Occultation event with (30705) Idaios, event index number 1321
Regions able to see the event: US,RECON,SwRI-CO,UVa
Geocentric closest approach at 2025/09/29 06:47:38 UTC
J2000 position of star is 01:31:26.7 +07:44:12
Equinox of date position of star is 01:32:47.7 +07:52:07
Star is 115 degrees from the moon. Moon is 43% illuminated.
Stellar brightness G=12.6, apparent brightess of occulting body is G=15.0
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 14.6 per integration for unocculted signal
Expected flux drop is 90% with SNR of 13.2 for the occulted depth (per occulted point)
Apparent velocity is 16.0 km/sec on the sky relative to the star, or, 20.3 arcsec/hr.
Position angle of asteroid motion is 84.6 degrees
The recommended exposure time corresponds to 1.9 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 20.3 km.
The sky-plane scale is 2840.5 km/arcsec.
Diameter estimates:
48.8 km assuming a 5% albedo, aximum of 3.0 sec for a central chord
19.9 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 44.5 km used for deployment plan.
Star training set for 30705_Idaios, (2025/09/29 06:48UT) Object RA Dec mag sep mel Aldebaran 04:37:24.1 +16:33:32 0.8 45.83 159 6Bet Ari 01:56:04.1 +20:55:58 2.6 14.22 126 PPM 144653 01:30:23.9 +07:25:34 6.4 0.74 115 PPM 144733 01:34:39.4 +08:20:23 7.2 0.66 116 PPM 144696 01:32:29.9 +07:49:40 9.7 0.08 115 30705_Idaios 01:32:47.7 +07:52:07 15.0 116 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 29.8 % chance of getting at least one chord. There is a 1.1% 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Naylor Obs | 06:46:31 | -45.1 | Dark | Down | 56.3 | 198.4 | Up | 06:43:58-06:49:58 | 61.8 | 0.018 | Ryan Obs | 06:46:28 | -45.0 | Dark | Down | 56.5 | 199.6 | Up | 06:45:21-06:51:21 | 30.0 | 0.290 | Patrick | 06:49:10 | -57.5 | Dark | Down | 57.9 | 144.0 | Up | 06:43:36-06:49:36 | -168.1 | 0.000 |
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 7.5 % chance of getting at least one chord. There is a 4.4% 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| North Las Vegas | 06:49:53 | -54.9 | Dark | Down | 52.1 | 132.2 | Up | 06:46:36-06:52:36 | 70.0 | 0.006 | Laughlin/Bullhead City | 06:49:53 | -56.2 | Dark | Down | 53.3 | 132.0 | Up | 06:46:52-06:52:52 | -49.0 | 0.069 | Kingman/Dolan Springs | 06:49:50 | -56.3 | Dark | Down | 53.6 | 132.6 | Up | 06:46:35-06:52:35 | -53.2 | 0.045 | Wildwood | 06:50:15 | -56.0 | Dark | Down | 51.4 | 126.0 | Up | 06:46:34-06:52:34 | -97.3 | 0.000 | Lake Havasu City | 06:49:53 | -56.9 | Dark | Down | 53.9 | 131.6 | Up | 06:45:35-06:51:35 | -116.2 | 0.000 | Idyllwild | 06:50:06 | -56.9 | Dark | Down | 52.9 | 127.9 | Up | 06:47:17-06:53:17 | -156.5 | 0.000 |
This table contains the target star visibility for registered SwRI-CO 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 UVa 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Charlottesville | 06:46:39 | -47.5 | Dark | Down | 58.7 | 196.6 | Up | 06:43:39-06:49:39 | -130.5 | 0.000 |
Star training set for 30705_Idaios, (2025/09/29 06:48UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 45.83 159 6Bet Ari 01:54:38.6 +20:48:26 2.6 14.22 126 PPM 144653 01:29:03.0 +07:17:37 6.4 0.74 115 PPM 144733 01:33:18.2 +08:12:30 7.2 0.66 116 PPM 144696 01:31:08.9 +07:41:45 9.7 0.08 115 30705_Idaios 01:31:26.7 +07:44:12 15.0 115 Positions are for J2000