메타데이터
| 항목 |
값 |
| Designation |
C/2020 X4 (Leonard) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-11-14T11:24:14.964480Z |
| Orbit solution date (soln_date, UTC) |
2021-09-20T00:12:50Z |
| Obs used |
113 |
| NEO |
- |
| M1 |
7.200 |
| K1 |
13.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-12-14T02:02:54.758400Z |
| Discovery magnitude (MPC) |
20.00 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2021-02-28.0000000 |
| e |
0.87940102 |
| q (au) |
5.205810 |
| a (au) |
43.166284 |
| i (deg) |
80.491366 |
| Ω (om, deg) |
161.905337 |
| ω (w, deg) |
139.911326 |
| M (ma, deg) |
0.366726 |
밝기
산란 + 전체 선형
$$
M_a = (4.783 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
4.783 |
| n |
6.000 |
| gf |
0.999 |
| 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
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
03:30:06.10 |
-54:49:00.6 |
HIP 16320 |
2.30 |
| 2026-07-29 12:00 |
03:30:13.98 |
-54:51:05.2 |
HIP 16320 |
2.82 |
| 2026-07-30 00:00 |
03:30:21.75 |
-54:53:10.3 |
HIP 16320 |
4.67 |
| 2026-07-30 12:00 |
03:30:29.42 |
-54:55:15.6 |
HIP 16320 |
6.86 |
| 2026-07-31 00:00 |
03:30:36.98 |
-54:57:21.4 |
HIP 16320 |
9.13 |
| 2026-07-31 12:00 |
03:30:44.44 |
-54:59:27.6 |
HIP 16320 |
11.44 |
| 2026-08-01 00:00 |
03:30:51.80 |
-55:01:34.1 |
HIP 16320 |
13.77 |
| 2026-08-01 12:00 |
03:30:59.04 |
-55:03:40.9 |
HIP 16409 |
11.56 |
| 2026-08-02 00:00 |
03:31:06.19 |
-55:05:48.1 |
HIP 16409 |
9.28 |
| 2026-08-02 12:00 |
03:31:13.22 |
-55:07:55.7 |
HIP 16409 |
7.05 |
| 2026-08-03 00:00 |
03:31:20.15 |
-55:10:03.6 |
HIP 16409 |
4.92 |
| 2026-08-03 12:00 |
03:31:26.96 |
-55:12:11.8 |
HIP 16409 |
3.10 |
| 2026-08-04 00:00 |
03:31:33.67 |
-55:14:20.3 |
HIP 16409 |
2.46 |
| 2026-08-04 12:00 |
03:31:40.27 |
-55:16:29.2 |
HIP 16409 |
3.65 |
| 2026-08-05 00:00 |
03:31:46.76 |
-55:18:38.4 |
HIP 16409 |
5.62 |
| 2026-08-05 12:00 |
03:31:53.14 |
-55:20:47.8 |
HIP 16409 |
7.78 |
| 2026-08-06 00:00 |
03:31:59.41 |
-55:22:57.6 |
HIP 16409 |
10.02 |
| 2026-08-06 12:00 |
03:32:05.56 |
-55:25:07.6 |
HIP 16409 |
12.29 |
| 2026-08-07 00:00 |
03:32:11.61 |
-55:27:18.0 |
HIP 16409 |
14.58 |
| 2026-08-07 12:00 |
03:32:17.54 |
-55:29:28.6 |
HIP 16409 |
16.88 |
| 2026-08-08 00:00 |
03:32:23.35 |
-55:31:39.4 |
HIP 16409 |
19.18 |
| 2026-08-08 12:00 |
03:32:29.05 |
-55:33:50.5 |
HIP 16409 |
21.48 |
| 2026-08-09 00:00 |
03:32:34.64 |
-55:36:01.9 |
HIP 16409 |
23.78 |
| 2026-08-09 12:00 |
03:32:40.11 |
-55:38:13.5 |
HIP 16409 |
26.08 |
| 2026-08-10 00:00 |
03:32:45.46 |
-55:40:25.3 |
HIP 16284 |
27.54 |
| 2026-08-10 12:00 |
03:32:50.70 |
-55:42:37.3 |
HIP 16284 |
27.17 |
| 2026-08-11 00:00 |
03:32:55.82 |
-55:44:49.6 |
HIP 16284 |
26.99 |
| 2026-08-11 12:00 |
03:33:00.82 |
-55:47:02.0 |
HIP 16284 |
26.99 |
| 2026-08-12 00:00 |
03:33:05.70 |
-55:49:14.7 |
HIP 16284 |
27.16 |
| 2026-08-12 12:00 |
03:33:10.47 |
-55:51:27.5 |
HIP 16284 |
27.52 |
| 2026-08-13 00:00 |
03:33:15.11 |
-55:53:40.5 |
HIP 16284 |
28.04 |
| 2026-08-13 12:00 |
03:33:19.64 |
-55:55:53.7 |
HIP 16284 |
28.72 |
| 2026-08-14 00:00 |
03:33:24.04 |
-55:58:07.0 |
HIP 16284 |
29.54 |
| 2026-08-14 12:00 |
03:33:28.33 |
-56:00:20.5 |
HIP 16284 |
30.51 |
| 2026-08-15 00:00 |
03:33:32.49 |
-56:02:34.1 |
HIP 16284 |
31.59 |
| 2026-08-15 12:00 |
03:33:36.53 |
-56:04:47.8 |
HIP 16284 |
32.79 |
| 2026-08-16 00:00 |
03:33:40.45 |
-56:07:01.6 |
HIP 16284 |
34.08 |
| 2026-08-16 12:00 |
03:33:44.24 |
-56:09:15.6 |
HIP 16284 |
35.45 |
| 2026-08-17 00:00 |
03:33:47.91 |
-56:11:29.6 |
HIP 16284 |
36.91 |
| 2026-08-17 12:00 |
03:33:51.46 |
-56:13:43.8 |
HIP 16284 |
38.43 |
| 2026-08-18 00:00 |
03:33:54.89 |
-56:15:58.0 |
HIP 16990 |
39.19 |
| 2026-08-18 12:00 |
03:33:58.19 |
-56:18:12.3 |
HIP 16990 |
39.21 |
| 2026-08-19 00:00 |
03:34:01.37 |
-56:20:26.6 |
HIP 16990 |
39.38 |