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) |
| 2026-05-12 00:00 |
21:26:09.20 |
+59:07:43.1 |
HIP 105883 |
4.40 |
| 2026-05-12 12:00 |
21:26:09.08 |
+59:08:21.1 |
HIP 105883 |
4.66 |
| 2026-05-13 00:00 |
21:26:08.92 |
+59:08:59.1 |
HIP 105883 |
5.00 |
| 2026-05-13 12:00 |
21:26:08.72 |
+59:09:37.1 |
HIP 105883 |
5.39 |
| 2026-05-14 00:00 |
21:26:08.48 |
+59:10:15.0 |
HIP 105883 |
5.83 |
| 2026-05-14 12:00 |
21:26:08.20 |
+59:10:52.9 |
HIP 105883 |
6.30 |
| 2026-05-15 00:00 |
21:26:07.89 |
+59:11:30.8 |
HIP 105883 |
6.81 |
| 2026-05-15 12:00 |
21:26:07.53 |
+59:12:08.5 |
HIP 105883 |
7.33 |
| 2026-05-16 00:00 |
21:26:07.13 |
+59:12:46.3 |
HIP 105883 |
7.87 |
| 2026-05-16 12:00 |
21:26:06.70 |
+59:13:24.0 |
HIP 105883 |
8.43 |
| 2026-05-17 00:00 |
21:26:06.22 |
+59:14:01.6 |
HIP 105883 |
9.00 |
| 2026-05-17 12:00 |
21:26:05.70 |
+59:14:39.1 |
HIP 105883 |
9.58 |
| 2026-05-18 00:00 |
21:26:05.15 |
+59:15:16.6 |
HIP 105883 |
10.16 |
| 2026-05-18 12:00 |
21:26:04.55 |
+59:15:54.1 |
HIP 105883 |
10.76 |
| 2026-05-19 00:00 |
21:26:03.92 |
+59:16:31.4 |
HIP 105883 |
11.35 |
| 2026-05-19 12:00 |
21:26:03.24 |
+59:17:08.7 |
HIP 105960 |
11.42 |
| 2026-05-20 00:00 |
21:26:02.53 |
+59:17:45.9 |
HIP 105960 |
11.50 |
| 2026-05-20 12:00 |
21:26:01.78 |
+59:18:23.1 |
HIP 105960 |
11.61 |
| 2026-05-21 00:00 |
21:26:00.98 |
+59:19:00.1 |
HIP 105960 |
11.77 |
| 2026-05-21 12:00 |
21:26:00.15 |
+59:19:37.1 |
HIP 105960 |
11.96 |
| 2026-05-22 00:00 |
21:25:59.28 |
+59:20:14.0 |
HIP 105960 |
12.18 |
| 2026-05-22 12:00 |
21:25:58.37 |
+59:20:50.8 |
HIP 105960 |
12.43 |
| 2026-05-23 00:00 |
21:25:57.42 |
+59:21:27.5 |
HIP 105960 |
12.71 |
| 2026-05-23 12:00 |
21:25:56.43 |
+59:22:04.1 |
HIP 105960 |
13.03 |
| 2026-05-24 00:00 |
21:25:55.40 |
+59:22:40.6 |
HIP 105960 |
13.36 |
| 2026-05-24 12:00 |
21:25:54.34 |
+59:23:17.1 |
HIP 105960 |
13.72 |
| 2026-05-25 00:00 |
21:25:53.23 |
+59:23:53.4 |
HIP 105960 |
14.11 |
| 2026-05-25 12:00 |
21:25:52.08 |
+59:24:29.6 |
HIP 105960 |
14.51 |
| 2026-05-26 00:00 |
21:25:50.90 |
+59:25:05.7 |
HIP 105960 |
14.93 |
| 2026-05-26 12:00 |
21:25:49.68 |
+59:25:41.7 |
HIP 105960 |
15.37 |
| 2026-05-27 00:00 |
21:25:48.42 |
+59:26:17.6 |
HIP 105960 |
15.82 |
| 2026-05-27 12:00 |
21:25:47.12 |
+59:26:53.4 |
HIP 105960 |
16.29 |
| 2026-05-28 00:00 |
21:25:45.78 |
+59:27:29.1 |
HIP 105960 |
16.77 |
| 2026-05-28 12:00 |
21:25:44.40 |
+59:28:04.7 |
HIP 105960 |
17.26 |
| 2026-05-29 00:00 |
21:25:42.99 |
+59:28:40.1 |
HIP 105960 |
17.76 |
| 2026-05-29 12:00 |
21:25:41.54 |
+59:29:15.5 |
HIP 105960 |
18.27 |
| 2026-05-30 00:00 |
21:25:40.05 |
+59:29:50.7 |
HIP 105960 |
18.79 |
| 2026-05-30 12:00 |
21:25:38.52 |
+59:30:25.7 |
HIP 105960 |
19.32 |
| 2026-05-31 00:00 |
21:25:36.95 |
+59:31:00.7 |
HIP 105949 |
19.58 |
| 2026-05-31 12:00 |
21:25:35.34 |
+59:31:35.5 |
HIP 105949 |
19.31 |
| 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 |