Occultation event with (12444) Prothoon, event index number 3844
Regions able to see the event: Australia
Geocentric closest approach at 2026/07/13 19:10:39 UTC
J2000 position of star is 03:58:51.4 +10:46:29
Equinox of date position of star is 04:00:18.9 +10:50:56
Star is 45 degrees from the moon. Moon is 1% illuminated.
Stellar brightness G=11.5, apparent brightess of occulting body is G=15.9
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 28.0 per integration for unocculted signal
Expected flux drop is 98% with SNR of 27.5 for the occulted depth (per occulted point)
Apparent velocity is 30.6 km/sec on the sky relative to the star, or, 25.1 arcsec/hr.
Position angle of asteroid motion is 96.5 degrees
The recommended exposure time corresponds to 3.7 km per image.
The 1-sigma error in the time of the event is 0.4 seconds.
The 1-sigma cross-track error in the shadow position is 29.9 km.
The sky-plane scale is 4388.2 km/arcsec.
Diameter estimates:
62.2 km assuming a 5% albedo, maximum of 2.0 sec for a central chord
25.4 km assuming a 30% albedo, maximum of 0.8 sec for a central chord
Cross-track diameter of 63.8 km used for deployment plan.
Star training set for 12444_Prothoon, (2026/07/13 19:11UT) Object RA Dec mag sep mel Aldebaran 04:37:26.8 +16:33:38 0.8 10.67 34 Menkar 03:03:40.2 +04:11:32 2.5 15.53 60 PPM 119523 04:01:07.9 +10:24:15 6.5 0.49 45 PPM 119506 04:00:04.9 +11:06:06 8.5 0.26 45 12444_Prothoon 04:00:18.9 +10:50:56 15.9 45 Positions are for equinox of date
Star training set for 12444_Prothoon, (2026/07/13 19:11UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 10.67 34 Menkar 03:02:16.8 +04:05:21 2.5 15.53 60 PPM 119523 03:59:40.7 +10:19:50 6.5 0.49 45 PPM 119506 03:58:37.4 +11:01:39 8.5 0.26 45 12444_Prothoon 03:58:51.4 +10:46:29 15.9 45 Positions are for J2000