Comet Archive

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C/2018 A4 (PANSTARRS)

메타데이터

항목
Designation C/2018 A4 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-05-18T19:21:20.165760Z
Orbit solution date (soln_date, UTC) 2023-05-03T22:42:49Z
Obs used 79
NEO -
M1 8.400
K1 22.250
PC 0.030
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2018-01-15.0000000
e 0.80435873
q (au) 2.402567
a (au) 12.280471
i (deg) 3.148025
Ω (om, deg) 97.634759
ω (w, deg) 356.135345
M (ma, deg) 357.164531

밝기

C/2018 A4 (PANSTARRS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (10.536 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 10.536
n 6.000
gf 1.000
gb -0.500
k 1.000
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

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 16:35:46.16 -20:27:06.3 HIP 81287 16.74
2026-02-03 12:00 16:35:50.79 -20:27:13.6 HIP 81287 16.30
2026-02-04 00:00 16:35:55.36 -20:27:20.8 HIP 81287 15.92
2026-02-04 12:00 16:35:59.87 -20:27:27.9 HIP 81287 15.62
2026-02-05 00:00 16:36:04.33 -20:27:34.8 HIP 81287 15.39
2026-02-05 12:00 16:36:08.72 -20:27:41.6 HIP 81287 15.23
2026-02-06 00:00 16:36:13.05 -20:27:48.2 HIP 81287 15.15
2026-02-06 12:00 16:36:17.32 -20:27:54.7 HIP 81287 15.13
2026-02-07 00:00 16:36:21.53 -20:28:01.1 HIP 81287 15.17
2026-02-07 12:00 16:36:25.69 -20:28:07.3 HIP 81287 15.28
2026-02-08 00:00 16:36:29.77 -20:28:13.3 HIP 81287 15.45
2026-02-08 12:00 16:36:33.80 -20:28:19.3 HIP 81287 15.67
2026-02-09 00:00 16:36:37.77 -20:28:25.1 HIP 81287 15.95
2026-02-09 12:00 16:36:41.67 -20:28:30.7 HIP 81287 16.26
2026-02-10 00:00 16:36:45.51 -20:28:36.2 HIP 81287 16.62
2026-02-10 12:00 16:36:49.29 -20:28:41.5 HIP 81287 17.01
2026-02-11 00:00 16:36:53.01 -20:28:46.7 HIP 81287 17.43
2026-02-11 12:00 16:36:56.66 -20:28:51.8 HIP 81287 17.88
2026-02-12 00:00 16:37:00.25 -20:28:56.7 HIP 81287 18.35
2026-02-12 12:00 16:37:03.77 -20:29:01.5 HIP 81287 18.83
2026-02-13 00:00 16:37:07.23 -20:29:06.2 HIP 81287 19.33
2026-02-13 12:00 16:37:10.63 -20:29:10.6 HIP 81287 19.84
2026-02-14 00:00 16:37:13.96 -20:29:15.0 HIP 81287 20.36
2026-02-14 12:00 16:37:17.22 -20:29:19.2 HIP 81287 20.89
2026-02-15 00:00 16:37:20.42 -20:29:23.3 HIP 81287 21.42
2026-02-15 12:00 16:37:23.56 -20:29:27.2 HIP 81287 21.95
2026-02-16 00:00 16:37:26.63 -20:29:30.9 HIP 81287 22.49
2026-02-16 12:00 16:37:29.63 -20:29:34.6 HIP 81287 23.02
2026-02-17 00:00 16:37:32.56 -20:29:38.1 HIP 81287 23.55
2026-02-17 12:00 16:37:35.43 -20:29:41.4 HIP 81287 24.08
2026-02-18 00:00 16:37:38.24 -20:29:44.6 HIP 81287 24.60
2026-02-18 12:00 16:37:40.97 -20:29:47.6 HIP 81287 25.12
2026-02-19 00:00 16:37:43.64 -20:29:50.5 HIP 81287 25.63
2026-02-19 12:00 16:37:46.24 -20:29:53.3 HIP 81287 26.13
2026-02-20 00:00 16:37:48.78 -20:29:55.9 HIP 81287 26.62
2026-02-20 12:00 16:37:51.24 -20:29:58.4 HIP 81287 27.11
2026-02-21 00:00 16:37:53.64 -20:30:00.7 HIP 81287 27.58
2026-02-21 12:00 16:37:55.97 -20:30:02.9 HIP 81287 28.05
2026-02-22 00:00 16:37:58.23 -20:30:05.0 HIP 81287 28.50
2026-02-22 12:00 16:38:00.42 -20:30:06.9 HIP 81287 28.95
2026-02-23 00:00 16:38:02.55 -20:30:08.7 HIP 81287 29.38
2026-02-23 12:00 16:38:04.60 -20:30:10.3 HIP 81287 29.81
2026-02-24 00:00 16:38:06.59 -20:30:11.8 HIP 81325 30.17