메타데이터
| 항목 |
값 |
| Designation |
C/2019 U6 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-06-18T19:43:24.988800Z |
| Orbit solution date (soln_date, UTC) |
2022-04-16T22:12:22Z |
| Obs used |
1144 |
| NEO |
- |
| M1 |
13.200 |
| K1 |
7.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-10-31T10:24:29.952000Z |
| Discovery magnitude (MPC) |
20.50 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2020-04-28.0000000 |
| e |
0.99790319 |
| q (au) |
0.914264 |
| a (au) |
436.025928 |
| i (deg) |
61.001339 |
| Ω (om, deg) |
235.705755 |
| ω (w, deg) |
329.659058 |
| M (ma, deg) |
359.994390 |
밝기
산란 + 전체 선형
$$
M_a = (8.998 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
8.998 |
| 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
잔차 (구간 선형)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 시작일 (UTC) |
끝 (UTC) |
a |
b |
| 2018-11-06 |
2020-01-26 |
-9.9490 |
+4.967 |
| 2020-01-26 |
2020-04-22 |
+11.1473 |
-3.130 |
| 2020-04-22 |
2020-06-18 |
-1.0370 |
-2.413 |
| 2020-06-18 |
2020-07-26 |
+16.3476 |
-0.540 |
| 2020-07-26 |
2020-11-28 |
-5.2648 |
+1.320 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
23:47:16.88 |
+51:43:55.6 |
HIP 117379 |
9.02 |
| 2026-07-29 12:00 |
23:47:11.29 |
+51:44:38.6 |
HIP 117379 |
9.21 |
| 2026-07-30 00:00 |
23:47:05.64 |
+51:45:21.0 |
HIP 117379 |
9.54 |
| 2026-07-30 12:00 |
23:46:59.92 |
+51:46:02.8 |
HIP 117379 |
10.00 |
| 2026-07-31 00:00 |
23:46:54.13 |
+51:46:44.0 |
HIP 117379 |
10.58 |
| 2026-07-31 12:00 |
23:46:48.27 |
+51:47:24.6 |
HIP 117293 |
10.07 |
| 2026-08-01 00:00 |
23:46:42.35 |
+51:48:04.6 |
HIP 117293 |
9.61 |
| 2026-08-01 12:00 |
23:46:36.36 |
+51:48:44.0 |
HIP 117293 |
9.27 |
| 2026-08-02 00:00 |
23:46:30.31 |
+51:49:22.8 |
HIP 117293 |
9.08 |
| 2026-08-02 12:00 |
23:46:24.19 |
+51:50:01.0 |
HIP 117293 |
9.04 |
| 2026-08-03 00:00 |
23:46:18.00 |
+51:50:38.6 |
HIP 117293 |
9.16 |
| 2026-08-03 12:00 |
23:46:11.75 |
+51:51:15.6 |
HIP 117293 |
9.43 |
| 2026-08-04 00:00 |
23:46:05.43 |
+51:51:51.9 |
HIP 117293 |
9.84 |
| 2026-08-04 12:00 |
23:45:59.06 |
+51:52:27.7 |
HIP 117293 |
10.37 |
| 2026-08-05 00:00 |
23:45:52.61 |
+51:53:02.7 |
HIP 117293 |
11.01 |
| 2026-08-05 12:00 |
23:45:46.11 |
+51:53:37.2 |
HIP 117293 |
11.75 |
| 2026-08-06 00:00 |
23:45:39.54 |
+51:54:11.0 |
HIP 117293 |
12.55 |
| 2026-08-06 12:00 |
23:45:32.91 |
+51:54:44.2 |
HIP 117293 |
13.43 |
| 2026-08-07 00:00 |
23:45:26.22 |
+51:55:16.7 |
HIP 117293 |
14.35 |
| 2026-08-07 12:00 |
23:45:19.47 |
+51:55:48.6 |
HIP 117293 |
15.31 |
| 2026-08-08 00:00 |
23:45:12.66 |
+51:56:19.8 |
HIP 117293 |
16.32 |
| 2026-08-08 12:00 |
23:45:05.79 |
+51:56:50.4 |
HIP 117293 |
17.35 |
| 2026-08-09 00:00 |
23:44:58.86 |
+51:57:20.3 |
HIP 116991 |
17.57 |
| 2026-08-09 12:00 |
23:44:51.87 |
+51:57:49.5 |
HIP 116991 |
16.53 |
| 2026-08-10 00:00 |
23:44:44.82 |
+51:58:18.1 |
HIP 116991 |
15.50 |
| 2026-08-10 12:00 |
23:44:37.72 |
+51:58:46.0 |
HIP 116991 |
14.48 |
| 2026-08-11 00:00 |
23:44:30.55 |
+51:59:13.2 |
HIP 116991 |
13.48 |
| 2026-08-11 12:00 |
23:44:23.33 |
+51:59:39.7 |
HIP 116991 |
12.51 |
| 2026-08-12 00:00 |
23:44:16.06 |
+52:00:05.5 |
HIP 116991 |
11.56 |
| 2026-08-12 12:00 |
23:44:08.73 |
+52:00:30.7 |
HIP 116991 |
10.65 |
| 2026-08-13 00:00 |
23:44:01.35 |
+52:00:55.1 |
HIP 116991 |
9.80 |
| 2026-08-13 12:00 |
23:43:53.91 |
+52:01:18.9 |
HIP 116991 |
9.01 |
| 2026-08-14 00:00 |
23:43:46.42 |
+52:01:41.9 |
HIP 116991 |
8.31 |
| 2026-08-14 12:00 |
23:43:38.88 |
+52:02:04.3 |
HIP 116991 |
7.73 |
| 2026-08-15 00:00 |
23:43:31.29 |
+52:02:25.9 |
HIP 116991 |
7.29 |
| 2026-08-15 12:00 |
23:43:23.64 |
+52:02:46.9 |
HIP 116991 |
7.03 |
| 2026-08-16 00:00 |
23:43:15.95 |
+52:03:07.1 |
HIP 116991 |
6.96 |
| 2026-08-16 12:00 |
23:43:08.20 |
+52:03:26.6 |
HIP 116991 |
7.10 |
| 2026-08-17 00:00 |
23:43:00.41 |
+52:03:45.4 |
HIP 116991 |
7.43 |
| 2026-08-17 12:00 |
23:42:52.57 |
+52:04:03.5 |
HIP 116991 |
7.93 |
| 2026-08-18 00:00 |
23:42:44.69 |
+52:04:20.9 |
HIP 116991 |
8.58 |
| 2026-08-18 12:00 |
23:42:36.75 |
+52:04:37.5 |
HIP 116991 |
9.34 |
| 2026-08-19 00:00 |
23:42:28.78 |
+52:04:53.4 |
HIP 116991 |
10.19 |