메타데이터

항목	값
Designation	65P/Gunn
Type	P
Perihelion (tp_cal, UTC)	2017-10-17T19:31:35.273280Z
Orbit solution date (soln_date, UTC)	2026-07-20T21:56:35Z
Obs used	3136
NEO	-
M1	11.600
K1	6.500
PC	-

Osculating 궤도요소

항목	값
Epoch (epoch_cal, TDB)	2020-08-20.0000000
e	0.24981305
q (au)	2.914034
a (au)	3.884410
i (deg)	9.182676
Ω (om, deg)	62.020549
ω (w, deg)	213.811389
M (ma, deg)	133.528294

밝기

산란 + 전체 선형

$$ M_a = (11.214 + 2.704\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목	값
H0	11.214
n	2.704
gf	0.851
gb	-0.500
k	0.951
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
2021-12-05	2024-04-01	-7.0757	+3.602
2024-04-01	2026-07-23	+5.0768	-2.814

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

찾아보기

천체력

Date/Time (UTC)	RA (J2000)	Dec (J2000)	Nearest HIP	Dist from HIP (arcmin)
2026-07-29 00:00	00:53:48.77	-05:09:35.3	HIP 4308	26.36
2026-07-29 12:00	00:53:52.61	-05:10:11.7	HIP 4308	25.23
2026-07-30 00:00	00:53:56.18	-05:10:49.6	HIP 4308	24.15
2026-07-30 12:00	00:53:59.48	-05:11:29.0	HIP 4308	23.09
2026-07-31 00:00	00:54:02.51	-05:12:09.9	HIP 4308	22.08
2026-07-31 12:00	00:54:05.27	-05:12:52.3	HIP 4308	21.10
2026-08-01 00:00	00:54:07.76	-05:13:36.2	HIP 4308	20.16
2026-08-01 12:00	00:54:09.98	-05:14:21.7	HIP 4308	19.25
2026-08-02 00:00	00:54:11.93	-05:15:08.6	HIP 4308	18.40
2026-08-02 12:00	00:54:13.60	-05:15:57.0	HIP 4308	17.59
2026-08-03 00:00	00:54:15.00	-05:16:46.9	HIP 4308	16.83
2026-08-03 12:00	00:54:16.13	-05:17:38.2	HIP 4308	16.13
2026-08-04 00:00	00:54:16.98	-05:18:31.1	HIP 4308	15.50
2026-08-04 12:00	00:54:17.56	-05:19:25.4	HIP 4308	14.95
2026-08-05 00:00	00:54:17.86	-05:20:21.1	HIP 4308	14.48
2026-08-05 12:00	00:54:17.89	-05:21:18.3	HIP 4308	14.13
2026-08-06 00:00	00:54:17.64	-05:22:17.0	HIP 4308	13.88
2026-08-06 12:00	00:54:17.11	-05:23:17.0	HIP 4308	13.77
2026-08-07 00:00	00:54:16.30	-05:24:18.5	HIP 4308	13.80
2026-08-07 12:00	00:54:15.22	-05:25:21.5	HIP 4308	13.97
2026-08-08 00:00	00:54:13.85	-05:26:25.8	HIP 4308	14.29
2026-08-08 12:00	00:54:12.21	-05:27:31.5	HIP 4308	14.76
2026-08-09 00:00	00:54:10.29	-05:28:38.6	HIP 4308	15.38
2026-08-09 12:00	00:54:08.10	-05:29:47.1	HIP 4308	16.14
2026-08-10 00:00	00:54:05.62	-05:30:56.9	HIP 4156	16.05
2026-08-10 12:00	00:54:02.86	-05:32:08.1	HIP 4156	14.98
2026-08-11 00:00	00:53:59.83	-05:33:20.6	HIP 4156	13.89
2026-08-11 12:00	00:53:56.52	-05:34:34.4	HIP 4156	12.79
2026-08-12 00:00	00:53:52.93	-05:35:49.6	HIP 4156	11.71
2026-08-12 12:00	00:53:49.06	-05:37:06.0	HIP 4156	10.67
2026-08-13 00:00	00:53:44.91	-05:38:23.7	HIP 4156	9.71
2026-08-13 12:00	00:53:40.49	-05:39:42.7	HIP 4156	8.90
2026-08-14 00:00	00:53:35.79	-05:41:02.9	HIP 4156	8.32
2026-08-14 12:00	00:53:30.82	-05:42:24.3	HIP 4156	8.05
2026-08-15 00:00	00:53:25.57	-05:43:46.9	HIP 4156	8.17
2026-08-15 12:00	00:53:20.05	-05:45:10.8	HIP 4156	8.70
2026-08-16 00:00	00:53:14.25	-05:46:35.8	HIP 4156	9.62
2026-08-16 12:00	00:53:08.18	-05:48:01.9	HIP 4156	10.85
2026-08-17 00:00	00:53:01.84	-05:49:29.2	HIP 4156	12.34
2026-08-17 12:00	00:52:55.23	-05:50:57.6	HIP 4156	14.04
2026-08-18 00:00	00:52:48.35	-05:52:27.1	HIP 4068	11.90
2026-08-18 12:00	00:52:41.20	-05:53:57.6	HIP 4068	9.57
2026-08-19 00:00	00:52:33.79	-05:55:29.2	HIP 4068	7.18