메타데이터

항목	값
Designation	50P/Arend
Type	P
Perihelion (tp_cal, UTC)	2007-11-02T19:43:29.481600Z
Orbit solution date (soln_date, UTC)	2025-10-01T16:07:23Z
Obs used	1874
NEO	-
M1	13.900
K1	9.000
PC	-

Osculating 궤도요소

항목	값
Epoch (epoch_cal, TDB)	2011-07-01.0000000
e	0.53063813
q (au)	1.918329
a (au)	4.087100
i (deg)	19.155639
Ω (om, deg)	355.310553
ω (w, deg)	49.039728
M (ma, deg)	159.384273

밝기

산란 + 전체 선형

$$ M_a = (12.457 + 4.038\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목	값
H0	12.457
n	4.038
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
2023-08-17	2024-05-13	+13.6006	-5.552
2024-05-13	2025-05-02	-14.3888	+6.578

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

천체력

Date/Time (UTC)	RA (J2000)	Dec (J2000)	Nearest HIP	Dist from HIP (arcmin)
2026-07-29 00:00	11:54:12.75	-04:14:51.4	HIP 58042	7.34
2026-07-29 12:00	11:54:29.53	-04:16:56.2	HIP 58042	6.67
2026-07-30 00:00	11:54:46.38	-04:19:01.7	HIP 58042	8.89
2026-07-30 12:00	11:55:03.31	-04:21:07.6	HIP 58042	12.57
2026-07-31 00:00	11:55:20.32	-04:23:14.2	HIP 58042	16.79
2026-07-31 12:00	11:55:37.40	-04:25:21.3	HIP 58197	17.59
2026-08-01 00:00	11:55:54.56	-04:27:28.9	HIP 58197	18.27
2026-08-01 12:00	11:56:11.80	-04:29:37.1	HIP 58197	20.10
2026-08-02 00:00	11:56:29.11	-04:31:45.8	HIP 58268	17.08
2026-08-02 12:00	11:56:46.50	-04:33:55.1	HIP 58268	13.50
2026-08-03 00:00	11:57:03.96	-04:36:04.9	HIP 58268	10.92
2026-08-03 12:00	11:57:21.49	-04:38:15.2	HIP 58268	10.18
2026-08-04 00:00	11:57:39.10	-04:40:26.0	HIP 58268	11.65
2026-08-04 12:00	11:57:56.78	-04:42:37.4	HIP 58268	14.71
2026-08-05 00:00	11:58:14.53	-04:44:49.3	HIP 58443	12.21
2026-08-05 12:00	11:58:32.35	-04:47:01.7	HIP 58443	7.65
2026-08-06 00:00	11:58:50.23	-04:49:14.7	HIP 58443	4.12
2026-08-06 12:00	11:59:08.19	-04:51:28.1	HIP 58443	5.01
2026-08-07 00:00	11:59:26.22	-04:53:42.0	HIP 58443	9.14
2026-08-07 12:00	11:59:44.32	-04:55:56.5	HIP 58443	13.88
2026-08-08 00:00	12:00:02.48	-04:58:11.5	HIP 58569	12.69
2026-08-08 12:00	12:00:20.71	-05:00:26.9	HIP 58569	8.07
2026-08-09 00:00	12:00:39.00	-05:02:42.9	HIP 58569	4.53
2026-08-09 12:00	12:00:57.36	-05:04:59.3	HIP 58569	5.27
2026-08-10 00:00	12:01:15.79	-05:07:16.2	HIP 58569	9.35
2026-08-10 12:00	12:01:34.28	-05:09:33.6	HIP 58569	14.15
2026-08-11 00:00	12:01:52.83	-05:11:51.5	HIP 58569	19.14
2026-08-11 12:00	12:02:11.45	-05:14:09.9	HIP 58569	24.22
2026-08-12 00:00	12:02:30.13	-05:16:28.7	HIP 58797	20.40
2026-08-12 12:00	12:02:48.86	-05:18:48.0	HIP 58797	15.31
2026-08-13 00:00	12:03:07.66	-05:21:07.7	HIP 58797	10.32
2026-08-13 12:00	12:03:26.52	-05:23:27.9	HIP 58797	5.76
2026-08-14 00:00	12:03:45.44	-05:25:48.6	HIP 58797	3.86
2026-08-14 12:00	12:04:04.42	-05:28:09.7	HIP 58797	7.21
2026-08-15 00:00	12:04:23.45	-05:30:31.2	HIP 58797	12.05
2026-08-15 12:00	12:04:42.54	-05:32:53.2	HIP 58872	12.74
2026-08-16 00:00	12:05:01.68	-05:35:15.6	HIP 58872	13.10
2026-08-16 12:00	12:05:20.89	-05:37:38.4	HIP 58981	13.58
2026-08-17 00:00	12:05:40.14	-05:40:01.7	HIP 58981	10.80
2026-08-17 12:00	12:05:59.45	-05:42:25.4	HIP 58981	10.31
2026-08-18 00:00	12:06:18.81	-05:44:49.5	HIP 58981	12.39
2026-08-18 12:00	12:06:38.22	-05:47:14.0	HIP 59109	9.76
2026-08-19 00:00	12:06:57.69	-05:49:38.9	HIP 59109	7.14