| Parameter |
Value |
| Designation |
C/2012 CH17 (MOSS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-09-28T05:20:29.244480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:03Z |
| Obs used |
627 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-04-06.0000000 |
| e |
0.99998818 |
| q (au) |
1.296093 |
| a (au) |
109657.782316 |
| i (deg) |
27.744192 |
| Ω (om, deg) |
125.984715 |
| ω (w, deg) |
137.993552 |
| M (ma, deg) |
359.999995 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.872 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.872 |
| n |
2.000 |
| gf |
0.800 |
| gb |
-0.865 |
| k |
1.000 |
| δ90 |
1.000 |
| 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) |
| 2026-03-26 00:00 |
04:16:00.59 |
-03:47:26.5 |
HIP 19873 |
16.23 |
| 2026-03-26 12:00 |
04:16:02.59 |
-03:46:59.8 |
HIP 19873 |
15.94 |
| 2026-03-27 00:00 |
04:16:04.62 |
-03:46:33.1 |
HIP 19873 |
15.66 |
| 2026-03-27 12:00 |
04:16:06.68 |
-03:46:06.5 |
HIP 19873 |
15.42 |
| 2026-03-28 00:00 |
04:16:08.76 |
-03:45:39.9 |
HIP 19873 |
15.21 |
| 2026-03-28 12:00 |
04:16:10.87 |
-03:45:13.4 |
HIP 19873 |
15.02 |
| 2026-03-29 00:00 |
04:16:13.01 |
-03:44:46.9 |
HIP 19873 |
14.88 |
| 2026-03-29 12:00 |
04:16:15.17 |
-03:44:20.5 |
HIP 19873 |
14.76 |
| 2026-03-30 00:00 |
04:16:17.36 |
-03:43:54.2 |
HIP 19873 |
14.69 |
| 2026-03-30 12:00 |
04:16:19.57 |
-03:43:27.9 |
HIP 19873 |
14.65 |
| 2026-03-31 00:00 |
04:16:21.81 |
-03:43:01.7 |
HIP 19873 |
14.65 |
| 2026-03-31 12:00 |
04:16:24.08 |
-03:42:35.6 |
HIP 19873 |
14.69 |
| 2026-04-01 00:00 |
04:16:26.37 |
-03:42:09.5 |
HIP 19873 |
14.77 |
| 2026-04-01 12:00 |
04:16:28.68 |
-03:41:43.5 |
HIP 19873 |
14.88 |
| 2026-04-02 00:00 |
04:16:31.02 |
-03:41:17.5 |
HIP 19873 |
15.04 |
| 2026-04-02 12:00 |
04:16:33.39 |
-03:40:51.7 |
HIP 19873 |
15.24 |
| 2026-04-03 00:00 |
04:16:35.78 |
-03:40:25.9 |
HIP 19873 |
15.47 |
| 2026-04-03 12:00 |
04:16:38.19 |
-03:40:00.1 |
HIP 19873 |
15.74 |
| 2026-04-04 00:00 |
04:16:40.63 |
-03:39:34.5 |
HIP 19873 |
16.05 |
| 2026-04-04 12:00 |
04:16:43.09 |
-03:39:08.9 |
HIP 19873 |
16.39 |
| 2026-04-05 00:00 |
04:16:45.57 |
-03:38:43.5 |
HIP 19873 |
16.76 |
| 2026-04-05 12:00 |
04:16:48.08 |
-03:38:18.0 |
HIP 19873 |
17.17 |
| 2026-04-06 00:00 |
04:16:50.61 |
-03:37:52.7 |
HIP 19873 |
17.60 |
| 2026-04-06 12:00 |
04:16:53.17 |
-03:37:27.5 |
HIP 19873 |
18.06 |
| 2026-04-07 00:00 |
04:16:55.75 |
-03:37:02.3 |
HIP 19873 |
18.55 |
| 2026-04-07 12:00 |
04:16:58.35 |
-03:36:37.3 |
HIP 19873 |
19.06 |
| 2026-04-08 00:00 |
04:17:00.98 |
-03:36:12.3 |
HIP 19873 |
19.59 |
| 2026-04-08 12:00 |
04:17:03.62 |
-03:35:47.4 |
HIP 19873 |
20.15 |
| 2026-04-09 00:00 |
04:17:06.29 |
-03:35:22.6 |
HIP 19873 |
20.72 |
| 2026-04-09 12:00 |
04:17:08.98 |
-03:34:57.9 |
HIP 19873 |
21.32 |
| 2026-04-10 00:00 |
04:17:11.70 |
-03:34:33.3 |
HIP 19873 |
21.93 |
| 2026-04-10 12:00 |
04:17:14.43 |
-03:34:08.8 |
HIP 19873 |
22.56 |
| 2026-04-11 00:00 |
04:17:17.19 |
-03:33:44.3 |
HIP 19873 |
23.20 |
| 2026-04-11 12:00 |
04:17:19.97 |
-03:33:20.0 |
HIP 19873 |
23.86 |
| 2026-04-12 00:00 |
04:17:22.77 |
-03:32:55.8 |
HIP 19873 |
24.54 |
| 2026-04-12 12:00 |
04:17:25.59 |
-03:32:31.7 |
HIP 19873 |
25.23 |
| 2026-04-13 00:00 |
04:17:28.44 |
-03:32:07.7 |
HIP 19873 |
25.92 |
| 2026-04-13 12:00 |
04:17:31.30 |
-03:31:43.8 |
HIP 19873 |
26.64 |
| 2026-04-14 00:00 |
04:17:34.18 |
-03:31:20.0 |
HIP 19873 |
27.36 |
| 2026-04-14 12:00 |
04:17:37.09 |
-03:30:56.3 |
HIP 19873 |
28.09 |
| 2026-04-15 00:00 |
04:17:40.01 |
-03:30:32.7 |
HIP 20166 |
27.78 |
| 2026-04-15 12:00 |
04:17:42.96 |
-03:30:09.2 |
HIP 20166 |
26.95 |
| 2026-04-16 00:00 |
04:17:45.92 |
-03:29:45.9 |
HIP 20166 |
26.11 |