RECON observing guide for 12126_99RM11_20261205232452

Occultation event with (12126) 99RM11, event index number 5061
Regions able to see the event: SAmericaN

Geocentric closest approach at 2026/12/05 23:24:52 UTC

J2000 position of star is 04:57:28.4 +25:07:00
Equinox of date position of star is 04:59:07.4 +25:09:24
Star is 144 degrees from the moon. Moon is 9% illuminated.
Stellar brightness G=14.6, apparent brightess of occulting body is G=15.3
Use an exposure time of 0.60 seconds with the standard RECON-QHY system.
SNR of 9.8 per integration for unocculted signal
Expected flux drop is 66% with SNR of 6.4 for the occulted depth (per occulted point)

Apparent velocity is 19.0 km/sec on the sky relative to the star, or, 19.1 arcsec/hr.
Position angle of asteroid motion is 84.0 degrees
The recommended exposure time corresponds to 11.4 km per image.
The 1-sigma error in the time of the event is 0.3 seconds.
The 1-sigma cross-track error in the shadow position is 28.3 km.
The sky-plane scale is 3585.3 km/arcsec.

Diameter estimates:
56.5 km assuming a 5% albedo, maximum of 3.0 sec for a central chord
23.1 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 53.2 km used for deployment plan.

Star training set for 12126_99RM11, (2026/12/05 23:25UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:28.1 +16:33:40  0.8  9.97 148
Alnath         05:27:59.8 +28:37:39  1.6  7.31 137
98 Tau         04:59:48.5 +25:05:22  5.8  0.17 144
PPM 093905     04:57:54.2 +24:37:58  7.0  0.59 144
98 Tau         04:59:48.5 +25:05:22  5.8  0.17 144
12126_99RM11   04:59:07.4 +25:09:24 15.3       143
Positions are for equinox of date

Azimuth is measured in degrees eastward from north. North is at an azimuth of 0, due East is at an azimuth of 90 degrees, due South is 180, and due West is 270.

Star training set for 12126_99RM11, (2026/12/05 23:25UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.4 +16:30:29  0.8  9.97 148
Alnath         05:26:17.6 +28:36:22  1.6  7.31 137
98 Tau         04:58:09.4 +25:03:00  5.8  0.17 144
PPM 093905     04:56:15.5 +24:35:32  7.0  0.59 144
98 Tau         04:58:09.4 +25:03:00  5.8  0.17 144
12126_99RM11   04:57:28.4 +25:07:00 15.3       144
Positions are for J2000


Created by recondetail.pro, 2025/06/21 15:00:52 MT