メタデータ
| 項目 |
値 |
| Designation |
501P/Rankin |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-12-10T08:39:13.299840Z |
| Orbit solution date (soln_date, UTC) |
2025-07-31T16:54:57Z |
| Obs used |
98 |
| NEO |
Yes |
| M1 |
21.900 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-06-15T10:13:37.545600Z |
| Discovery magnitude (MPC) |
20.90 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-05-24.0000000 |
| e |
0.69572032 |
| q (au) |
0.680308 |
| a (au) |
2.235797 |
| i (deg) |
10.104448 |
| Ω (om, deg) |
140.492867 |
| ω (w, deg) |
52.799047 |
| M (ma, deg) |
156.147750 |
等級
散乱 + 全体線形
$$
M_a = (20.000 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
20.000 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.852 |
| k |
0.990 |
| δ90 |
10.000 |
| パラメータ |
記号 |
範囲 |
説明 |
| 太陽・地球距離が1 AUのときの絶対等級 |
H0 |
-5 to 20 |
彗星の固有の明るさ |
| 測光スロープパラメータ |
n |
2 to 6 |
太陽距離に対する明るさ変化率 |
| 前方散乱非対称係数 |
gf |
0.8 to 1 |
前方散乱の強さ |
| 後方散乱非対称係数 |
gb |
-1 to -0.5 |
後方散乱の強さ |
| 分配係数 |
k |
0.8 to 1 |
前方/後方散乱の寄与比 |
| ダスト/ガス明るさ比 |
δ90 |
1 to 10 |
ダスト散乱とガス放射の相対寄与 |
参考: EPSC-DPS2025-160
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2024-03-22 |
2024-07-29 |
-14.2235 |
+1.816 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
03:14:11.39 |
+08:19:46.9 |
HIP 15015 |
33.20 |
| 2026-07-29 12:00 |
03:14:31.73 |
+08:19:47.5 |
HIP 15015 |
34.97 |
| 2026-07-30 00:00 |
03:14:51.92 |
+08:19:46.8 |
HIP 15015 |
37.29 |
| 2026-07-30 12:00 |
03:15:11.96 |
+08:19:44.9 |
HIP 15099 |
39.64 |
| 2026-07-31 00:00 |
03:15:31.83 |
+08:19:41.7 |
HIP 15099 |
40.75 |
| 2026-07-31 12:00 |
03:15:51.55 |
+08:19:37.2 |
HIP 15368 |
37.71 |
| 2026-08-01 00:00 |
03:16:11.11 |
+08:19:31.3 |
HIP 15368 |
33.41 |
| 2026-08-01 12:00 |
03:16:30.50 |
+08:19:24.2 |
HIP 15368 |
29.30 |
| 2026-08-02 00:00 |
03:16:49.74 |
+08:19:15.8 |
HIP 15368 |
25.44 |
| 2026-08-02 12:00 |
03:17:08.80 |
+08:19:06.0 |
HIP 15368 |
21.96 |
| 2026-08-03 00:00 |
03:17:27.70 |
+08:18:54.9 |
HIP 15368 |
19.03 |
| 2026-08-03 12:00 |
03:17:46.43 |
+08:18:42.5 |
HIP 15368 |
16.89 |
| 2026-08-04 00:00 |
03:18:04.99 |
+08:18:28.8 |
HIP 15368 |
15.84 |
| 2026-08-04 12:00 |
03:18:23.38 |
+08:18:13.7 |
HIP 15368 |
16.05 |
| 2026-08-05 00:00 |
03:18:41.59 |
+08:17:57.3 |
HIP 15368 |
17.45 |
| 2026-08-05 12:00 |
03:18:59.63 |
+08:17:39.5 |
HIP 15368 |
19.76 |
| 2026-08-06 00:00 |
03:19:17.49 |
+08:17:20.3 |
HIP 15563 |
20.30 |
| 2026-08-06 12:00 |
03:19:35.16 |
+08:16:59.8 |
HIP 15563 |
16.83 |
| 2026-08-07 00:00 |
03:19:52.66 |
+08:16:37.9 |
HIP 15563 |
13.93 |
| 2026-08-07 12:00 |
03:20:09.97 |
+08:16:14.7 |
HIP 15563 |
11.99 |
| 2026-08-08 00:00 |
03:20:27.09 |
+08:15:50.0 |
HIP 15563 |
11.44 |
| 2026-08-08 12:00 |
03:20:44.02 |
+08:15:24.0 |
HIP 15611 |
12.38 |
| 2026-08-09 00:00 |
03:21:00.77 |
+08:14:56.6 |
HIP 15611 |
12.12 |
| 2026-08-09 12:00 |
03:21:17.32 |
+08:14:27.8 |
HIP 15611 |
13.24 |
| 2026-08-10 00:00 |
03:21:33.67 |
+08:13:57.5 |
HIP 15611 |
15.42 |
| 2026-08-10 12:00 |
03:21:49.83 |
+08:13:25.9 |
HIP 15611 |
18.24 |
| 2026-08-11 00:00 |
03:22:05.79 |
+08:12:52.8 |
HIP 15611 |
21.43 |
| 2026-08-11 12:00 |
03:22:21.55 |
+08:12:18.4 |
HIP 15611 |
24.83 |
| 2026-08-12 00:00 |
03:22:37.11 |
+08:11:42.5 |
HIP 15611 |
28.34 |
| 2026-08-12 12:00 |
03:22:52.46 |
+08:11:05.2 |
HIP 15611 |
31.90 |
| 2026-08-13 00:00 |
03:23:07.60 |
+08:10:26.4 |
HIP 15611 |
35.49 |
| 2026-08-13 12:00 |
03:23:22.53 |
+08:09:46.2 |
HIP 15960 |
34.63 |
| 2026-08-14 00:00 |
03:23:37.26 |
+08:09:04.6 |
HIP 15960 |
31.79 |
| 2026-08-14 12:00 |
03:23:51.77 |
+08:08:21.5 |
HIP 15960 |
29.20 |
| 2026-08-15 00:00 |
03:24:06.06 |
+08:07:37.0 |
HIP 15960 |
26.93 |
| 2026-08-15 12:00 |
03:24:20.14 |
+08:06:51.1 |
HIP 15960 |
25.02 |
| 2026-08-16 00:00 |
03:24:34.00 |
+08:06:03.7 |
HIP 15960 |
23.55 |
| 2026-08-16 12:00 |
03:24:47.63 |
+08:05:14.8 |
HIP 15993 |
21.28 |
| 2026-08-17 00:00 |
03:25:01.05 |
+08:04:24.5 |
HIP 15993 |
19.02 |
| 2026-08-17 12:00 |
03:25:14.24 |
+08:03:32.7 |
HIP 15993 |
17.21 |
| 2026-08-18 00:00 |
03:25:27.20 |
+08:02:39.4 |
HIP 15993 |
15.96 |
| 2026-08-18 12:00 |
03:25:39.94 |
+08:01:44.7 |
HIP 15993 |
15.40 |
| 2026-08-19 00:00 |
03:25:52.44 |
+08:00:48.5 |
HIP 15993 |
15.55 |