메타데이터
| 항목 |
값 |
| Designation |
C/1885 X2 (Barnard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1886-05-03T18:53:20.048640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:53Z |
| Obs used |
76 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
1886-02-01.0000000 |
| e |
1.00020016 |
| q (au) |
0.479255 |
| a (au) |
-2394.381815 |
| i (deg) |
84.440812 |
| Ω (om, deg) |
69.909995 |
| ω (w, deg) |
119.624515 |
| M (ma, deg) |
-0.000772 |
밝기
산란 + 전체 선형
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
04:47:38.43 |
-44:28:31.8 |
HIP 22268 |
12.42 |
| 2026-05-12 12:00 |
04:47:39.42 |
-44:28:27.0 |
HIP 22268 |
12.34 |
| 2026-05-13 00:00 |
04:47:40.41 |
-44:28:22.4 |
HIP 22268 |
12.26 |
| 2026-05-13 12:00 |
04:47:41.41 |
-44:28:17.8 |
HIP 22268 |
12.19 |
| 2026-05-14 00:00 |
04:47:42.41 |
-44:28:13.3 |
HIP 22268 |
12.12 |
| 2026-05-14 12:00 |
04:47:43.41 |
-44:28:08.9 |
HIP 22268 |
12.05 |
| 2026-05-15 00:00 |
04:47:44.42 |
-44:28:04.6 |
HIP 22268 |
11.99 |
| 2026-05-15 12:00 |
04:47:45.42 |
-44:28:00.4 |
HIP 22268 |
11.94 |
| 2026-05-16 00:00 |
04:47:46.44 |
-44:27:56.2 |
HIP 22268 |
11.88 |
| 2026-05-16 12:00 |
04:47:47.45 |
-44:27:52.2 |
HIP 22268 |
11.83 |
| 2026-05-17 00:00 |
04:47:48.47 |
-44:27:48.2 |
HIP 22268 |
11.79 |
| 2026-05-17 12:00 |
04:47:49.49 |
-44:27:44.3 |
HIP 22268 |
11.75 |
| 2026-05-18 00:00 |
04:47:50.51 |
-44:27:40.5 |
HIP 22268 |
11.72 |
| 2026-05-18 12:00 |
04:47:51.53 |
-44:27:36.8 |
HIP 22268 |
11.68 |
| 2026-05-19 00:00 |
04:47:52.56 |
-44:27:33.1 |
HIP 22268 |
11.66 |
| 2026-05-19 12:00 |
04:47:53.59 |
-44:27:29.6 |
HIP 22268 |
11.64 |
| 2026-05-20 00:00 |
04:47:54.62 |
-44:27:26.1 |
HIP 22268 |
11.62 |
| 2026-05-20 12:00 |
04:47:55.66 |
-44:27:22.7 |
HIP 22268 |
11.61 |
| 2026-05-21 00:00 |
04:47:56.70 |
-44:27:19.4 |
HIP 22268 |
11.60 |
| 2026-05-21 12:00 |
04:47:57.73 |
-44:27:16.2 |
HIP 22268 |
11.60 |
| 2026-05-22 00:00 |
04:47:58.78 |
-44:27:13.1 |
HIP 22268 |
11.60 |
| 2026-05-22 12:00 |
04:47:59.82 |
-44:27:10.0 |
HIP 22268 |
11.61 |
| 2026-05-23 00:00 |
04:48:00.86 |
-44:27:07.1 |
HIP 22268 |
11.62 |
| 2026-05-23 12:00 |
04:48:01.91 |
-44:27:04.2 |
HIP 22268 |
11.64 |
| 2026-05-24 00:00 |
04:48:02.96 |
-44:27:01.4 |
HIP 22268 |
11.66 |
| 2026-05-24 12:00 |
04:48:04.01 |
-44:26:58.8 |
HIP 22268 |
11.68 |
| 2026-05-25 00:00 |
04:48:05.06 |
-44:26:56.2 |
HIP 22268 |
11.71 |
| 2026-05-25 12:00 |
04:48:06.11 |
-44:26:53.6 |
HIP 22268 |
11.75 |
| 2026-05-26 00:00 |
04:48:07.16 |
-44:26:51.2 |
HIP 22268 |
11.79 |
| 2026-05-26 12:00 |
04:48:08.22 |
-44:26:48.9 |
HIP 22268 |
11.83 |
| 2026-05-27 00:00 |
04:48:09.28 |
-44:26:46.6 |
HIP 22268 |
11.88 |
| 2026-05-27 12:00 |
04:48:10.33 |
-44:26:44.5 |
HIP 22268 |
11.93 |
| 2026-05-28 00:00 |
04:48:11.39 |
-44:26:42.4 |
HIP 22268 |
11.99 |
| 2026-05-28 12:00 |
04:48:12.45 |
-44:26:40.4 |
HIP 22268 |
12.05 |
| 2026-05-29 00:00 |
04:48:13.52 |
-44:26:38.5 |
HIP 22268 |
12.11 |
| 2026-05-29 12:00 |
04:48:14.58 |
-44:26:36.7 |
HIP 22268 |
12.18 |
| 2026-05-30 00:00 |
04:48:15.64 |
-44:26:35.0 |
HIP 22268 |
12.25 |
| 2026-05-30 12:00 |
04:48:16.70 |
-44:26:33.3 |
HIP 22268 |
12.33 |
| 2026-05-31 00:00 |
04:48:17.77 |
-44:26:31.8 |
HIP 22268 |
12.41 |
| 2026-05-31 12:00 |
04:48:18.83 |
-44:26:30.3 |
HIP 22268 |
12.50 |
| 2026-06-01 00:00 |
04:48:19.90 |
-44:26:28.9 |
HIP 22268 |
12.58 |
| 2026-06-01 12:00 |
04:48:20.97 |
-44:26:27.7 |
HIP 22268 |
12.68 |
| 2026-06-02 00:00 |
04:48:22.03 |
-44:26:26.5 |
HIP 22268 |
12.77 |