메타데이터
| 항목 |
값 |
| Designation |
C/2025 K4 (Siverd) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-07-28T06:25:56.997120Z |
| Orbit solution date (soln_date, UTC) |
2025-12-12T11:12:30Z |
| Obs used |
29 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-05-30T22:52:21.100800Z |
| Discovery magnitude (MPC) |
19.15 o |
| Discovery observatory (MPC) |
M22 · ATLAS South Africa, Sutherland |
Osculating 궤도요소
| 항목 |
값 |
| Epoch (epoch_cal, TDB) |
2025-06-16.0000000 |
| e |
0.94157044 |
| q (au) |
2.532201 |
| a (au) |
43.337668 |
| i (deg) |
38.543416 |
| Ω (om, deg) |
297.083175 |
| ω (w, deg) |
326.935879 |
| M (ma, deg) |
359.853978 |
밝기
산란 + 전체 선형
$$
M_a = (10.661 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
모델 상수
| 항목 |
값 |
| H0 |
10.661 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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 |
21:51:21.51 |
+27:50:26.6 |
HIP 107946 |
10.76 |
| 2026-09-20 12:00 |
21:51:05.97 |
+27:48:41.3 |
HIP 107946 |
13.94 |
| 2026-09-21 00:00 |
21:50:50.61 |
+27:46:54.6 |
HIP 107946 |
17.36 |
| 2026-09-21 12:00 |
21:50:35.46 |
+27:45:06.5 |
HIP 107946 |
20.88 |
| 2026-09-22 00:00 |
21:50:20.50 |
+27:43:17.1 |
HIP 107946 |
24.46 |
| 2026-09-22 12:00 |
21:50:05.74 |
+27:41:26.3 |
HIP 107946 |
28.05 |
| 2026-09-23 00:00 |
21:49:51.17 |
+27:39:34.4 |
HIP 107946 |
31.64 |
| 2026-09-23 12:00 |
21:49:36.81 |
+27:37:41.1 |
HIP 107946 |
35.22 |
| 2026-09-24 00:00 |
21:49:22.65 |
+27:35:46.7 |
HIP 107946 |
38.79 |
| 2026-09-24 12:00 |
21:49:08.70 |
+27:33:51.1 |
HIP 107537 |
36.67 |
| 2026-09-25 00:00 |
21:48:54.95 |
+27:31:54.4 |
HIP 107537 |
33.05 |
| 2026-09-25 12:00 |
21:48:41.41 |
+27:29:56.5 |
HIP 107537 |
29.47 |
| 2026-09-26 00:00 |
21:48:28.07 |
+27:27:57.6 |
HIP 107537 |
25.91 |
| 2026-09-26 12:00 |
21:48:14.94 |
+27:25:57.6 |
HIP 107537 |
22.38 |
| 2026-09-27 00:00 |
21:48:02.03 |
+27:23:56.7 |
HIP 107537 |
18.88 |
| 2026-09-27 12:00 |
21:47:49.32 |
+27:21:54.7 |
HIP 107537 |
15.42 |
| 2026-09-28 00:00 |
21:47:36.83 |
+27:19:51.7 |
HIP 107537 |
12.01 |
| 2026-09-28 12:00 |
21:47:24.55 |
+27:17:47.9 |
HIP 107537 |
8.65 |
| 2026-09-29 00:00 |
21:47:12.49 |
+27:15:43.1 |
HIP 107537 |
5.42 |
| 2026-09-29 12:00 |
21:47:00.64 |
+27:13:37.5 |
HIP 107537 |
2.67 |
| 2026-09-30 00:00 |
21:46:49.01 |
+27:11:31.0 |
HIP 107537 |
2.77 |
| 2026-09-30 12:00 |
21:46:37.59 |
+27:09:23.7 |
HIP 107537 |
5.50 |
| 2026-10-01 00:00 |
21:46:26.40 |
+27:07:15.6 |
HIP 107537 |
8.63 |
| 2026-10-01 12:00 |
21:46:15.42 |
+27:05:06.8 |
HIP 107537 |
11.82 |
| 2026-10-02 00:00 |
21:46:04.67 |
+27:02:57.2 |
HIP 107411 |
10.13 |
| 2026-10-02 12:00 |
21:45:54.13 |
+27:00:47.0 |
HIP 107411 |
7.38 |
| 2026-10-03 00:00 |
21:45:43.82 |
+26:58:36.1 |
HIP 107411 |
5.23 |
| 2026-10-03 12:00 |
21:45:33.73 |
+26:56:24.6 |
HIP 107411 |
4.53 |
| 2026-10-04 00:00 |
21:45:23.87 |
+26:54:12.4 |
HIP 107411 |
5.80 |
| 2026-10-04 12:00 |
21:45:14.23 |
+26:51:59.7 |
HIP 107411 |
8.13 |
| 2026-10-05 00:00 |
21:45:04.81 |
+26:49:46.4 |
HIP 107411 |
10.83 |
| 2026-10-05 12:00 |
21:44:55.62 |
+26:47:32.6 |
HIP 107411 |
13.67 |
| 2026-10-06 00:00 |
21:44:46.66 |
+26:45:18.4 |
HIP 107313 |
16.45 |
| 2026-10-06 12:00 |
21:44:37.92 |
+26:43:03.6 |
HIP 107313 |
13.53 |
| 2026-10-07 00:00 |
21:44:29.42 |
+26:40:48.5 |
HIP 107313 |
10.67 |
| 2026-10-07 12:00 |
21:44:21.14 |
+26:38:32.9 |
HIP 107313 |
7.87 |
| 2026-10-08 00:00 |
21:44:13.09 |
+26:36:17.0 |
HIP 107313 |
5.21 |
| 2026-10-08 12:00 |
21:44:05.27 |
+26:34:00.8 |
HIP 107313 |
2.99 |
| 2026-10-09 00:00 |
21:43:57.69 |
+26:31:44.2 |
HIP 107313 |
2.64 |
| 2026-10-09 12:00 |
21:43:50.33 |
+26:29:27.4 |
HIP 107313 |
4.54 |
| 2026-10-10 00:00 |
21:43:43.20 |
+26:27:10.4 |
HIP 107313 |
7.04 |
| 2026-10-10 12:00 |
21:43:36.31 |
+26:24:53.1 |
HIP 107313 |
9.66 |
| 2026-10-11 00:00 |
21:43:29.65 |
+26:22:35.6 |
HIP 107313 |
12.31 |