메타데이터
| 항목 |
값 |
| Designation |
C/1921 E1 (Reid) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1921-05-10T10:47:48.370560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:02Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
1921-04-10.0000000 |
| e |
1.00057570 |
| q (au) |
1.008454 |
| a (au) |
-1751.685065 |
| i (deg) |
132.188784 |
| Ω (om, deg) |
269.441203 |
| ω (w, deg) |
64.493054 |
| M (ma, deg) |
-0.000409 |
밝기
산란 + 전체 선형
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-03-26 00:00 |
03:37:13.40 |
-18:25:01.7 |
HIP 16799 |
16.40 |
| 2026-03-26 12:00 |
03:37:13.99 |
-18:24:53.4 |
HIP 16799 |
16.59 |
| 2026-03-27 00:00 |
03:37:14.58 |
-18:24:45.1 |
HIP 16799 |
16.78 |
| 2026-03-27 12:00 |
03:37:15.18 |
-18:24:36.8 |
HIP 16799 |
16.97 |
| 2026-03-28 00:00 |
03:37:15.78 |
-18:24:28.6 |
HIP 16799 |
17.17 |
| 2026-03-28 12:00 |
03:37:16.39 |
-18:24:20.4 |
HIP 16799 |
17.36 |
| 2026-03-29 00:00 |
03:37:17.01 |
-18:24:12.2 |
HIP 16799 |
17.55 |
| 2026-03-29 12:00 |
03:37:17.63 |
-18:24:04.1 |
HIP 16799 |
17.75 |
| 2026-03-30 00:00 |
03:37:18.26 |
-18:23:56.0 |
HIP 16799 |
17.95 |
| 2026-03-30 12:00 |
03:37:18.90 |
-18:23:47.9 |
HIP 16799 |
18.15 |
| 2026-03-31 00:00 |
03:37:19.54 |
-18:23:39.9 |
HIP 16799 |
18.35 |
| 2026-03-31 12:00 |
03:37:20.19 |
-18:23:31.9 |
HIP 16799 |
18.55 |
| 2026-04-01 00:00 |
03:37:20.84 |
-18:23:23.9 |
HIP 16799 |
18.75 |
| 2026-04-01 12:00 |
03:37:21.50 |
-18:23:16.0 |
HIP 16799 |
18.95 |
| 2026-04-02 00:00 |
03:37:22.17 |
-18:23:08.1 |
HIP 16799 |
19.15 |
| 2026-04-02 12:00 |
03:37:22.84 |
-18:23:00.2 |
HIP 16799 |
19.36 |
| 2026-04-03 00:00 |
03:37:23.51 |
-18:22:52.4 |
HIP 16799 |
19.56 |
| 2026-04-03 12:00 |
03:37:24.19 |
-18:22:44.6 |
HIP 16799 |
19.77 |
| 2026-04-04 00:00 |
03:37:24.88 |
-18:22:36.9 |
HIP 16799 |
19.97 |
| 2026-04-04 12:00 |
03:37:25.58 |
-18:22:29.2 |
HIP 16799 |
20.18 |
| 2026-04-05 00:00 |
03:37:26.27 |
-18:22:21.6 |
HIP 16799 |
20.39 |
| 2026-04-05 12:00 |
03:37:26.98 |
-18:22:13.9 |
HIP 16799 |
20.60 |
| 2026-04-06 00:00 |
03:37:27.69 |
-18:22:06.4 |
HIP 16799 |
20.81 |
| 2026-04-06 12:00 |
03:37:28.40 |
-18:21:58.8 |
HIP 16799 |
21.02 |
| 2026-04-07 00:00 |
03:37:29.12 |
-18:21:51.3 |
HIP 16799 |
21.23 |
| 2026-04-07 12:00 |
03:37:29.85 |
-18:21:43.9 |
HIP 16799 |
21.44 |
| 2026-04-08 00:00 |
03:37:30.58 |
-18:21:36.5 |
HIP 16799 |
21.65 |
| 2026-04-08 12:00 |
03:37:31.31 |
-18:21:29.1 |
HIP 16799 |
21.86 |
| 2026-04-09 00:00 |
03:37:32.05 |
-18:21:21.8 |
HIP 16799 |
22.08 |
| 2026-04-09 12:00 |
03:37:32.80 |
-18:21:14.5 |
HIP 16799 |
22.29 |
| 2026-04-10 00:00 |
03:37:33.55 |
-18:21:07.3 |
HIP 16799 |
22.51 |
| 2026-04-10 12:00 |
03:37:34.31 |
-18:21:00.1 |
HIP 16799 |
22.72 |
| 2026-04-11 00:00 |
03:37:35.07 |
-18:20:53.0 |
HIP 16799 |
22.94 |
| 2026-04-11 12:00 |
03:37:35.83 |
-18:20:45.9 |
HIP 16799 |
23.16 |
| 2026-04-12 00:00 |
03:37:36.60 |
-18:20:38.8 |
HIP 16799 |
23.37 |
| 2026-04-12 12:00 |
03:37:37.38 |
-18:20:31.9 |
HIP 16799 |
23.59 |
| 2026-04-13 00:00 |
03:37:38.16 |
-18:20:24.9 |
HIP 16799 |
23.81 |
| 2026-04-13 12:00 |
03:37:38.94 |
-18:20:18.0 |
HIP 16799 |
24.03 |
| 2026-04-14 00:00 |
03:37:39.73 |
-18:20:11.2 |
HIP 16799 |
24.25 |
| 2026-04-14 12:00 |
03:37:40.52 |
-18:20:04.4 |
HIP 16799 |
24.47 |
| 2026-04-15 00:00 |
03:37:41.32 |
-18:19:57.6 |
HIP 16799 |
24.69 |
| 2026-04-15 12:00 |
03:37:42.12 |
-18:19:50.9 |
HIP 16799 |
24.91 |
| 2026-04-16 00:00 |
03:37:42.93 |
-18:19:44.3 |
HIP 16799 |
25.13 |