메타데이터
| 항목 |
값 |
| Designation |
C/2018 EF9 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-05-23T03:04:52.170240Z |
| Orbit solution date (soln_date, UTC) |
2023-02-13T23:12:43Z |
| Obs used |
191 |
| NEO |
- |
| M1 |
8.600 |
| K1 |
45.250 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2018-04-18.0000000 |
| e |
0.99757417 |
| q (au) |
1.556633 |
| a (au) |
641.691299 |
| i (deg) |
84.694453 |
| Ω (om, deg) |
172.578066 |
| ω (w, deg) |
72.616575 |
| M (ma, deg) |
359.997870 |
밝기
산란 + 전체 선형
$$
M_a = (8.870 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
8.870 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.997 |
| 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) |
| 2026-09-20 00:00 |
01:13:48.66 |
-40:02:23.8 |
HIP 5897 |
22.97 |
| 2026-09-20 12:00 |
01:13:42.65 |
-40:03:12.3 |
HIP 5897 |
24.28 |
| 2026-09-21 00:00 |
01:13:36.62 |
-40:04:00.3 |
HIP 5897 |
25.60 |
| 2026-09-21 12:00 |
01:13:30.56 |
-40:04:47.8 |
HIP 5897 |
26.93 |
| 2026-09-22 00:00 |
01:13:24.48 |
-40:05:34.9 |
HIP 5897 |
28.27 |
| 2026-09-22 12:00 |
01:13:18.38 |
-40:06:21.5 |
HIP 5897 |
29.61 |
| 2026-09-23 00:00 |
01:13:12.26 |
-40:07:07.6 |
HIP 5686 |
29.58 |
| 2026-09-23 12:00 |
01:13:06.12 |
-40:07:53.3 |
HIP 5686 |
28.82 |
| 2026-09-24 00:00 |
01:12:59.96 |
-40:08:38.4 |
HIP 5686 |
28.12 |
| 2026-09-24 12:00 |
01:12:53.78 |
-40:09:23.1 |
HIP 5686 |
27.47 |
| 2026-09-25 00:00 |
01:12:47.58 |
-40:10:07.3 |
HIP 5686 |
26.89 |
| 2026-09-25 12:00 |
01:12:41.36 |
-40:10:51.1 |
HIP 5686 |
26.39 |
| 2026-09-26 00:00 |
01:12:35.12 |
-40:11:34.3 |
HIP 5686 |
25.95 |
| 2026-09-26 12:00 |
01:12:28.87 |
-40:12:17.0 |
HIP 5686 |
25.59 |
| 2026-09-27 00:00 |
01:12:22.60 |
-40:12:59.3 |
HIP 5686 |
25.31 |
| 2026-09-27 12:00 |
01:12:16.31 |
-40:13:41.0 |
HIP 5686 |
25.12 |
| 2026-09-28 00:00 |
01:12:10.01 |
-40:14:22.2 |
HIP 5686 |
25.00 |
| 2026-09-28 12:00 |
01:12:03.69 |
-40:15:03.0 |
HIP 5686 |
24.98 |
| 2026-09-29 00:00 |
01:11:57.36 |
-40:15:43.2 |
HIP 5686 |
25.03 |
| 2026-09-29 12:00 |
01:11:51.01 |
-40:16:22.9 |
HIP 5686 |
25.17 |
| 2026-09-30 00:00 |
01:11:44.65 |
-40:17:02.1 |
HIP 5686 |
25.40 |
| 2026-09-30 12:00 |
01:11:38.27 |
-40:17:40.7 |
HIP 5490 |
25.05 |
| 2026-10-01 00:00 |
01:11:31.89 |
-40:18:18.9 |
HIP 5490 |
23.81 |
| 2026-10-01 12:00 |
01:11:25.49 |
-40:18:56.5 |
HIP 5490 |
22.59 |
| 2026-10-02 00:00 |
01:11:19.08 |
-40:19:33.6 |
HIP 5490 |
21.38 |
| 2026-10-02 12:00 |
01:11:12.65 |
-40:20:10.2 |
HIP 5490 |
20.21 |
| 2026-10-03 00:00 |
01:11:06.22 |
-40:20:46.2 |
HIP 5490 |
19.07 |
| 2026-10-03 12:00 |
01:10:59.78 |
-40:21:21.7 |
HIP 5490 |
17.97 |
| 2026-10-04 00:00 |
01:10:53.33 |
-40:21:56.7 |
HIP 5490 |
16.91 |
| 2026-10-04 12:00 |
01:10:46.87 |
-40:22:31.1 |
HIP 5490 |
15.91 |
| 2026-10-05 00:00 |
01:10:40.40 |
-40:23:05.0 |
HIP 5490 |
14.97 |
| 2026-10-05 12:00 |
01:10:33.92 |
-40:23:38.3 |
HIP 5490 |
14.11 |
| 2026-10-06 00:00 |
01:10:27.44 |
-40:24:11.1 |
HIP 5490 |
13.34 |
| 2026-10-06 12:00 |
01:10:20.95 |
-40:24:43.3 |
HIP 5490 |
12.67 |
| 2026-10-07 00:00 |
01:10:14.46 |
-40:25:15.0 |
HIP 5490 |
12.13 |
| 2026-10-07 12:00 |
01:10:07.96 |
-40:25:46.1 |
HIP 5490 |
11.72 |
| 2026-10-08 00:00 |
01:10:01.46 |
-40:26:16.7 |
HIP 5490 |
11.47 |
| 2026-10-08 12:00 |
01:09:54.95 |
-40:26:46.7 |
HIP 5490 |
11.38 |
| 2026-10-09 00:00 |
01:09:48.44 |
-40:27:16.1 |
HIP 5490 |
11.45 |
| 2026-10-09 12:00 |
01:09:41.92 |
-40:27:45.0 |
HIP 5490 |
11.69 |
| 2026-10-10 00:00 |
01:09:35.41 |
-40:28:13.3 |
HIP 5490 |
12.07 |
| 2026-10-10 12:00 |
01:09:28.89 |
-40:28:41.0 |
HIP 5490 |
12.59 |
| 2026-10-11 00:00 |
01:09:22.38 |
-40:29:08.1 |
HIP 5490 |
13.22 |