메타데이터
| 항목 |
값 |
| Designation |
C/2017 C1 (NEOWISE) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-01-18T22:42:46.506240Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:29Z |
| Obs used |
60 |
| NEO |
- |
| M1 |
18.100 |
| K1 |
8.500 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-03-06.0000000 |
| e |
0.92781552 |
| q (au) |
1.501755 |
| a (au) |
20.804403 |
| i (deg) |
65.752241 |
| Ω (om, deg) |
357.457191 |
| ω (w, deg) |
110.204316 |
| M (ma, deg) |
0.478338 |
밝기
산란 + 전체 선형
$$
M_a = (17.436 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
17.436 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.703 |
| 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
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
12:23:04.62 |
-84:21:29.1 |
HIP 59928 |
9.13 |
| 2026-09-20 12:00 |
12:23:57.78 |
-84:21:29.1 |
HIP 59928 |
10.32 |
| 2026-09-21 00:00 |
12:24:50.99 |
-84:21:29.4 |
HIP 59928 |
11.54 |
| 2026-09-21 12:00 |
12:25:44.25 |
-84:21:30.2 |
HIP 59928 |
12.79 |
| 2026-09-22 00:00 |
12:26:37.55 |
-84:21:31.5 |
HIP 59928 |
14.05 |
| 2026-09-22 12:00 |
12:27:30.89 |
-84:21:33.1 |
HIP 61501 |
13.70 |
| 2026-09-23 00:00 |
12:28:24.29 |
-84:21:35.1 |
HIP 61501 |
12.49 |
| 2026-09-23 12:00 |
12:29:17.73 |
-84:21:37.6 |
HIP 61501 |
11.31 |
| 2026-09-24 00:00 |
12:30:11.22 |
-84:21:40.4 |
HIP 61501 |
10.18 |
| 2026-09-24 12:00 |
12:31:04.75 |
-84:21:43.7 |
HIP 61501 |
9.09 |
| 2026-09-25 00:00 |
12:31:58.34 |
-84:21:47.4 |
HIP 61501 |
8.09 |
| 2026-09-25 12:00 |
12:32:51.97 |
-84:21:51.5 |
HIP 61501 |
7.19 |
| 2026-09-26 00:00 |
12:33:45.65 |
-84:21:56.0 |
HIP 61501 |
6.44 |
| 2026-09-26 12:00 |
12:34:39.39 |
-84:22:00.9 |
HIP 61501 |
5.92 |
| 2026-09-27 00:00 |
12:35:33.17 |
-84:22:06.2 |
HIP 61501 |
5.67 |
| 2026-09-27 12:00 |
12:36:27.01 |
-84:22:11.9 |
HIP 61501 |
5.74 |
| 2026-09-28 00:00 |
12:37:20.89 |
-84:22:18.0 |
HIP 61501 |
6.11 |
| 2026-09-28 12:00 |
12:38:14.83 |
-84:22:24.5 |
HIP 61501 |
6.74 |
| 2026-09-29 00:00 |
12:39:08.82 |
-84:22:31.4 |
HIP 61501 |
7.56 |
| 2026-09-29 12:00 |
12:40:02.87 |
-84:22:38.7 |
HIP 61501 |
8.51 |
| 2026-09-30 00:00 |
12:40:56.96 |
-84:22:46.4 |
HIP 61501 |
9.57 |
| 2026-09-30 12:00 |
12:41:51.12 |
-84:22:54.6 |
HIP 61501 |
10.69 |
| 2026-10-01 00:00 |
12:42:45.32 |
-84:23:03.1 |
HIP 61501 |
11.87 |
| 2026-10-01 12:00 |
12:43:39.58 |
-84:23:12.0 |
HIP 61501 |
13.08 |
| 2026-10-02 00:00 |
12:44:33.90 |
-84:23:21.3 |
HIP 61501 |
14.32 |
| 2026-10-02 12:00 |
12:45:28.28 |
-84:23:31.0 |
HIP 61501 |
15.58 |
| 2026-10-03 00:00 |
12:46:22.71 |
-84:23:41.2 |
HIP 61501 |
16.86 |
| 2026-10-03 12:00 |
12:47:17.20 |
-84:23:51.7 |
HIP 61501 |
18.15 |
| 2026-10-04 00:00 |
12:48:11.74 |
-84:24:02.6 |
HIP 61501 |
19.45 |
| 2026-10-04 12:00 |
12:49:06.35 |
-84:24:13.9 |
HIP 61501 |
20.76 |
| 2026-10-05 00:00 |
12:50:01.01 |
-84:24:25.6 |
HIP 61501 |
22.08 |
| 2026-10-05 12:00 |
12:50:55.73 |
-84:24:37.7 |
HIP 61501 |
23.41 |
| 2026-10-06 00:00 |
12:51:50.51 |
-84:24:50.2 |
HIP 61501 |
24.74 |
| 2026-10-06 12:00 |
12:52:45.35 |
-84:25:03.1 |
HIP 61501 |
26.08 |
| 2026-10-07 00:00 |
12:53:40.24 |
-84:25:16.4 |
HIP 61501 |
27.42 |
| 2026-10-07 12:00 |
12:54:35.20 |
-84:25:30.1 |
HIP 61501 |
28.77 |
| 2026-10-08 00:00 |
12:55:30.21 |
-84:25:44.2 |
HIP 64743 |
30.04 |
| 2026-10-08 12:00 |
12:56:25.29 |
-84:25:58.6 |
HIP 64743 |
28.68 |
| 2026-10-09 00:00 |
12:57:20.42 |
-84:26:13.5 |
HIP 64743 |
27.33 |
| 2026-10-09 12:00 |
12:58:15.61 |
-84:26:28.8 |
HIP 64743 |
25.97 |
| 2026-10-10 00:00 |
12:59:10.86 |
-84:26:44.4 |
HIP 64743 |
24.62 |
| 2026-10-10 12:00 |
13:00:06.17 |
-84:27:00.4 |
HIP 64743 |
23.27 |
| 2026-10-11 00:00 |
13:01:01.55 |
-84:27:16.9 |
HIP 64743 |
21.91 |