メタデータ
| 項目 |
値 |
| Designation |
C/1997 BA6 (Spacewatch) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-11-27T13:51:09.898560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:50Z |
| Obs used |
520 |
| NEO |
- |
| M1 |
4.300 |
| K1 |
10.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2000-05-01.0000000 |
| e |
0.99888457 |
| q (au) |
3.436463 |
| a (au) |
3080.849437 |
| i (deg) |
72.717049 |
| Ω (om, deg) |
317.660522 |
| ω (w, deg) |
285.939608 |
| M (ma, deg) |
0.000896 |
等級
散乱 + 全体線形
$$
M_a = (4.715 + 5.249\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
4.715 |
| n |
5.249 |
| gf |
1.000 |
| gb |
-0.692 |
| k |
0.800 |
| 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 |
| 1997-01-11 |
1998-11-25 |
+4.3922 |
-3.507 |
| 1998-11-25 |
1999-11-21 |
-2.6888 |
+1.565 |
| 1999-11-30 |
2002-09-12 |
-3.6083 |
+2.137 |
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) |
| 2026-06-01 00:00 |
21:25:33.70 |
+59:32:10.2 |
HIP 105949 |
19.07 |
| 2026-06-01 12:00 |
21:25:32.02 |
+59:32:44.8 |
HIP 105949 |
18.84 |
| 2026-06-02 00:00 |
21:25:30.30 |
+59:33:19.2 |
HIP 105949 |
18.64 |
| 2026-06-02 12:00 |
21:25:28.55 |
+59:33:53.5 |
HIP 105949 |
18.47 |
| 2026-06-03 00:00 |
21:25:26.75 |
+59:34:27.6 |
HIP 105949 |
18.31 |
| 2026-06-03 12:00 |
21:25:24.92 |
+59:35:01.6 |
HIP 105949 |
18.18 |
| 2026-06-04 00:00 |
21:25:23.05 |
+59:35:35.5 |
HIP 105949 |
18.08 |
| 2026-06-04 12:00 |
21:25:21.15 |
+59:36:09.2 |
HIP 105949 |
18.00 |
| 2026-06-05 00:00 |
21:25:19.21 |
+59:36:42.8 |
HIP 105949 |
17.95 |
| 2026-06-05 12:00 |
21:25:17.23 |
+59:37:16.2 |
HIP 105949 |
17.92 |
| 2026-06-06 00:00 |
21:25:15.21 |
+59:37:49.5 |
HIP 105949 |
17.92 |
| 2026-06-06 12:00 |
21:25:13.16 |
+59:38:22.6 |
HIP 105621 |
17.77 |
| 2026-06-07 00:00 |
21:25:11.07 |
+59:38:55.5 |
HIP 105621 |
17.20 |
| 2026-06-07 12:00 |
21:25:08.94 |
+59:39:28.3 |
HIP 105621 |
16.62 |
| 2026-06-08 00:00 |
21:25:06.78 |
+59:40:00.9 |
HIP 105621 |
16.05 |
| 2026-06-08 12:00 |
21:25:04.58 |
+59:40:33.4 |
HIP 105621 |
15.47 |
| 2026-06-09 00:00 |
21:25:02.34 |
+59:41:05.7 |
HIP 105621 |
14.90 |
| 2026-06-09 12:00 |
21:25:00.07 |
+59:41:37.8 |
HIP 105621 |
14.33 |
| 2026-06-10 00:00 |
21:24:57.76 |
+59:42:09.8 |
HIP 105621 |
13.76 |
| 2026-06-10 12:00 |
21:24:55.42 |
+59:42:41.6 |
HIP 105621 |
13.19 |
| 2026-06-11 00:00 |
21:24:53.04 |
+59:43:13.2 |
HIP 105621 |
12.63 |
| 2026-06-11 12:00 |
21:24:50.62 |
+59:43:44.6 |
HIP 105621 |
12.06 |
| 2026-06-12 00:00 |
21:24:48.17 |
+59:44:15.8 |
HIP 105621 |
11.50 |
| 2026-06-12 12:00 |
21:24:45.69 |
+59:44:46.9 |
HIP 105621 |
10.95 |
| 2026-06-13 00:00 |
21:24:43.17 |
+59:45:17.8 |
HIP 105621 |
10.39 |
| 2026-06-13 12:00 |
21:24:40.61 |
+59:45:48.4 |
HIP 105621 |
9.84 |
| 2026-06-14 00:00 |
21:24:38.02 |
+59:46:18.9 |
HIP 105621 |
9.30 |
| 2026-06-14 12:00 |
21:24:35.39 |
+59:46:49.2 |
HIP 105621 |
8.76 |
| 2026-06-15 00:00 |
21:24:32.73 |
+59:47:19.3 |
HIP 105621 |
8.22 |
| 2026-06-15 12:00 |
21:24:30.04 |
+59:47:49.3 |
HIP 105621 |
7.70 |
| 2026-06-16 00:00 |
21:24:27.31 |
+59:48:19.0 |
HIP 105621 |
7.18 |
| 2026-06-16 12:00 |
21:24:24.54 |
+59:48:48.5 |
HIP 105621 |
6.68 |
| 2026-06-17 00:00 |
21:24:21.75 |
+59:49:17.8 |
HIP 105621 |
6.19 |
| 2026-06-17 12:00 |
21:24:18.91 |
+59:49:46.9 |
HIP 105621 |
5.72 |
| 2026-06-18 00:00 |
21:24:16.05 |
+59:50:15.7 |
HIP 105621 |
5.28 |
| 2026-06-18 12:00 |
21:24:13.15 |
+59:50:44.4 |
HIP 105621 |
4.86 |
| 2026-06-19 00:00 |
21:24:10.22 |
+59:51:12.9 |
HIP 105621 |
4.48 |
| 2026-06-19 12:00 |
21:24:07.26 |
+59:51:41.1 |
HIP 105621 |
4.15 |
| 2026-06-20 00:00 |
21:24:04.27 |
+59:52:09.2 |
HIP 105621 |
3.88 |
| 2026-06-20 12:00 |
21:24:01.24 |
+59:52:37.0 |
HIP 105621 |
3.68 |
| 2026-06-21 00:00 |
21:23:58.18 |
+59:53:04.6 |
HIP 105621 |
3.57 |
| 2026-06-21 12:00 |
21:23:55.09 |
+59:53:31.9 |
HIP 105621 |
3.55 |
| 2026-06-22 00:00 |
21:23:51.97 |
+59:53:59.1 |
HIP 105621 |
3.63 |