C/2017 E1 (Borisov)

メタデータ

項目
Designation C/2017 E1 (Borisov)
Type C
Perihelion (tp_cal, UTC) 2017-04-10T03:19:38.262720Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:33:31Z
Obs used 183
NEO -
M1 14.000
K1 32.000
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2017-03-16.0000000
e 1.00257425
q (au) 0.900663
a (au) -349.874391
i (deg) 14.554152
Ω (om, deg) 142.732826
ω (w, deg) 152.473457
M (ma, deg) -0.003786

等級

C/2017 E1 (Borisov) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (15.076 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 15.076
n 6.000
gf 1.000
gb -1.000
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
2017-03-01 2017-04-09 +33.3745 -1.729

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)
2026-07-29 00:00 06:19:13.99 +12:37:41.1 HIP 30014 5.62
2026-07-29 12:00 06:19:18.27 +12:37:32.7 HIP 30014 6.43
2026-07-30 00:00 06:19:22.54 +12:37:24.3 HIP 30014 7.29
2026-07-30 12:00 06:19:26.78 +12:37:15.7 HIP 30014 8.19
2026-07-31 00:00 06:19:31.01 +12:37:07.1 HIP 30014 9.12
2026-07-31 12:00 06:19:35.21 +12:36:58.4 HIP 30014 10.07
2026-08-01 00:00 06:19:39.39 +12:36:49.6 HIP 30014 11.03
2026-08-01 12:00 06:19:43.55 +12:36:40.7 HIP 30014 12.00
2026-08-02 00:00 06:19:47.69 +12:36:31.7 HIP 30014 12.97
2026-08-02 12:00 06:19:51.81 +12:36:22.6 HIP 30025 13.94
2026-08-03 00:00 06:19:55.90 +12:36:13.5 HIP 30025 14.84
2026-08-03 12:00 06:19:59.97 +12:36:04.2 HIP 30025 15.74
2026-08-04 00:00 06:20:04.02 +12:35:54.9 HIP 30025 16.66
2026-08-04 12:00 06:20:08.04 +12:35:45.5 HIP 30025 17.57
2026-08-05 00:00 06:20:12.05 +12:35:36.0 HIP 30025 18.50
2026-08-05 12:00 06:20:16.02 +12:35:26.5 HIP 30025 19.42
2026-08-06 00:00 06:20:19.98 +12:35:16.8 HIP 30070 20.10
2026-08-06 12:00 06:20:23.91 +12:35:07.1 HIP 30070 20.43
2026-08-07 00:00 06:20:27.81 +12:34:57.3 HIP 30070 20.79
2026-08-07 12:00 06:20:31.69 +12:34:47.4 HIP 30070 21.19
2026-08-08 00:00 06:20:35.54 +12:34:37.5 HIP 30070 21.62
2026-08-08 12:00 06:20:39.37 +12:34:27.4 HIP 30070 22.08
2026-08-09 00:00 06:20:43.18 +12:34:17.3 HIP 30070 22.57
2026-08-09 12:00 06:20:46.96 +12:34:07.1 HIP 30245 22.58
2026-08-10 00:00 06:20:50.71 +12:33:56.9 HIP 30245 22.16
2026-08-10 12:00 06:20:54.43 +12:33:46.5 HIP 30245 21.77
2026-08-11 00:00 06:20:58.13 +12:33:36.1 HIP 30245 21.42
2026-08-11 12:00 06:21:01.80 +12:33:25.6 HIP 30245 21.10
2026-08-12 00:00 06:21:05.45 +12:33:15.1 HIP 30245 20.83
2026-08-12 12:00 06:21:09.06 +12:33:04.4 HIP 30245 20.60
2026-08-13 00:00 06:21:12.65 +12:32:53.7 HIP 30245 20.41
2026-08-13 12:00 06:21:16.21 +12:32:42.9 HIP 30318 19.63
2026-08-14 00:00 06:21:19.75 +12:32:32.1 HIP 30318 18.79
2026-08-14 12:00 06:21:23.25 +12:32:21.2 HIP 30318 17.95
2026-08-15 00:00 06:21:26.73 +12:32:10.2 HIP 30318 17.13
2026-08-15 12:00 06:21:30.17 +12:31:59.2 HIP 30318 16.32
2026-08-16 00:00 06:21:33.59 +12:31:48.1 HIP 30318 15.52
2026-08-16 12:00 06:21:36.98 +12:31:36.9 HIP 30318 14.74
2026-08-17 00:00 06:21:40.34 +12:31:25.6 HIP 30318 13.97
2026-08-17 12:00 06:21:43.67 +12:31:14.3 HIP 30318 13.22
2026-08-18 00:00 06:21:46.96 +12:31:03.0 HIP 30318 12.48
2026-08-18 12:00 06:21:50.23 +12:30:51.6 HIP 30318 11.76
2026-08-19 00:00 06:21:53.47 +12:30:40.1 HIP 30318 11.07