| Parameter |
Value |
| Designation |
283P/Spacewatch |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-04-06T23:45:57.098880Z |
| Orbit solution date (soln_date, UTC) |
2022-05-19T21:14:11Z |
| Obs used |
114 |
| NEO |
- |
| M1 |
16.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-03-13.0000000 |
| e |
0.48567912 |
| q (au) |
2.126445 |
| a (au) |
4.134471 |
| i (deg) |
14.464365 |
| Ω (om, deg) |
161.248171 |
| ω (w, deg) |
21.995380 |
| M (ma, deg) |
314.277725 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
01:40:42.18 |
+01:24:32.6 |
HIP 7842 |
13.38 |
| 2026-07-29 12:00 |
01:40:45.29 |
+01:23:45.7 |
HIP 7842 |
14.04 |
| 2026-07-30 00:00 |
01:40:48.27 |
+01:22:57.7 |
HIP 7842 |
14.76 |
| 2026-07-30 12:00 |
01:40:51.09 |
+01:22:08.8 |
HIP 7842 |
15.55 |
| 2026-07-31 00:00 |
01:40:53.76 |
+01:21:18.9 |
HIP 7842 |
16.39 |
| 2026-07-31 12:00 |
01:40:56.28 |
+01:20:28.1 |
HIP 7842 |
17.26 |
| 2026-08-01 00:00 |
01:40:58.65 |
+01:19:36.3 |
HIP 7842 |
18.17 |
| 2026-08-01 12:00 |
01:41:00.87 |
+01:18:43.5 |
HIP 7842 |
19.10 |
| 2026-08-02 00:00 |
01:41:02.94 |
+01:17:49.7 |
HIP 7842 |
20.06 |
| 2026-08-02 12:00 |
01:41:04.86 |
+01:16:55.0 |
HIP 7842 |
21.03 |
| 2026-08-03 00:00 |
01:41:06.62 |
+01:15:59.3 |
HIP 7842 |
22.01 |
| 2026-08-03 12:00 |
01:41:08.23 |
+01:15:02.6 |
HIP 7842 |
23.01 |
| 2026-08-04 00:00 |
01:41:09.69 |
+01:14:04.9 |
HIP 7842 |
24.02 |
| 2026-08-04 12:00 |
01:41:10.99 |
+01:13:06.3 |
HIP 7842 |
25.04 |
| 2026-08-05 00:00 |
01:41:12.14 |
+01:12:06.7 |
HIP 7842 |
26.07 |
| 2026-08-05 12:00 |
01:41:13.13 |
+01:11:06.2 |
HIP 7871 |
26.57 |
| 2026-08-06 00:00 |
01:41:13.97 |
+01:10:04.7 |
HIP 7871 |
25.53 |
| 2026-08-06 12:00 |
01:41:14.65 |
+01:09:02.2 |
HIP 7871 |
24.49 |
| 2026-08-07 00:00 |
01:41:15.18 |
+01:07:58.7 |
HIP 7871 |
23.43 |
| 2026-08-07 12:00 |
01:41:15.55 |
+01:06:54.3 |
HIP 7871 |
22.35 |
| 2026-08-08 00:00 |
01:41:15.76 |
+01:05:49.0 |
HIP 7871 |
21.26 |
| 2026-08-08 12:00 |
01:41:15.82 |
+01:04:42.7 |
HIP 7871 |
20.16 |
| 2026-08-09 00:00 |
01:41:15.71 |
+01:03:35.4 |
HIP 7871 |
19.04 |
| 2026-08-09 12:00 |
01:41:15.45 |
+01:02:27.2 |
HIP 7871 |
17.90 |
| 2026-08-10 00:00 |
01:41:15.03 |
+01:01:18.0 |
HIP 7871 |
16.75 |
| 2026-08-10 12:00 |
01:41:14.46 |
+01:00:07.9 |
HIP 7871 |
15.59 |
| 2026-08-11 00:00 |
01:41:13.72 |
+00:58:56.8 |
HIP 7871 |
14.42 |
| 2026-08-11 12:00 |
01:41:12.82 |
+00:57:44.8 |
HIP 7871 |
13.24 |
| 2026-08-12 00:00 |
01:41:11.77 |
+00:56:31.9 |
HIP 7871 |
12.05 |
| 2026-08-12 12:00 |
01:41:10.55 |
+00:55:18.0 |
HIP 7871 |
10.87 |
| 2026-08-13 00:00 |
01:41:09.18 |
+00:54:03.2 |
HIP 7871 |
9.71 |
| 2026-08-13 12:00 |
01:41:07.65 |
+00:52:47.5 |
HIP 7871 |
8.58 |
| 2026-08-14 00:00 |
01:41:05.95 |
+00:51:30.9 |
HIP 7871 |
7.51 |
| 2026-08-14 12:00 |
01:41:04.10 |
+00:50:13.3 |
HIP 7871 |
6.55 |
| 2026-08-15 00:00 |
01:41:02.09 |
+00:48:54.9 |
HIP 7871 |
5.78 |
| 2026-08-15 12:00 |
01:40:59.92 |
+00:47:35.5 |
HIP 7871 |
5.29 |
| 2026-08-16 00:00 |
01:40:57.58 |
+00:46:15.3 |
HIP 7871 |
5.20 |
| 2026-08-16 12:00 |
01:40:55.09 |
+00:44:54.2 |
HIP 7871 |
5.55 |
| 2026-08-17 00:00 |
01:40:52.44 |
+00:43:32.2 |
HIP 7871 |
6.29 |
| 2026-08-17 12:00 |
01:40:49.63 |
+00:42:09.3 |
HIP 7871 |
7.31 |
| 2026-08-18 00:00 |
01:40:46.66 |
+00:40:45.5 |
HIP 7871 |
8.54 |
| 2026-08-18 12:00 |
01:40:43.53 |
+00:39:20.8 |
HIP 7871 |
9.91 |
| 2026-08-19 00:00 |
01:40:40.25 |
+00:37:55.3 |
HIP 7871 |
11.39 |