메타데이터
| 항목 |
값 |
| Designation |
P/2017 G2 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-06-13T21:56:20.866560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:32Z |
| Obs used |
165 |
| NEO |
- |
| M1 |
12.900 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-05-16.0000000 |
| e |
0.65031280 |
| q (au) |
2.846253 |
| a (au) |
8.139426 |
| i (deg) |
47.906245 |
| Ω (om, deg) |
79.819627 |
| ω (w, deg) |
105.939134 |
| M (ma, deg) |
358.772777 |
밝기
산란 + 전체 선형
$$
M_a = (9.648 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
9.648 |
| 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) |
| 2026-07-29 00:00 |
01:49:43.30 |
-43:19:54.7 |
HIP 8437 |
11.97 |
| 2026-07-29 12:00 |
01:49:43.45 |
-43:21:35.2 |
HIP 8437 |
12.89 |
| 2026-07-30 00:00 |
01:49:43.49 |
-43:23:15.9 |
HIP 8437 |
13.93 |
| 2026-07-30 12:00 |
01:49:43.44 |
-43:24:56.8 |
HIP 8437 |
15.07 |
| 2026-07-31 00:00 |
01:49:43.28 |
-43:26:37.8 |
HIP 8437 |
16.30 |
| 2026-07-31 12:00 |
01:49:43.03 |
-43:28:19.0 |
HIP 8437 |
17.60 |
| 2026-08-01 00:00 |
01:49:42.67 |
-43:30:00.4 |
HIP 8437 |
18.95 |
| 2026-08-01 12:00 |
01:49:42.21 |
-43:31:42.0 |
HIP 8634 |
20.34 |
| 2026-08-02 00:00 |
01:49:41.65 |
-43:33:23.6 |
HIP 8634 |
21.28 |
| 2026-08-02 12:00 |
01:49:40.99 |
-43:35:05.5 |
HIP 8634 |
22.32 |
| 2026-08-03 00:00 |
01:49:40.23 |
-43:36:47.4 |
HIP 8634 |
23.46 |
| 2026-08-03 12:00 |
01:49:39.36 |
-43:38:29.5 |
HIP 8634 |
24.68 |
| 2026-08-04 00:00 |
01:49:38.40 |
-43:40:11.6 |
HIP 8634 |
25.96 |
| 2026-08-04 12:00 |
01:49:37.33 |
-43:41:53.9 |
HIP 8420 |
26.65 |
| 2026-08-05 00:00 |
01:49:36.16 |
-43:43:36.3 |
HIP 8420 |
25.01 |
| 2026-08-05 12:00 |
01:49:34.89 |
-43:45:18.8 |
HIP 8420 |
23.37 |
| 2026-08-06 00:00 |
01:49:33.51 |
-43:47:01.3 |
HIP 8420 |
21.74 |
| 2026-08-06 12:00 |
01:49:32.04 |
-43:48:43.9 |
HIP 8420 |
20.11 |
| 2026-08-07 00:00 |
01:49:30.46 |
-43:50:26.5 |
HIP 8420 |
18.49 |
| 2026-08-07 12:00 |
01:49:28.77 |
-43:52:09.2 |
HIP 8420 |
16.88 |
| 2026-08-08 00:00 |
01:49:26.99 |
-43:53:52.0 |
HIP 8420 |
15.30 |
| 2026-08-08 12:00 |
01:49:25.10 |
-43:55:34.7 |
HIP 8420 |
13.73 |
| 2026-08-09 00:00 |
01:49:23.11 |
-43:57:17.5 |
HIP 8420 |
12.20 |
| 2026-08-09 12:00 |
01:49:21.02 |
-43:59:00.3 |
HIP 8420 |
10.73 |
| 2026-08-10 00:00 |
01:49:18.82 |
-44:00:43.1 |
HIP 8420 |
9.34 |
| 2026-08-10 12:00 |
01:49:16.52 |
-44:02:25.9 |
HIP 8420 |
8.08 |
| 2026-08-11 00:00 |
01:49:14.12 |
-44:04:08.7 |
HIP 8420 |
7.02 |
| 2026-08-11 12:00 |
01:49:11.62 |
-44:05:51.4 |
HIP 8420 |
6.27 |
| 2026-08-12 00:00 |
01:49:09.01 |
-44:07:34.1 |
HIP 8420 |
5.95 |
| 2026-08-12 12:00 |
01:49:06.30 |
-44:09:16.7 |
HIP 8477 |
5.54 |
| 2026-08-13 00:00 |
01:49:03.49 |
-44:10:59.2 |
HIP 8477 |
4.25 |
| 2026-08-13 12:00 |
01:49:00.57 |
-44:12:41.7 |
HIP 8477 |
3.44 |
| 2026-08-14 00:00 |
01:48:57.56 |
-44:14:24.1 |
HIP 8477 |
3.48 |
| 2026-08-14 12:00 |
01:48:54.44 |
-44:16:06.4 |
HIP 8477 |
4.35 |
| 2026-08-15 00:00 |
01:48:51.21 |
-44:17:48.6 |
HIP 8477 |
5.69 |
| 2026-08-15 12:00 |
01:48:47.89 |
-44:19:30.7 |
HIP 8391 |
5.98 |
| 2026-08-16 00:00 |
01:48:44.47 |
-44:21:12.6 |
HIP 8391 |
5.49 |
| 2026-08-16 12:00 |
01:48:40.94 |
-44:22:54.4 |
HIP 8391 |
5.56 |
| 2026-08-17 00:00 |
01:48:37.31 |
-44:24:36.0 |
HIP 8391 |
6.18 |
| 2026-08-17 12:00 |
01:48:33.58 |
-44:26:17.5 |
HIP 8391 |
7.19 |
| 2026-08-18 00:00 |
01:48:29.75 |
-44:27:58.8 |
HIP 8391 |
8.47 |
| 2026-08-18 12:00 |
01:48:25.82 |
-44:29:40.0 |
HIP 8391 |
9.92 |
| 2026-08-19 00:00 |
01:48:21.79 |
-44:31:20.9 |
HIP 8391 |
11.47 |