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C/1921 E1 (Reid)

메타데이터

항목
Designation C/1921 E1 (Reid)
Type C
Perihelion (tp_cal, UTC) 1921-05-10T10:47:48.370560Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:02Z
Obs used 20
NEO -
M1 -
K1 -
PC -
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 1921-04-10.0000000
e 1.00057570
q (au) 1.008454
a (au) -1751.685065
i (deg) 132.188784
Ω (om, deg) 269.441203
ω (w, deg) 64.493054
M (ma, deg) -0.000409

밝기

C/1921 E1 (Reid) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 -
n -
gf -
gb -
k -
δ90 -
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 03:36:53.79 -18:39:51.6 HIP 16799 11.86
2026-02-03 12:00 03:36:53.56 -18:39:43.7 HIP 16799 11.74
2026-02-04 00:00 03:36:53.34 -18:39:35.7 HIP 16799 11.62
2026-02-04 12:00 03:36:53.13 -18:39:27.7 HIP 16799 11.50
2026-02-05 00:00 03:36:52.93 -18:39:19.6 HIP 16799 11.39
2026-02-05 12:00 03:36:52.73 -18:39:11.5 HIP 16799 11.28
2026-02-06 00:00 03:36:52.55 -18:39:03.4 HIP 16799 11.17
2026-02-06 12:00 03:36:52.37 -18:38:55.3 HIP 16799 11.06
2026-02-07 00:00 03:36:52.20 -18:38:47.1 HIP 16799 10.95
2026-02-07 12:00 03:36:52.04 -18:38:38.8 HIP 16799 10.85
2026-02-08 00:00 03:36:51.89 -18:38:30.6 HIP 16799 10.74
2026-02-08 12:00 03:36:51.75 -18:38:22.3 HIP 16799 10.65
2026-02-09 00:00 03:36:51.61 -18:38:14.0 HIP 16799 10.55
2026-02-09 12:00 03:36:51.49 -18:38:05.6 HIP 16799 10.45
2026-02-10 00:00 03:36:51.37 -18:37:57.2 HIP 16799 10.36
2026-02-10 12:00 03:36:51.26 -18:37:48.8 HIP 16799 10.27
2026-02-11 00:00 03:36:51.16 -18:37:40.4 HIP 16799 10.19
2026-02-11 12:00 03:36:51.07 -18:37:31.9 HIP 16799 10.10
2026-02-12 00:00 03:36:50.99 -18:37:23.4 HIP 16799 10.02
2026-02-12 12:00 03:36:50.91 -18:37:14.9 HIP 16799 9.95
2026-02-13 00:00 03:36:50.85 -18:37:06.3 HIP 16799 9.87
2026-02-13 12:00 03:36:50.79 -18:36:57.7 HIP 16799 9.80
2026-02-14 00:00 03:36:50.74 -18:36:49.1 HIP 16799 9.73
2026-02-14 12:00 03:36:50.70 -18:36:40.5 HIP 16799 9.67
2026-02-15 00:00 03:36:50.67 -18:36:31.8 HIP 16799 9.61
2026-02-15 12:00 03:36:50.65 -18:36:23.2 HIP 16799 9.55
2026-02-16 00:00 03:36:50.63 -18:36:14.5 HIP 16799 9.50
2026-02-16 12:00 03:36:50.63 -18:36:05.7 HIP 16799 9.45
2026-02-17 00:00 03:36:50.63 -18:35:57.0 HIP 16799 9.40
2026-02-17 12:00 03:36:50.64 -18:35:48.2 HIP 16799 9.36
2026-02-18 00:00 03:36:50.66 -18:35:39.5 HIP 16799 9.32
2026-02-18 12:00 03:36:50.69 -18:35:30.7 HIP 16799 9.29
2026-02-19 00:00 03:36:50.73 -18:35:21.8 HIP 16799 9.26
2026-02-19 12:00 03:36:50.77 -18:35:13.0 HIP 16799 9.23
2026-02-20 00:00 03:36:50.83 -18:35:04.2 HIP 16799 9.21
2026-02-20 12:00 03:36:50.89 -18:34:55.3 HIP 16799 9.19
2026-02-21 00:00 03:36:50.96 -18:34:46.4 HIP 16799 9.18
2026-02-21 12:00 03:36:51.04 -18:34:37.5 HIP 16799 9.17
2026-02-22 00:00 03:36:51.13 -18:34:28.6 HIP 16799 9.17
2026-02-22 12:00 03:36:51.23 -18:34:19.7 HIP 16799 9.17
2026-02-23 00:00 03:36:51.33 -18:34:10.8 HIP 16799 9.17
2026-02-23 12:00 03:36:51.45 -18:34:01.8 HIP 16799 9.18
2026-02-24 00:00 03:36:51.57 -18:33:52.9 HIP 16799 9.19