메타데이터

항목	값
Designation	8P/Tuttle
Type	P
Perihelion (tp_cal, UTC)	2008-01-27T00:25:56.539200Z
Orbit solution date (soln_date, UTC)	2022-05-02T08:47:13Z
Obs used	1768
NEO	Yes
M1	14.600
K1	4.500
PC	-

Osculating 궤도요소

항목	값
Epoch (epoch_cal, TDB)	2008-08-23.0000000
e	0.81978762
q (au)	1.027263
a (au)	5.700291
i (deg)	54.981969
Ω (om, deg)	270.342162
ω (w, deg)	207.511518
M (ma, deg)	15.134474

밝기

산란 + 전체 선형

$$ M_a = (10.014 + 5.507\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목	값
H0	10.014
n	5.507
gf	0.998
gb	-1.000
k	0.996
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
2020-06-21	2021-10-15	-14.7328	-0.879
2021-10-15	2021-08-27	+8.0581	-2.802
2021-08-27	2022-03-19	-2.3685	+0.975

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

천체력

Date/Time (UTC)	RA (J2000)	Dec (J2000)	Nearest HIP	Dist from HIP (arcmin)
2026-05-12 00:00	18:59:55.21	-07:30:17.6	HIP 93324	11.15
2026-05-12 12:00	18:59:48.35	-07:29:25.5	HIP 93324	12.03
2026-05-13 00:00	18:59:41.40	-07:28:33.6	HIP 93324	13.15
2026-05-13 12:00	18:59:34.35	-07:27:42.1	HIP 93189	12.42
2026-05-14 00:00	18:59:27.21	-07:26:50.9	HIP 93189	10.48
2026-05-14 12:00	18:59:19.97	-07:26:00.1	HIP 93189	8.54
2026-05-15 00:00	18:59:12.63	-07:25:09.6	HIP 93189	6.61
2026-05-15 12:00	18:59:05.21	-07:24:19.4	HIP 93189	4.73
2026-05-16 00:00	18:58:57.69	-07:23:29.6	HIP 93189	3.04
2026-05-16 12:00	18:58:50.08	-07:22:40.1	HIP 93189	2.12
2026-05-17 00:00	18:58:42.38	-07:21:50.9	HIP 93189	2.89
2026-05-17 12:00	18:58:34.59	-07:21:02.1	HIP 93189	4.59
2026-05-18 00:00	18:58:26.70	-07:20:13.7	HIP 93189	6.55
2026-05-18 12:00	18:58:18.73	-07:19:25.6	HIP 93189	8.60
2026-05-19 00:00	18:58:10.67	-07:18:37.9	HIP 93189	10.71
2026-05-19 12:00	18:58:02.52	-07:17:50.5	HIP 93189	12.85
2026-05-20 00:00	18:57:54.29	-07:17:03.5	HIP 93189	15.01
2026-05-20 12:00	18:57:45.97	-07:16:16.9	HIP 93189	17.21
2026-05-21 00:00	18:57:37.56	-07:15:30.6	HIP 93189	19.42
2026-05-21 12:00	18:57:29.07	-07:14:44.7	HIP 93189	21.66
2026-05-22 00:00	18:57:20.49	-07:13:59.2	HIP 93189	23.91
2026-05-22 12:00	18:57:11.83	-07:13:14.0	HIP 93189	26.18
2026-05-23 00:00	18:57:03.09	-07:12:29.3	HIP 92868	28.25
2026-05-23 12:00	18:56:54.27	-07:11:44.9	HIP 92868	25.99
2026-05-24 00:00	18:56:45.36	-07:11:00.9	HIP 92868	23.73
2026-05-24 12:00	18:56:36.38	-07:10:17.3	HIP 92868	21.48
2026-05-25 00:00	18:56:27.31	-07:09:34.0	HIP 92868	19.23
2026-05-25 12:00	18:56:18.17	-07:08:51.2	HIP 92868	17.01
2026-05-26 00:00	18:56:08.95	-07:08:08.7	HIP 92868	14.82
2026-05-26 12:00	18:55:59.65	-07:07:26.7	HIP 92868	12.70
2026-05-27 00:00	18:55:50.28	-07:06:45.0	HIP 92868	10.70
2026-05-27 12:00	18:55:40.83	-07:06:03.7	HIP 92868	8.90
2026-05-28 00:00	18:55:31.30	-07:05:22.9	HIP 92868	7.49
2026-05-28 12:00	18:55:21.71	-07:04:42.4	HIP 92868	6.72
2026-05-29 00:00	18:55:12.03	-07:04:02.3	HIP 92868	6.84
2026-05-29 12:00	18:55:02.29	-07:03:22.7	HIP 92868	7.81
2026-05-30 00:00	18:54:52.48	-07:02:43.4	HIP 92868	9.39
2026-05-30 12:00	18:54:42.59	-07:02:04.6	HIP 92868	11.33
2026-05-31 00:00	18:54:32.64	-07:01:26.1	HIP 92868	13.49
2026-05-31 12:00	18:54:22.62	-07:00:48.1	HIP 92868	15.79
2026-06-01 00:00	18:54:12.53	-07:00:10.5	HIP 92868	18.17
2026-06-01 12:00	18:54:02.37	-06:59:33.3	HIP 92766	20.12
2026-06-02 00:00	18:53:52.14	-06:58:56.6	HIP 92766	21.20