メタデータ
| 項目 |
値 |
| Designation |
C/2021 X2 (Bok) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-07-08T03:45:12.778560Z |
| Orbit solution date (soln_date, UTC) |
2024-04-15T15:43:28Z |
| Obs used |
95 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
16.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-12-01T09:04:17.558400Z |
| Discovery magnitude (MPC) |
21.60 G |
| Discovery observatory (MPC) |
V00 · Kitt Peak-Bok |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-06-25.0000000 |
| e |
1.00130749 |
| q (au) |
2.994542 |
| a (au) |
-2290.292591 |
| i (deg) |
137.143974 |
| Ω (om, deg) |
228.798155 |
| ω (w, deg) |
193.283930 |
| M (ma, deg) |
-0.000118 |
等級
散乱 + 全体線形
$$
M_a = (10.258 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.258 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
17:17:43.35 |
-54:42:15.5 |
HIP 84755 |
25.54 |
| 2026-07-29 12:00 |
17:17:28.60 |
-54:40:49.3 |
HIP 84755 |
25.81 |
| 2026-07-30 00:00 |
17:17:14.00 |
-54:39:22.7 |
HIP 84755 |
26.30 |
| 2026-07-30 12:00 |
17:16:59.54 |
-54:37:55.7 |
HIP 84339 |
26.41 |
| 2026-07-31 00:00 |
17:16:45.23 |
-54:36:28.3 |
HIP 84339 |
23.88 |
| 2026-07-31 12:00 |
17:16:31.07 |
-54:35:00.5 |
HIP 84339 |
21.36 |
| 2026-08-01 00:00 |
17:16:17.05 |
-54:33:32.4 |
HIP 84339 |
18.86 |
| 2026-08-01 12:00 |
17:16:03.18 |
-54:32:03.9 |
HIP 84339 |
16.36 |
| 2026-08-02 00:00 |
17:15:49.46 |
-54:30:35.0 |
HIP 84339 |
13.88 |
| 2026-08-02 12:00 |
17:15:35.89 |
-54:29:05.8 |
HIP 84339 |
11.41 |
| 2026-08-03 00:00 |
17:15:22.47 |
-54:27:36.3 |
HIP 84339 |
8.96 |
| 2026-08-03 12:00 |
17:15:09.20 |
-54:26:06.5 |
HIP 84339 |
6.52 |
| 2026-08-04 00:00 |
17:14:56.07 |
-54:24:36.3 |
HIP 84339 |
4.09 |
| 2026-08-04 12:00 |
17:14:43.10 |
-54:23:05.8 |
HIP 84339 |
1.68 |
| 2026-08-05 00:00 |
17:14:30.28 |
-54:21:35.1 |
HIP 84339 |
0.77 |
| 2026-08-05 12:00 |
17:14:17.61 |
-54:20:04.0 |
HIP 84339 |
3.14 |
| 2026-08-06 00:00 |
17:14:05.09 |
-54:18:32.7 |
HIP 84339 |
5.51 |
| 2026-08-06 12:00 |
17:13:52.72 |
-54:17:01.1 |
HIP 84339 |
7.87 |
| 2026-08-07 00:00 |
17:13:40.51 |
-54:15:29.3 |
HIP 84339 |
10.22 |
| 2026-08-07 12:00 |
17:13:28.45 |
-54:13:57.2 |
HIP 84339 |
12.56 |
| 2026-08-08 00:00 |
17:13:16.54 |
-54:12:24.8 |
HIP 84339 |
14.88 |
| 2026-08-08 12:00 |
17:13:04.79 |
-54:10:52.3 |
HIP 84339 |
17.19 |
| 2026-08-09 00:00 |
17:12:53.19 |
-54:09:19.5 |
HIP 84339 |
19.49 |
| 2026-08-09 12:00 |
17:12:41.75 |
-54:07:46.4 |
HIP 84339 |
21.77 |
| 2026-08-10 00:00 |
17:12:30.46 |
-54:06:13.2 |
HIP 84339 |
24.04 |
| 2026-08-10 12:00 |
17:12:19.32 |
-54:04:39.8 |
HIP 84339 |
26.29 |
| 2026-08-11 00:00 |
17:12:08.35 |
-54:03:06.2 |
HIP 83960 |
27.11 |
| 2026-08-11 12:00 |
17:11:57.52 |
-54:01:32.4 |
HIP 83960 |
26.96 |
| 2026-08-12 00:00 |
17:11:46.86 |
-53:59:58.5 |
HIP 83960 |
27.00 |
| 2026-08-12 12:00 |
17:11:36.35 |
-53:58:24.3 |
HIP 83960 |
27.23 |
| 2026-08-13 00:00 |
17:11:25.99 |
-53:56:50.1 |
HIP 83960 |
27.66 |
| 2026-08-13 12:00 |
17:11:15.79 |
-53:55:15.7 |
HIP 83960 |
28.25 |
| 2026-08-14 00:00 |
17:11:05.75 |
-53:53:41.1 |
HIP 83960 |
29.01 |
| 2026-08-14 12:00 |
17:10:55.87 |
-53:52:06.5 |
HIP 83960 |
29.92 |
| 2026-08-15 00:00 |
17:10:46.14 |
-53:50:31.7 |
HIP 83934 |
29.74 |
| 2026-08-15 12:00 |
17:10:36.57 |
-53:48:56.8 |
HIP 83934 |
27.72 |
| 2026-08-16 00:00 |
17:10:27.16 |
-53:47:21.8 |
HIP 83934 |
25.72 |
| 2026-08-16 12:00 |
17:10:17.90 |
-53:45:46.7 |
HIP 83934 |
23.75 |
| 2026-08-17 00:00 |
17:10:08.80 |
-53:44:11.6 |
HIP 83934 |
21.81 |
| 2026-08-17 12:00 |
17:09:59.86 |
-53:42:36.4 |
HIP 83934 |
19.90 |
| 2026-08-18 00:00 |
17:09:51.07 |
-53:41:01.1 |
HIP 83934 |
18.03 |
| 2026-08-18 12:00 |
17:09:42.44 |
-53:39:25.7 |
HIP 83934 |
16.21 |
| 2026-08-19 00:00 |
17:09:33.96 |
-53:37:50.4 |
HIP 83934 |
14.45 |