메타데이터
| 항목 |
값 |
| Designation |
C/2018 A4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-05-18T19:21:20.165760Z |
| Orbit solution date (soln_date, UTC) |
2023-05-03T22:42:49Z |
| Obs used |
79 |
| NEO |
- |
| M1 |
8.400 |
| K1 |
22.250 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2018-01-15.0000000 |
| e |
0.80435873 |
| q (au) |
2.402567 |
| a (au) |
12.280471 |
| i (deg) |
3.148025 |
| Ω (om, deg) |
97.634759 |
| ω (w, deg) |
356.135345 |
| M (ma, deg) |
357.164531 |
밝기
산란 + 전체 선형
$$
M_a = (10.536 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.536 |
| 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) |
| 2026-05-12 00:00 |
16:30:18.48 |
-20:09:18.7 |
HIP 81004 |
32.14 |
| 2026-05-12 12:00 |
16:30:11.62 |
-20:09:03.5 |
HIP 81004 |
33.69 |
| 2026-05-13 00:00 |
16:30:04.73 |
-20:08:48.3 |
HIP 81004 |
35.26 |
| 2026-05-13 12:00 |
16:29:57.83 |
-20:08:33.1 |
HIP 81004 |
36.84 |
| 2026-05-14 00:00 |
16:29:50.90 |
-20:08:17.9 |
HIP 81004 |
38.43 |
| 2026-05-14 12:00 |
16:29:43.95 |
-20:08:02.6 |
HIP 81004 |
40.03 |
| 2026-05-15 00:00 |
16:29:36.98 |
-20:07:47.2 |
HIP 81004 |
41.64 |
| 2026-05-15 12:00 |
16:29:29.99 |
-20:07:31.9 |
HIP 81004 |
43.26 |
| 2026-05-16 00:00 |
16:29:22.99 |
-20:07:16.5 |
HIP 81004 |
44.88 |
| 2026-05-16 12:00 |
16:29:15.96 |
-20:07:01.1 |
HIP 81004 |
46.52 |
| 2026-05-17 00:00 |
16:29:08.92 |
-20:06:45.6 |
HIP 81004 |
48.15 |
| 2026-05-17 12:00 |
16:29:01.86 |
-20:06:30.2 |
HIP 81004 |
49.80 |
| 2026-05-18 00:00 |
16:28:54.78 |
-20:06:14.7 |
HIP 80877 |
51.14 |
| 2026-05-18 12:00 |
16:28:47.69 |
-20:05:59.2 |
HIP 80464 |
49.77 |
| 2026-05-19 00:00 |
16:28:40.59 |
-20:05:43.7 |
HIP 80464 |
48.11 |
| 2026-05-19 12:00 |
16:28:33.47 |
-20:05:28.1 |
HIP 80464 |
46.45 |
| 2026-05-20 00:00 |
16:28:26.34 |
-20:05:12.5 |
HIP 80464 |
44.78 |
| 2026-05-20 12:00 |
16:28:19.19 |
-20:04:57.0 |
HIP 80464 |
43.11 |
| 2026-05-21 00:00 |
16:28:12.04 |
-20:04:41.4 |
HIP 80464 |
41.44 |
| 2026-05-21 12:00 |
16:28:04.88 |
-20:04:25.8 |
HIP 80464 |
39.78 |
| 2026-05-22 00:00 |
16:27:57.70 |
-20:04:10.1 |
HIP 80464 |
38.11 |
| 2026-05-22 12:00 |
16:27:50.52 |
-20:03:54.5 |
HIP 80464 |
36.45 |
| 2026-05-23 00:00 |
16:27:43.33 |
-20:03:38.9 |
HIP 80464 |
34.79 |
| 2026-05-23 12:00 |
16:27:36.13 |
-20:03:23.2 |
HIP 80464 |
33.13 |
| 2026-05-24 00:00 |
16:27:28.92 |
-20:03:07.6 |
HIP 80464 |
31.47 |
| 2026-05-24 12:00 |
16:27:21.71 |
-20:02:51.9 |
HIP 80464 |
29.82 |
| 2026-05-25 00:00 |
16:27:14.49 |
-20:02:36.3 |
HIP 80464 |
28.18 |
| 2026-05-25 12:00 |
16:27:07.26 |
-20:02:20.6 |
HIP 80464 |
26.55 |
| 2026-05-26 00:00 |
16:27:00.04 |
-20:02:05.0 |
HIP 80464 |
24.92 |
| 2026-05-26 12:00 |
16:26:52.80 |
-20:01:49.3 |
HIP 80464 |
23.31 |
| 2026-05-27 00:00 |
16:26:45.57 |
-20:01:33.7 |
HIP 80464 |
21.71 |
| 2026-05-27 12:00 |
16:26:38.33 |
-20:01:18.0 |
HIP 80464 |
20.14 |
| 2026-05-28 00:00 |
16:26:31.10 |
-20:01:02.4 |
HIP 80464 |
18.59 |
| 2026-05-28 12:00 |
16:26:23.86 |
-20:00:46.8 |
HIP 80464 |
17.07 |
| 2026-05-29 00:00 |
16:26:16.62 |
-20:00:31.2 |
HIP 80464 |
15.60 |
| 2026-05-29 12:00 |
16:26:09.38 |
-20:00:15.6 |
HIP 80464 |
14.18 |
| 2026-05-30 00:00 |
16:26:02.14 |
-20:00:00.0 |
HIP 80464 |
12.83 |
| 2026-05-30 12:00 |
16:25:54.91 |
-19:59:44.4 |
HIP 80464 |
11.58 |
| 2026-05-31 00:00 |
16:25:47.68 |
-19:59:28.8 |
HIP 80464 |
10.48 |
| 2026-05-31 12:00 |
16:25:40.45 |
-19:59:13.3 |
HIP 80464 |
9.55 |
| 2026-06-01 00:00 |
16:25:33.22 |
-19:58:57.7 |
HIP 80464 |
8.86 |
| 2026-06-01 12:00 |
16:25:26.00 |
-19:58:42.2 |
HIP 80464 |
8.47 |
| 2026-06-02 00:00 |
16:25:18.79 |
-19:58:26.8 |
HIP 80464 |
8.42 |