メタデータ
| 項目 |
値 |
| Designation |
C/2021 K1 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-05-04T13:50:34.362240Z |
| Orbit solution date (soln_date, UTC) |
2022-07-19T01:12:51Z |
| Obs used |
676 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
19.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-05-24T14:32:49.718400Z |
| Discovery magnitude (MPC) |
16.39 o |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2021-08-19.0000000 |
| e |
0.80399384 |
| q (au) |
2.497832 |
| a (au) |
12.743639 |
| i (deg) |
16.276067 |
| Ω (om, deg) |
140.905656 |
| ω (w, deg) |
184.303821 |
| M (ma, deg) |
2.305686 |
等級
散乱 + 全体線形
$$
M_a = (8.271 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.271 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.840 |
| k |
0.995 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2020-04-20 |
2020-08-12 |
-4.6047 |
+5.290 |
| 2021-05-14 |
2021-11-24 |
-4.0011 |
+1.844 |
| 2021-11-24 |
2022-01-31 |
-10.7283 |
+4.958 |
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 |
07:00:03.69 |
+14:07:19.3 |
HIP 33651 |
14.98 |
| 2026-06-01 12:00 |
07:00:13.18 |
+14:07:21.7 |
HIP 33651 |
16.38 |
| 2026-06-02 00:00 |
07:00:22.70 |
+14:07:23.8 |
HIP 33651 |
17.97 |
| 2026-06-02 12:00 |
07:00:32.26 |
+14:07:25.7 |
HIP 33651 |
19.72 |
| 2026-06-03 00:00 |
07:00:41.85 |
+14:07:27.4 |
HIP 33651 |
21.58 |
| 2026-06-03 12:00 |
07:00:51.47 |
+14:07:28.9 |
HIP 33651 |
23.53 |
| 2026-06-04 00:00 |
07:01:01.12 |
+14:07:30.1 |
HIP 33651 |
25.56 |
| 2026-06-04 12:00 |
07:01:10.81 |
+14:07:31.0 |
HIP 33651 |
27.64 |
| 2026-06-05 00:00 |
07:01:20.52 |
+14:07:31.8 |
HIP 33944 |
27.89 |
| 2026-06-05 12:00 |
07:01:30.27 |
+14:07:32.3 |
HIP 33944 |
26.36 |
| 2026-06-06 00:00 |
07:01:40.04 |
+14:07:32.6 |
HIP 33944 |
24.95 |
| 2026-06-06 12:00 |
07:01:49.84 |
+14:07:32.6 |
HIP 33944 |
23.68 |
| 2026-06-07 00:00 |
07:01:59.67 |
+14:07:32.4 |
HIP 33997 |
22.04 |
| 2026-06-07 12:00 |
07:02:09.53 |
+14:07:32.0 |
HIP 33997 |
20.13 |
| 2026-06-08 00:00 |
07:02:19.42 |
+14:07:31.4 |
HIP 33997 |
18.34 |
| 2026-06-08 12:00 |
07:02:29.33 |
+14:07:30.5 |
HIP 33997 |
16.69 |
| 2026-06-09 00:00 |
07:02:39.28 |
+14:07:29.4 |
HIP 33997 |
15.25 |
| 2026-06-09 12:00 |
07:02:49.24 |
+14:07:28.1 |
HIP 33997 |
14.07 |
| 2026-06-10 00:00 |
07:02:59.24 |
+14:07:26.5 |
HIP 33997 |
13.24 |
| 2026-06-10 12:00 |
07:03:09.26 |
+14:07:24.7 |
HIP 33997 |
12.81 |
| 2026-06-11 00:00 |
07:03:19.30 |
+14:07:22.6 |
HIP 33997 |
12.85 |
| 2026-06-11 12:00 |
07:03:29.37 |
+14:07:20.4 |
HIP 33997 |
13.34 |
| 2026-06-12 00:00 |
07:03:39.46 |
+14:07:17.9 |
HIP 33997 |
14.25 |
| 2026-06-12 12:00 |
07:03:49.58 |
+14:07:15.2 |
HIP 33997 |
15.50 |
| 2026-06-13 00:00 |
07:03:59.71 |
+14:07:12.2 |
HIP 34162 |
16.40 |
| 2026-06-13 12:00 |
07:04:09.87 |
+14:07:09.0 |
HIP 34162 |
14.20 |
| 2026-06-14 00:00 |
07:04:20.06 |
+14:07:05.6 |
HIP 34162 |
12.09 |
| 2026-06-14 12:00 |
07:04:30.26 |
+14:07:02.0 |
HIP 34162 |
10.15 |
| 2026-06-15 00:00 |
07:04:40.48 |
+14:06:58.1 |
HIP 34162 |
8.49 |
| 2026-06-15 12:00 |
07:04:50.73 |
+14:06:54.0 |
HIP 34162 |
7.31 |
| 2026-06-16 00:00 |
07:05:00.99 |
+14:06:49.7 |
HIP 34162 |
6.87 |
| 2026-06-16 12:00 |
07:05:11.28 |
+14:06:45.1 |
HIP 34162 |
7.31 |
| 2026-06-17 00:00 |
07:05:21.58 |
+14:06:40.4 |
HIP 34162 |
8.50 |
| 2026-06-17 12:00 |
07:05:31.90 |
+14:06:35.4 |
HIP 34162 |
10.18 |
| 2026-06-18 00:00 |
07:05:42.24 |
+14:06:30.1 |
HIP 34258 |
9.20 |
| 2026-06-18 12:00 |
07:05:52.59 |
+14:06:24.7 |
HIP 34258 |
7.87 |
| 2026-06-19 00:00 |
07:06:02.96 |
+14:06:19.0 |
HIP 34258 |
7.19 |
| 2026-06-19 12:00 |
07:06:13.35 |
+14:06:13.1 |
HIP 34258 |
7.35 |
| 2026-06-20 00:00 |
07:06:23.75 |
+14:06:07.0 |
HIP 34258 |
8.32 |
| 2026-06-20 12:00 |
07:06:34.16 |
+14:06:00.7 |
HIP 34258 |
9.85 |
| 2026-06-21 00:00 |
07:06:44.59 |
+14:05:54.1 |
HIP 34258 |
11.73 |
| 2026-06-21 12:00 |
07:06:55.04 |
+14:05:47.4 |
HIP 34258 |
13.83 |
| 2026-06-22 00:00 |
07:07:05.49 |
+14:05:40.4 |
HIP 34258 |
16.05 |