Occultation event with (15398) 97UZ23, event index number 3603
Regions able to see the event: US,SAmericaN,NMexico,SMexico
Geocentric closest approach at 2026/04/09 03:35:59 UTC
J2000 position of star is 11:44:36.9 -03:47:12
Equinox of date position of star is 11:45:57.6 -03:55:57
Star is 99 degrees from the moon. Moon is 60% illuminated.
Stellar brightness G=11.4, apparent brightess of occulting body is G=15.6
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 30.7 per integration for unocculted signal
Expected flux drop is 98% with SNR of 30.1 for the occulted depth (per occulted point)
Apparent velocity is 17.6 km/sec on the sky relative to the star, or, 21.4 arcsec/hr.
Position angle of asteroid motion is 137.5 degrees
The recommended exposure time corresponds to 2.1 km per image.
The 1-sigma error in the time of the event is 1.3 seconds.
The 1-sigma cross-track error in the shadow position is 25.1 km.
The sky-plane scale is 2955.5 km/arcsec.
Diameter estimates:
39.8 km assuming a 5% albedo, maximum of 2.3 sec for a central chord
16.2 km assuming a 30% albedo, maximum of 0.9 sec for a central chord
Cross-track diameter of 35.5 km used for deployment plan.
Star training set for 15398_97UZ23, (2026/04/09 03:36UT) Object RA Dec mag sep mel Spica 13:26:34.9 -11:17:51 1.0 25.98 74 4Gam Crv 12:17:09.7 -17:41:16 2.6 15.74 86 PPM 194890 11:52:22.9 -05:28:46 5.6 2.23 97 PPM 194752 11:44:10.4 -03:41:29 8.0 0.51 100 PPM 194774 11:45:39.9 -03:46:52 9.8 0.17 99 15398_97UZ23 11:45:57.6 -03:55:57 15.6 99 Positions are for equinox of date
This table contains the target star visibility for registered US sites that are relevant for this occultation. This list has been filtered to only those sites that can see the field and are within range of the shadow given the uncertainties. The observing time range has been calculated to cover the time of the event at each site with allowances for the event timing uncertainty plus time for obtaining a pre and post event baseline lightcurve. This set of stations has a 0.0 % chance of getting at least one chord. There is a 0.0% chance of 2 or more chords assuming clear weather for all.
| Site Name | Site mid-time (UT) |
Sun alt (deg) |
Sky | Moon | Star alt (deg) |
Star az (deg) |
Target | Observing Time | Xtrack (km) |
Prob |
|---|---|---|---|---|---|---|---|---|---|---|
Star training set for 15398_97UZ23, (2026/04/09 03:36UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 25.98 74 4Gam Crv 12:15:48.1 -17:32:30 2.6 15.74 86 PPM 194890 11:51:02.3 -05:20:00 5.6 2.23 97 PPM 194752 11:42:49.8 -03:32:44 8.0 0.51 100 PPM 194774 11:44:19.3 -03:38:07 9.8 0.17 99 15398_97UZ23 11:44:36.9 -03:47:12 15.6 99 Positions are for J2000