C/2017 X1 (PANSTARRS)

메타데이터

항목
Designation C/2017 X1 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-06-14T10:45:05.999040Z
Orbit solution date (soln_date, UTC) 2021-09-04T23:42:57Z
Obs used 127
NEO -
M1 7.000
K1 13.500
PC 0.030
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2018-02-14.0000000
e 0.85110910
q (au) 4.662645
a (au) 31.315852
i (deg) 31.310998
Ω (om, deg) 251.126772
ω (w, deg) 283.106326
M (ma, deg) 359.322581

밝기

C/2017 X1 (PANSTARRS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (5.561 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 5.561
n 6.000
gf 1.000
gb -1.000
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

잔차 (구간 선형)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

시작일 (UTC) 끝 (UTC) a b
2017-02-12 2018-06-07 +17.3813 -12.086
2018-07-17 2019-07-25 -2.0175 +1.329

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

천체력

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-03-26 00:00 19:42:32.73 +01:11:57.9 HIP 96908 8.64
2026-03-26 12:00 19:42:35.96 +01:12:50.8 HIP 96908 9.58
2026-03-27 00:00 19:42:39.13 +01:13:43.7 HIP 96908 10.56
2026-03-27 12:00 19:42:42.26 +01:14:36.5 HIP 96908 11.56
2026-03-28 00:00 19:42:45.32 +01:15:29.4 HIP 96908 12.58
2026-03-28 12:00 19:42:48.34 +01:16:22.2 HIP 96908 13.61
2026-03-29 00:00 19:42:51.29 +01:17:15.1 HIP 96993 14.63
2026-03-29 12:00 19:42:54.20 +01:18:07.9 HIP 96993 13.78
2026-03-30 00:00 19:42:57.04 +01:19:00.7 HIP 96993 12.98
2026-03-30 12:00 19:42:59.84 +01:19:53.5 HIP 96993 12.23
2026-03-31 00:00 19:43:02.58 +01:20:46.3 HIP 96993 11.53
2026-03-31 12:00 19:43:05.26 +01:21:39.1 HIP 96993 10.90
2026-04-01 00:00 19:43:07.88 +01:22:31.8 HIP 96993 10.34
2026-04-01 12:00 19:43:10.45 +01:23:24.5 HIP 96993 9.87
2026-04-02 00:00 19:43:12.97 +01:24:17.2 HIP 96993 9.49
2026-04-02 12:00 19:43:15.43 +01:25:09.8 HIP 96993 9.22
2026-04-03 00:00 19:43:17.83 +01:26:02.4 HIP 96993 9.05
2026-04-03 12:00 19:43:20.18 +01:26:55.0 HIP 96993 8.99
2026-04-04 00:00 19:43:22.47 +01:27:47.5 HIP 96993 9.05
2026-04-04 12:00 19:43:24.70 +01:28:40.0 HIP 96993 9.21
2026-04-05 00:00 19:43:26.88 +01:29:32.4 HIP 96993 9.47
2026-04-05 12:00 19:43:29.00 +01:30:24.8 HIP 96993 9.82
2026-04-06 00:00 19:43:31.07 +01:31:17.1 HIP 96993 10.24
2026-04-06 12:00 19:43:33.07 +01:32:09.4 HIP 96993 10.73
2026-04-07 00:00 19:43:35.02 +01:33:01.6 HIP 96993 11.27
2026-04-07 12:00 19:43:36.92 +01:33:53.7 HIP 96993 11.86
2026-04-08 00:00 19:43:38.75 +01:34:45.8 HIP 96993 12.48
2026-04-08 12:00 19:43:40.53 +01:35:37.8 HIP 96993 13.14
2026-04-09 00:00 19:43:42.25 +01:36:29.8 HIP 96993 13.81
2026-04-09 12:00 19:43:43.91 +01:37:21.6 HIP 96993 14.51
2026-04-10 00:00 19:43:45.52 +01:38:13.4 HIP 96993 15.22
2026-04-10 12:00 19:43:47.06 +01:39:05.1 HIP 96993 15.94
2026-04-11 00:00 19:43:48.55 +01:39:56.8 HIP 96993 16.68
2026-04-11 12:00 19:43:49.98 +01:40:48.3 HIP 96993 17.41
2026-04-12 00:00 19:43:51.36 +01:41:39.7 HIP 96993 18.16
2026-04-12 12:00 19:43:52.67 +01:42:31.1 HIP 96993 18.90
2026-04-13 00:00 19:43:53.92 +01:43:22.3 HIP 96993 19.65
2026-04-13 12:00 19:43:55.12 +01:44:13.5 HIP 96993 20.40
2026-04-14 00:00 19:43:56.26 +01:45:04.5 HIP 96993 21.15
2026-04-14 12:00 19:43:57.34 +01:45:55.5 HIP 96993 21.89
2026-04-15 00:00 19:43:58.36 +01:46:46.3 HIP 96993 22.64
2026-04-15 12:00 19:43:59.32 +01:47:37.1 HIP 96993 23.38
2026-04-16 00:00 19:44:00.23 +01:48:27.7 HIP 96993 24.12