488474 (1999 HD1)

NEO ⇩ IMP ⇩ COV ★ EPH ⇩ OBS
Orbital Elements
Epoch (TDB)2025-11-21 (JD 2461000.5)
Eccentricity (e)0.4179191902 ± 1.47e-07
Semi-major axis (a)1.1318781918 AU ± 4.25e-09
Inclination (i)18.21466714° ± 1.45e-05
Long. of Asc. Node (Ω)209.85119632° ± 1.31e-05
Arg. of Perihelion (ω)147.97798299° ± 2.28e-05
Mean Anomaly (M)285.35280547° ± 3.03e-05
Mean Motion (n)0.8184887937°/day ± 4.61e-09
Perihelion dist (q)0.65884457 AU ± 1.66e-07
Aphelion dist (Q)1.60491181 AU ± 1.66e-07
Orbital Period1.20420254 yr ± 6.78e-09
Physical Parameters
H (abs. magnitude)20.32
G (slope)0.15
Orbit Solution
SourceIAA
Solution Date2026-05-31
RMS Residual0.386″
Uncertainty0
Orbit TypeApollo
MOID0.216594 AU
Observations Used102
Oppositions4
Arc Total1999-2024
First Observation Used1999-04-16
Last Observation Used2024-03-17
Observations (105)
Date Type RA Dec Mag Band Observatory
1999-04-16 09:53:52 C 14 40 40.31 -14 30 15.6 i 691
1999-04-16 10:25:07 C 14 40 37.77 -14 29 25.2 i 691
1999-04-16 10:56:27 C 14 40 35.25 -14 28 34.8 i 691
1999-04-17 06:11:03 C 14 39 07.19 -13 57 06.6 i 691
1999-04-17 06:22:38 C 14 39 06.15 -13 56 47.0 i 691
1999-04-17 07:15:17 C 14 39 01.76 -13 55 19.9 i 691
1999-04-17 10:12:28 C 14 38 46.85 -13 50 25.1 i 691
1999-04-17 10:18:35 C 14 38 46.36 -13 50 14.9 i 691
1999-04-17 10:27:04 C 14 38 45.67 -13 50 00.3 i 691
1999-04-17 10:35:30 C 14 38 44.92 -13 49 46.2 i 691
1999-04-17 10:43:16 C 14 38 44.28 -13 49 33.3 i 691
1999-04-18 00:00:52 C 14 37 41.01 -13 27 14.2 557
1999-04-18 00:07:36 C 14 37 40.37 -13 27 01.0 557
1999-04-18 00:11:06 C 14 37 40.10 -13 26 57.3 557
1999-04-18 00:14:49 C 14 37 39.76 -13 26 50.1 557
1999-04-18 13:31:05 C 14 36 35.17 -13 03 40.0 422
1999-04-18 13:34:14 C 14 36 34.98 -13 03 32.8 422
1999-04-18 13:42:34 C 14 36 34.07 -13 03 18.2 422
1999-04-19 06:54:06 C 14 35 07.74 -12 33 34.7 i 691
1999-04-19 06:59:32 C 14 35 07.32 -12 33 25.5 i 691
1999-04-19 07:06:43 C 14 35 06.67 -12 33 13.5 i 691
1999-04-21 00:28:47 C 14 31 29.69 -11 17 59.7 d 046
1999-04-21 00:31:13 C 14 31 29.43 -11 17 55.4 d 046
1999-04-21 00:33:47 C 14 31 29.11 -11 17 50.1 d 046
1999-04-21 00:35:49 C 14 31 28.94 -11 17 45.5 d 046
1999-04-21 00:38:23 C 14 31 28.76 -11 17 40.7 d 046
1999-04-21 00:41:11 C 14 31 28.42 -11 17 35.0 d 046
1999-05-16 11:44:37 C 13 25 52.67 +11 20 36.9 426
1999-05-16 11:53:39 C 13 25 51.71 +11 20 55.9 426
1999-05-16 12:02:43 C 13 25 50.68 +11 21 15.4 426
1999-05-17 05:18:48 C 13 24 02.25 +11 57 30.3 i 691
1999-05-17 05:26:46 C 13 24 01.36 +11 57 46.9 i 691
1999-05-17 05:35:12 C 13 24 00.46 +11 58 04.3 i 691
2005-04-13 07:44:49 C 14 08 55.88 -15 54 07.6 c 691
2005-04-13 08:09:33 C 14 08 53.59 -15 53 30.3 c 691
2005-04-13 08:34:30 C 14 08 51.38 -15 52 53.3 c 691
2005-04-17 08:17:02 C 14 00 07.90 -13 19 21.7 c 691
2005-04-17 08:44:09 C 14 00 05.18 -13 18 35.2 c 691
2005-04-17 09:10:43 C 14 00 02.52 -13 17 50.0 c 691
2005-05-07 04:07:41 C 13 11 15.69 +02 08 15.5 c 691
2005-05-07 04:31:16 C 13 11 13.26 +02 09 02.0 c 691
2005-05-07 04:54:14 C 13 11 10.89 +02 09 47.4 c 691
2005-06-01 05:46:57 C 12 30 48.946 +17 31 17.07 n 645
2005-06-01 05:46:57 C 12 30 48.95 +17 31 17.1 n 645
2005-06-01 05:48:09 C 12 30 48.898 +17 31 18.38 n 645
2005-06-01 05:48:09 C 12 30 48.90 +17 31 18.4 n 645
2005-06-01 05:50:32 C 12 30 48.81 +17 31 20.7 n 645
2005-06-01 05:51:44 C 12 30 48.760 +17 31 21.98 n 645
2005-06-01 05:51:44 C 12 30 48.76 +17 31 21.9 n 645
2005-06-04 05:43:17 C 12 28 39.612 +18 43 56.75 e 645