메타데이터
| 항목 |
값 |
| Designation |
P/2017 D4 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-09-06T15:17:49.675200Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:43:23Z |
| Obs used |
91 |
| NEO |
- |
| M1 |
16.300 |
| K1 |
4.500 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-03-06.0000000 |
| e |
0.62891585 |
| q (au) |
2.754615 |
| a (au) |
7.423156 |
| i (deg) |
10.339594 |
| Ω (om, deg) |
266.104140 |
| ω (w, deg) |
209.796281 |
| M (ma, deg) |
8.789572 |
밝기
산란 + 전체 선형
$$
M_a = (15.387 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
15.387 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-1.000 |
| 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 |
19:36:07.31 |
-15:51:52.2 |
HIP 96389 |
18.79 |
| 2026-07-29 12:00 |
19:35:58.84 |
-15:52:11.4 |
HIP 96389 |
18.75 |
| 2026-07-30 00:00 |
19:35:50.39 |
-15:52:30.6 |
HIP 96389 |
18.94 |
| 2026-07-30 12:00 |
19:35:41.96 |
-15:52:49.9 |
HIP 96389 |
19.34 |
| 2026-07-31 00:00 |
19:35:33.56 |
-15:53:09.2 |
HIP 96389 |
19.95 |
| 2026-07-31 12:00 |
19:35:25.19 |
-15:53:28.6 |
HIP 96389 |
20.74 |
| 2026-08-01 00:00 |
19:35:16.84 |
-15:53:48.0 |
HIP 96212 |
21.22 |
| 2026-08-01 12:00 |
19:35:08.52 |
-15:54:07.4 |
HIP 96212 |
19.34 |
| 2026-08-02 00:00 |
19:35:00.23 |
-15:54:26.9 |
HIP 96212 |
17.50 |
| 2026-08-02 12:00 |
19:34:51.97 |
-15:54:46.4 |
HIP 96212 |
15.72 |
| 2026-08-03 00:00 |
19:34:43.74 |
-15:55:05.9 |
HIP 96212 |
14.00 |
| 2026-08-03 12:00 |
19:34:35.54 |
-15:55:25.5 |
HIP 96212 |
12.37 |
| 2026-08-04 00:00 |
19:34:27.38 |
-15:55:45.1 |
HIP 96212 |
10.88 |
| 2026-08-04 12:00 |
19:34:19.24 |
-15:56:04.7 |
HIP 96212 |
9.58 |
| 2026-08-05 00:00 |
19:34:11.14 |
-15:56:24.4 |
HIP 96212 |
8.54 |
| 2026-08-05 12:00 |
19:34:03.08 |
-15:56:44.0 |
HIP 96212 |
7.88 |
| 2026-08-06 00:00 |
19:33:55.05 |
-15:57:03.7 |
HIP 96212 |
7.68 |
| 2026-08-06 12:00 |
19:33:47.05 |
-15:57:23.5 |
HIP 96212 |
7.98 |
| 2026-08-07 00:00 |
19:33:39.10 |
-15:57:43.2 |
HIP 96212 |
8.70 |
| 2026-08-07 12:00 |
19:33:31.18 |
-15:58:02.9 |
HIP 96212 |
9.76 |
| 2026-08-08 00:00 |
19:33:23.30 |
-15:58:22.7 |
HIP 96212 |
11.06 |
| 2026-08-08 12:00 |
19:33:15.46 |
-15:58:42.5 |
HIP 96212 |
12.51 |
| 2026-08-09 00:00 |
19:33:07.66 |
-15:59:02.2 |
HIP 96212 |
14.06 |
| 2026-08-09 12:00 |
19:32:59.90 |
-15:59:22.0 |
HIP 96212 |
15.68 |
| 2026-08-10 00:00 |
19:32:52.18 |
-15:59:41.8 |
HIP 96109 |
15.90 |
| 2026-08-10 12:00 |
19:32:44.51 |
-16:00:01.6 |
HIP 96109 |
15.58 |
| 2026-08-11 00:00 |
19:32:36.88 |
-16:00:21.4 |
HIP 96109 |
15.49 |
| 2026-08-11 12:00 |
19:32:29.30 |
-16:00:41.2 |
HIP 96109 |
15.61 |
| 2026-08-12 00:00 |
19:32:21.76 |
-16:01:01.0 |
HIP 96109 |
15.96 |
| 2026-08-12 12:00 |
19:32:14.26 |
-16:01:20.7 |
HIP 96109 |
16.50 |
| 2026-08-13 00:00 |
19:32:06.82 |
-16:01:40.5 |
HIP 96109 |
17.21 |
| 2026-08-13 12:00 |
19:31:59.42 |
-16:02:00.3 |
HIP 96109 |
18.08 |
| 2026-08-14 00:00 |
19:31:52.07 |
-16:02:20.0 |
HIP 95952 |
17.47 |
| 2026-08-14 12:00 |
19:31:44.77 |
-16:02:39.7 |
HIP 95952 |
15.76 |
| 2026-08-15 00:00 |
19:31:37.52 |
-16:02:59.4 |
HIP 95952 |
14.07 |
| 2026-08-15 12:00 |
19:31:30.33 |
-16:03:19.1 |
HIP 95952 |
12.42 |
| 2026-08-16 00:00 |
19:31:23.18 |
-16:03:38.7 |
HIP 95952 |
10.82 |
| 2026-08-16 12:00 |
19:31:16.09 |
-16:03:58.4 |
HIP 95952 |
9.28 |
| 2026-08-17 00:00 |
19:31:09.05 |
-16:04:18.0 |
HIP 95952 |
7.83 |
| 2026-08-17 12:00 |
19:31:02.06 |
-16:04:37.5 |
HIP 95952 |
6.52 |
| 2026-08-18 00:00 |
19:30:55.13 |
-16:04:57.1 |
HIP 95952 |
5.44 |
| 2026-08-18 12:00 |
19:30:48.25 |
-16:05:16.6 |
HIP 95952 |
4.75 |
| 2026-08-19 00:00 |
19:30:41.43 |
-16:05:36.0 |
HIP 95952 |
4.59 |