메타데이터
| 항목 |
값 |
| Designation |
C/1919 Q2 (Metcalf) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1919-12-07T19:37:10.358400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:02Z |
| Obs used |
18 |
| NEO |
- |
| M1 |
5.100 |
| K1 |
11.500 |
| PC |
- |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
1919-09-18.0000000 |
| e |
0.99977859 |
| q (au) |
1.115204 |
| a (au) |
5036.797426 |
| i (deg) |
46.383158 |
| Ω (om, deg) |
122.097279 |
| ω (w, deg) |
185.764445 |
| M (ma, deg) |
359.999777 |
밝기
산란 + 전체 선형
$$
M_a = (6.671 + 5.125\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
6.671 |
| n |
5.125 |
| gf |
0.999 |
| gb |
-1.000 |
| 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) |
| 2026-03-26 00:00 |
07:58:11.35 |
+16:59:29.3 |
HIP 39046 |
18.95 |
| 2026-03-26 12:00 |
07:58:10.98 |
+16:59:31.3 |
HIP 39046 |
19.04 |
| 2026-03-27 00:00 |
07:58:10.61 |
+16:59:33.4 |
HIP 39046 |
19.13 |
| 2026-03-27 12:00 |
07:58:10.25 |
+16:59:35.4 |
HIP 39046 |
19.22 |
| 2026-03-28 00:00 |
07:58:09.90 |
+16:59:37.4 |
HIP 39046 |
19.31 |
| 2026-03-28 12:00 |
07:58:09.56 |
+16:59:39.3 |
HIP 39046 |
19.40 |
| 2026-03-29 00:00 |
07:58:09.23 |
+16:59:41.3 |
HIP 39046 |
19.48 |
| 2026-03-29 12:00 |
07:58:08.90 |
+16:59:43.2 |
HIP 39046 |
19.57 |
| 2026-03-30 00:00 |
07:58:08.58 |
+16:59:45.1 |
HIP 39046 |
19.65 |
| 2026-03-30 12:00 |
07:58:08.27 |
+16:59:47.0 |
HIP 39046 |
19.73 |
| 2026-03-31 00:00 |
07:58:07.97 |
+16:59:48.8 |
HIP 39046 |
19.81 |
| 2026-03-31 12:00 |
07:58:07.67 |
+16:59:50.6 |
HIP 39046 |
19.88 |
| 2026-04-01 00:00 |
07:58:07.39 |
+16:59:52.5 |
HIP 39046 |
19.96 |
| 2026-04-01 12:00 |
07:58:07.11 |
+16:59:54.3 |
HIP 39046 |
20.03 |
| 2026-04-02 00:00 |
07:58:06.84 |
+16:59:56.0 |
HIP 39046 |
20.10 |
| 2026-04-02 12:00 |
07:58:06.58 |
+16:59:57.8 |
HIP 39046 |
20.17 |
| 2026-04-03 00:00 |
07:58:06.32 |
+16:59:59.5 |
HIP 39046 |
20.23 |
| 2026-04-03 12:00 |
07:58:06.08 |
+17:00:01.2 |
HIP 39046 |
20.30 |
| 2026-04-04 00:00 |
07:58:05.84 |
+17:00:02.9 |
HIP 39046 |
20.36 |
| 2026-04-04 12:00 |
07:58:05.61 |
+17:00:04.6 |
HIP 39046 |
20.42 |
| 2026-04-05 00:00 |
07:58:05.39 |
+17:00:06.2 |
HIP 39046 |
20.48 |
| 2026-04-05 12:00 |
07:58:05.17 |
+17:00:07.9 |
HIP 39046 |
20.54 |
| 2026-04-06 00:00 |
07:58:04.97 |
+17:00:09.5 |
HIP 39046 |
20.60 |
| 2026-04-06 12:00 |
07:58:04.77 |
+17:00:11.0 |
HIP 39046 |
20.65 |
| 2026-04-07 00:00 |
07:58:04.58 |
+17:00:12.6 |
HIP 39046 |
20.70 |
| 2026-04-07 12:00 |
07:58:04.40 |
+17:00:14.1 |
HIP 39046 |
20.75 |
| 2026-04-08 00:00 |
07:58:04.23 |
+17:00:15.6 |
HIP 39046 |
20.80 |
| 2026-04-08 12:00 |
07:58:04.07 |
+17:00:17.1 |
HIP 39046 |
20.85 |
| 2026-04-09 00:00 |
07:58:03.91 |
+17:00:18.6 |
HIP 39046 |
20.89 |
| 2026-04-09 12:00 |
07:58:03.76 |
+17:00:20.0 |
HIP 39046 |
20.93 |
| 2026-04-10 00:00 |
07:58:03.62 |
+17:00:21.5 |
HIP 39046 |
20.97 |
| 2026-04-10 12:00 |
07:58:03.49 |
+17:00:22.9 |
HIP 39046 |
21.01 |
| 2026-04-11 00:00 |
07:58:03.37 |
+17:00:24.3 |
HIP 39046 |
21.05 |
| 2026-04-11 12:00 |
07:58:03.25 |
+17:00:25.6 |
HIP 39046 |
21.09 |
| 2026-04-12 00:00 |
07:58:03.15 |
+17:00:26.9 |
HIP 39046 |
21.12 |
| 2026-04-12 12:00 |
07:58:03.05 |
+17:00:28.2 |
HIP 39046 |
21.15 |
| 2026-04-13 00:00 |
07:58:02.96 |
+17:00:29.5 |
HIP 39046 |
21.18 |
| 2026-04-13 12:00 |
07:58:02.88 |
+17:00:30.8 |
HIP 39046 |
21.21 |
| 2026-04-14 00:00 |
07:58:02.81 |
+17:00:32.0 |
HIP 39046 |
21.23 |
| 2026-04-14 12:00 |
07:58:02.74 |
+17:00:33.2 |
HIP 39046 |
21.26 |
| 2026-04-15 00:00 |
07:58:02.69 |
+17:00:34.4 |
HIP 39046 |
21.28 |
| 2026-04-15 12:00 |
07:58:02.64 |
+17:00:35.6 |
HIP 39046 |
21.30 |
| 2026-04-16 00:00 |
07:58:02.60 |
+17:00:36.8 |
HIP 39046 |
21.32 |