Comet Archive

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C/1999 J2 (Skiff)

メタデータ

項目
Designation C/1999 J2 (Skiff)
Type C
Perihelion (tp_cal, UTC) 2000-04-05T23:39:38.044800Z
Orbit solution date (soln_date, UTC) 2025-07-31T12:12:22Z
Obs used 978
NEO -
M1 6.100
K1 7.000
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2000-04-28.0000000
e 1.00112158
q (au) 7.109764
a (au) -6339.047335
i (deg) 86.412859
Ω (om, deg) 50.042373
ω (w, deg) 127.138683
M (ma, deg) 0.000043

等級

C/1999 J2 (Skiff) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (-2.294 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 -2.294
n 6.000
gf 1.000
gb -0.500
k 1.000
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
2000-04-06 2002-03-22 +20.3121 -17.666
2002-03-22 2003-05-29 +4.9690 -3.057

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)
2026-02-03 00:00 07:01:40.77 -77:40:44.7 HIP 34020 16.89
2026-02-03 12:00 07:01:28.63 -77:40:23.1 HIP 34020 17.46
2026-02-04 00:00 07:01:16.57 -77:40:01.2 HIP 34020 18.04
2026-02-04 12:00 07:01:04.57 -77:39:38.9 HIP 34020 18.64
2026-02-05 00:00 07:00:52.64 -77:39:16.3 HIP 34020 19.25
2026-02-05 12:00 07:00:40.78 -77:38:53.3 HIP 34020 19.87
2026-02-06 00:00 07:00:29.00 -77:38:30.0 HIP 34020 20.51
2026-02-06 12:00 07:00:17.28 -77:38:06.4 HIP 34020 21.15
2026-02-07 00:00 07:00:05.65 -77:37:42.4 HIP 33140 21.34
2026-02-07 12:00 06:59:54.08 -77:37:18.1 HIP 33140 20.97
2026-02-08 00:00 06:59:42.59 -77:36:53.5 HIP 33140 20.62
2026-02-08 12:00 06:59:31.18 -77:36:28.6 HIP 33140 20.31
2026-02-09 00:00 06:59:19.84 -77:36:03.3 HIP 33140 20.02
2026-02-09 12:00 06:59:08.59 -77:35:37.7 HIP 33140 19.76
2026-02-10 00:00 06:58:57.41 -77:35:11.8 HIP 33140 19.53
2026-02-10 12:00 06:58:46.31 -77:34:45.5 HIP 33140 19.33
2026-02-11 00:00 06:58:35.30 -77:34:19.0 HIP 33140 19.17
2026-02-11 12:00 06:58:24.36 -77:33:52.1 HIP 33140 19.03
2026-02-12 00:00 06:58:13.51 -77:33:25.0 HIP 33140 18.94
2026-02-12 12:00 06:58:02.74 -77:32:57.5 HIP 33140 18.87
2026-02-13 00:00 06:57:52.06 -77:32:29.7 HIP 33140 18.84
2026-02-13 12:00 06:57:41.46 -77:32:01.6 HIP 33140 18.85
2026-02-14 00:00 06:57:30.95 -77:31:33.2 HIP 33140 18.89
2026-02-14 12:00 06:57:20.52 -77:31:04.6 HIP 33140 18.97
2026-02-15 00:00 06:57:10.19 -77:30:35.6 HIP 33140 19.08
2026-02-15 12:00 06:56:59.94 -77:30:06.3 HIP 33140 19.22
2026-02-16 00:00 06:56:49.78 -77:29:36.8 HIP 33140 19.40
2026-02-16 12:00 06:56:39.71 -77:29:06.9 HIP 33140 19.61
2026-02-17 00:00 06:56:29.73 -77:28:36.8 HIP 33140 19.85
2026-02-17 12:00 06:56:19.84 -77:28:06.4 HIP 33140 20.12
2026-02-18 00:00 06:56:10.05 -77:27:35.7 HIP 33140 20.41
2026-02-18 12:00 06:56:00.35 -77:27:04.8 HIP 32884 20.67
2026-02-19 00:00 06:55:50.74 -77:26:33.6 HIP 32884 20.63
2026-02-19 12:00 06:55:41.23 -77:26:02.1 HIP 32884 20.62
2026-02-20 00:00 06:55:31.81 -77:25:30.3 HIP 32884 20.65
2026-02-20 12:00 06:55:22.49 -77:24:58.3 HIP 32884 20.70
2026-02-21 00:00 06:55:13.26 -77:24:26.0 HIP 32884 20.79
2026-02-21 12:00 06:55:04.13 -77:23:53.5 HIP 32884 20.91
2026-02-22 00:00 06:54:55.10 -77:23:20.7 HIP 32884 21.06
2026-02-22 12:00 06:54:46.16 -77:22:47.7 HIP 32884 21.24
2026-02-23 00:00 06:54:37.33 -77:22:14.4 HIP 32884 21.46
2026-02-23 12:00 06:54:28.59 -77:21:40.9 HIP 32884 21.69
2026-02-24 00:00 06:54:19.95 -77:21:07.1 HIP 32884 21.96