C/2008 A1 (McNaught)

메타데이터

항목
Designation C/2008 A1 (McNaught)
Type C
Perihelion (tp_cal, UTC) 2008-09-29T02:59:09.844800Z
Orbit solution date (soln_date, UTC) 2021-04-16T12:07:02Z
Obs used 906
NEO -
M1 8.100
K1 10.000
PC 0.030
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2008-09-26.0000000
e 1.00023047
q (au) 1.073075
a (au) -4655.992023
i (deg) 82.549175
Ω (om, deg) 277.883699
ω (w, deg) 348.473258
M (ma, deg) -0.000010

밝기

C/2008 A1 (McNaught) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (10.584 + 3.102\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 10.584
n 3.102
gf 0.998
gb -0.500
k 0.800
δ90 8.390
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
2008-01-10 2008-09-28 +4.7194 -3.531
2008-09-29 2008-11-02 +10.5269 -3.006
2008-11-02 2010-01-17 +3.3602 -1.676

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 06:15:53.88 +53:32:32.0 HIP 29795 5.57
2026-06-01 12:00 06:15:58.66 +53:32:19.9 HIP 29795 4.90
2026-06-02 00:00 06:16:03.45 +53:32:08.0 HIP 29795 4.24
2026-06-02 12:00 06:16:08.26 +53:31:56.3 HIP 29795 3.62
2026-06-03 00:00 06:16:13.08 +53:31:44.8 HIP 29795 3.06
2026-06-03 12:00 06:16:17.92 +53:31:33.4 HIP 29795 2.58
2026-06-04 00:00 06:16:22.77 +53:31:22.2 HIP 29795 2.26
2026-06-04 12:00 06:16:27.63 +53:31:11.2 HIP 29795 2.17
2026-06-05 00:00 06:16:32.51 +53:31:00.3 HIP 29795 2.33
2026-06-05 12:00 06:16:37.40 +53:30:49.6 HIP 29795 2.69
2026-06-06 00:00 06:16:42.31 +53:30:39.1 HIP 29795 3.20
2026-06-06 12:00 06:16:47.22 +53:30:28.7 HIP 29795 3.79
2026-06-07 00:00 06:16:52.15 +53:30:18.5 HIP 29795 4.43
2026-06-07 12:00 06:16:57.10 +53:30:08.5 HIP 29795 5.11
2026-06-08 00:00 06:17:02.05 +53:29:58.7 HIP 29795 5.81
2026-06-08 12:00 06:17:07.01 +53:29:49.0 HIP 29795 6.52
2026-06-09 00:00 06:17:11.99 +53:29:39.5 HIP 29795 7.24
2026-06-09 12:00 06:17:16.97 +53:29:30.2 HIP 29795 7.97
2026-06-10 00:00 06:17:21.97 +53:29:21.0 HIP 29795 8.71
2026-06-10 12:00 06:17:26.98 +53:29:12.1 HIP 29795 9.45
2026-06-11 00:00 06:17:31.99 +53:29:03.3 HIP 29795 10.20
2026-06-11 12:00 06:17:37.02 +53:28:54.6 HIP 29795 10.95
2026-06-12 00:00 06:17:42.05 +53:28:46.2 HIP 29795 11.70
2026-06-12 12:00 06:17:47.10 +53:28:37.9 HIP 29935 12.05
2026-06-13 00:00 06:17:52.15 +53:28:29.8 HIP 29935 12.02
2026-06-13 12:00 06:17:57.21 +53:28:21.9 HIP 29935 12.03
2026-06-14 00:00 06:18:02.28 +53:28:14.2 HIP 29935 12.08
2026-06-14 12:00 06:18:07.35 +53:28:06.6 HIP 29935 12.18
2026-06-15 00:00 06:18:12.43 +53:27:59.3 HIP 29935 12.32
2026-06-15 12:00 06:18:17.52 +53:27:52.1 HIP 29935 12.50
2026-06-16 00:00 06:18:22.62 +53:27:45.0 HIP 29935 12.73
2026-06-16 12:00 06:18:27.72 +53:27:38.2 HIP 29935 12.99
2026-06-17 00:00 06:18:32.83 +53:27:31.5 HIP 29935 13.29
2026-06-17 12:00 06:18:37.94 +53:27:25.1 HIP 29935 13.63
2026-06-18 00:00 06:18:43.06 +53:27:18.8 HIP 29935 13.99
2026-06-18 12:00 06:18:48.18 +53:27:12.6 HIP 29935 14.39
2026-06-19 00:00 06:18:53.31 +53:27:06.7 HIP 29935 14.81
2026-06-19 12:00 06:18:58.44 +53:27:00.9 HIP 29935 15.26
2026-06-20 00:00 06:19:03.57 +53:26:55.3 HIP 29935 15.73
2026-06-20 12:00 06:19:08.71 +53:26:49.9 HIP 29935 16.22
2026-06-21 00:00 06:19:13.85 +53:26:44.7 HIP 29935 16.72
2026-06-21 12:00 06:19:18.99 +53:26:39.7 HIP 29935 17.25
2026-06-22 00:00 06:19:24.14 +53:26:34.8 HIP 29935 17.79