메타데이터
| 항목 |
값 |
| Designation |
C/2017 T2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-05-04T22:47:59.723520Z |
| Orbit solution date (soln_date, UTC) |
2026-07-28T14:12:17Z |
| Obs used |
6929 |
| NEO |
- |
| M1 |
10.200 |
| K1 |
4.500 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2019-12-14.0000000 |
| e |
0.99967660 |
| q (au) |
1.615096 |
| a (au) |
4994.082846 |
| i (deg) |
57.231424 |
| Ω (om, deg) |
64.378772 |
| ω (w, deg) |
92.993313 |
| M (ma, deg) |
359.999601 |
밝기
산란 + 전체 선형
$$
M_a = (10.827 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.827 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.653 |
| k |
0.800 |
| 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 |
| 2017-09-15 |
2019-08-05 |
+4.1328 |
-3.262 |
| 2019-08-05 |
2020-01-09 |
-1.8797 |
+0.423 |
| 2020-01-09 |
2020-05-04 |
+5.4565 |
-2.847 |
| 2020-05-05 |
2020-08-08 |
+15.7863 |
-4.493 |
| 2020-08-08 |
2021-10-04 |
+3.9198 |
-1.129 |
log10 r = log10(태양거리/AU), Δ = 지구거리(AU)
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
19:24:08.76 |
-68:48:36.7 |
HIP 95391 |
19.97 |
| 2026-09-20 12:00 |
19:24:03.95 |
-68:47:36.9 |
HIP 95391 |
20.99 |
| 2026-09-21 00:00 |
19:23:59.30 |
-68:46:36.9 |
HIP 95391 |
22.02 |
| 2026-09-21 12:00 |
19:23:54.80 |
-68:45:36.6 |
HIP 95391 |
23.05 |
| 2026-09-22 00:00 |
19:23:50.46 |
-68:44:36.1 |
HIP 95369 |
22.38 |
| 2026-09-22 12:00 |
19:23:46.27 |
-68:43:35.4 |
HIP 95369 |
21.40 |
| 2026-09-23 00:00 |
19:23:42.25 |
-68:42:34.3 |
HIP 95369 |
20.42 |
| 2026-09-23 12:00 |
19:23:38.37 |
-68:41:33.1 |
HIP 95369 |
19.45 |
| 2026-09-24 00:00 |
19:23:34.66 |
-68:40:31.6 |
HIP 95369 |
18.48 |
| 2026-09-24 12:00 |
19:23:31.10 |
-68:39:30.0 |
HIP 95369 |
17.52 |
| 2026-09-25 00:00 |
19:23:27.69 |
-68:38:28.1 |
HIP 95369 |
16.57 |
| 2026-09-25 12:00 |
19:23:24.44 |
-68:37:25.9 |
HIP 95369 |
15.63 |
| 2026-09-26 00:00 |
19:23:21.34 |
-68:36:23.6 |
HIP 95369 |
14.70 |
| 2026-09-26 12:00 |
19:23:18.40 |
-68:35:21.1 |
HIP 95369 |
13.78 |
| 2026-09-27 00:00 |
19:23:15.62 |
-68:34:18.4 |
HIP 95369 |
12.88 |
| 2026-09-27 12:00 |
19:23:12.99 |
-68:33:15.5 |
HIP 95369 |
12.00 |
| 2026-09-28 00:00 |
19:23:10.51 |
-68:32:12.4 |
HIP 95369 |
11.15 |
| 2026-09-28 12:00 |
19:23:08.19 |
-68:31:09.2 |
HIP 95369 |
10.33 |
| 2026-09-29 00:00 |
19:23:06.02 |
-68:30:05.8 |
HIP 95369 |
9.55 |
| 2026-09-29 12:00 |
19:23:04.01 |
-68:29:02.2 |
HIP 95369 |
8.82 |
| 2026-09-30 00:00 |
19:23:02.15 |
-68:27:58.4 |
HIP 95369 |
8.16 |
| 2026-09-30 12:00 |
19:23:00.44 |
-68:26:54.5 |
HIP 95369 |
7.58 |
| 2026-10-01 00:00 |
19:22:58.89 |
-68:25:50.4 |
HIP 95369 |
7.10 |
| 2026-10-01 12:00 |
19:22:57.49 |
-68:24:46.2 |
HIP 95369 |
6.75 |
| 2026-10-02 00:00 |
19:22:56.24 |
-68:23:41.9 |
HIP 95369 |
6.54 |
| 2026-10-02 12:00 |
19:22:55.15 |
-68:22:37.4 |
HIP 95369 |
6.49 |
| 2026-10-03 00:00 |
19:22:54.21 |
-68:21:32.8 |
HIP 95369 |
6.61 |
| 2026-10-03 12:00 |
19:22:53.42 |
-68:20:28.0 |
HIP 95369 |
6.89 |
| 2026-10-04 00:00 |
19:22:52.78 |
-68:19:23.1 |
HIP 95369 |
7.30 |
| 2026-10-04 12:00 |
19:22:52.30 |
-68:18:18.2 |
HIP 95369 |
7.83 |
| 2026-10-05 00:00 |
19:22:51.96 |
-68:17:13.1 |
HIP 95383 |
7.64 |
| 2026-10-05 12:00 |
19:22:51.78 |
-68:16:07.9 |
HIP 95383 |
7.49 |
| 2026-10-06 00:00 |
19:22:51.75 |
-68:15:02.6 |
HIP 95383 |
7.49 |
| 2026-10-06 12:00 |
19:22:51.87 |
-68:13:57.2 |
HIP 95383 |
7.63 |
| 2026-10-07 00:00 |
19:22:52.14 |
-68:12:51.7 |
HIP 95383 |
7.91 |
| 2026-10-07 12:00 |
19:22:52.56 |
-68:11:46.1 |
HIP 95383 |
8.31 |
| 2026-10-08 00:00 |
19:22:53.14 |
-68:10:40.5 |
HIP 95383 |
8.82 |
| 2026-10-08 12:00 |
19:22:53.86 |
-68:09:34.8 |
HIP 95383 |
9.42 |
| 2026-10-09 00:00 |
19:22:54.73 |
-68:08:29.0 |
HIP 95383 |
10.09 |
| 2026-10-09 12:00 |
19:22:55.75 |
-68:07:23.1 |
HIP 95383 |
10.82 |
| 2026-10-10 00:00 |
19:22:56.91 |
-68:06:17.2 |
HIP 95383 |
11.61 |
| 2026-10-10 12:00 |
19:22:58.23 |
-68:05:11.3 |
HIP 95383 |
12.43 |
| 2026-10-11 00:00 |
19:22:59.69 |
-68:04:05.3 |
HIP 95383 |
13.29 |