Comet Archive

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C/2021 P2 (PANSTARRS)

메타데이터

항목
Designation C/2021 P2 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2023-01-22T16:20:24.480960Z
Orbit solution date (soln_date, UTC) 2025-06-26T10:12:45Z
Obs used 408
NEO -
M1 7.500
K1 11.500
PC -
Discovery observation (MPC, UTC) 2021-08-07T12:35:04.617600Z
Discovery magnitude (MPC) 21.50 w
Discovery observatory (MPC) F51 · Pan-STARRS 1, Haleakala
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2023-02-01.0000000
e 0.99795112
q (au) 5.069092
a (au) 2474.083378
i (deg) 150.063521
Ω (om, deg) 32.079344
ω (w, deg) 76.687326
M (ma, deg) 0.000075

밝기

C/2021 P2 (PANSTARRS) · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (5.684 + 5.099\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 5.684
n 5.099
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
2021-06-19 2022-11-22 +5.2257 -3.680
2023-04-26 2025-05-21 -4.1164 +2.668

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 15:34:47.94 -10:13:33.6 HIP 76219 13.39
2026-02-03 12:00 15:34:46.07 -10:13:27.9 HIP 76219 13.01
2026-02-04 00:00 15:34:44.10 -10:13:21.8 HIP 76219 12.61
2026-02-04 12:00 15:34:42.01 -10:13:15.3 HIP 76219 12.20
2026-02-05 00:00 15:34:39.82 -10:13:08.3 HIP 76219 11.77
2026-02-05 12:00 15:34:37.52 -10:13:00.9 HIP 76219 11.33
2026-02-06 00:00 15:34:35.11 -10:12:53.0 HIP 76219 10.88
2026-02-06 12:00 15:34:32.58 -10:12:44.7 HIP 76219 10.43
2026-02-07 00:00 15:34:29.95 -10:12:36.0 HIP 76219 9.98
2026-02-07 12:00 15:34:27.20 -10:12:26.9 HIP 76219 9.54
2026-02-08 00:00 15:34:24.35 -10:12:17.3 HIP 76219 9.11
2026-02-08 12:00 15:34:21.38 -10:12:07.2 HIP 76219 8.70
2026-02-09 00:00 15:34:18.30 -10:11:56.8 HIP 76219 8.33
2026-02-09 12:00 15:34:15.10 -10:11:45.9 HIP 76219 8.01
2026-02-10 00:00 15:34:11.79 -10:11:34.6 HIP 76219 7.75
2026-02-10 12:00 15:34:08.37 -10:11:22.8 HIP 76219 7.56
2026-02-11 00:00 15:34:04.84 -10:11:10.7 HIP 76219 7.47
2026-02-11 12:00 15:34:01.19 -10:10:58.1 HIP 76219 7.49
2026-02-12 00:00 15:33:57.42 -10:10:45.0 HIP 76219 7.63
2026-02-12 12:00 15:33:53.54 -10:10:31.6 HIP 76219 7.89
2026-02-13 00:00 15:33:49.55 -10:10:17.7 HIP 76219 8.27
2026-02-13 12:00 15:33:45.44 -10:10:03.4 HIP 76219 8.76
2026-02-14 00:00 15:33:41.21 -10:09:48.7 HIP 76219 9.37
2026-02-14 12:00 15:33:36.87 -10:09:33.5 HIP 76219 10.07
2026-02-15 00:00 15:33:32.41 -10:09:18.0 HIP 76219 10.85
2026-02-15 12:00 15:33:27.83 -10:09:02.0 HIP 76219 11.72
2026-02-16 00:00 15:33:23.14 -10:08:45.6 HIP 76219 12.66
2026-02-16 12:00 15:33:18.33 -10:08:28.8 HIP 76219 13.66
2026-02-17 00:00 15:33:13.41 -10:08:11.5 HIP 76219 14.72
2026-02-17 12:00 15:33:08.37 -10:07:53.9 HIP 76219 15.83
2026-02-18 00:00 15:33:03.21 -10:07:35.8 HIP 76219 16.99
2026-02-18 12:00 15:32:57.93 -10:07:17.4 HIP 76219 18.20
2026-02-19 00:00 15:32:52.53 -10:06:58.5 HIP 76219 19.45
2026-02-19 12:00 15:32:47.02 -10:06:39.2 HIP 76219 20.74
2026-02-20 00:00 15:32:41.39 -10:06:19.5 HIP 76079 20.81
2026-02-20 12:00 15:32:35.64 -10:05:59.4 HIP 76079 20.79
2026-02-21 00:00 15:32:29.77 -10:05:38.9 HIP 76079 20.88
2026-02-21 12:00 15:32:23.78 -10:05:18.1 HIP 76079 21.07
2026-02-22 00:00 15:32:17.68 -10:04:56.8 HIP 76079 21.37
2026-02-22 12:00 15:32:11.46 -10:04:35.1 HIP 76079 21.79
2026-02-23 00:00 15:32:05.12 -10:04:13.0 HIP 76079 22.32
2026-02-23 12:00 15:31:58.66 -10:03:50.6 HIP 76079 22.97
2026-02-24 00:00 15:31:52.09 -10:03:27.7 HIP 76079 23.72