RECON observing guide for 12126_99RM11_20251121184112

Occultation event with (12126) 99RM11, event index number 1564
Regions able to see the event: SAfrica

Geocentric closest approach at 2025/11/21 18:41:12 UTC

J2000 position of star is 02:58:05.5 +19:07:43
Equinox of date position of star is 02:59:33.6 +19:13:51
Star is 152 degrees from the moon. Moon is 2% illuminated.
Stellar brightness G=11.9, apparent brightess of occulting body is G=15.1
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 22.2 per integration for unocculted signal
Expected flux drop is 95% with SNR of 21.1 for the occulted depth (per occulted point)

Apparent velocity is 17.2 km/sec on the sky relative to the star, or, 19.0 arcsec/hr.
Position angle of asteroid motion is 73.5 degrees
The recommended exposure time corresponds to 2.1 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 24.4 km.
The sky-plane scale is 3247.5 km/arcsec.

Diameter estimates:
56.5 km assuming a 5% albedo, aximum of 3.3 sec for a central chord
23.1 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 53.2 km used for deployment plan.

Star training set for 12126_99RM11, (2025/11/21 18:41UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:24.6 +16:33:33  0.8 23.41 168
Hamal          02:08:38.3 +23:35:01  2.0 12.62 142
46Rho3Ari      02:57:54.1 +18:07:29  5.6  1.17 151
PPM 118751     03:02:39.3 +19:30:14  8.5  0.78 152
PPM 118707     02:59:52.0 +19:19:53  8.8  0.12 152
12126_99RM11   02:59:33.6 +19:13:51 15.1       152
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, (2025/11/21 18:41UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.4 +16:30:29  0.8 23.41 168
Hamal          02:07:10.8 +23:27:41  2.0 12.62 142
46Rho3Ari      02:56:26.6 +18:01:18  5.6  1.17 151
PPM 118751     03:01:10.9 +19:24:10  8.5  0.78 152
PPM 118707     02:58:23.8 +19:13:45  8.8  0.12 152
12126_99RM11   02:58:05.5 +19:07:43 15.1       152
Positions are for J2000


Created by recondetail.pro, 2025/05/21 22:13:25 MT