Comet Archive

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C/2019 S4 (Lemmon)

메타데이터

항목
Designation C/2019 S4 (Lemmon)
Type C
Perihelion (tp_cal, UTC) 2020-04-07T22:29:16.782720Z
Orbit solution date (soln_date, UTC) 2021-09-20T00:12:43Z
Obs used 267
NEO -
M1 8.600
K1 13.500
PC -
Discovery observation (MPC, UTC) 2019-09-17T10:53:32.640000Z
Discovery magnitude (MPC) 20.30 G
Discovery observatory (MPC) G96 · Mt. Lemmon Survey
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2020-02-18.0000000
e 0.98581834
q (au) 3.441733
a (au) 242.688906
i (deg) 92.025259
Ω (om, deg) 63.169569
ω (w, deg) 71.354510
M (ma, deg) 359.986982

밝기

C/2019 S4 (Lemmon) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (6.827 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 6.827
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
2019-09-17 2020-04-01 +21.5169 -10.890
2020-05-29 2020-12-21 -9.1806 +4.741
2020-12-21 2021-05-21 +5.8572 -4.412
2021-05-21 2021-09-12 +14.1273 -10.004

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 16:03:57.40 -36:18:04.0 HIP 120121 27.85
2026-02-03 12:00 16:03:59.98 -36:18:58.7 HIP 120121 28.52
2026-02-04 00:00 16:04:02.49 -36:19:53.5 HIP 120121 29.22
2026-02-04 12:00 16:04:04.93 -36:20:48.1 HIP 120121 29.94
2026-02-05 00:00 16:04:07.29 -36:21:42.7 HIP 120121 30.67
2026-02-05 12:00 16:04:09.57 -36:22:37.3 HIP 78652 30.88
2026-02-06 00:00 16:04:11.79 -36:23:31.8 HIP 78652 30.17
2026-02-06 12:00 16:04:13.92 -36:24:26.2 HIP 78652 29.46
2026-02-07 00:00 16:04:15.98 -36:25:20.5 HIP 78652 28.77
2026-02-07 12:00 16:04:17.96 -36:26:14.8 HIP 78652 28.09
2026-02-08 00:00 16:04:19.87 -36:27:09.0 HIP 78652 27.42
2026-02-08 12:00 16:04:21.70 -36:28:03.1 HIP 78652 26.77
2026-02-09 00:00 16:04:23.45 -36:28:57.1 HIP 78652 26.13
2026-02-09 12:00 16:04:25.12 -36:29:51.1 HIP 78652 25.51
2026-02-10 00:00 16:04:26.72 -36:30:44.9 HIP 78652 24.89
2026-02-10 12:00 16:04:28.24 -36:31:38.7 HIP 78652 24.30
2026-02-11 00:00 16:04:29.67 -36:32:32.4 HIP 78652 23.72
2026-02-11 12:00 16:04:31.04 -36:33:26.0 HIP 78652 23.15
2026-02-12 00:00 16:04:32.32 -36:34:19.5 HIP 78652 22.60
2026-02-12 12:00 16:04:33.52 -36:35:12.9 HIP 78652 22.07
2026-02-13 00:00 16:04:34.64 -36:36:06.2 HIP 78652 21.55
2026-02-13 12:00 16:04:35.68 -36:36:59.4 HIP 78652 21.05
2026-02-14 00:00 16:04:36.65 -36:37:52.6 HIP 78652 20.57
2026-02-14 12:00 16:04:37.53 -36:38:45.6 HIP 78652 20.10
2026-02-15 00:00 16:04:38.33 -36:39:38.4 HIP 78652 19.66
2026-02-15 12:00 16:04:39.05 -36:40:31.2 HIP 78652 19.23
2026-02-16 00:00 16:04:39.69 -36:41:23.9 HIP 78652 18.83
2026-02-16 12:00 16:04:40.25 -36:42:16.4 HIP 78652 18.44
2026-02-17 00:00 16:04:40.72 -36:43:08.9 HIP 78652 18.08
2026-02-17 12:00 16:04:41.12 -36:44:01.2 HIP 78652 17.74
2026-02-18 00:00 16:04:41.43 -36:44:53.3 HIP 78652 17.42
2026-02-18 12:00 16:04:41.66 -36:45:45.4 HIP 78652 17.13
2026-02-19 00:00 16:04:41.81 -36:46:37.3 HIP 78652 16.86
2026-02-19 12:00 16:04:41.87 -36:47:29.1 HIP 78652 16.61
2026-02-20 00:00 16:04:41.86 -36:48:20.7 HIP 78652 16.40
2026-02-20 12:00 16:04:41.75 -36:49:12.2 HIP 78652 16.21
2026-02-21 00:00 16:04:41.57 -36:50:03.6 HIP 78652 16.04
2026-02-21 12:00 16:04:41.31 -36:50:54.8 HIP 78652 15.91
2026-02-22 00:00 16:04:40.96 -36:51:45.9 HIP 78652 15.80
2026-02-22 12:00 16:04:40.52 -36:52:36.8 HIP 78652 15.72
2026-02-23 00:00 16:04:40.01 -36:53:27.6 HIP 78652 15.68
2026-02-23 12:00 16:04:39.41 -36:54:18.2 HIP 78652 15.66
2026-02-24 00:00 16:04:38.73 -36:55:08.7 HIP 78652 15.67