メタデータ
| 項目 |
値 |
| Designation |
C/1940 R2 (Cunningham) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1941-01-16T05:36:57.600000Z |
| Orbit solution date (soln_date, UTC) |
- |
| Obs used |
189 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1941-01-06.0000000 |
| e |
1.00048500 |
| q (au) |
0.367751 |
| a (au) |
-758.249484 |
| i (deg) |
49.894200 |
| Ω (om, deg) |
296.590500 |
| ω (w, deg) |
199.569000 |
| M (ma, deg) |
-0.000483 |
等級
散乱 + 全体線形
$$
M_a = (5.846 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.846 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
1.000 |
| 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) |
| 2026-09-20 00:00 |
20:17:57.86 |
-09:40:37.0 |
HIP 100138 |
17.59 |
| 2026-09-20 12:00 |
20:17:57.27 |
-09:40:41.2 |
HIP 100138 |
17.64 |
| 2026-09-21 00:00 |
20:17:56.69 |
-09:40:45.4 |
HIP 100138 |
17.69 |
| 2026-09-21 12:00 |
20:17:56.11 |
-09:40:49.6 |
HIP 100138 |
17.75 |
| 2026-09-22 00:00 |
20:17:55.54 |
-09:40:53.7 |
HIP 100138 |
17.80 |
| 2026-09-22 12:00 |
20:17:54.98 |
-09:40:57.9 |
HIP 100138 |
17.85 |
| 2026-09-23 00:00 |
20:17:54.43 |
-09:41:02.0 |
HIP 100138 |
17.91 |
| 2026-09-23 12:00 |
20:17:53.88 |
-09:41:06.1 |
HIP 100138 |
17.96 |
| 2026-09-24 00:00 |
20:17:53.34 |
-09:41:10.2 |
HIP 100138 |
18.01 |
| 2026-09-24 12:00 |
20:17:52.81 |
-09:41:14.3 |
HIP 100138 |
18.07 |
| 2026-09-25 00:00 |
20:17:52.29 |
-09:41:18.3 |
HIP 100138 |
18.12 |
| 2026-09-25 12:00 |
20:17:51.78 |
-09:41:22.4 |
HIP 100138 |
18.17 |
| 2026-09-26 00:00 |
20:17:51.27 |
-09:41:26.4 |
HIP 100138 |
18.22 |
| 2026-09-26 12:00 |
20:17:50.77 |
-09:41:30.5 |
HIP 100138 |
18.28 |
| 2026-09-27 00:00 |
20:17:50.28 |
-09:41:34.5 |
HIP 100138 |
18.33 |
| 2026-09-27 12:00 |
20:17:49.80 |
-09:41:38.5 |
HIP 100138 |
18.38 |
| 2026-09-28 00:00 |
20:17:49.32 |
-09:41:42.4 |
HIP 100138 |
18.43 |
| 2026-09-28 12:00 |
20:17:48.86 |
-09:41:46.4 |
HIP 100138 |
18.48 |
| 2026-09-29 00:00 |
20:17:48.40 |
-09:41:50.3 |
HIP 100138 |
18.53 |
| 2026-09-29 12:00 |
20:17:47.95 |
-09:41:54.3 |
HIP 100138 |
18.58 |
| 2026-09-30 00:00 |
20:17:47.51 |
-09:41:58.2 |
HIP 100138 |
18.62 |
| 2026-09-30 12:00 |
20:17:47.07 |
-09:42:02.1 |
HIP 100138 |
18.67 |
| 2026-10-01 00:00 |
20:17:46.65 |
-09:42:05.9 |
HIP 100138 |
18.72 |
| 2026-10-01 12:00 |
20:17:46.23 |
-09:42:09.8 |
HIP 100138 |
18.76 |
| 2026-10-02 00:00 |
20:17:45.82 |
-09:42:13.6 |
HIP 100138 |
18.81 |
| 2026-10-02 12:00 |
20:17:45.42 |
-09:42:17.5 |
HIP 100138 |
18.85 |
| 2026-10-03 00:00 |
20:17:45.02 |
-09:42:21.3 |
HIP 100138 |
18.89 |
| 2026-10-03 12:00 |
20:17:44.64 |
-09:42:25.0 |
HIP 100138 |
18.94 |
| 2026-10-04 00:00 |
20:17:44.26 |
-09:42:28.8 |
HIP 100138 |
18.98 |
| 2026-10-04 12:00 |
20:17:43.90 |
-09:42:32.5 |
HIP 100138 |
19.02 |
| 2026-10-05 00:00 |
20:17:43.54 |
-09:42:36.3 |
HIP 100138 |
19.06 |
| 2026-10-05 12:00 |
20:17:43.19 |
-09:42:40.0 |
HIP 100138 |
19.09 |
| 2026-10-06 00:00 |
20:17:42.85 |
-09:42:43.6 |
HIP 100138 |
19.13 |
| 2026-10-06 12:00 |
20:17:42.51 |
-09:42:47.3 |
HIP 100138 |
19.17 |
| 2026-10-07 00:00 |
20:17:42.19 |
-09:42:50.9 |
HIP 100138 |
19.20 |
| 2026-10-07 12:00 |
20:17:41.88 |
-09:42:54.5 |
HIP 100138 |
19.24 |
| 2026-10-08 00:00 |
20:17:41.57 |
-09:42:58.1 |
HIP 100138 |
19.27 |
| 2026-10-08 12:00 |
20:17:41.27 |
-09:43:01.7 |
HIP 100138 |
19.30 |
| 2026-10-09 00:00 |
20:17:40.98 |
-09:43:05.2 |
HIP 100138 |
19.33 |
| 2026-10-09 12:00 |
20:17:40.70 |
-09:43:08.8 |
HIP 100138 |
19.36 |
| 2026-10-10 00:00 |
20:17:40.43 |
-09:43:12.3 |
HIP 100138 |
19.39 |
| 2026-10-10 12:00 |
20:17:40.17 |
-09:43:15.7 |
HIP 100138 |
19.41 |
| 2026-10-11 00:00 |
20:17:39.91 |
-09:43:19.2 |
HIP 100138 |
19.44 |