메타데이터
| 항목 |
값 |
| Designation |
C/2017 X1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-06-14T10:45:05.999040Z |
| Orbit solution date (soln_date, UTC) |
2021-09-04T23:42:57Z |
| Obs used |
127 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
13.500 |
| PC |
0.030 |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2018-02-14.0000000 |
| e |
0.85110910 |
| q (au) |
4.662645 |
| a (au) |
31.315852 |
| i (deg) |
31.310998 |
| Ω (om, deg) |
251.126772 |
| ω (w, deg) |
283.106326 |
| M (ma, deg) |
359.322581 |
밝기
산란 + 전체 선형
$$
M_a = (5.561 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
5.561 |
| n |
6.000 |
| gf |
1.000 |
| 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
잔차 (구간 선형)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 시작일 (UTC) |
끝 (UTC) |
a |
b |
| 2017-02-12 |
2018-06-07 |
+17.3813 |
-12.086 |
| 2018-07-17 |
2019-07-25 |
-2.0175 |
+1.329 |
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 |
19:30:40.67 |
+03:01:18.0 |
HIP 95898 |
10.31 |
| 2026-07-29 12:00 |
19:30:34.92 |
+03:01:01.0 |
HIP 95898 |
9.11 |
| 2026-07-30 00:00 |
19:30:29.19 |
+03:00:43.7 |
HIP 95898 |
7.98 |
| 2026-07-30 12:00 |
19:30:23.48 |
+03:00:26.1 |
HIP 95898 |
6.98 |
| 2026-07-31 00:00 |
19:30:17.79 |
+03:00:08.1 |
HIP 95898 |
6.16 |
| 2026-07-31 12:00 |
19:30:12.12 |
+02:59:49.8 |
HIP 95898 |
5.60 |
| 2026-08-01 00:00 |
19:30:06.47 |
+02:59:31.2 |
HIP 95898 |
5.37 |
| 2026-08-01 12:00 |
19:30:00.84 |
+02:59:12.3 |
HIP 95898 |
5.52 |
| 2026-08-02 00:00 |
19:29:55.23 |
+02:58:53.0 |
HIP 95898 |
6.01 |
| 2026-08-02 12:00 |
19:29:49.65 |
+02:58:33.5 |
HIP 95898 |
6.77 |
| 2026-08-03 00:00 |
19:29:44.08 |
+02:58:13.6 |
HIP 95898 |
7.71 |
| 2026-08-03 12:00 |
19:29:38.54 |
+02:57:53.4 |
HIP 95834 |
7.79 |
| 2026-08-04 00:00 |
19:29:33.02 |
+02:57:33.0 |
HIP 95834 |
7.88 |
| 2026-08-04 12:00 |
19:29:27.52 |
+02:57:12.2 |
HIP 95834 |
8.22 |
| 2026-08-05 00:00 |
19:29:22.05 |
+02:56:51.1 |
HIP 95834 |
8.77 |
| 2026-08-05 12:00 |
19:29:16.60 |
+02:56:29.7 |
HIP 95834 |
9.51 |
| 2026-08-06 00:00 |
19:29:11.18 |
+02:56:08.0 |
HIP 95834 |
10.39 |
| 2026-08-06 12:00 |
19:29:05.79 |
+02:55:46.0 |
HIP 95732 |
11.23 |
| 2026-08-07 00:00 |
19:29:00.42 |
+02:55:23.8 |
HIP 95732 |
9.90 |
| 2026-08-07 12:00 |
19:28:55.07 |
+02:55:01.2 |
HIP 95732 |
8.59 |
| 2026-08-08 00:00 |
19:28:49.76 |
+02:54:38.3 |
HIP 95732 |
7.32 |
| 2026-08-08 12:00 |
19:28:44.47 |
+02:54:15.2 |
HIP 95732 |
6.11 |
| 2026-08-09 00:00 |
19:28:39.21 |
+02:53:51.8 |
HIP 95732 |
4.99 |
| 2026-08-09 12:00 |
19:28:33.98 |
+02:53:28.1 |
HIP 95732 |
4.04 |
| 2026-08-10 00:00 |
19:28:28.78 |
+02:53:04.1 |
HIP 95732 |
3.38 |
| 2026-08-10 12:00 |
19:28:23.61 |
+02:52:39.9 |
HIP 95732 |
3.22 |
| 2026-08-11 00:00 |
19:28:18.46 |
+02:52:15.4 |
HIP 95732 |
3.60 |
| 2026-08-11 12:00 |
19:28:13.35 |
+02:51:50.6 |
HIP 95732 |
4.38 |
| 2026-08-12 00:00 |
19:28:08.28 |
+02:51:25.5 |
HIP 95732 |
5.38 |
| 2026-08-12 12:00 |
19:28:03.23 |
+02:51:00.2 |
HIP 95732 |
6.50 |
| 2026-08-13 00:00 |
19:27:58.21 |
+02:50:34.7 |
HIP 95732 |
7.69 |
| 2026-08-13 12:00 |
19:27:53.23 |
+02:50:08.8 |
HIP 95732 |
8.91 |
| 2026-08-14 00:00 |
19:27:48.29 |
+02:49:42.8 |
HIP 95732 |
10.15 |
| 2026-08-14 12:00 |
19:27:43.37 |
+02:49:16.4 |
HIP 95732 |
11.40 |
| 2026-08-15 00:00 |
19:27:38.49 |
+02:48:49.9 |
HIP 95732 |
12.66 |
| 2026-08-15 12:00 |
19:27:33.65 |
+02:48:23.1 |
HIP 95732 |
13.92 |
| 2026-08-16 00:00 |
19:27:28.84 |
+02:47:56.0 |
HIP 95732 |
15.17 |
| 2026-08-16 12:00 |
19:27:24.07 |
+02:47:28.7 |
HIP 95732 |
16.43 |
| 2026-08-17 00:00 |
19:27:19.33 |
+02:47:01.2 |
HIP 95732 |
17.68 |
| 2026-08-17 12:00 |
19:27:14.63 |
+02:46:33.5 |
HIP 95732 |
18.93 |
| 2026-08-18 00:00 |
19:27:09.97 |
+02:46:05.5 |
HIP 95732 |
20.18 |
| 2026-08-18 12:00 |
19:27:05.35 |
+02:45:37.3 |
HIP 95732 |
21.42 |
| 2026-08-19 00:00 |
19:27:00.76 |
+02:45:08.9 |
HIP 95732 |
22.65 |