메타데이터

항목	값
Designation	177P/Barnard
Type	P
Perihelion (tp_cal, UTC)	2006-08-28T16:23:52.091520Z
Orbit solution date (soln_date, UTC)	2021-04-15T23:27:46Z
Obs used	1702
NEO	Yes
M1	15.700
K1	13.000
PC	0.030

Osculating 궤도요소

항목	값
Epoch (epoch_cal, TDB)	2006-04-24.0000000
e	0.95444204
q (au)	1.107271
a (au)	24.304669
i (deg)	31.216459
Ω (om, deg)	272.067721
ω (w, deg)	60.453551
M (ma, deg)	358.957950

밝기

산란 + 전체 선형

$$ M_a = (15.195 + 4.041\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

모델 상수

항목	값
H0	15.195
n	4.041
gf	1.000
gb	-0.500
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
2006-06-23	2006-08-28	+13.5160	-2.197
2006-08-28	2006-11-01	-5.2733	-2.545
2006-11-01	2006-12-11	+35.3909	-8.724

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

천체력

Date/Time (UTC)	RA (J2000)	Dec (J2000)	Nearest HIP	Dist from HIP (arcmin)
2026-06-01 00:00	08:41:20.23	-05:01:20.4	HIP 42634	12.82
2026-06-01 12:00	08:41:22.19	-05:01:10.8	HIP 42634	12.68
2026-06-02 00:00	08:41:24.17	-05:01:01.5	HIP 42634	12.57
2026-06-02 12:00	08:41:26.18	-05:00:52.3	HIP 42634	12.49
2026-06-03 00:00	08:41:28.21	-05:00:43.3	HIP 42634	12.43
2026-06-03 12:00	08:41:30.26	-05:00:34.5	HIP 42634	12.39
2026-06-04 00:00	08:41:32.34	-05:00:25.9	HIP 42634	12.39
2026-06-04 12:00	08:41:34.44	-05:00:17.5	HIP 42634	12.41
2026-06-05 00:00	08:41:36.56	-05:00:09.2	HIP 42634	12.46
2026-06-05 12:00	08:41:38.71	-05:00:01.2	HIP 42634	12.54
2026-06-06 00:00	08:41:40.88	-04:59:53.4	HIP 42634	12.65
2026-06-06 12:00	08:41:43.06	-04:59:45.7	HIP 42634	12.79
2026-06-07 00:00	08:41:45.28	-04:59:38.3	HIP 42634	12.95
2026-06-07 12:00	08:41:47.51	-04:59:31.0	HIP 42634	13.15
2026-06-08 00:00	08:41:49.76	-04:59:24.0	HIP 42634	13.37
2026-06-08 12:00	08:41:52.04	-04:59:17.1	HIP 42634	13.61
2026-06-09 00:00	08:41:54.34	-04:59:10.4	HIP 42634	13.89
2026-06-09 12:00	08:41:56.66	-04:59:04.0	HIP 42634	14.18
2026-06-10 00:00	08:41:59.00	-04:58:57.7	HIP 42634	14.51
2026-06-10 12:00	08:42:01.36	-04:58:51.6	HIP 42634	14.85
2026-06-11 00:00	08:42:03.74	-04:58:45.7	HIP 42634	15.22
2026-06-11 12:00	08:42:06.15	-04:58:40.1	HIP 42634	15.60
2026-06-12 00:00	08:42:08.57	-04:58:34.6	HIP 42634	16.01
2026-06-12 12:00	08:42:11.01	-04:58:29.3	HIP 42634	16.43
2026-06-13 00:00	08:42:13.48	-04:58:24.2	HIP 42634	16.88
2026-06-13 12:00	08:42:15.96	-04:58:19.4	HIP 42634	17.34
2026-06-14 00:00	08:42:18.47	-04:58:14.7	HIP 42634	17.81
2026-06-14 12:00	08:42:20.99	-04:58:10.2	HIP 42634	18.30
2026-06-15 00:00	08:42:23.53	-04:58:06.0	HIP 42634	18.81
2026-06-15 12:00	08:42:26.09	-04:58:01.9	HIP 42634	19.33
2026-06-16 00:00	08:42:28.68	-04:57:58.0	HIP 42634	19.86
2026-06-16 12:00	08:42:31.28	-04:57:54.4	HIP 42634	20.40
2026-06-17 00:00	08:42:33.90	-04:57:50.9	HIP 42759	20.78
2026-06-17 12:00	08:42:36.53	-04:57:47.7	HIP 42759	20.62
2026-06-18 00:00	08:42:39.19	-04:57:44.6	HIP 42759	20.48
2026-06-18 12:00	08:42:41.86	-04:57:41.8	HIP 42759	20.36
2026-06-19 00:00	08:42:44.55	-04:57:39.1	HIP 42759	20.27
2026-06-19 12:00	08:42:47.26	-04:57:36.7	HIP 42759	20.20
2026-06-20 00:00	08:42:49.99	-04:57:34.5	HIP 42759	20.16
2026-06-20 12:00	08:42:52.73	-04:57:32.4	HIP 42759	20.15
2026-06-21 00:00	08:42:55.50	-04:57:30.6	HIP 42759	20.16
2026-06-21 12:00	08:42:58.27	-04:57:29.0	HIP 42759	20.20
2026-06-22 00:00	08:43:01.07	-04:57:27.6	HIP 42759	20.26