
Expected flux drop is 69% with SNR of 6.6 for the occulted depth (per occulted point)
Apparent velocity is 26.1 km/sec on the sky relative to the star, or, 24.4 arcsec/hr.
Position angle of asteroid motion is 11.6 degrees
The recommended exposure time corresponds to 15.7 km per image.
The 1-sigma error in the time of the event is 1.4 seconds.
The 1-sigma cross-track error in the shadow position is 15.3 km.
The sky-plane scale is 3849.1 km/arcsec.
Diameter estimates:
63.4 km assuming a 5% albedo, aximum of 2.4 sec for a central chord
25.9 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 63.4 km used for deployment plan.
Star training set for 38050_Bias, (2025/05/24 21:34UT) Object RA Dec mag sep mel Sirius 06:46:16.0 -16:45:09 -1.5 26.62 78 Alphard 09:28:50.1 -08:46:12 2.0 14.24 114 PPM 191380 08:29:33.7 -08:54:08 6.5 0.51 100 PPM 191396 08:30:29.5 -09:14:35 9.2 0.18 100 38050_Bias 08:31:11.9 -09:12:20 15.5 101 Positions are for equinox of date
Star training set for 38050_Bias, (2025/05/24 21:34UT) Object RA Dec mag sep mel Sirius 06:45:07.9 -16:43:28 -1.5 26.62 78 Alphard 09:27:35.2 -08:39:30 2.0 14.24 114 PPM 191380 08:28:19.8 -08:49:00 6.5 0.51 100 PPM 191396 08:29:15.7 -09:09:25 9.2 0.18 100 38050_Bias 08:29:58.1 -09:07:10 15.5 100 Positions are for J2000