RECON observing guide for 9857_Hecamede_20260308015247

Occultation event with (9857) Hecamede, event index number 3373
Regions able to see the event: SAmericaN

Geocentric closest approach at 2026/03/08 01:52:47 UTC

J2000 position of star is 11:50:58.1 -24:12:03
Equinox of date position of star is 11:52:18.1 -24:20:48
Star is 37 degrees from the moon. Moon is 80% illuminated.
Stellar brightness G=14.9, apparent brightess of occulting body is G=15.4
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 9.2 per integration for unocculted signal
Expected flux drop is 61% with SNR of 5.6 for the occulted depth (per occulted point)

Apparent velocity is 15.8 km/sec on the sky relative to the star, or, 18.1 arcsec/hr.
Position angle of asteroid motion is 96.4 degrees
The recommended exposure time corresponds to 11.8 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 27.2 km.
The sky-plane scale is 3141.6 km/arcsec.

Diameter estimates:
51.5 km assuming a 5% albedo, maximum of 3.3 sec for a central chord
21.0 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 49.5 km used for deployment plan.

Star training set for 9857_Hecamede, (2026/03/08 01:53UT)
Object            RA         Dec     mag  sep  mel
Spica          13:26:34.6 -11:17:50  1.0 25.89  17
4Gam Crv       12:17:09.4 -17:41:14  2.6  8.83  31
PPM 259621     11:56:02.8 -25:51:32  5.3  1.73  36
PPM 259481     11:49:50.2 -25:13:53  8.3  1.05  37
PPM 259543     11:52:35.0 -24:26:44  9.4  0.12  37
9857_Hecamede  11:52:18.1 -24:20:48 15.4        36
Positions are for equinox of date

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 9857_Hecamede, (2026/03/08 01:53UT)
Object            RA         Dec     mag  sep  mel
Spica          13:25:11.5 -11:09:41  1.0 25.89  17
4Gam Crv       12:15:48.1 -17:32:30  2.6  8.83  31
PPM 259621     11:54:42.6 -25:42:48  5.3  1.73  36
PPM 259481     11:48:30.5 -25:05:09  8.3  1.05  37
PPM 259543     11:51:15.0 -24:18:00  9.4  0.12  37
9857_Hecamede  11:50:58.1 -24:12:03 15.4        37
Positions are for J2000


Created by recondetail.pro, 2025/06/19 01:22:00 MT