81P/Wild 2

메타데이터

항목
Designation 81P/Wild 2
Type P
Perihelion (tp_cal, UTC) 2022-12-15T18:49:47.694720Z
Orbit solution date (soln_date, UTC) 2024-09-12T12:06:16Z
Obs used 2795
NEO -
M1 9.800
K1 12.500
PC 0.030
Osculating 궤도요소
항목
Epoch (epoch_cal, TDB) 2019-11-21.0000000
e 0.53739891
q (au) 1.595856
a (au) 3.449746
i (deg) 3.237004
Ω (om, deg) 136.110221
ω (w, deg) 41.725231
M (ma, deg) 187.596681

밝기

81P/Wild 2 · Magnitude (Full range)

산란 + 전체 선형

$$ M_a = (9.658 + 5.323\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목
H0 9.658
n 5.323
gf 0.800
gb -0.500
k 0.894
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
2020-09-17 2022-12-15 +5.7911 -3.099
2022-12-15 2023-03-16 +32.4001 -7.929
2023-03-16 2024-09-07 -2.8049 +1.007

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 00:02:42.06 -01:43:54.3 HIP 134 38.55
2026-03-26 12:00 00:03:04.49 -01:41:32.9 HIP 438 34.03
2026-03-27 00:00 00:03:26.91 -01:39:11.6 HIP 438 29.13
2026-03-27 12:00 00:03:49.32 -01:36:50.5 HIP 438 24.76
2026-03-28 00:00 00:04:11.71 -01:34:29.5 HIP 438 21.24
2026-03-28 12:00 00:04:34.10 -01:32:08.6 HIP 438 19.06
2026-03-29 00:00 00:04:56.48 -01:29:47.8 HIP 438 18.68
2026-03-29 12:00 00:05:18.85 -01:27:27.2 HIP 521 19.92
2026-03-30 00:00 00:05:41.20 -01:25:06.7 HIP 521 14.32
2026-03-30 12:00 00:06:03.55 -01:22:46.4 HIP 521 9.30
2026-03-31 00:00 00:06:25.88 -01:20:26.3 HIP 521 6.42
2026-03-31 12:00 00:06:48.19 -01:18:06.2 HIP 521 8.31
2026-04-01 00:00 00:07:10.50 -01:15:46.4 HIP 521 13.04
2026-04-01 12:00 00:07:32.78 -01:13:26.7 HIP 521 18.54
2026-04-02 00:00 00:07:55.06 -01:11:07.2 HIP 521 24.30
2026-04-02 12:00 00:08:17.32 -01:08:47.8 HIP 752 27.45
2026-04-03 00:00 00:08:39.56 -01:06:28.7 HIP 752 22.92
2026-04-03 12:00 00:09:01.78 -01:04:09.7 HIP 752 19.23
2026-04-04 00:00 00:09:23.99 -01:01:50.8 HIP 752 16.94
2026-04-04 12:00 00:09:46.18 -00:59:32.2 HIP 752 16.63
2026-04-05 00:00 00:10:08.36 -00:57:13.8 HIP 752 18.38
2026-04-05 12:00 00:10:30.51 -00:54:55.5 HIP 925 19.60
2026-04-06 00:00 00:10:52.65 -00:52:37.5 HIP 925 17.61
2026-04-06 12:00 00:11:14.77 -00:50:19.6 HIP 925 17.55
2026-04-07 00:00 00:11:36.86 -00:48:02.0 HIP 925 19.42
2026-04-07 12:00 00:11:58.94 -00:45:44.6 HIP 925 22.76
2026-04-08 00:00 00:12:20.99 -00:43:27.3 HIP 925 27.01
2026-04-08 12:00 00:12:43.03 -00:41:10.3 HIP 968 29.49
2026-04-09 00:00 00:13:05.04 -00:38:53.6 HIP 968 30.01
2026-04-09 12:00 00:13:27.03 -00:36:37.0 HIP 1082 27.76
2026-04-10 00:00 00:13:48.99 -00:34:20.7 HIP 1189 22.25
2026-04-10 12:00 00:14:10.93 -00:32:04.6 HIP 1189 17.01
2026-04-11 00:00 00:14:32.85 -00:29:48.8 HIP 1189 12.41
2026-04-11 12:00 00:14:54.74 -00:27:33.2 HIP 1189 9.45
2026-04-12 00:00 00:15:16.60 -00:25:17.8 HIP 1189 9.72
2026-04-12 12:00 00:15:38.44 -00:23:02.8 HIP 1189 13.02
2026-04-13 00:00 00:16:00.25 -00:20:47.9 HIP 1189 17.72
2026-04-13 12:00 00:16:22.04 -00:18:33.4 HIP 1189 22.98
2026-04-14 00:00 00:16:43.79 -00:16:19.1 HIP 1189 28.47
2026-04-14 12:00 00:17:05.52 -00:14:05.0 HIP 1397 33.85
2026-04-15 00:00 00:17:27.21 -00:11:51.3 HIP 1397 31.12
2026-04-15 12:00 00:17:48.88 -00:09:37.8 HIP 1397 29.32
2026-04-16 00:00 00:18:10.52 -00:07:24.7 HIP 1397 28.64