메타데이터
| 항목 |
값 |
| Designation |
C/2018 L2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-12-02T13:55:55.485120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:44Z |
| Obs used |
731 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
10.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-06-06T07:58:35.040000Z |
| Discovery magnitude (MPC) |
15.60 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2018-12-29.0000000 |
| e |
0.99298130 |
| q (au) |
1.711711 |
| a (au) |
243.878556 |
| i (deg) |
67.423590 |
| Ω (om, deg) |
243.018259 |
| ω (w, deg) |
56.230818 |
| M (ma, deg) |
0.006837 |
밝기
산란 + 전체 선형
$$
M_a = (8.836 + 4.978\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
8.836 |
| n |
4.978 |
| gf |
1.000 |
| gb |
-0.767 |
| k |
0.985 |
| 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 |
| 2018-06-04 |
2018-09-08 |
+4.1202 |
-1.557 |
| 2018-09-08 |
2018-12-01 |
+25.5943 |
-7.920 |
| 2018-12-03 |
2020-01-20 |
+2.8927 |
-2.045 |
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 |
04:42:07.39 |
+01:54:35.9 |
HIP 21826 |
8.82 |
| 2026-03-26 12:00 |
04:42:10.02 |
+01:55:01.6 |
HIP 21826 |
9.51 |
| 2026-03-27 00:00 |
04:42:12.69 |
+01:55:27.3 |
HIP 21826 |
10.23 |
| 2026-03-27 12:00 |
04:42:15.41 |
+01:55:53.0 |
HIP 21826 |
10.97 |
| 2026-03-28 00:00 |
04:42:18.17 |
+01:56:18.6 |
HIP 21826 |
11.73 |
| 2026-03-28 12:00 |
04:42:20.98 |
+01:56:44.2 |
HIP 21826 |
12.50 |
| 2026-03-29 00:00 |
04:42:23.83 |
+01:57:09.7 |
HIP 21826 |
13.29 |
| 2026-03-29 12:00 |
04:42:26.72 |
+01:57:35.1 |
HIP 21826 |
14.10 |
| 2026-03-30 00:00 |
04:42:29.65 |
+01:58:00.5 |
HIP 21826 |
14.92 |
| 2026-03-30 12:00 |
04:42:32.63 |
+01:58:25.8 |
HIP 21826 |
15.75 |
| 2026-03-31 00:00 |
04:42:35.64 |
+01:58:51.1 |
HIP 21826 |
16.59 |
| 2026-03-31 12:00 |
04:42:38.70 |
+01:59:16.3 |
HIP 21826 |
17.44 |
| 2026-04-01 00:00 |
04:42:41.81 |
+01:59:41.4 |
HIP 21826 |
18.31 |
| 2026-04-01 12:00 |
04:42:44.95 |
+02:00:06.5 |
HIP 21826 |
19.19 |
| 2026-04-02 00:00 |
04:42:48.13 |
+02:00:31.5 |
HIP 21826 |
20.08 |
| 2026-04-02 12:00 |
04:42:51.36 |
+02:00:56.4 |
HIP 21826 |
20.97 |
| 2026-04-03 00:00 |
04:42:54.62 |
+02:01:21.2 |
HIP 21826 |
21.88 |
| 2026-04-03 12:00 |
04:42:57.93 |
+02:01:46.0 |
HIP 21826 |
22.80 |
| 2026-04-04 00:00 |
04:43:01.27 |
+02:02:10.7 |
HIP 21936 |
22.95 |
| 2026-04-04 12:00 |
04:43:04.66 |
+02:02:35.3 |
HIP 21936 |
22.59 |
| 2026-04-05 00:00 |
04:43:08.08 |
+02:02:59.8 |
HIP 21936 |
22.27 |
| 2026-04-05 12:00 |
04:43:11.54 |
+02:03:24.3 |
HIP 21936 |
21.99 |
| 2026-04-06 00:00 |
04:43:15.05 |
+02:03:48.6 |
HIP 21936 |
21.75 |
| 2026-04-06 12:00 |
04:43:18.59 |
+02:04:12.9 |
HIP 21936 |
21.56 |
| 2026-04-07 00:00 |
04:43:22.17 |
+02:04:37.1 |
HIP 21936 |
21.41 |
| 2026-04-07 12:00 |
04:43:25.79 |
+02:05:01.1 |
HIP 21936 |
21.31 |
| 2026-04-08 00:00 |
04:43:29.44 |
+02:05:25.1 |
HIP 21936 |
21.26 |
| 2026-04-08 12:00 |
04:43:33.14 |
+02:05:49.0 |
HIP 21936 |
21.26 |
| 2026-04-09 00:00 |
04:43:36.87 |
+02:06:12.8 |
HIP 21936 |
21.32 |
| 2026-04-09 12:00 |
04:43:40.64 |
+02:06:36.5 |
HIP 21936 |
21.43 |
| 2026-04-10 00:00 |
04:43:44.44 |
+02:07:00.1 |
HIP 21936 |
21.59 |
| 2026-04-10 12:00 |
04:43:48.28 |
+02:07:23.6 |
HIP 21936 |
21.81 |
| 2026-04-11 00:00 |
04:43:52.16 |
+02:07:47.0 |
HIP 21936 |
22.08 |
| 2026-04-11 12:00 |
04:43:56.07 |
+02:08:10.2 |
HIP 21936 |
22.41 |
| 2026-04-12 00:00 |
04:44:00.02 |
+02:08:33.4 |
HIP 21936 |
22.78 |
| 2026-04-12 12:00 |
04:44:04.01 |
+02:08:56.4 |
HIP 21936 |
23.21 |
| 2026-04-13 00:00 |
04:44:08.03 |
+02:09:19.4 |
HIP 21936 |
23.68 |
| 2026-04-13 12:00 |
04:44:12.09 |
+02:09:42.2 |
HIP 21936 |
24.20 |
| 2026-04-14 00:00 |
04:44:16.18 |
+02:10:04.9 |
HIP 21936 |
24.77 |
| 2026-04-14 12:00 |
04:44:20.30 |
+02:10:27.4 |
HIP 21936 |
25.38 |
| 2026-04-15 00:00 |
04:44:24.46 |
+02:10:49.9 |
HIP 21936 |
26.02 |
| 2026-04-15 12:00 |
04:44:28.65 |
+02:11:12.2 |
HIP 21936 |
26.71 |
| 2026-04-16 00:00 |
04:44:32.88 |
+02:11:34.4 |
HIP 21936 |
27.43 |