메타데이터
| 항목 |
값 |
| Designation |
C/1987 W1 (Ichimura) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1988-01-10T02:29:58.758720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:36Z |
| Obs used |
48 |
| NEO |
- |
| M1 |
8.900 |
| K1 |
10.000 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
1987-11-28.0000000 |
| e |
0.99999939 |
| q (au) |
0.199518 |
| a (au) |
327902.551553 |
| i (deg) |
41.620500 |
| Ω (om, deg) |
226.527901 |
| ω (w, deg) |
329.292632 |
| M (ma, deg) |
360.000000 |
밝기
산란 + 전체 선형
$$
M_a = (10.506 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.506 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
0.843 |
| δ90 |
1.000 |
| 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) |
| 2026-05-12 00:00 |
00:25:16.42 |
+28:14:06.9 |
HIP 1990 |
9.55 |
| 2026-05-12 12:00 |
00:25:17.81 |
+28:14:22.0 |
HIP 1990 |
9.84 |
| 2026-05-13 00:00 |
00:25:19.19 |
+28:14:37.1 |
HIP 1990 |
10.14 |
| 2026-05-13 12:00 |
00:25:20.56 |
+28:14:52.2 |
HIP 1990 |
10.45 |
| 2026-05-14 00:00 |
00:25:21.92 |
+28:15:07.4 |
HIP 1990 |
10.76 |
| 2026-05-14 12:00 |
00:25:23.27 |
+28:15:22.6 |
HIP 1990 |
11.07 |
| 2026-05-15 00:00 |
00:25:24.60 |
+28:15:37.7 |
HIP 1990 |
11.39 |
| 2026-05-15 12:00 |
00:25:25.93 |
+28:15:52.9 |
HIP 1990 |
11.71 |
| 2026-05-16 00:00 |
00:25:27.24 |
+28:16:08.1 |
HIP 1990 |
12.04 |
| 2026-05-16 12:00 |
00:25:28.54 |
+28:16:23.3 |
HIP 1990 |
12.37 |
| 2026-05-17 00:00 |
00:25:29.83 |
+28:16:38.5 |
HIP 1990 |
12.70 |
| 2026-05-17 12:00 |
00:25:31.11 |
+28:16:53.7 |
HIP 1990 |
13.03 |
| 2026-05-18 00:00 |
00:25:32.37 |
+28:17:09.0 |
HIP 1990 |
13.37 |
| 2026-05-18 12:00 |
00:25:33.62 |
+28:17:24.2 |
HIP 1990 |
13.70 |
| 2026-05-19 00:00 |
00:25:34.87 |
+28:17:39.4 |
HIP 1990 |
14.04 |
| 2026-05-19 12:00 |
00:25:36.09 |
+28:17:54.6 |
HIP 1990 |
14.38 |
| 2026-05-20 00:00 |
00:25:37.31 |
+28:18:09.8 |
HIP 1990 |
14.71 |
| 2026-05-20 12:00 |
00:25:38.51 |
+28:18:25.0 |
HIP 1990 |
15.05 |
| 2026-05-21 00:00 |
00:25:39.70 |
+28:18:40.2 |
HIP 1990 |
15.39 |
| 2026-05-21 12:00 |
00:25:40.88 |
+28:18:55.4 |
HIP 1990 |
15.73 |
| 2026-05-22 00:00 |
00:25:42.05 |
+28:19:10.6 |
HIP 1990 |
16.07 |
| 2026-05-22 12:00 |
00:25:43.20 |
+28:19:25.8 |
HIP 1990 |
16.40 |
| 2026-05-23 00:00 |
00:25:44.34 |
+28:19:41.0 |
HIP 1990 |
16.74 |
| 2026-05-23 12:00 |
00:25:45.47 |
+28:19:56.2 |
HIP 1990 |
17.08 |
| 2026-05-24 00:00 |
00:25:46.58 |
+28:20:11.3 |
HIP 1990 |
17.41 |
| 2026-05-24 12:00 |
00:25:47.68 |
+28:20:26.5 |
HIP 1990 |
17.75 |
| 2026-05-25 00:00 |
00:25:48.77 |
+28:20:41.6 |
HIP 1990 |
18.08 |
| 2026-05-25 12:00 |
00:25:49.84 |
+28:20:56.8 |
HIP 1990 |
18.42 |
| 2026-05-26 00:00 |
00:25:50.90 |
+28:21:11.9 |
HIP 1990 |
18.75 |
| 2026-05-26 12:00 |
00:25:51.95 |
+28:21:27.0 |
HIP 1990 |
19.08 |
| 2026-05-27 00:00 |
00:25:52.98 |
+28:21:42.1 |
HIP 1990 |
19.41 |
| 2026-05-27 12:00 |
00:25:54.00 |
+28:21:57.1 |
HIP 1990 |
19.74 |
| 2026-05-28 00:00 |
00:25:55.01 |
+28:22:12.2 |
HIP 1990 |
20.06 |
| 2026-05-28 12:00 |
00:25:56.00 |
+28:22:27.2 |
HIP 1990 |
20.39 |
| 2026-05-29 00:00 |
00:25:56.98 |
+28:22:42.2 |
HIP 1990 |
20.71 |
| 2026-05-29 12:00 |
00:25:57.95 |
+28:22:57.2 |
HIP 1990 |
21.03 |
| 2026-05-30 00:00 |
00:25:58.90 |
+28:23:12.2 |
HIP 1990 |
21.35 |
| 2026-05-30 12:00 |
00:25:59.84 |
+28:23:27.1 |
HIP 1990 |
21.67 |
| 2026-05-31 00:00 |
00:26:00.77 |
+28:23:42.0 |
HIP 1990 |
21.99 |
| 2026-05-31 12:00 |
00:26:01.68 |
+28:23:56.9 |
HIP 1990 |
22.30 |
| 2026-06-01 00:00 |
00:26:02.57 |
+28:24:11.8 |
HIP 1990 |
22.62 |
| 2026-06-01 12:00 |
00:26:03.45 |
+28:24:26.7 |
HIP 1990 |
22.93 |
| 2026-06-02 00:00 |
00:26:04.32 |
+28:24:41.5 |
HIP 1990 |
23.24 |