Comet Archive

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C/1979 Y1 (Bradfield)

메타데이터

항목
Designation C/1979 Y1 (Bradfield)
Type C
Perihelion (tp_cal, UTC) 1979-12-21T14:38:01.069440Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:29Z
Obs used 127
NEO -
M1 8.500
K1 14.000
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 1980-01-25.0000000
e 0.98803814
q (au) 0.545301
a (au) 45.586646
i (deg) 148.602533
Ω (om, deg) 103.215535
ω (w, deg) 257.609730
M (ma, deg) 0.110124

밝기

C/1979 Y1 (Bradfield) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (8.331 + 4.383\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 8.331
n 4.383
gf 0.800
gb -1.000
k 0.800
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
1979-12-26 1980-01-04 -10.3165 -2.880
1980-01-04 1980-01-17 +20.4042 +3.298
1980-01-17 1980-01-25 -11.5672 +0.125
1980-01-25 1980-03-02 -3.9664 +0.215
1980-03-02 1980-03-17 -5.5222 +0.290

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

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 01:16:52.41 +40:09:14.0 HIP 6120 19.90
2026-02-03 12:00 01:16:53.31 +40:09:02.8 HIP 6120 19.77
2026-02-04 00:00 01:16:54.23 +40:08:51.8 HIP 6120 19.64
2026-02-04 12:00 01:16:55.18 +40:08:40.9 HIP 6120 19.51
2026-02-05 00:00 01:16:56.14 +40:08:30.2 HIP 6120 19.37
2026-02-05 12:00 01:16:57.12 +40:08:19.6 HIP 6120 19.24
2026-02-06 00:00 01:16:58.12 +40:08:09.1 HIP 6120 19.10
2026-02-06 12:00 01:16:59.14 +40:07:58.7 HIP 6120 18.97
2026-02-07 00:00 01:17:00.18 +40:07:48.5 HIP 6120 18.83
2026-02-07 12:00 01:17:01.23 +40:07:38.5 HIP 6120 18.69
2026-02-08 00:00 01:17:02.30 +40:07:28.6 HIP 6120 18.55
2026-02-08 12:00 01:17:03.40 +40:07:18.8 HIP 6120 18.40
2026-02-09 00:00 01:17:04.51 +40:07:09.1 HIP 6120 18.26
2026-02-09 12:00 01:17:05.64 +40:06:59.6 HIP 6120 18.11
2026-02-10 00:00 01:17:06.78 +40:06:50.3 HIP 6120 17.97
2026-02-10 12:00 01:17:07.95 +40:06:41.1 HIP 6120 17.82
2026-02-11 00:00 01:17:09.13 +40:06:32.0 HIP 6120 17.67
2026-02-11 12:00 01:17:10.33 +40:06:23.1 HIP 6120 17.52
2026-02-12 00:00 01:17:11.55 +40:06:14.3 HIP 6120 17.36
2026-02-12 12:00 01:17:12.79 +40:06:05.7 HIP 6120 17.21
2026-02-13 00:00 01:17:14.04 +40:05:57.2 HIP 6120 17.06
2026-02-13 12:00 01:17:15.31 +40:05:48.9 HIP 6120 16.90
2026-02-14 00:00 01:17:16.60 +40:05:40.7 HIP 6120 16.75
2026-02-14 12:00 01:17:17.91 +40:05:32.6 HIP 6120 16.59
2026-02-15 00:00 01:17:19.23 +40:05:24.8 HIP 6120 16.43
2026-02-15 12:00 01:17:20.57 +40:05:17.0 HIP 6120 16.27
2026-02-16 00:00 01:17:21.93 +40:05:09.4 HIP 6120 16.12
2026-02-16 12:00 01:17:23.30 +40:05:02.0 HIP 6120 15.96
2026-02-17 00:00 01:17:24.69 +40:04:54.7 HIP 6120 15.80
2026-02-17 12:00 01:17:26.10 +40:04:47.6 HIP 6120 15.64
2026-02-18 00:00 01:17:27.52 +40:04:40.6 HIP 6120 15.48
2026-02-18 12:00 01:17:28.96 +40:04:33.7 HIP 6120 15.32
2026-02-19 00:00 01:17:30.42 +40:04:27.1 HIP 6120 15.16
2026-02-19 12:00 01:17:31.89 +40:04:20.5 HIP 6120 15.00
2026-02-20 00:00 01:17:33.37 +40:04:14.2 HIP 6120 14.84
2026-02-20 12:00 01:17:34.88 +40:04:07.9 HIP 6120 14.68
2026-02-21 00:00 01:17:36.40 +40:04:01.9 HIP 6120 14.53
2026-02-21 12:00 01:17:37.93 +40:03:56.0 HIP 6120 14.37
2026-02-22 00:00 01:17:39.48 +40:03:50.2 HIP 6120 14.22
2026-02-22 12:00 01:17:41.04 +40:03:44.6 HIP 6120 14.06
2026-02-23 00:00 01:17:42.62 +40:03:39.1 HIP 6120 13.91
2026-02-23 12:00 01:17:44.22 +40:03:33.8 HIP 6120 13.76
2026-02-24 00:00 01:17:45.83 +40:03:28.7 HIP 6120 13.61