| Parameter |
Value |
| Designation |
C/2003 K1 (Spacewatch) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2002-12-21T03:39:15.825600Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:30Z |
| Obs used |
52 |
| NEO |
- |
| M1 |
14.100 |
| K1 |
8.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-05-30.0000000 |
| e |
0.95010346 |
| q (au) |
2.087130 |
| a (au) |
41.829157 |
| i (deg) |
129.831395 |
| Ω (om, deg) |
250.055839 |
| ω (w, deg) |
314.475766 |
| M (ma, deg) |
0.582360 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.875 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.875 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| δ90 |
10.000 |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
09:33:36.82 |
+61:01:32.0 |
HIP 46965 |
5.93 |
| 2026-06-01 12:00 |
09:33:38.41 |
+61:00:57.9 |
HIP 46965 |
5.53 |
| 2026-06-02 00:00 |
09:33:40.05 |
+61:00:23.9 |
HIP 46965 |
5.16 |
| 2026-06-02 12:00 |
09:33:41.72 |
+60:59:49.9 |
HIP 46965 |
4.83 |
| 2026-06-03 00:00 |
09:33:43.45 |
+60:59:15.9 |
HIP 46965 |
4.56 |
| 2026-06-03 12:00 |
09:33:45.21 |
+60:58:42.0 |
HIP 46965 |
4.35 |
| 2026-06-04 00:00 |
09:33:47.02 |
+60:58:08.1 |
HIP 46965 |
4.21 |
| 2026-06-04 12:00 |
09:33:48.88 |
+60:57:34.2 |
HIP 46965 |
4.14 |
| 2026-06-05 00:00 |
09:33:50.78 |
+60:57:00.3 |
HIP 46965 |
4.17 |
| 2026-06-05 12:00 |
09:33:52.72 |
+60:56:26.5 |
HIP 46965 |
4.27 |
| 2026-06-06 00:00 |
09:33:54.71 |
+60:55:52.8 |
HIP 46965 |
4.45 |
| 2026-06-06 12:00 |
09:33:56.74 |
+60:55:19.0 |
HIP 46965 |
4.70 |
| 2026-06-07 00:00 |
09:33:58.81 |
+60:54:45.3 |
HIP 46965 |
5.01 |
| 2026-06-07 12:00 |
09:34:00.93 |
+60:54:11.7 |
HIP 46965 |
5.37 |
| 2026-06-08 00:00 |
09:34:03.09 |
+60:53:38.1 |
HIP 46965 |
5.78 |
| 2026-06-08 12:00 |
09:34:05.29 |
+60:53:04.6 |
HIP 46965 |
6.21 |
| 2026-06-09 00:00 |
09:34:07.53 |
+60:52:31.1 |
HIP 46965 |
6.67 |
| 2026-06-09 12:00 |
09:34:09.82 |
+60:51:57.7 |
HIP 46965 |
7.16 |
| 2026-06-10 00:00 |
09:34:12.14 |
+60:51:24.3 |
HIP 46965 |
7.66 |
| 2026-06-10 12:00 |
09:34:14.51 |
+60:50:51.0 |
HIP 47043 |
7.73 |
| 2026-06-11 00:00 |
09:34:16.92 |
+60:50:17.7 |
HIP 47043 |
7.67 |
| 2026-06-11 12:00 |
09:34:19.37 |
+60:49:44.5 |
HIP 47043 |
7.66 |
| 2026-06-12 00:00 |
09:34:21.87 |
+60:49:11.4 |
HIP 47043 |
7.70 |
| 2026-06-12 12:00 |
09:34:24.40 |
+60:48:38.3 |
HIP 47043 |
7.78 |
| 2026-06-13 00:00 |
09:34:26.97 |
+60:48:05.3 |
HIP 47043 |
7.90 |
| 2026-06-13 12:00 |
09:34:29.59 |
+60:47:32.4 |
HIP 47043 |
8.07 |
| 2026-06-14 00:00 |
09:34:32.24 |
+60:46:59.6 |
HIP 47043 |
8.28 |
| 2026-06-14 12:00 |
09:34:34.94 |
+60:46:26.8 |
HIP 47043 |
8.53 |
| 2026-06-15 00:00 |
09:34:37.67 |
+60:45:54.1 |
HIP 47043 |
8.82 |
| 2026-06-15 12:00 |
09:34:40.44 |
+60:45:21.5 |
HIP 47043 |
9.14 |
| 2026-06-16 00:00 |
09:34:43.25 |
+60:44:49.0 |
HIP 47043 |
9.48 |
| 2026-06-16 12:00 |
09:34:46.10 |
+60:44:16.6 |
HIP 47043 |
9.85 |
| 2026-06-17 00:00 |
09:34:48.99 |
+60:43:44.2 |
HIP 47043 |
10.25 |
| 2026-06-17 12:00 |
09:34:51.92 |
+60:43:11.9 |
HIP 47043 |
10.67 |
| 2026-06-18 00:00 |
09:34:54.88 |
+60:42:39.8 |
HIP 47043 |
11.11 |
| 2026-06-18 12:00 |
09:34:57.89 |
+60:42:07.7 |
HIP 47043 |
11.56 |
| 2026-06-19 00:00 |
09:35:00.93 |
+60:41:35.7 |
HIP 47043 |
12.03 |
| 2026-06-19 12:00 |
09:35:04.00 |
+60:41:03.8 |
HIP 47043 |
12.52 |
| 2026-06-20 00:00 |
09:35:07.11 |
+60:40:32.1 |
HIP 47043 |
13.01 |
| 2026-06-20 12:00 |
09:35:10.26 |
+60:40:00.4 |
HIP 47043 |
13.52 |
| 2026-06-21 00:00 |
09:35:13.45 |
+60:39:28.8 |
HIP 47043 |
14.04 |
| 2026-06-21 12:00 |
09:35:16.67 |
+60:38:57.3 |
HIP 47043 |
14.57 |
| 2026-06-22 00:00 |
09:35:19.93 |
+60:38:26.0 |
HIP 47043 |
15.10 |