C/2020 S3 (Erasmus)

メタデータ

項目
Designation C/2020 S3 (Erasmus)
Type C
Perihelion (tp_cal, UTC) 2020-12-12T16:07:52.118400Z
Orbit solution date (soln_date, UTC) 2024-04-29T13:12:18Z
Obs used 861
NEO -
M1 13.000
K1 4.500
PC 0.030
Discovery observation (MPC, UTC) 2020-09-17T14:40:43.536000Z
Discovery magnitude (MPC) 18.48 o
Discovery observatory (MPC) T08 · ATLAS-MLO, Mauna Loa
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2021-03-11.0000000
e 0.99795482
q (au) 0.398469
a (au) 194.833484
i (deg) 19.861463
Ω (om, deg) 222.992545
ω (w, deg) 349.885700
M (ma, deg) 0.032012

等級

C/2020 S3 (Erasmus) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (10.351 + 5.209\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 10.351
n 5.209
gf 1.000
gb -0.884
k 0.958
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
2020-09-17 2020-10-17 +19.9753 -1.996
2020-10-17 2020-11-05 -0.9153 -0.033
2020-11-05 2020-12-09 -2.1755 -0.819
2020-12-18 2020-12-28 +3.4304 +1.116
2020-12-28 2021-07-09 -1.2828 -0.363
2021-07-09 2021-09-12 +18.1671 -11.093
2021-09-12 2021-11-27 -10.8203 +6.847

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 00:59:00.70 +15:39:54.8 HIP 4666 14.14
2026-06-01 12:00 00:59:04.74 +15:40:30.3 HIP 4666 13.03
2026-06-02 00:00 00:59:08.73 +15:41:05.7 HIP 4666 11.95
2026-06-02 12:00 00:59:12.68 +15:41:40.9 HIP 4666 10.88
2026-06-03 00:00 00:59:16.59 +15:42:15.9 HIP 4666 9.84
2026-06-03 12:00 00:59:20.46 +15:42:50.8 HIP 4666 8.82
2026-06-04 00:00 00:59:24.28 +15:43:25.4 HIP 4666 7.83
2026-06-04 12:00 00:59:28.06 +15:44:00.0 HIP 4666 6.88
2026-06-05 00:00 00:59:31.80 +15:44:34.2 HIP 4666 5.99
2026-06-05 12:00 00:59:35.49 +15:45:08.3 HIP 4666 5.17
2026-06-06 00:00 00:59:39.14 +15:45:42.2 HIP 4666 4.46
2026-06-06 12:00 00:59:42.74 +15:46:16.0 HIP 4666 3.92
2026-06-07 00:00 00:59:46.30 +15:46:49.5 HIP 4666 3.60
2026-06-07 12:00 00:59:49.82 +15:47:22.9 HIP 4666 3.56
2026-06-08 00:00 00:59:53.29 +15:47:56.0 HIP 4666 3.79
2026-06-08 12:00 00:59:56.71 +15:48:29.0 HIP 4666 4.25
2026-06-09 00:00 01:00:00.09 +15:49:01.7 HIP 4666 4.87
2026-06-09 12:00 01:00:03.42 +15:49:34.3 HIP 4666 5.59
2026-06-10 00:00 01:00:06.71 +15:50:06.6 HIP 4666 6.36
2026-06-10 12:00 01:00:09.95 +15:50:38.7 HIP 4666 7.17
2026-06-11 00:00 01:00:13.14 +15:51:10.7 HIP 4666 8.00
2026-06-11 12:00 01:00:16.29 +15:51:42.4 HIP 4666 8.85
2026-06-12 00:00 01:00:19.39 +15:52:13.9 HIP 4666 9.69
2026-06-12 12:00 01:00:22.45 +15:52:45.1 HIP 4666 10.54
2026-06-13 00:00 01:00:25.45 +15:53:16.2 HIP 4666 11.39
2026-06-13 12:00 01:00:28.41 +15:53:47.0 HIP 4666 12.23
2026-06-14 00:00 01:00:31.32 +15:54:17.6 HIP 4666 13.07
2026-06-14 12:00 01:00:34.18 +15:54:48.0 HIP 4666 13.90
2026-06-15 00:00 01:00:36.99 +15:55:18.2 HIP 4666 14.72
2026-06-15 12:00 01:00:39.75 +15:55:48.1 HIP 4666 15.54
2026-06-16 00:00 01:00:42.47 +15:56:17.8 HIP 4666 16.34
2026-06-16 12:00 01:00:45.13 +15:56:47.3 HIP 4666 17.14
2026-06-17 00:00 01:00:47.75 +15:57:16.5 HIP 4666 17.92
2026-06-17 12:00 01:00:50.31 +15:57:45.5 HIP 4666 18.70
2026-06-18 00:00 01:00:52.83 +15:58:14.2 HIP 4666 19.46
2026-06-18 12:00 01:00:55.29 +15:58:42.7 HIP 4666 20.22
2026-06-19 00:00 01:00:57.71 +15:59:10.9 HIP 4666 20.96
2026-06-19 12:00 01:01:00.08 +15:59:39.0 HIP 4666 21.69
2026-06-20 00:00 01:01:02.39 +16:00:06.7 HIP 4754 22.29
2026-06-20 12:00 01:01:04.65 +16:00:34.2 HIP 4754 21.81
2026-06-21 00:00 01:01:06.87 +16:01:01.5 HIP 4754 21.36
2026-06-21 12:00 01:01:09.03 +16:01:28.5 HIP 4754 20.92
2026-06-22 00:00 01:01:11.14 +16:01:55.2 HIP 4754 20.49