메타데이터
| 항목 |
값 |
| Designation |
C/2020 M5 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-08-19T21:12:41.952960Z |
| Orbit solution date (soln_date, UTC) |
2023-03-28T19:42:35Z |
| Obs used |
1605 |
| NEO |
- |
| M1 |
7.600 |
| K1 |
11.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-06-30T13:19:39.388800Z |
| Discovery magnitude (MPC) |
19.44 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2021-08-02.0000000 |
| e |
0.99994908 |
| q (au) |
3.004334 |
| a (au) |
59004.546918 |
| i (deg) |
93.222721 |
| Ω (om, deg) |
352.095028 |
| ω (w, deg) |
126.340033 |
| M (ma, deg) |
359.999999 |
밝기
산란 + 전체 선형
$$
M_a = (8.967 + 5.727\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
8.967 |
| n |
5.727 |
| gf |
1.000 |
| gb |
-0.785 |
| 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 |
| 2019-08-10 |
2021-08-18 |
+1.0283 |
-0.456 |
| 2021-08-23 |
2022-02-06 |
-4.3432 |
+1.747 |
| 2022-02-06 |
2022-04-28 |
-5.1639 |
+2.582 |
| 2022-04-28 |
2023-02-27 |
-0.1853 |
-0.920 |
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 |
08:18:38.57 |
-51:51:49.1 |
HIP 40668 |
7.92 |
| 2026-07-29 12:00 |
08:18:49.57 |
-51:52:21.9 |
HIP 40668 |
8.66 |
| 2026-07-30 00:00 |
08:19:00.57 |
-51:52:55.7 |
HIP 40824 |
9.53 |
| 2026-07-30 12:00 |
08:19:11.55 |
-51:53:30.3 |
HIP 40824 |
7.74 |
| 2026-07-31 00:00 |
08:19:22.52 |
-51:54:05.8 |
HIP 40824 |
5.96 |
| 2026-07-31 12:00 |
08:19:33.48 |
-51:54:42.2 |
HIP 40824 |
4.17 |
| 2026-08-01 00:00 |
08:19:44.43 |
-51:55:19.5 |
HIP 40824 |
2.38 |
| 2026-08-01 12:00 |
08:19:55.37 |
-51:55:57.6 |
HIP 40824 |
0.67 |
| 2026-08-02 00:00 |
08:20:06.30 |
-51:56:36.7 |
HIP 40824 |
1.31 |
| 2026-08-02 12:00 |
08:20:17.21 |
-51:57:16.6 |
HIP 40824 |
3.08 |
| 2026-08-03 00:00 |
08:20:28.11 |
-51:57:57.4 |
HIP 40824 |
4.88 |
| 2026-08-03 12:00 |
08:20:38.99 |
-51:58:39.0 |
HIP 40824 |
6.69 |
| 2026-08-04 00:00 |
08:20:49.86 |
-51:59:21.6 |
HIP 40824 |
8.51 |
| 2026-08-04 12:00 |
08:21:00.71 |
-52:00:05.0 |
HIP 40824 |
10.32 |
| 2026-08-05 00:00 |
08:21:11.55 |
-52:00:49.3 |
HIP 40824 |
12.14 |
| 2026-08-05 12:00 |
08:21:22.36 |
-52:01:34.5 |
HIP 40916 |
12.56 |
| 2026-08-06 00:00 |
08:21:33.16 |
-52:02:20.5 |
HIP 40916 |
12.40 |
| 2026-08-06 12:00 |
08:21:43.95 |
-52:03:07.4 |
HIP 41081 |
11.76 |
| 2026-08-07 00:00 |
08:21:54.71 |
-52:03:55.2 |
HIP 41081 |
9.93 |
| 2026-08-07 12:00 |
08:22:05.45 |
-52:04:43.8 |
HIP 41081 |
8.10 |
| 2026-08-08 00:00 |
08:22:16.17 |
-52:05:33.3 |
HIP 41081 |
6.27 |
| 2026-08-08 12:00 |
08:22:26.87 |
-52:06:23.6 |
HIP 41081 |
4.47 |
| 2026-08-09 00:00 |
08:22:37.55 |
-52:07:14.9 |
HIP 41081 |
2.71 |
| 2026-08-09 12:00 |
08:22:48.21 |
-52:08:06.9 |
HIP 41081 |
1.27 |
| 2026-08-10 00:00 |
08:22:58.84 |
-52:08:59.9 |
HIP 41081 |
1.67 |
| 2026-08-10 12:00 |
08:23:09.45 |
-52:09:53.7 |
HIP 41081 |
3.30 |
| 2026-08-11 00:00 |
08:23:20.03 |
-52:10:48.3 |
HIP 41081 |
5.09 |
| 2026-08-11 12:00 |
08:23:30.59 |
-52:11:43.8 |
HIP 41081 |
6.93 |
| 2026-08-12 00:00 |
08:23:41.12 |
-52:12:40.1 |
HIP 41081 |
8.78 |
| 2026-08-12 12:00 |
08:23:51.62 |
-52:13:37.3 |
HIP 41081 |
10.64 |
| 2026-08-13 00:00 |
08:24:02.10 |
-52:14:35.3 |
HIP 41081 |
12.51 |
| 2026-08-13 12:00 |
08:24:12.54 |
-52:15:34.2 |
HIP 41081 |
14.38 |
| 2026-08-14 00:00 |
08:24:22.96 |
-52:16:33.9 |
HIP 41081 |
16.26 |
| 2026-08-14 12:00 |
08:24:33.35 |
-52:17:34.4 |
HIP 41160 |
16.60 |
| 2026-08-15 00:00 |
08:24:43.70 |
-52:18:35.8 |
HIP 41160 |
16.35 |
| 2026-08-15 12:00 |
08:24:54.03 |
-52:19:38.0 |
HIP 41160 |
16.31 |
| 2026-08-16 00:00 |
08:25:04.32 |
-52:20:41.0 |
HIP 41160 |
16.47 |
| 2026-08-16 12:00 |
08:25:14.58 |
-52:21:44.8 |
HIP 41160 |
16.83 |
| 2026-08-17 00:00 |
08:25:24.80 |
-52:22:49.4 |
HIP 41160 |
17.37 |
| 2026-08-17 12:00 |
08:25:34.99 |
-52:23:54.9 |
HIP 41160 |
18.08 |
| 2026-08-18 00:00 |
08:25:45.15 |
-52:25:01.1 |
HIP 41160 |
18.95 |
| 2026-08-18 12:00 |
08:25:55.27 |
-52:26:08.2 |
HIP 41426 |
18.74 |
| 2026-08-19 00:00 |
08:26:05.35 |
-52:27:16.1 |
HIP 41426 |
17.01 |