Occultation event with (4489) Dracius, event index number 3820
Regions able to see the event: US
Geocentric closest approach at 2026/07/01 01:56:49 UTC
J2000 position of star is 11:00:10.4 +28:07:34
Equinox of date position of star is 11:01:36.7 +27:59:00
Star is 134 degrees from the moon. Moon is 99% illuminated.
Stellar brightness G=15.9, apparent brightess of occulting body is G=14.7
Use an exposure time of 0.60 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 25% with SNR of 0.8 for the occulted depth (per occulted point)
Apparent velocity is 30.2 km/sec on the sky relative to the star, or, 27.2 arcsec/hr.
Position angle of asteroid motion is 126.6 degrees
The recommended exposure time corresponds to 18.1 km per image.
The 1-sigma error in the time of the event is 1.0 seconds.
The 1-sigma cross-track error in the shadow position is 23.2 km.
The sky-plane scale is 3990.2 km/arcsec.
Diameter estimates:
93.8 km assuming a 5% albedo, maximum of 3.1 sec for a central chord
38.3 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 76.6 km used for deployment plan.
Star training set for 4489_Dracius, (2026/07/01 01:57UT) Object RA Dec mag sep mel Regulus 10:09:46.8 +11:50:12 1.3 20.19 141 68Del Leo 11:15:30.8 +20:22:41 2.6 8.24 129 44 LMi 10:51:20.8 +27:50:00 6.0 2.27 136 PPM 100721 10:54:15.6 +27:43:27 8.1 1.65 136 PPM 100834 11:03:34.7 +27:43:49 9.9 0.50 134 PPM 100798 11:01:03.8 +28:00:39 11.3 0.12 134 4489_Dracius 11:01:36.7 +27:59:00 14.7 134 Positions are for equinox of date
Star training set for 4489_Dracius, (2026/07/01 01:57UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 20.19 141 68Del Leo 11:14:06.8 +20:31:22 2.6 8.24 129 44 LMi 10:49:53.7 +27:58:27 6.0 2.27 136 PPM 100721 10:52:48.8 +27:51:56 8.1 1.65 136 PPM 100834 11:02:08.6 +27:52:23 9.9 0.50 134 PPM 100798 10:59:37.5 +28:09:12 11.3 0.12 134 4489_Dracius 11:00:10.4 +28:07:34 14.7 134 Positions are for J2000