メタデータ
| 項目 |
値 |
| Designation |
C/2021 E3 (ZTF) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-06-11T21:41:58.525440Z |
| Orbit solution date (soln_date, UTC) |
2026-03-11T21:13:02Z |
| Obs used |
1491 |
| NEO |
- |
| M1 |
11.100 |
| K1 |
5.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-03-09T12:41:11.904000Z |
| Discovery magnitude (MPC) |
19.60 r |
| Discovery observatory (MPC) |
I41 · Palomar Mountain–ZTF |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-02-28.0000000 |
| e |
1.00086348 |
| q (au) |
1.777410 |
| a (au) |
-2058.429778 |
| i (deg) |
112.555637 |
| Ω (om, deg) |
104.468418 |
| ω (w, deg) |
228.845737 |
| M (ma, deg) |
-0.001097 |
等級
散乱 + 全体線形
$$
M_a = (10.650 + 3.246\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.650 |
| n |
3.246 |
| gf |
1.000 |
| gb |
-0.558 |
| 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 |
| 2021-03-09 |
2022-06-10 |
+4.2489 |
-2.716 |
| 2022-06-16 |
2022-11-11 |
+10.7149 |
-4.279 |
| 2022-11-11 |
2024-01-13 |
-0.3955 |
+0.570 |
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) |
| 2026-03-26 00:00 |
06:37:10.18 |
+26:42:43.7 |
HIP 31545 |
14.13 |
| 2026-03-26 12:00 |
06:37:09.14 |
+26:42:56.6 |
HIP 31545 |
14.00 |
| 2026-03-27 00:00 |
06:37:08.21 |
+26:43:09.4 |
HIP 31535 |
13.88 |
| 2026-03-27 12:00 |
06:37:07.37 |
+26:43:22.0 |
HIP 31535 |
13.70 |
| 2026-03-28 00:00 |
06:37:06.62 |
+26:43:34.6 |
HIP 31535 |
13.54 |
| 2026-03-28 12:00 |
06:37:05.98 |
+26:43:47.0 |
HIP 31535 |
13.41 |
| 2026-03-29 00:00 |
06:37:05.42 |
+26:43:59.4 |
HIP 31535 |
13.30 |
| 2026-03-29 12:00 |
06:37:04.96 |
+26:44:11.6 |
HIP 31535 |
13.22 |
| 2026-03-30 00:00 |
06:37:04.60 |
+26:44:23.7 |
HIP 31535 |
13.16 |
| 2026-03-30 12:00 |
06:37:04.33 |
+26:44:35.7 |
HIP 31535 |
13.12 |
| 2026-03-31 00:00 |
06:37:04.15 |
+26:44:47.7 |
HIP 31535 |
13.11 |
| 2026-03-31 12:00 |
06:37:04.07 |
+26:44:59.5 |
HIP 31535 |
13.12 |
| 2026-04-01 00:00 |
06:37:04.08 |
+26:45:11.2 |
HIP 31535 |
13.16 |
| 2026-04-01 12:00 |
06:37:04.18 |
+26:45:22.8 |
HIP 31535 |
13.22 |
| 2026-04-02 00:00 |
06:37:04.38 |
+26:45:34.3 |
HIP 31535 |
13.30 |
| 2026-04-02 12:00 |
06:37:04.67 |
+26:45:45.8 |
HIP 31535 |
13.40 |
| 2026-04-03 00:00 |
06:37:05.05 |
+26:45:57.1 |
HIP 31535 |
13.52 |
| 2026-04-03 12:00 |
06:37:05.52 |
+26:46:08.3 |
HIP 31535 |
13.67 |
| 2026-04-04 00:00 |
06:37:06.08 |
+26:46:19.5 |
HIP 31535 |
13.83 |
| 2026-04-04 12:00 |
06:37:06.73 |
+26:46:30.5 |
HIP 31535 |
14.02 |
| 2026-04-05 00:00 |
06:37:07.47 |
+26:46:41.5 |
HIP 31535 |
14.23 |
| 2026-04-05 12:00 |
06:37:08.31 |
+26:46:52.3 |
HIP 31535 |
14.46 |
| 2026-04-06 00:00 |
06:37:09.23 |
+26:47:03.1 |
HIP 31535 |
14.71 |
| 2026-04-06 12:00 |
06:37:10.24 |
+26:47:13.8 |
HIP 31535 |
14.97 |
| 2026-04-07 00:00 |
06:37:11.35 |
+26:47:24.4 |
HIP 31535 |
15.26 |
| 2026-04-07 12:00 |
06:37:12.54 |
+26:47:34.9 |
HIP 31535 |
15.57 |
| 2026-04-08 00:00 |
06:37:13.82 |
+26:47:45.3 |
HIP 31535 |
15.89 |
| 2026-04-08 12:00 |
06:37:15.18 |
+26:47:55.7 |
HIP 31535 |
16.23 |
| 2026-04-09 00:00 |
06:37:16.64 |
+26:48:05.9 |
HIP 31535 |
16.60 |
| 2026-04-09 12:00 |
06:37:18.18 |
+26:48:16.1 |
HIP 31535 |
16.98 |
| 2026-04-10 00:00 |
06:37:19.81 |
+26:48:26.2 |
HIP 31535 |
17.38 |
| 2026-04-10 12:00 |
06:37:21.53 |
+26:48:36.2 |
HIP 31759 |
17.47 |
| 2026-04-11 00:00 |
06:37:23.33 |
+26:48:46.1 |
HIP 31759 |
17.03 |
| 2026-04-11 12:00 |
06:37:25.22 |
+26:48:56.0 |
HIP 31759 |
16.58 |
| 2026-04-12 00:00 |
06:37:27.20 |
+26:49:05.7 |
HIP 31759 |
16.11 |
| 2026-04-12 12:00 |
06:37:29.26 |
+26:49:15.4 |
HIP 31759 |
15.62 |
| 2026-04-13 00:00 |
06:37:31.40 |
+26:49:25.0 |
HIP 31759 |
15.12 |
| 2026-04-13 12:00 |
06:37:33.63 |
+26:49:34.5 |
HIP 31759 |
14.60 |
| 2026-04-14 00:00 |
06:37:35.94 |
+26:49:44.0 |
HIP 31759 |
14.06 |
| 2026-04-14 12:00 |
06:37:38.34 |
+26:49:53.3 |
HIP 31759 |
13.50 |
| 2026-04-15 00:00 |
06:37:40.82 |
+26:50:02.6 |
HIP 31759 |
12.93 |
| 2026-04-15 12:00 |
06:37:43.38 |
+26:50:11.9 |
HIP 31759 |
12.34 |
| 2026-04-16 00:00 |
06:37:46.03 |
+26:50:21.0 |
HIP 31759 |
11.73 |