메타데이터
| 항목 |
값 |
| Designation |
P/2020 B4 (Sheppard) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-11-25T07:31:50.350080Z |
| Orbit solution date (soln_date, UTC) |
2023-05-18T19:13:12Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
7.600 |
| K1 |
13.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-01-26T04:22:00.480000Z |
| Discovery magnitude (MPC) |
22.50 r |
| Discovery observatory (MPC) |
807 · Cerro Tololo Observatory, La Serena |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2020-06-04.0000000 |
| e |
0.19253094 |
| q (au) |
6.438946 |
| a (au) |
7.974232 |
| i (deg) |
11.601007 |
| Ω (om, deg) |
186.003502 |
| ω (w, deg) |
342.456738 |
| M (ma, deg) |
336.394550 |
밝기
산란 + 전체 선형
$$
M_a = (6.183 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
6.183 |
| n |
6.000 |
| gf |
0.935 |
| gb |
-0.981 |
| k |
1.000 |
| δ90 |
7.598 |
| 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) |
| 2026-07-29 00:00 |
17:18:21.48 |
-10:29:42.2 |
HIP 84678 |
17.19 |
| 2026-07-29 12:00 |
17:18:15.96 |
-10:30:10.1 |
HIP 84678 |
18.04 |
| 2026-07-30 00:00 |
17:18:10.54 |
-10:30:38.4 |
HIP 84678 |
18.96 |
| 2026-07-30 12:00 |
17:18:05.24 |
-10:31:07.0 |
HIP 84678 |
19.93 |
| 2026-07-31 00:00 |
17:18:00.05 |
-10:31:36.0 |
HIP 84678 |
20.95 |
| 2026-07-31 12:00 |
17:17:54.96 |
-10:32:05.3 |
HIP 84678 |
21.99 |
| 2026-08-01 00:00 |
17:17:49.99 |
-10:32:34.9 |
HIP 84678 |
23.05 |
| 2026-08-01 12:00 |
17:17:45.13 |
-10:33:05.0 |
HIP 84539 |
23.83 |
| 2026-08-02 00:00 |
17:17:40.38 |
-10:33:35.3 |
HIP 84539 |
22.84 |
| 2026-08-02 12:00 |
17:17:35.74 |
-10:34:06.0 |
HIP 84539 |
21.88 |
| 2026-08-03 00:00 |
17:17:31.22 |
-10:34:37.1 |
HIP 84539 |
20.96 |
| 2026-08-03 12:00 |
17:17:26.81 |
-10:35:08.4 |
HIP 84539 |
20.07 |
| 2026-08-04 00:00 |
17:17:22.52 |
-10:35:40.2 |
HIP 84539 |
19.22 |
| 2026-08-04 12:00 |
17:17:18.34 |
-10:36:12.2 |
HIP 84539 |
18.41 |
| 2026-08-05 00:00 |
17:17:14.27 |
-10:36:44.6 |
HIP 84539 |
17.64 |
| 2026-08-05 12:00 |
17:17:10.32 |
-10:37:17.2 |
HIP 84539 |
16.91 |
| 2026-08-06 00:00 |
17:17:06.49 |
-10:37:50.2 |
HIP 84539 |
16.23 |
| 2026-08-06 12:00 |
17:17:02.78 |
-10:38:23.6 |
HIP 84539 |
15.58 |
| 2026-08-07 00:00 |
17:16:59.18 |
-10:38:57.2 |
HIP 84539 |
14.98 |
| 2026-08-07 12:00 |
17:16:55.70 |
-10:39:31.2 |
HIP 84539 |
14.43 |
| 2026-08-08 00:00 |
17:16:52.34 |
-10:40:05.4 |
HIP 84539 |
13.92 |
| 2026-08-08 12:00 |
17:16:49.09 |
-10:40:40.0 |
HIP 84539 |
13.45 |
| 2026-08-09 00:00 |
17:16:45.97 |
-10:41:14.9 |
HIP 84539 |
13.03 |
| 2026-08-09 12:00 |
17:16:42.97 |
-10:41:50.0 |
HIP 84539 |
12.66 |
| 2026-08-10 00:00 |
17:16:40.09 |
-10:42:25.5 |
HIP 84539 |
12.33 |
| 2026-08-10 12:00 |
17:16:37.32 |
-10:43:01.2 |
HIP 84539 |
12.05 |
| 2026-08-11 00:00 |
17:16:34.68 |
-10:43:37.3 |
HIP 84476 |
11.60 |
| 2026-08-11 12:00 |
17:16:32.16 |
-10:44:13.6 |
HIP 84476 |
10.77 |
| 2026-08-12 00:00 |
17:16:29.77 |
-10:44:50.2 |
HIP 84476 |
9.95 |
| 2026-08-12 12:00 |
17:16:27.49 |
-10:45:27.1 |
HIP 84476 |
9.15 |
| 2026-08-13 00:00 |
17:16:25.34 |
-10:46:04.2 |
HIP 84476 |
8.36 |
| 2026-08-13 12:00 |
17:16:23.31 |
-10:46:41.7 |
HIP 84476 |
7.59 |
| 2026-08-14 00:00 |
17:16:21.41 |
-10:47:19.3 |
HIP 84476 |
6.83 |
| 2026-08-14 12:00 |
17:16:19.62 |
-10:47:57.3 |
HIP 84476 |
6.08 |
| 2026-08-15 00:00 |
17:16:17.97 |
-10:48:35.5 |
HIP 84476 |
5.34 |
| 2026-08-15 12:00 |
17:16:16.43 |
-10:49:13.9 |
HIP 84476 |
4.62 |
| 2026-08-16 00:00 |
17:16:15.02 |
-10:49:52.6 |
HIP 84476 |
3.90 |
| 2026-08-16 12:00 |
17:16:13.74 |
-10:50:31.6 |
HIP 84476 |
3.20 |
| 2026-08-17 00:00 |
17:16:12.58 |
-10:51:10.8 |
HIP 84476 |
2.50 |
| 2026-08-17 12:00 |
17:16:11.54 |
-10:51:50.2 |
HIP 84476 |
1.82 |
| 2026-08-18 00:00 |
17:16:10.63 |
-10:52:29.8 |
HIP 84476 |
1.15 |
| 2026-08-18 12:00 |
17:16:09.84 |
-10:53:09.7 |
HIP 84476 |
0.56 |
| 2026-08-19 00:00 |
17:16:09.18 |
-10:53:49.8 |
HIP 84476 |
0.47 |