C/2012 S1 (ISON)

메타데이터

항목
Designation C/2012 S1 (ISON)
Type C
Perihelion (tp_cal, UTC) 2013-11-28T18:20:55.495680Z
Orbit solution date (soln_date, UTC) 2025-11-21T13:42:48Z
Obs used 6684
NEO -
M1 10.400
K1 4.500
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2013-05-01.0000000
e 1.00000509
q (au) 0.012467
a (au) -2446.893404
i (deg) 62.162896
Ω (om, deg) 295.686541
ω (w, deg) 345.541197
M (ma, deg) -0.001724

밝기

C/2012 S1 (ISON) · Magnitude (Full range)

C/2012 S1 (ISON) · Magnitude (Highlight period)

산란 + 전체 선형

$$ M_a = (11.695 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 11.695
n 2.000
gf 1.000
gb -0.791
k 0.951
δ90 10.000
파라미터 기호 범위 설명
태양·지구거리 1 AU에서의 절대등급 H0 -5 to 20 혜성의 고유 밝기
광도 기울기 파라미터 n 2 to 6 태양거리 변화에 따른 밝기 변화율
전방 산란 비대칭 계수 gf 0.8 to 1 전방 산란의 강도
후방 산란 비대칭 계수 gb -1 to -0.5 후방 산란의 강도
분할 계수 k 0.8 to 1 전·후방 산란 기여도 비율
먼지/가스 밝기 비 δ90 1 to 10 코마에서 먼지 산란 대비 가스 방출의 상대 기여

참고: EPSC-DPS2025-160

잔차 (구간 선형)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

시작일 (UTC) 끝 (UTC) a b
2011-09-30 2013-11-13 +0.7784 -0.530
2013-11-13 2013-11-28 +7.8926 -0.124

log10 r = log10(태양거리/AU), Δ = 지구거리(AU)

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 07:20:18.49 +36:54:47.3 HIP 35477 18.13
2026-06-01 12:00 07:20:21.97 +36:54:33.1 HIP 35477 18.39
2026-06-02 00:00 07:20:25.47 +36:54:18.9 HIP 35477 18.68
2026-06-02 12:00 07:20:29.00 +36:54:04.8 HIP 35477 19.00
2026-06-03 00:00 07:20:32.55 +36:53:50.7 HIP 35477 19.34
2026-06-03 12:00 07:20:36.11 +36:53:36.7 HIP 35710 19.07
2026-06-04 00:00 07:20:39.70 +36:53:22.8 HIP 35710 18.32
2026-06-04 12:00 07:20:43.30 +36:53:08.9 HIP 35710 17.57
2026-06-05 00:00 07:20:46.93 +36:52:55.1 HIP 35710 16.82
2026-06-05 12:00 07:20:50.58 +36:52:41.3 HIP 35710 16.06
2026-06-06 00:00 07:20:54.24 +36:52:27.6 HIP 35710 15.30
2026-06-06 12:00 07:20:57.92 +36:52:13.9 HIP 35710 14.54
2026-06-07 00:00 07:21:01.63 +36:52:00.3 HIP 35710 13.78
2026-06-07 12:00 07:21:05.35 +36:51:46.8 HIP 35710 13.02
2026-06-08 00:00 07:21:09.09 +36:51:33.3 HIP 35710 12.25
2026-06-08 12:00 07:21:12.84 +36:51:19.9 HIP 35710 11.49
2026-06-09 00:00 07:21:16.62 +36:51:06.6 HIP 35710 10.72
2026-06-09 12:00 07:21:20.41 +36:50:53.3 HIP 35710 9.96
2026-06-10 00:00 07:21:24.22 +36:50:40.1 HIP 35710 9.20
2026-06-10 12:00 07:21:28.04 +36:50:27.0 HIP 35710 8.44
2026-06-11 00:00 07:21:31.89 +36:50:13.9 HIP 35710 7.69
2026-06-11 12:00 07:21:35.75 +36:50:00.9 HIP 35710 6.95
2026-06-12 00:00 07:21:39.62 +36:49:48.0 HIP 35710 6.22
2026-06-12 12:00 07:21:43.51 +36:49:35.1 HIP 35710 5.51
2026-06-13 00:00 07:21:47.42 +36:49:22.3 HIP 35710 4.82
2026-06-13 12:00 07:21:51.34 +36:49:09.5 HIP 35710 4.19
2026-06-14 00:00 07:21:55.28 +36:48:56.9 HIP 35710 3.63
2026-06-14 12:00 07:21:59.23 +36:48:44.3 HIP 35710 3.18
2026-06-15 00:00 07:22:03.20 +36:48:31.8 HIP 35710 2.89
2026-06-15 12:00 07:22:07.18 +36:48:19.3 HIP 35710 2.83
2026-06-16 00:00 07:22:11.18 +36:48:07.0 HIP 35710 3.01
2026-06-16 12:00 07:22:15.19 +36:47:54.7 HIP 35710 3.38
2026-06-17 00:00 07:22:19.21 +36:47:42.5 HIP 35710 3.90
2026-06-17 12:00 07:22:23.25 +36:47:30.3 HIP 35710 4.52
2026-06-18 00:00 07:22:27.29 +36:47:18.3 HIP 35710 5.20
2026-06-18 12:00 07:22:31.35 +36:47:06.3 HIP 35710 5.92
2026-06-19 00:00 07:22:35.43 +36:46:54.4 HIP 35710 6.68
2026-06-19 12:00 07:22:39.51 +36:46:42.5 HIP 35710 7.45
2026-06-20 00:00 07:22:43.61 +36:46:30.8 HIP 35710 8.24
2026-06-20 12:00 07:22:47.72 +36:46:19.1 HIP 35710 9.04
2026-06-21 00:00 07:22:51.84 +36:46:07.5 HIP 35710 9.85
2026-06-21 12:00 07:22:55.96 +36:45:56.0 HIP 35710 10.67
2026-06-22 00:00 07:23:00.10 +36:45:44.6 HIP 35710 11.50