Occultation event with (16974) Iphthime, event index number 699
Regions able to see the event: SAmericaS
Geocentric closest approach at 2025/02/23 01:41:52 UTC
J2000 position of star is 08:39:45.1 +00:12:04
Equinox of date position of star is 08:41:02.5 +00:06:40
Star is 134 degrees from the moon. Moon is 28% illuminated.
Stellar brightness G=15.0, apparent brightess of occulting body is G=15.0
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
Expected flux drop is 49% with SNR of 9.5 per integration
Apparent velocity is 15.5 km/sec on the sky relative to the star, or, 17.4 arcsec/hr.
The recommended exposure time corresponds to 14.8 km per image.
The 1-sigma error in the time of the event is 2.4 seconds.
The 1-sigma cross-track error in the shadow position is 17.4 km.
The sky-plane scale is 3214.3 km/arcsec.
Diameter estimates:
61.7 km assuming a 5% albedo, aximum of 4.0 sec for a central chord
25.2 km assuming a 30% albedo, maximum of 1.6 sec for a central chord
Cross-track diameter of 61.7 km used for deployment plan.
Star training set for 16974_Iphthime, (2025/02/23 01:42UT) Object RA Dec mag sep mel Regulus 10:09:42.5 +11:50:36 1.3 24.94 121 Alphard 09:28:49.4 -08:46:08 2.0 14.85 119 PPM 177501 08:35:17.9 -02:14:21 6.4 2.75 133 PPM 154788 08:39:38.0 +00:36:06 8.0 0.60 134 PPM 154809 08:40:37.1 +00:32:49 9.9 0.45 134 PPM 154804 08:40:31.0 +00:24:55 10.4 0.33 134 16974_Iphthime 08:41:02.5 +00:06:40 15.0 133 Positions are for equinox of date
This table contains the target star visibility for registered SAmericaS 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 16974_Iphthime, (2025/02/23 01:42UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 24.94 121 Alphard 09:27:35.2 -08:39:30 2.0 14.85 119 PPM 177501 08:34:01.6 -02:09:06 6.4 2.75 133 PPM 154788 08:38:20.3 +00:41:28 8.0 0.60 134 PPM 154809 08:39:19.5 +00:38:13 9.9 0.45 134 PPM 154804 08:39:13.4 +00:30:18 10.4 0.33 134 16974_Iphthime 08:39:45.1 +00:12:04 15.0 134 Positions are for J2000