메타데이터
| 항목 |
값 |
| Designation |
C/2019 T2 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-04-22T06:32:53.350080Z |
| Orbit solution date (soln_date, UTC) |
2023-08-06T18:12:27Z |
| Obs used |
187 |
| NEO |
- |
| M1 |
12.700 |
| K1 |
5.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-10-09T03:16:41.376000Z |
| Discovery magnitude (MPC) |
20.60 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2021-02-26.0000000 |
| e |
0.99872185 |
| q (au) |
2.645893 |
| a (au) |
2070.091183 |
| i (deg) |
111.488095 |
| Ω (om, deg) |
155.641811 |
| ω (w, deg) |
239.386315 |
| M (ma, deg) |
359.999422 |
밝기
산란 + 전체 선형
$$
M_a = (11.950 + 3.858\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
11.950 |
| n |
3.858 |
| gf |
1.000 |
| gb |
-0.704 |
| k |
0.800 |
| 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 |
| 2019-08-26 |
2019-11-30 |
+22.3714 |
-17.071 |
| 2019-11-30 |
2020-07-16 |
-0.1476 |
-0.346 |
| 2020-07-16 |
2020-10-26 |
-4.8324 |
+2.665 |
| 2020-10-26 |
2021-04-11 |
-2.5155 |
+1.291 |
| 2021-05-22 |
2022-01-22 |
-5.7468 |
+3.701 |
| 2022-01-22 |
2023-06-14 |
+4.9021 |
-2.908 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
10:21:38.82 |
+18:49:44.1 |
HIP 50848 |
26.27 |
| 2026-03-26 12:00 |
10:21:31.36 |
+18:50:35.7 |
HIP 50848 |
27.01 |
| 2026-03-27 00:00 |
10:21:23.95 |
+18:51:26.9 |
HIP 50848 |
27.87 |
| 2026-03-27 12:00 |
10:21:16.59 |
+18:52:17.7 |
HIP 50848 |
28.83 |
| 2026-03-28 00:00 |
10:21:09.28 |
+18:53:08.0 |
HIP 50848 |
29.87 |
| 2026-03-28 12:00 |
10:21:02.02 |
+18:53:57.8 |
HIP 50848 |
30.99 |
| 2026-03-29 00:00 |
10:20:54.80 |
+18:54:47.2 |
HIP 50848 |
32.18 |
| 2026-03-29 12:00 |
10:20:47.64 |
+18:55:36.2 |
HIP 50848 |
33.43 |
| 2026-03-30 00:00 |
10:20:40.53 |
+18:56:24.7 |
HIP 50564 |
34.53 |
| 2026-03-30 12:00 |
10:20:33.47 |
+18:57:12.7 |
HIP 50564 |
33.17 |
| 2026-03-31 00:00 |
10:20:26.47 |
+18:58:00.3 |
HIP 50564 |
31.87 |
| 2026-03-31 12:00 |
10:20:19.51 |
+18:58:47.4 |
HIP 50564 |
30.64 |
| 2026-04-01 00:00 |
10:20:12.61 |
+18:59:34.1 |
HIP 50564 |
29.48 |
| 2026-04-01 12:00 |
10:20:05.77 |
+19:00:20.3 |
HIP 50564 |
28.40 |
| 2026-04-02 00:00 |
10:19:58.97 |
+19:01:06.1 |
HIP 50564 |
27.40 |
| 2026-04-02 12:00 |
10:19:52.23 |
+19:01:51.4 |
HIP 50564 |
26.50 |
| 2026-04-03 00:00 |
10:19:45.55 |
+19:02:36.2 |
HIP 50564 |
25.68 |
| 2026-04-03 12:00 |
10:19:38.92 |
+19:03:20.6 |
HIP 50564 |
24.98 |
| 2026-04-04 00:00 |
10:19:32.35 |
+19:04:04.5 |
HIP 50564 |
24.38 |
| 2026-04-04 12:00 |
10:19:25.83 |
+19:04:48.0 |
HIP 50564 |
23.89 |
| 2026-04-05 00:00 |
10:19:19.37 |
+19:05:30.9 |
HIP 50564 |
23.52 |
| 2026-04-05 12:00 |
10:19:12.97 |
+19:06:13.5 |
HIP 50564 |
23.27 |
| 2026-04-06 00:00 |
10:19:06.62 |
+19:06:55.5 |
HIP 50564 |
23.14 |
| 2026-04-06 12:00 |
10:19:00.34 |
+19:07:37.1 |
HIP 50564 |
23.13 |
| 2026-04-07 00:00 |
10:18:54.11 |
+19:08:18.2 |
HIP 50564 |
23.23 |
| 2026-04-07 12:00 |
10:18:47.94 |
+19:08:58.9 |
HIP 50564 |
23.44 |
| 2026-04-08 00:00 |
10:18:41.83 |
+19:09:39.1 |
HIP 50564 |
23.76 |
| 2026-04-08 12:00 |
10:18:35.78 |
+19:10:18.8 |
HIP 50564 |
24.17 |
| 2026-04-09 00:00 |
10:18:29.79 |
+19:10:58.1 |
HIP 50564 |
24.68 |
| 2026-04-09 12:00 |
10:18:23.86 |
+19:11:36.8 |
HIP 50564 |
25.26 |
| 2026-04-10 00:00 |
10:18:17.99 |
+19:12:15.2 |
HIP 50564 |
25.92 |
| 2026-04-10 12:00 |
10:18:12.18 |
+19:12:53.0 |
HIP 50564 |
26.64 |
| 2026-04-11 00:00 |
10:18:06.44 |
+19:13:30.4 |
HIP 50564 |
27.41 |
| 2026-04-11 12:00 |
10:18:00.75 |
+19:14:07.3 |
HIP 50564 |
28.24 |
| 2026-04-12 00:00 |
10:17:55.13 |
+19:14:43.7 |
HIP 50375 |
28.75 |
| 2026-04-12 12:00 |
10:17:49.58 |
+19:15:19.6 |
HIP 50375 |
28.84 |
| 2026-04-13 00:00 |
10:17:44.08 |
+19:15:55.1 |
HIP 50375 |
28.99 |
| 2026-04-13 12:00 |
10:17:38.65 |
+19:16:30.1 |
HIP 50375 |
29.21 |
| 2026-04-14 00:00 |
10:17:33.28 |
+19:17:04.6 |
HIP 50375 |
29.49 |
| 2026-04-14 12:00 |
10:17:27.98 |
+19:17:38.7 |
HIP 50375 |
29.82 |
| 2026-04-15 00:00 |
10:17:22.74 |
+19:18:12.3 |
HIP 50375 |
30.21 |
| 2026-04-15 12:00 |
10:17:17.57 |
+19:18:45.4 |
HIP 50375 |
30.65 |
| 2026-04-16 00:00 |
10:17:12.46 |
+19:19:18.0 |
HIP 50375 |
31.13 |