RECON observing guide for 17171_99NB38_20250613093954

Occultation event with (17171) 99NB38, event index number 1054
Regions able to see the event: SAmericaN

Geocentric closest approach at 2025/06/13 09:39:54 UTC

J2000 position of star is 02:28:28.2 +37:38:48
Equinox of date position of star is 02:30:02.3 +37:45:33
Star is 120 degrees from the moon. Moon is 96% illuminated.
Stellar brightness G=16.1, apparent brightess of occulting body is G=16.3
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 55% with SNR of 1.8 for the occulted depth (per occulted point)

Apparent velocity is 37.7 km/sec on the sky relative to the star, or, 32.3 arcsec/hr.
The recommended exposure time corresponds to 22.6 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 31.4 km.
The sky-plane scale is 4201.8 km/arcsec.

Diameter estimates:
46.1 km assuming a 5% albedo, aximum of 1.2 sec for a central chord
18.8 km assuming a 30% albedo, maximum of 0.5 sec for a central chord
Cross-track diameter of 46.1 km used for deployment plan.

Star training set for 17171_99NB38, (2025/06/13 09:40UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:23.0 +16:33:30  0.8 35.08 142
57Gam1And      02:05:28.4 +42:27:02  2.3  6.64 117
14 Tri         02:33:39.9 +36:15:31  5.1  1.67 120
PPM 067382     02:30:41.7 +37:26:31  7.0  0.34 120
PPM 067352     02:29:08.8 +37:34:55 10.0  0.25 120
17171_99NB38   02:30:02.3 +37:45:33 16.3       120
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 17171_99NB38, (2025/06/13 09:40UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.4 +16:30:29  0.8 35.08 142
57Gam1And      02:03:54.1 +42:19:46  2.3  6.64 117
14 Tri         02:32:06.3 +36:08:50  5.1  1.67 120
PPM 067382     02:29:07.6 +37:19:46  7.0  0.34 120
PPM 067352     02:27:34.8 +37:28:08 10.0  0.25 120
17171_99NB38   02:28:28.2 +37:38:48 16.3       120
Positions are for J2000


Created by recondetail.pro, 2025/02/28 09:19:41 MT