RECON observing guide for 13060_91EJ_20260319013428

Occultation event with (13060) 91EJ, event index number 3463
Regions able to see the event: US

Geocentric closest approach at 2026/03/19 01:34:28 UTC

J2000 position of star is 10:29:28.6 -18:23:13
Equinox of date position of star is 10:30:44.7 -18:31:19
Star is 153 degrees from the moon. Moon is 0% illuminated.
Stellar brightness G=16.4, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.85 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 45% with SNR of 1.4 for the occulted depth (per occulted point)

Apparent velocity is 17.8 km/sec on the sky relative to the star, or, 18.4 arcsec/hr.
Position angle of asteroid motion is 115.9 degrees
The recommended exposure time corresponds to 15.1 km per image.
The 1-sigma error in the time of the event is 1.9 seconds.
The 1-sigma cross-track error in the shadow position is 19.5 km.
The sky-plane scale is 3473.6 km/arcsec.

Diameter estimates:
41.9 km assuming a 5% albedo, maximum of 2.4 sec for a central chord
17.1 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 36.1 km used for deployment plan.

Star training set for 13060_91EJ, (2026/03/19 01:34UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:09:45.9 +11:50:17  1.3 30.80 151
Alphard        09:28:52.5 -08:46:25  2.0 17.89 143
42Mu Hya       10:27:21.6 -16:58:15  3.8  1.75 154
PPM 223033     10:30:49.3 -18:22:43  8.4  0.14 153
13060_91EJ     10:30:44.7 -18:31:19 16.2       154
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 31.7 % 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
NSmith 01:39:11 -22.5 Dark Down 23.8 136.7 Low 01:35:43-01:41:43 -23.5 0.317

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 13060_91EJ, (2026/03/19 01:34UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:08:21.9 +11:58:02  1.3 30.80 151
Alphard        09:27:35.2 -08:39:30  2.0 17.89 143
42Mu Hya       10:26:05.2 -16:50:13  3.8  1.75 154
PPM 223033     10:29:33.1 -18:14:38  8.4  0.14 153
13060_91EJ     10:29:28.6 -18:23:13 16.2       153
Positions are for J2000


Created by recondetail.pro, 2025/06/19 04:50:42 MT