메타데이터
| 항목 |
값 |
| Designation |
21P/Giacobini-Zinner |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-09-10T06:22:53.924160Z |
| Orbit solution date (soln_date, UTC) |
2025-11-23T22:20:59Z |
| Obs used |
1993 |
| NEO |
Yes |
| M1 |
13.200 |
| K1 |
8.250 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2017-11-13.0000000 |
| e |
0.71047048 |
| q (au) |
1.013441 |
| a (au) |
3.500303 |
| i (deg) |
32.002592 |
| Ω (om, deg) |
195.404480 |
| ω (w, deg) |
172.812482 |
| M (ma, deg) |
314.658527 |
밝기
산란 + 전체 선형
$$
M_a = (10.463 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.463 |
| n |
6.000 |
| gf |
0.882 |
| gb |
-0.912 |
| k |
1.000 |
| δ90 |
9.999 |
| 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
찾아보기
천체력
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
09:03:57.73 |
-06:30:58.1 |
HIP 44454 |
35.67 |
| 2026-05-12 12:00 |
09:04:13.24 |
-06:28:24.5 |
HIP 44454 |
34.39 |
| 2026-05-13 00:00 |
09:04:28.91 |
-06:25:52.8 |
HIP 44454 |
33.74 |
| 2026-05-13 12:00 |
09:04:44.74 |
-06:23:23.1 |
HIP 44454 |
33.78 |
| 2026-05-14 00:00 |
09:05:00.72 |
-06:20:55.2 |
HIP 44454 |
34.51 |
| 2026-05-14 12:00 |
09:05:16.87 |
-06:18:29.3 |
HIP 44454 |
35.88 |
| 2026-05-15 00:00 |
09:05:33.16 |
-06:16:05.3 |
HIP 44454 |
37.84 |
| 2026-05-15 12:00 |
09:05:49.61 |
-06:13:43.3 |
HIP 44454 |
40.31 |
| 2026-05-16 00:00 |
09:06:06.20 |
-06:11:23.1 |
HIP 44454 |
43.20 |
| 2026-05-16 12:00 |
09:06:22.95 |
-06:09:04.8 |
HIP 44922 |
41.62 |
| 2026-05-17 00:00 |
09:06:39.84 |
-06:06:48.5 |
HIP 44922 |
36.97 |
| 2026-05-17 12:00 |
09:06:56.89 |
-06:04:34.0 |
HIP 44922 |
32.34 |
| 2026-05-18 00:00 |
09:07:14.07 |
-06:02:21.4 |
HIP 44922 |
27.72 |
| 2026-05-18 12:00 |
09:07:31.40 |
-06:00:10.7 |
HIP 44922 |
23.15 |
| 2026-05-19 00:00 |
09:07:48.87 |
-05:58:01.9 |
HIP 44922 |
18.67 |
| 2026-05-19 12:00 |
09:08:06.48 |
-05:55:55.0 |
HIP 44922 |
14.40 |
| 2026-05-20 00:00 |
09:08:24.23 |
-05:53:49.9 |
HIP 44922 |
10.60 |
| 2026-05-20 12:00 |
09:08:42.12 |
-05:51:46.7 |
HIP 44922 |
8.02 |
| 2026-05-21 00:00 |
09:09:00.14 |
-05:49:45.4 |
HIP 44922 |
7.98 |
| 2026-05-21 12:00 |
09:09:18.29 |
-05:47:45.9 |
HIP 44922 |
10.54 |
| 2026-05-22 00:00 |
09:09:36.58 |
-05:45:48.2 |
HIP 44922 |
14.38 |
| 2026-05-22 12:00 |
09:09:55.00 |
-05:43:52.4 |
HIP 44922 |
18.75 |
| 2026-05-23 00:00 |
09:10:13.54 |
-05:41:58.4 |
HIP 44922 |
23.37 |
| 2026-05-23 12:00 |
09:10:32.22 |
-05:40:06.3 |
HIP 44922 |
28.12 |
| 2026-05-24 00:00 |
09:10:51.02 |
-05:38:15.9 |
HIP 45034 |
32.20 |
| 2026-05-24 12:00 |
09:11:09.95 |
-05:36:27.4 |
HIP 45034 |
35.30 |
| 2026-05-25 00:00 |
09:11:29.00 |
-05:34:40.6 |
HIP 45262 |
33.58 |
| 2026-05-25 12:00 |
09:11:48.17 |
-05:32:55.7 |
HIP 45262 |
30.25 |
| 2026-05-26 00:00 |
09:12:07.46 |
-05:31:12.5 |
HIP 45262 |
27.42 |
| 2026-05-26 12:00 |
09:12:26.87 |
-05:29:31.1 |
HIP 45262 |
25.27 |
| 2026-05-27 00:00 |
09:12:46.40 |
-05:27:51.5 |
HIP 45262 |
24.00 |
| 2026-05-27 12:00 |
09:13:06.04 |
-05:26:13.6 |
HIP 45352 |
21.61 |
| 2026-05-28 00:00 |
09:13:25.80 |
-05:24:37.5 |
HIP 45352 |
17.19 |
| 2026-05-28 12:00 |
09:13:45.67 |
-05:23:03.1 |
HIP 45352 |
13.29 |
| 2026-05-29 00:00 |
09:14:05.66 |
-05:21:30.5 |
HIP 45352 |
10.52 |
| 2026-05-29 12:00 |
09:14:25.75 |
-05:19:59.5 |
HIP 45352 |
9.91 |
| 2026-05-30 00:00 |
09:14:45.96 |
-05:18:30.3 |
HIP 45352 |
11.84 |
| 2026-05-30 12:00 |
09:15:06.28 |
-05:17:02.9 |
HIP 45352 |
15.38 |
| 2026-05-31 00:00 |
09:15:26.70 |
-05:15:37.1 |
HIP 45352 |
19.71 |
| 2026-05-31 12:00 |
09:15:47.23 |
-05:14:13.0 |
HIP 45489 |
22.82 |
| 2026-06-01 00:00 |
09:16:07.86 |
-05:12:50.6 |
HIP 45489 |
20.83 |
| 2026-06-01 12:00 |
09:16:28.60 |
-05:11:29.9 |
HIP 45489 |
20.13 |
| 2026-06-02 00:00 |
09:16:49.44 |
-05:10:10.9 |
HIP 45489 |
20.85 |