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 |
-0.500 |
| 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) |
| 2026-03-26 00:00 |
01:03:53.45 |
-36:14:39.4 |
HIP 4986 |
1.23 |
| 2026-03-26 12:00 |
01:04:00.00 |
-36:14:10.4 |
HIP 4986 |
1.82 |
| 2026-03-27 00:00 |
01:04:06.57 |
-36:13:41.8 |
HIP 4986 |
3.00 |
| 2026-03-27 12:00 |
01:04:13.14 |
-36:13:13.6 |
HIP 4986 |
4.32 |
| 2026-03-28 00:00 |
01:04:19.72 |
-36:12:45.9 |
HIP 5050 |
4.11 |
| 2026-03-28 12:00 |
01:04:26.31 |
-36:12:18.6 |
HIP 5050 |
3.08 |
| 2026-03-29 00:00 |
01:04:32.90 |
-36:11:51.7 |
HIP 5050 |
2.44 |
| 2026-03-29 12:00 |
01:04:39.50 |
-36:11:25.2 |
HIP 5050 |
2.52 |
| 2026-03-30 00:00 |
01:04:46.11 |
-36:10:59.2 |
HIP 5050 |
3.26 |
| 2026-03-30 12:00 |
01:04:52.72 |
-36:10:33.6 |
HIP 5050 |
4.33 |
| 2026-03-31 00:00 |
01:04:59.34 |
-36:10:08.5 |
HIP 5050 |
5.55 |
| 2026-03-31 12:00 |
01:05:05.96 |
-36:09:43.7 |
HIP 5050 |
6.84 |
| 2026-04-01 00:00 |
01:05:12.59 |
-36:09:19.4 |
HIP 5050 |
8.15 |
| 2026-04-01 12:00 |
01:05:19.22 |
-36:08:55.6 |
HIP 5050 |
9.49 |
| 2026-04-02 00:00 |
01:05:25.86 |
-36:08:32.2 |
HIP 5050 |
10.84 |
| 2026-04-02 12:00 |
01:05:32.50 |
-36:08:09.2 |
HIP 5050 |
12.20 |
| 2026-04-03 00:00 |
01:05:39.15 |
-36:07:46.7 |
HIP 5050 |
13.56 |
| 2026-04-03 12:00 |
01:05:45.79 |
-36:07:24.6 |
HIP 5050 |
14.93 |
| 2026-04-04 00:00 |
01:05:52.44 |
-36:07:03.0 |
HIP 5050 |
16.30 |
| 2026-04-04 12:00 |
01:05:59.10 |
-36:06:41.8 |
HIP 5050 |
17.66 |
| 2026-04-05 00:00 |
01:06:05.75 |
-36:06:21.0 |
HIP 5050 |
19.03 |
| 2026-04-05 12:00 |
01:06:12.41 |
-36:06:00.8 |
HIP 5050 |
20.40 |
| 2026-04-06 00:00 |
01:06:19.06 |
-36:05:40.9 |
HIP 5050 |
21.77 |
| 2026-04-06 12:00 |
01:06:25.72 |
-36:05:21.6 |
HIP 5050 |
23.14 |
| 2026-04-07 00:00 |
01:06:32.38 |
-36:05:02.6 |
HIP 5050 |
24.50 |
| 2026-04-07 12:00 |
01:06:39.04 |
-36:04:44.2 |
HIP 5193 |
25.23 |
| 2026-04-08 00:00 |
01:06:45.70 |
-36:04:26.2 |
HIP 5193 |
25.10 |
| 2026-04-08 12:00 |
01:06:52.36 |
-36:04:08.6 |
HIP 5193 |
25.06 |
| 2026-04-09 00:00 |
01:06:59.01 |
-36:03:51.5 |
HIP 5193 |
25.10 |
| 2026-04-09 12:00 |
01:07:05.67 |
-36:03:34.9 |
HIP 5193 |
25.22 |
| 2026-04-10 00:00 |
01:07:12.32 |
-36:03:18.8 |
HIP 5402 |
24.04 |
| 2026-04-10 12:00 |
01:07:18.97 |
-36:03:03.1 |
HIP 5402 |
22.79 |
| 2026-04-11 00:00 |
01:07:25.62 |
-36:02:47.9 |
HIP 5402 |
21.56 |
| 2026-04-11 12:00 |
01:07:32.27 |
-36:02:33.1 |
HIP 5402 |
20.34 |
| 2026-04-12 00:00 |
01:07:38.91 |
-36:02:18.8 |
HIP 5402 |
19.14 |
| 2026-04-12 12:00 |
01:07:45.55 |
-36:02:05.0 |
HIP 5402 |
17.96 |
| 2026-04-13 00:00 |
01:07:52.19 |
-36:01:51.7 |
HIP 5402 |
16.81 |
| 2026-04-13 12:00 |
01:07:58.82 |
-36:01:38.9 |
HIP 5402 |
15.69 |
| 2026-04-14 00:00 |
01:08:05.45 |
-36:01:26.5 |
HIP 5402 |
14.60 |
| 2026-04-14 12:00 |
01:08:12.07 |
-36:01:14.6 |
HIP 5402 |
13.55 |
| 2026-04-15 00:00 |
01:08:18.68 |
-36:01:03.2 |
HIP 5402 |
12.56 |
| 2026-04-15 12:00 |
01:08:25.29 |
-36:00:52.3 |
HIP 5402 |
11.64 |
| 2026-04-16 00:00 |
01:08:31.90 |
-36:00:41.8 |
HIP 5402 |
10.81 |