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) |
| 2026-07-29 00:00 |
22:27:07.44 |
+27:21:00.6 |
HIP 110907 |
24.41 |
| 2026-07-29 12:00 |
22:26:49.00 |
+27:23:41.0 |
HIP 110783 |
22.25 |
| 2026-07-30 00:00 |
22:26:30.41 |
+27:26:18.7 |
HIP 110783 |
19.49 |
| 2026-07-30 12:00 |
22:26:11.67 |
+27:28:53.7 |
HIP 110783 |
17.74 |
| 2026-07-31 00:00 |
22:25:52.79 |
+27:31:25.9 |
HIP 110783 |
17.29 |
| 2026-07-31 12:00 |
22:25:33.76 |
+27:33:55.4 |
HIP 110783 |
18.25 |
| 2026-08-01 00:00 |
22:25:14.60 |
+27:36:22.1 |
HIP 110783 |
20.41 |
| 2026-08-01 12:00 |
22:24:55.29 |
+27:38:46.0 |
HIP 110562 |
22.53 |
| 2026-08-02 00:00 |
22:24:35.85 |
+27:41:07.1 |
HIP 110562 |
22.17 |
| 2026-08-02 12:00 |
22:24:16.28 |
+27:43:25.4 |
HIP 110562 |
22.84 |
| 2026-08-03 00:00 |
22:23:56.57 |
+27:45:40.9 |
HIP 110562 |
24.45 |
| 2026-08-03 12:00 |
22:23:36.75 |
+27:47:53.5 |
HIP 110562 |
26.83 |
| 2026-08-04 00:00 |
22:23:16.79 |
+27:50:03.4 |
HIP 110562 |
29.79 |
| 2026-08-04 12:00 |
22:22:56.72 |
+27:52:10.3 |
HIP 110562 |
33.19 |
| 2026-08-05 00:00 |
22:22:36.53 |
+27:54:14.4 |
HIP 110371 |
30.74 |
| 2026-08-05 12:00 |
22:22:16.23 |
+27:56:15.7 |
HIP 110371 |
26.70 |
| 2026-08-06 00:00 |
22:21:55.81 |
+27:58:14.1 |
HIP 110371 |
23.05 |
| 2026-08-06 12:00 |
22:21:35.29 |
+28:00:09.5 |
HIP 110371 |
19.98 |
| 2026-08-07 00:00 |
22:21:14.66 |
+28:02:02.1 |
HIP 110371 |
17.82 |
| 2026-08-07 12:00 |
22:20:53.93 |
+28:03:51.8 |
HIP 110371 |
16.92 |
| 2026-08-08 00:00 |
22:20:33.10 |
+28:05:38.6 |
HIP 110371 |
17.46 |
| 2026-08-08 12:00 |
22:20:12.18 |
+28:07:22.5 |
HIP 110371 |
19.34 |
| 2026-08-09 00:00 |
22:19:51.17 |
+28:09:03.5 |
HIP 110371 |
22.20 |
| 2026-08-09 12:00 |
22:19:30.07 |
+28:10:41.5 |
HIP 110371 |
25.74 |
| 2026-08-10 00:00 |
22:19:08.88 |
+28:12:16.7 |
HIP 110044 |
24.49 |
| 2026-08-10 12:00 |
22:18:47.62 |
+28:13:48.9 |
HIP 110044 |
20.46 |
| 2026-08-11 00:00 |
22:18:26.28 |
+28:15:18.1 |
HIP 110044 |
16.89 |
| 2026-08-11 12:00 |
22:18:04.86 |
+28:16:44.5 |
HIP 110044 |
14.12 |
| 2026-08-12 00:00 |
22:17:43.38 |
+28:18:07.9 |
HIP 110044 |
12.68 |
| 2026-08-12 12:00 |
22:17:21.83 |
+28:19:28.3 |
HIP 110044 |
13.02 |
| 2026-08-13 00:00 |
22:17:00.23 |
+28:20:45.8 |
HIP 110044 |
15.03 |
| 2026-08-13 12:00 |
22:16:38.56 |
+28:22:00.4 |
HIP 110044 |
18.15 |
| 2026-08-14 00:00 |
22:16:16.84 |
+28:23:12.1 |
HIP 110044 |
21.91 |
| 2026-08-14 12:00 |
22:15:55.07 |
+28:24:20.9 |
HIP 110044 |
26.04 |
| 2026-08-15 00:00 |
22:15:33.26 |
+28:25:26.7 |
HIP 109730 |
27.49 |
| 2026-08-15 12:00 |
22:15:11.41 |
+28:26:29.6 |
HIP 109730 |
22.69 |
| 2026-08-16 00:00 |
22:14:49.51 |
+28:27:29.6 |
HIP 109730 |
17.97 |
| 2026-08-16 12:00 |
22:14:27.59 |
+28:28:26.6 |
HIP 109730 |
13.42 |
| 2026-08-17 00:00 |
22:14:05.63 |
+28:29:20.8 |
HIP 109730 |
9.27 |
| 2026-08-17 12:00 |
22:13:43.65 |
+28:30:12.1 |
HIP 109730 |
6.37 |
| 2026-08-18 00:00 |
22:13:21.65 |
+28:31:00.5 |
HIP 109730 |
6.63 |
| 2026-08-18 12:00 |
22:12:59.62 |
+28:31:46.1 |
HIP 109730 |
9.78 |
| 2026-08-19 00:00 |
22:12:37.59 |
+28:32:28.7 |
HIP 109730 |
13.99 |