메타데이터

항목	값
Designation	249P/LINEAR
Type	P
Perihelion (tp_cal, UTC)	2015-11-26T18:53:49.649280Z
Orbit solution date (soln_date, UTC)	2023-01-03T10:14:16Z
Obs used	884
NEO	Yes
M1	18.400
K1	4.500
PC	-

Osculating 궤도요소

항목	값
Epoch (epoch_cal, TDB)	2014-07-25.0000000
e	0.81866843
q (au)	0.502345
a (au)	2.770312
i (deg)	8.399344
Ω (om, deg)	239.852044
ω (w, deg)	64.810358
M (ma, deg)	255.306758

밝기

산란 + 전체 선형

$$ M_a = (19.108 + 2.351\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목	값
H0	19.108
n	2.351
gf	1.000
gb	-0.644
k	0.800
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
2020-01-25	2020-06-02	+14.5622	-0.412
2020-06-02	2020-08-01	+43.3682	+3.425
2020-08-01	2021-01-18	-1.3785	+0.228

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

찾아보기

천체력

Date/Time (UTC)	RA (J2000)	Dec (J2000)	Nearest HIP	Dist from HIP (arcmin)
2026-09-20 00:00	08:22:14.70	+13:02:18.7	HIP 40956	17.37
2026-09-20 12:00	08:22:31.40	+13:00:45.8	HIP 40956	19.18
2026-09-21 00:00	08:22:47.98	+12:59:12.9	HIP 40956	21.70
2026-09-21 12:00	08:23:04.44	+12:57:40.2	HIP 40956	24.69
2026-09-22 00:00	08:23:20.78	+12:56:07.5	HIP 40956	28.00
2026-09-22 12:00	08:23:36.99	+12:54:35.0	HIP 40956	31.51
2026-09-23 00:00	08:23:53.07	+12:53:02.6	HIP 40956	35.16
2026-09-23 12:00	08:24:09.03	+12:51:30.3	HIP 40956	38.89
2026-09-24 00:00	08:24:24.86	+12:49:58.1	HIP 41400	35.56
2026-09-24 12:00	08:24:40.56	+12:48:26.0	HIP 41400	31.45
2026-09-25 00:00	08:24:56.13	+12:46:54.1	HIP 41400	27.37
2026-09-25 12:00	08:25:11.57	+12:45:22.3	HIP 41400	23.33
2026-09-26 00:00	08:25:26.88	+12:43:50.6	HIP 41400	19.34
2026-09-26 12:00	08:25:42.06	+12:42:19.1	HIP 41400	15.39
2026-09-27 00:00	08:25:57.11	+12:40:47.8	HIP 41400	11.52
2026-09-27 12:00	08:26:12.03	+12:39:16.6	HIP 41400	7.79
2026-09-28 00:00	08:26:26.81	+12:37:45.6	HIP 41400	4.45
2026-09-28 12:00	08:26:41.45	+12:36:14.7	HIP 41400	3.11
2026-09-29 00:00	08:26:55.96	+12:34:44.0	HIP 41400	5.42
2026-09-29 12:00	08:27:10.33	+12:33:13.5	HIP 41400	8.85
2026-09-30 00:00	08:27:24.57	+12:31:43.2	HIP 41400	12.47
2026-09-30 12:00	08:27:38.66	+12:30:13.0	HIP 41400	16.14
2026-10-01 00:00	08:27:52.62	+12:28:43.1	HIP 41474	18.55
2026-10-01 12:00	08:28:06.43	+12:27:13.3	HIP 41623	16.40
2026-10-02 00:00	08:28:20.10	+12:25:43.8	HIP 41623	14.07
2026-10-02 12:00	08:28:33.63	+12:24:14.5	HIP 41623	12.41
2026-10-03 00:00	08:28:47.02	+12:22:45.4	HIP 41623	11.69
2026-10-03 12:00	08:29:00.26	+12:21:16.5	HIP 41623	12.04
2026-10-04 00:00	08:29:13.35	+12:19:47.8	HIP 41623	13.36
2026-10-04 12:00	08:29:26.30	+12:18:19.4	HIP 41623	15.38
2026-10-05 00:00	08:29:39.09	+12:16:51.3	HIP 41623	17.83
2026-10-05 12:00	08:29:51.74	+12:15:23.4	HIP 41623	20.56
2026-10-06 00:00	08:30:04.24	+12:13:55.7	HIP 41623	23.44
2026-10-06 12:00	08:30:16.58	+12:12:28.3	HIP 41790	25.55
2026-10-07 00:00	08:30:28.77	+12:11:01.2	HIP 41790	22.73
2026-10-07 12:00	08:30:40.81	+12:09:34.4	HIP 41790	20.10
2026-10-08 00:00	08:30:52.69	+12:08:07.9	HIP 41790	17.69
2026-10-08 12:00	08:31:04.41	+12:06:41.6	HIP 41790	15.60
2026-10-09 00:00	08:31:15.98	+12:05:15.7	HIP 41790	13.95
2026-10-09 12:00	08:31:27.39	+12:03:50.1	HIP 41790	12.88
2026-10-10 00:00	08:31:38.64	+12:02:24.8	HIP 41790	12.51
2026-10-10 12:00	08:31:49.73	+12:00:59.8	HIP 41790	12.87
2026-10-11 00:00	08:32:00.65	+11:59:35.1	HIP 41790	13.88