Occultation event with (4543) Phoinix, event index number 28
Regions able to see the event: US,RECON
Geocentric closest approach at 2025/03/31 07:41:55 UTC
J2000 position of star is 11:22:04.3 -06:13:21
Equinox of date position of star is 11:23:21.4 -06:21:40
Star is 136 degrees from the moon. Moon is 5% illuminated.
Stellar brightness G=15.5, apparent brightess of occulting body is G=14.8
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
SNR of 6.0 per integration for unocculted signal
Expected flux drop is 35% with SNR of 2.1 for the occulted depth (per occulted point)
Apparent velocity is 16.6 km/sec on the sky relative to the star, or, 18.5 arcsec/hr.
Position angle of asteroid motion is 0.0 degrees
The recommended exposure time corresponds to 15.8 km per image.
The 1-sigma error in the time of the event is 0.1 seconds.
The 1-sigma cross-track error in the shadow position is 26.4 km.
The sky-plane scale is 3232.6 km/arcsec.
Diameter estimates:
66.4 km assuming a 5% albedo, aximum of 4.0 sec for a central chord
27.1 km assuming a 30% albedo, maximum of 1.6 sec for a central chord
Cross-track diameter of 66.4 km used for deployment plan.
Star training set for 4543_Phoinix, (2025/03/31 07:42UT) Object RA Dec mag sep mel Regulus 10:09:42.8 +11:50:34 1.3 25.82 113 4Gam Crv 12:17:06.5 -17:40:55 2.6 17.33 152 PPM 194312 11:18:15.0 -07:16:22 6.1 1.56 136 PPM 194381 11:23:03.9 -05:51:26 8.1 0.51 136 PPM 194395 11:23:50.3 -06:12:55 9.7 0.19 137 4543_Phoinix 11:23:21.4 -06:21:40 14.8 137 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 32.3 % chance of getting at least one chord. There is a 0.5% 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Hodapp | 07:39:59 | -48.9 | Dark | Down | 37.0 | 229.1 | Low | 07:36:24-07:42:24 | 101.3 | 0.003 | Cobble | 07:40:01 | -49.1 | Dark | Down | 37.3 | 228.7 | Up | 07:36:59-07:42:59 | 94.0 | 0.007 | Patrick | 07:40:50 | -50.0 | Dark | Down | 41.3 | 217.7 | Low | 07:36:20-07:42:20 | 40.9 | 0.318 |
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 89.4% 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Burney | 07:42:19 | -44.4 | Dark | Down | 41.6 | 196.5 | Up | 07:38:31-07:44:31 | 91.0 | 0.009 | Gimple | 07:42:14 | -45.2 | Dark | Down | 42.1 | 197.7 | Up | 07:38:28-07:44:28 | 60.2 | 0.116 | Reno | 07:42:07 | -45.9 | Dark | Down | 42.4 | 199.2 | Up | 07:38:38-07:44:38 | 45.1 | 0.259 | Quincy | 07:42:14 | -45.4 | Dark | Down | 42.3 | 197.6 | Up | 07:38:30-07:44:30 | 44.5 | 0.265 | Yerington | 07:42:03 | -46.5 | Dark | Down | 42.8 | 200.2 | Up | 07:38:25-07:44:25 | 22.7 | 0.557 | Carson City | 07:42:07 | -46.2 | Dark | Down | 42.7 | 199.3 | Up | 07:38:48-07:44:48 | 21.0 | 0.577 | Gardnerville | 07:42:06 | -46.5 | Dark | Down | 43.0 | 199.5 | Up | 07:39:14-07:45:14 | 5.2 | 0.710 | Hawthorne | 07:41:59 | -47.0 | Dark | Down | 43.1 | 201.0 | Up | 07:39:30-07:45:30 | 3.3 | 0.716 | Lee Vining | 07:42:00 | -47.5 | Dark | Down | 43.7 | 200.6 | Up | 07:39:30-07:45:30 | -47.5 | 0.237 | Bishop | 07:41:57 | -48.0 | Dark | Down | 44.0 | 201.4 | Up | 07:39:29-07:45:29 | -69.0 | 0.064 | Swift | 07:42:15 | -46.6 | Dark | Down | 43.8 | 196.9 | Up | 07:39:30-07:45:30 | -72.6 | 0.048 |
Star training set for 4543_Phoinix, (2025/03/31 07:42UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 25.82 113 4Gam Crv 12:15:48.1 -17:32:30 2.6 17.33 152 PPM 194312 11:16:58.2 -07:08:05 6.1 1.56 136 PPM 194381 11:21:46.8 -05:43:07 8.1 0.51 136 PPM 194395 11:22:33.2 -06:04:35 9.7 0.19 137 4543_Phoinix 11:22:04.3 -06:13:21 14.8 136 Positions are for J2000