| Parameter |
Value |
| Designation |
C/2016 T2 (Matheny) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-12-29T02:20:01.553280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:27Z |
| Obs used |
178 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
11.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-11-29.0000000 |
| e |
0.98125057 |
| q (au) |
1.907813 |
| a (au) |
101.753121 |
| i (deg) |
81.311131 |
| Ω (om, deg) |
339.099229 |
| ω (w, deg) |
92.280552 |
| M (ma, deg) |
359.971099 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.146 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.146 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.879 |
| k |
0.986 |
| δ90 |
9.999 |
| 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) |
| 2026-09-20 00:00 |
09:37:10.88 |
-48:52:59.3 |
HIP 47184 |
7.14 |
| 2026-09-20 12:00 |
09:37:16.42 |
-48:53:53.5 |
HIP 47184 |
8.33 |
| 2026-09-21 00:00 |
09:37:21.92 |
-48:54:48.2 |
HIP 47184 |
9.54 |
| 2026-09-21 12:00 |
09:37:27.39 |
-48:55:43.2 |
HIP 47184 |
10.78 |
| 2026-09-22 00:00 |
09:37:32.82 |
-48:56:38.7 |
HIP 47184 |
12.02 |
| 2026-09-22 12:00 |
09:37:38.22 |
-48:57:34.4 |
HIP 47184 |
13.28 |
| 2026-09-23 00:00 |
09:37:43.58 |
-48:58:30.6 |
HIP 47359 |
13.27 |
| 2026-09-23 12:00 |
09:37:48.91 |
-48:59:27.1 |
HIP 47359 |
12.11 |
| 2026-09-24 00:00 |
09:37:54.21 |
-49:00:24.0 |
HIP 47359 |
10.98 |
| 2026-09-24 12:00 |
09:37:59.47 |
-49:01:21.3 |
HIP 47359 |
9.89 |
| 2026-09-25 00:00 |
09:38:04.69 |
-49:02:18.9 |
HIP 47359 |
8.86 |
| 2026-09-25 12:00 |
09:38:09.88 |
-49:03:16.9 |
HIP 47359 |
7.92 |
| 2026-09-26 00:00 |
09:38:15.03 |
-49:04:15.2 |
HIP 47359 |
7.09 |
| 2026-09-26 12:00 |
09:38:20.14 |
-49:05:13.9 |
HIP 47359 |
6.42 |
| 2026-09-27 00:00 |
09:38:25.22 |
-49:06:12.9 |
HIP 47359 |
5.97 |
| 2026-09-27 12:00 |
09:38:30.26 |
-49:07:12.2 |
HIP 47359 |
5.78 |
| 2026-09-28 00:00 |
09:38:35.26 |
-49:08:11.9 |
HIP 47359 |
5.88 |
| 2026-09-28 12:00 |
09:38:40.22 |
-49:09:12.0 |
HIP 47359 |
6.27 |
| 2026-09-29 00:00 |
09:38:45.14 |
-49:10:12.4 |
HIP 47359 |
6.88 |
| 2026-09-29 12:00 |
09:38:50.02 |
-49:11:13.1 |
HIP 47359 |
7.67 |
| 2026-09-30 00:00 |
09:38:54.87 |
-49:12:14.1 |
HIP 47359 |
8.59 |
| 2026-09-30 12:00 |
09:38:59.67 |
-49:13:15.5 |
HIP 47359 |
9.60 |
| 2026-10-01 00:00 |
09:39:04.44 |
-49:14:17.2 |
HIP 47359 |
10.67 |
| 2026-10-01 12:00 |
09:39:09.16 |
-49:15:19.2 |
HIP 47359 |
11.79 |
| 2026-10-02 00:00 |
09:39:13.84 |
-49:16:21.5 |
HIP 47359 |
12.95 |
| 2026-10-02 12:00 |
09:39:18.48 |
-49:17:24.2 |
HIP 47359 |
14.14 |
| 2026-10-03 00:00 |
09:39:23.08 |
-49:18:27.1 |
HIP 47359 |
15.34 |
| 2026-10-03 12:00 |
09:39:27.64 |
-49:19:30.4 |
HIP 47359 |
16.56 |
| 2026-10-04 00:00 |
09:39:32.15 |
-49:20:34.0 |
HIP 47359 |
17.79 |
| 2026-10-04 12:00 |
09:39:36.63 |
-49:21:37.9 |
HIP 47359 |
19.03 |
| 2026-10-05 00:00 |
09:39:41.05 |
-49:22:42.0 |
HIP 47359 |
20.29 |
| 2026-10-05 12:00 |
09:39:45.44 |
-49:23:46.5 |
HIP 47359 |
21.54 |
| 2026-10-06 00:00 |
09:39:49.78 |
-49:24:51.3 |
HIP 47359 |
22.81 |
| 2026-10-06 12:00 |
09:39:54.07 |
-49:25:56.3 |
HIP 47345 |
22.32 |
| 2026-10-07 00:00 |
09:39:58.32 |
-49:27:01.7 |
HIP 47345 |
21.70 |
| 2026-10-07 12:00 |
09:40:02.53 |
-49:28:07.3 |
HIP 47345 |
21.14 |
| 2026-10-08 00:00 |
09:40:06.69 |
-49:29:13.2 |
HIP 47345 |
20.63 |
| 2026-10-08 12:00 |
09:40:10.80 |
-49:30:19.3 |
HIP 47345 |
20.19 |
| 2026-10-09 00:00 |
09:40:14.87 |
-49:31:25.8 |
HIP 47474 |
19.28 |
| 2026-10-09 12:00 |
09:40:18.89 |
-49:32:32.5 |
HIP 47474 |
18.06 |
| 2026-10-10 00:00 |
09:40:22.86 |
-49:33:39.4 |
HIP 47474 |
16.85 |
| 2026-10-10 12:00 |
09:40:26.78 |
-49:34:46.7 |
HIP 47474 |
15.64 |
| 2026-10-11 00:00 |
09:40:30.66 |
-49:35:54.1 |
HIP 47474 |
14.45 |