Occultation event with (3451) Mentor, event index number 4496
Regions able to see the event: US,SAmericaN,UVa
Geocentric closest approach at 2026/10/27 10:00:07 UTC
J2000 position of star is 07:07:59.7 -03:35:22
Equinox of date position of star is 07:09:20.0 -03:38:01
Star is 64 degrees from the moon. Moon is 98% illuminated.
Stellar brightness G=14.6, apparent brightess of occulting body is G=14.2
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 10.0 per integration for unocculted signal
Expected flux drop is 41% with SNR of 4.1 for the occulted depth (per occulted point)
Apparent velocity is 11.5 km/sec on the sky relative to the star, or, 11.0 arcsec/hr.
Position angle of asteroid motion is 167.7 degrees
The recommended exposure time corresponds to 8.0 km per image.
The 1-sigma error in the time of the event is 3.2 seconds.
The 1-sigma cross-track error in the shadow position is 8.8 km.
The sky-plane scale is 3756.5 km/arcsec.
Diameter estimates:
122.5 km assuming a 5% albedo, maximum of 10.7 sec for a central chord
50.0 km assuming a 30% albedo, maximum of 4.4 sec for a central chord
Cross-track diameter of 126.3 km used for deployment plan.
Star training set for 3451_Mentor, (2026/10/27 10:00UT) Object RA Dec mag sep mel Sirius 06:46:19.8 -16:45:15 -1.5 14.28 66 2Bet CMa 06:23:52.9 -17:58:16 2.0 18.15 63 20 Mon 07:11:33.6 -04:16:52 4.9 0.85 65 PPM 189946 07:09:07.4 -03:24:54 7.9 0.22 64 3451_Mentor 07:09:20.0 -03:38:01 14.2 65 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 50.3 % 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Getrost | 09:53:35 | -23.1 | Dark | Up | 45.1 | 173.1 | Up | 09:51:13-09:57:13 | -54.3 | 0.503 |
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 0.1 % 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| Crozet | 09:54:01 | -20.5 | Dark | Up | 48.3 | 177.9 | Up | 09:51:05-09:57:05 | 176.1 | 0.000 | Lynchburg | 09:54:05 | -20.9 | Dark | Up | 49.0 | 177.2 | Up | 09:50:57-09:56:57 | 123.2 | 0.000 | Green_Bank | 09:53:57 | -21.4 | Dark | Up | 47.9 | 176.2 | Up | 09:51:06-09:57:06 | 82.4 | 0.001 |
Star training set for 3451_Mentor, (2026/10/27 10:00UT) Object RA Dec mag sep mel Sirius 06:45:07.9 -16:43:29 -1.5 14.28 66 2Bet CMa 06:22:42.0 -17:57:21 2.0 18.15 63 20 Mon 07:10:13.7 -04:14:08 4.9 0.85 65 PPM 189946 07:07:47.0 -03:22:16 7.9 0.22 64 3451_Mentor 07:07:59.7 -03:35:22 14.2 64 Positions are for J2000