Comet Archive

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C/2018 N1 (NEOWISE)

메타데이터

항목
Designation C/2018 N1 (NEOWISE)
Type C
Perihelion (tp_cal, UTC) 2018-08-01T23:35:12.114240Z
Orbit solution date (soln_date, UTC) 2022-06-20T23:12:32Z
Obs used 263
NEO -
M1 14.800
K1 11.750
PC 0.030
Discovery observation (MPC, UTC) 2018-07-02T08:53:36.384000Z
Discovery magnitude (MPC) 16.00 R
Discovery observatory (MPC) C51 · WISE
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2018-07-23.0000000
e 0.99690168
q (au) 1.307382
a (au) 421.964782
i (deg) 159.444331
Ω (om, deg) 292.438182
ω (w, deg) 354.558421
M (ma, deg) 359.998865

밝기

C/2018 N1 (NEOWISE) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (13.856 + 5.455\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 13.856
n 5.455
gf 0.800
gb -0.500
k 0.957
δ90 1.000
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
2017-12-15 2018-08-01 +5.8573 -2.511
2018-08-02 2018-10-06 -17.1024 -0.661

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 10:10:13.17 +24:11:25.3 HIP 49842 19.29
2026-02-03 12:00 10:10:06.51 +24:12:02.4 HIP 49842 20.35
2026-02-04 00:00 10:09:59.83 +24:12:39.4 HIP 49842 21.48
2026-02-04 12:00 10:09:53.14 +24:13:16.2 HIP 49677 20.12
2026-02-05 00:00 10:09:46.43 +24:13:53.0 HIP 49677 18.48
2026-02-05 12:00 10:09:39.71 +24:14:29.6 HIP 49677 16.84
2026-02-06 00:00 10:09:32.97 +24:15:06.1 HIP 49677 15.21
2026-02-06 12:00 10:09:26.22 +24:15:42.4 HIP 49677 13.58
2026-02-07 00:00 10:09:19.46 +24:16:18.7 HIP 49677 11.95
2026-02-07 12:00 10:09:12.68 +24:16:54.7 HIP 49677 10.32
2026-02-08 00:00 10:09:05.89 +24:17:30.7 HIP 49677 8.71
2026-02-08 12:00 10:08:59.10 +24:18:06.5 HIP 49677 7.11
2026-02-09 00:00 10:08:52.29 +24:18:42.1 HIP 49677 5.55
2026-02-09 12:00 10:08:45.47 +24:19:17.6 HIP 49677 4.06
2026-02-10 00:00 10:08:38.64 +24:19:53.0 HIP 49677 2.79
2026-02-10 12:00 10:08:31.80 +24:20:28.1 HIP 49677 2.13
2026-02-11 00:00 10:08:24.96 +24:21:03.2 HIP 49677 2.61
2026-02-11 12:00 10:08:18.10 +24:21:38.0 HIP 49677 3.83
2026-02-12 00:00 10:08:11.24 +24:22:12.7 HIP 49677 5.30
2026-02-12 12:00 10:08:04.38 +24:22:47.2 HIP 49677 6.85
2026-02-13 00:00 10:07:57.50 +24:23:21.5 HIP 49677 8.45
2026-02-13 12:00 10:07:50.62 +24:23:55.7 HIP 49677 10.07
2026-02-14 00:00 10:07:43.74 +24:24:29.7 HIP 49677 11.70
2026-02-14 12:00 10:07:36.85 +24:25:03.5 HIP 49677 13.34
2026-02-15 00:00 10:07:29.96 +24:25:37.1 HIP 49677 14.99
2026-02-15 12:00 10:07:23.07 +24:26:10.5 HIP 49677 16.64
2026-02-16 00:00 10:07:16.17 +24:26:43.8 HIP 49677 18.29
2026-02-16 12:00 10:07:09.27 +24:27:16.8 HIP 49677 19.94
2026-02-17 00:00 10:07:02.37 +24:27:49.6 HIP 49677 21.59
2026-02-17 12:00 10:06:55.47 +24:28:22.3 HIP 49677 23.24
2026-02-18 00:00 10:06:48.57 +24:28:54.7 HIP 49677 24.89
2026-02-18 12:00 10:06:41.67 +24:29:26.9 HIP 49430 26.19
2026-02-19 00:00 10:06:34.77 +24:29:58.9 HIP 49430 24.78
2026-02-19 12:00 10:06:27.88 +24:30:30.7 HIP 49430 23.41
2026-02-20 00:00 10:06:20.98 +24:31:02.3 HIP 49430 22.07
2026-02-20 12:00 10:06:14.09 +24:31:33.7 HIP 49430 20.79
2026-02-21 00:00 10:06:07.20 +24:32:04.8 HIP 49430 19.57
2026-02-21 12:00 10:06:00.32 +24:32:35.7 HIP 49430 18.41
2026-02-22 00:00 10:05:53.44 +24:33:06.4 HIP 49430 17.34
2026-02-22 12:00 10:05:46.57 +24:33:36.9 HIP 49430 16.37
2026-02-23 00:00 10:05:39.70 +24:34:07.1 HIP 49430 15.52
2026-02-23 12:00 10:05:32.84 +24:34:37.1 HIP 49430 14.80
2026-02-24 00:00 10:05:25.99 +24:35:06.8 HIP 49430 14.24