293P/Spacewatch
| Parameter |
Value |
| Designation |
293P/Spacewatch |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-01-10T06:55:08.644800Z |
| Orbit solution date (soln_date, UTC) |
2022-06-12T21:06:40Z |
| Obs used |
463 |
| NEO |
- |
| M1 |
15.800 |
| K1 |
7.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-01-02.0000000 |
| e |
0.41974111 |
| q (au) |
2.111752 |
| a (au) |
3.639328 |
| i (deg) |
9.064844 |
| Ω (om, deg) |
78.437790 |
| ω (w, deg) |
41.152848 |
| M (ma, deg) |
358.823377 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.488 + 2.988\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.488 |
| n |
2.988 |
| gf |
0.999 |
| gb |
-0.716 |
| k |
0.994 |
| 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) |
| 2026-02-03 00:00 |
22:48:24.21 |
-15:40:59.1 |
HIP 112504 |
31.73 |
| 2026-02-03 12:00 |
22:48:52.51 |
-15:37:52.6 |
HIP 112526 |
35.61 |
| 2026-02-04 00:00 |
22:49:20.86 |
-15:34:46.0 |
HIP 112526 |
37.45 |
| 2026-02-04 12:00 |
22:49:49.26 |
-15:31:39.1 |
HIP 112526 |
40.62 |
| 2026-02-05 00:00 |
22:50:17.71 |
-15:28:32.0 |
HIP 112959 |
34.85 |
| 2026-02-05 12:00 |
22:50:46.21 |
-15:25:24.6 |
HIP 112959 |
27.39 |
| 2026-02-06 00:00 |
22:51:14.76 |
-15:22:17.1 |
HIP 112959 |
19.97 |
| 2026-02-06 12:00 |
22:51:43.36 |
-15:19:09.3 |
HIP 112959 |
12.71 |
| 2026-02-07 00:00 |
22:52:12.01 |
-15:16:01.4 |
HIP 112959 |
6.23 |
| 2026-02-07 12:00 |
22:52:40.70 |
-15:12:53.2 |
HIP 112959 |
5.57 |
| 2026-02-08 00:00 |
22:53:09.45 |
-15:09:44.9 |
HIP 112959 |
11.79 |
| 2026-02-08 12:00 |
22:53:38.23 |
-15:06:36.3 |
HIP 113117 |
12.80 |
| 2026-02-09 00:00 |
22:54:07.07 |
-15:03:27.6 |
HIP 113117 |
5.20 |
| 2026-02-09 12:00 |
22:54:35.95 |
-15:00:18.7 |
HIP 113117 |
2.64 |
| 2026-02-10 00:00 |
22:55:04.87 |
-14:57:09.5 |
HIP 113117 |
10.21 |
| 2026-02-10 12:00 |
22:55:33.84 |
-14:54:00.2 |
HIP 113292 |
14.62 |
| 2026-02-11 00:00 |
22:56:02.85 |
-14:50:50.8 |
HIP 113292 |
10.78 |
| 2026-02-11 12:00 |
22:56:31.91 |
-14:47:41.1 |
HIP 113292 |
11.70 |
| 2026-02-12 00:00 |
22:57:01.00 |
-14:44:31.3 |
HIP 113292 |
16.62 |
| 2026-02-12 12:00 |
22:57:30.14 |
-14:41:21.4 |
HIP 113378 |
14.80 |
| 2026-02-13 00:00 |
22:57:59.32 |
-14:38:11.2 |
HIP 113378 |
11.93 |
| 2026-02-13 12:00 |
22:58:28.54 |
-14:35:01.0 |
HIP 113378 |
13.62 |
| 2026-02-14 00:00 |
22:58:57.80 |
-14:31:50.5 |
HIP 113378 |
18.69 |
| 2026-02-14 12:00 |
22:59:27.09 |
-14:28:40.0 |
HIP 113631 |
23.58 |
| 2026-02-15 00:00 |
22:59:56.43 |
-14:25:29.2 |
HIP 113631 |
15.97 |
| 2026-02-15 12:00 |
23:00:25.80 |
-14:22:18.4 |
HIP 113631 |
8.65 |
| 2026-02-16 00:00 |
23:00:55.21 |
-14:19:07.4 |
HIP 113631 |
4.04 |
| 2026-02-16 12:00 |
23:01:24.65 |
-14:15:56.3 |
HIP 113675 |
0.37 |
| 2026-02-17 00:00 |
23:01:54.13 |
-14:12:45.1 |
HIP 113675 |
7.94 |
| 2026-02-17 12:00 |
23:02:23.65 |
-14:09:33.7 |
HIP 113798 |
7.51 |
| 2026-02-18 00:00 |
23:02:53.19 |
-14:06:22.3 |
HIP 113798 |
9.11 |
| 2026-02-18 12:00 |
23:03:22.78 |
-14:03:10.7 |
HIP 113798 |
15.26 |
| 2026-02-19 00:00 |
23:03:52.39 |
-13:59:59.0 |
HIP 113798 |
22.50 |
| 2026-02-19 12:00 |
23:04:22.03 |
-13:56:47.3 |
HIP 113798 |
30.07 |
| 2026-02-20 00:00 |
23:04:51.71 |
-13:53:35.4 |
HIP 114094 |
25.39 |
| 2026-02-20 12:00 |
23:05:21.42 |
-13:50:23.5 |
HIP 114094 |
17.53 |
| 2026-02-21 00:00 |
23:05:51.15 |
-13:47:11.4 |
HIP 114094 |
9.73 |
| 2026-02-21 12:00 |
23:06:20.92 |
-13:43:59.3 |
HIP 114094 |
2.54 |
| 2026-02-22 00:00 |
23:06:50.71 |
-13:40:47.2 |
HIP 114094 |
6.59 |
| 2026-02-22 12:00 |
23:07:20.53 |
-13:37:34.9 |
HIP 114094 |
14.35 |
| 2026-02-23 00:00 |
23:07:50.38 |
-13:34:22.6 |
HIP 114311 |
19.44 |
| 2026-02-23 12:00 |
23:08:20.25 |
-13:31:10.2 |
HIP 114311 |
15.59 |
| 2026-02-24 00:00 |
23:08:50.15 |
-13:27:57.8 |
HIP 114311 |
15.31 |