RECON observing guide for 4834_Thoas_20250319060401

Occultation event with (4834) Thoas, event index number 828
Regions able to see the event: US,RECON

Geocentric closest approach at 2025/03/19 06:04:01 UTC

J2000 position of star is 09:50:15.1 +46:08:19
Equinox of date position of star is 09:51:51.3 +46:01:12
Star is 101 degrees from the moon. Moon is 79% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=14.3
Use an exposure time of 2.00 seconds with the standard RECON-QHY system.
Expected flux drop is 89% with SNR of 3.5 per integration

Apparent velocity is 10.8 km/sec on the sky relative to the star, or, 12.5 arcsec/hr.
The recommended exposure time corresponds to 21.6 km per image.
The 1-sigma error in the time of the event is 4.2 seconds.
The 1-sigma cross-track error in the shadow position is 16.5 km.
The sky-plane scale is 3099.3 km/arcsec.

Diameter estimates:
87.1 km assuming a 5% albedo, aximum of 8.1 sec for a central chord
35.6 km assuming a 30% albedo, maximum of 3.3 sec for a central chord
Cross-track diameter of 87.1 km used for deployment plan.

Star training set for 4834_Thoas, (2025/03/19 06:04UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:51.3 +27:57:48  1.1 30.48 120
Merak          11:03:20.8 +56:14:48  2.4 15.10  96
PPM 051497     09:50:12.2 +45:54:08  5.1  0.31 101
PPM 051527     09:52:33.1 +45:25:46  8.2  0.60 100
PPM 051508     09:51:17.2 +46:17:33  8.8  0.29 101
4834_Thoas     09:51:51.3 +46:01:12 14.3       100
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

This table contains the target star visibility for registered RECON 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 100.0 % chance of getting at least one chord. There is a 68.6% 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
Ellensburg 06:03:59 -36.0 Dark Down 89.1 176.6 Up 06:01:15-06:07:15 91.4 0.001
Yakima 06:04:00 -36.3 Dark Down 89.5 172.7 Up 06:01:22-06:07:22 48.9 0.247
Toppenish/White Swan 06:04:00 -36.5 Dark Down 89.8 194.1 Up 06:01:23-06:07:23 22.0 0.825
The Dalles 06:04:08 -36.8 Dark Down 89.3 40.7 Up 06:01:14-06:07:14 -40.0 0.439
PNWRO 06:03:51 -37.4 Dark Down 88.9 277.7 Up 06:01:24-06:07:24 -52.8 0.176
Maupin 06:04:08 -37.1 Dark Down 89.0 22.2 Up 06:01:23-06:07:23 -86.7 0.001

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 4834_Thoas, (2025/03/19 06:04UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.8 +28:01:33  1.1 30.48 120
Merak          11:01:50.7 +56:22:58  2.4 15.10  96
PPM 051497     09:48:35.9 +46:01:13  5.1  0.31 101
PPM 051527     09:50:57.4 +45:32:54  8.2  0.60 100
PPM 051508     09:49:40.8 +46:24:40  8.8  0.29 101
4834_Thoas     09:50:15.1 +46:08:19 14.3       101
Positions are for J2000


Created by recondetail.pro, 2025/02/18 10:03:08 MT