C/2017 U4 (PANSTARRS)

메타데이터

항목
Designation C/2017 U4 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-09-25T16:38:00.893760Z
Orbit solution date (soln_date, UTC) 2023-02-13T23:12:42Z
Obs used 85
NEO -
M1 7.100
K1 10.750
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2018-01-03.0000000
e 1.00304382
q (au) 7.724158
a (au) -2537.649728
i (deg) 158.225721
Ω (om, deg) 245.952559
ω (w, deg) 159.177100
M (ma, deg) -0.002049

밝기

C/2017 U4 (PANSTARRS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (2.306 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 2.306
n 6.000
gf 0.992
gb -1.000
k 1.000
δ90 9.972
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)
2026-03-26 00:00 00:07:39.24 -20:55:23.0 HIP 553 16.08
2026-03-26 12:00 00:07:44.30 -20:55:00.4 HIP 553 17.24
2026-03-27 00:00 00:07:49.37 -20:54:38.1 HIP 553 18.41
2026-03-27 12:00 00:07:54.42 -20:54:16.1 HIP 553 19.58
2026-03-28 00:00 00:07:59.47 -20:53:54.4 HIP 553 20.76
2026-03-28 12:00 00:08:04.52 -20:53:33.1 HIP 553 21.94
2026-03-29 00:00 00:08:09.56 -20:53:12.1 HIP 724 22.41
2026-03-29 12:00 00:08:14.59 -20:52:51.4 HIP 724 22.12
2026-03-30 00:00 00:08:19.62 -20:52:31.1 HIP 724 21.90
2026-03-30 12:00 00:08:24.64 -20:52:11.1 HIP 724 21.75
2026-03-31 00:00 00:08:29.65 -20:51:51.4 HIP 724 21.65
2026-03-31 12:00 00:08:34.66 -20:51:32.1 HIP 724 21.62
2026-04-01 00:00 00:08:39.65 -20:51:13.2 HIP 724 21.65
2026-04-01 12:00 00:08:44.64 -20:50:54.6 HIP 724 21.74
2026-04-02 00:00 00:08:49.62 -20:50:36.3 HIP 724 21.89
2026-04-02 12:00 00:08:54.59 -20:50:18.4 HIP 724 22.10
2026-04-03 00:00 00:08:59.55 -20:50:00.8 HIP 724 22.36
2026-04-03 12:00 00:09:04.50 -20:49:43.6 HIP 724 22.68
2026-04-04 00:00 00:09:09.44 -20:49:26.8 HIP 724 23.06
2026-04-04 12:00 00:09:14.37 -20:49:10.3 HIP 724 23.47
2026-04-05 00:00 00:09:19.29 -20:48:54.1 HIP 724 23.94
2026-04-05 12:00 00:09:24.19 -20:48:38.3 HIP 724 24.44
2026-04-06 00:00 00:09:29.09 -20:48:22.9 HIP 724 24.99
2026-04-06 12:00 00:09:33.97 -20:48:07.9 HIP 911 24.63
2026-04-07 00:00 00:09:38.84 -20:47:53.2 HIP 911 23.46
2026-04-07 12:00 00:09:43.70 -20:47:38.9 HIP 911 22.30
2026-04-08 00:00 00:09:48.54 -20:47:24.9 HIP 911 21.15
2026-04-08 12:00 00:09:53.37 -20:47:11.3 HIP 911 20.00
2026-04-09 00:00 00:09:58.18 -20:46:58.1 HIP 911 18.85
2026-04-09 12:00 00:10:02.98 -20:46:45.3 HIP 911 17.71
2026-04-10 00:00 00:10:07.77 -20:46:32.9 HIP 911 16.57
2026-04-10 12:00 00:10:12.54 -20:46:20.8 HIP 911 15.44
2026-04-11 00:00 00:10:17.29 -20:46:09.1 HIP 911 14.31
2026-04-11 12:00 00:10:22.03 -20:45:57.8 HIP 911 13.19
2026-04-12 00:00 00:10:26.75 -20:45:46.9 HIP 911 12.07
2026-04-12 12:00 00:10:31.46 -20:45:36.4 HIP 911 10.95
2026-04-13 00:00 00:10:36.15 -20:45:26.2 HIP 911 9.85
2026-04-13 12:00 00:10:40.82 -20:45:16.5 HIP 911 8.74
2026-04-14 00:00 00:10:45.47 -20:45:07.1 HIP 911 7.65
2026-04-14 12:00 00:10:50.10 -20:44:58.2 HIP 911 6.56
2026-04-15 00:00 00:10:54.71 -20:44:49.6 HIP 911 5.48
2026-04-15 12:00 00:10:59.31 -20:44:41.4 HIP 911 4.40
2026-04-16 00:00 00:11:03.88 -20:44:33.7 HIP 911 3.34