| Parameter |
Value |
| Designation |
C/2016 T3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-09-06T23:30:05.921280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:27Z |
| Obs used |
436 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
4.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-06-25.0000000 |
| e |
0.98138749 |
| q (au) |
2.649481 |
| a (au) |
142.349476 |
| i (deg) |
22.675960 |
| Ω (om, deg) |
271.748362 |
| ω (w, deg) |
194.677924 |
| M (ma, deg) |
359.957068 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.344 + 2.067\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.344 |
| n |
2.067 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2016-10-10 |
2017-09-06 |
+7.4124 |
-4.382 |
| 2017-09-17 |
2018-04-18 |
+5.6541 |
-2.485 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
16:09:31.51 |
-30:19:46.3 |
HIP 79127 |
7.27 |
| 2026-09-20 12:00 |
16:09:34.67 |
-30:19:39.0 |
HIP 79127 |
7.77 |
| 2026-09-21 00:00 |
16:09:37.89 |
-30:19:31.8 |
HIP 79127 |
8.30 |
| 2026-09-21 12:00 |
16:09:41.14 |
-30:19:24.8 |
HIP 79127 |
8.87 |
| 2026-09-22 00:00 |
16:09:44.44 |
-30:19:18.0 |
HIP 79127 |
9.47 |
| 2026-09-22 12:00 |
16:09:47.79 |
-30:19:11.3 |
HIP 79127 |
10.10 |
| 2026-09-23 00:00 |
16:09:51.17 |
-30:19:04.8 |
HIP 79127 |
10.75 |
| 2026-09-23 12:00 |
16:09:54.61 |
-30:18:58.4 |
HIP 79127 |
11.42 |
| 2026-09-24 00:00 |
16:09:58.08 |
-30:18:52.2 |
HIP 79127 |
12.10 |
| 2026-09-24 12:00 |
16:10:01.60 |
-30:18:46.2 |
HIP 79127 |
12.81 |
| 2026-09-25 00:00 |
16:10:05.17 |
-30:18:40.3 |
HIP 79127 |
13.53 |
| 2026-09-25 12:00 |
16:10:08.77 |
-30:18:34.6 |
HIP 79249 |
13.68 |
| 2026-09-26 00:00 |
16:10:12.42 |
-30:18:29.0 |
HIP 79249 |
13.60 |
| 2026-09-26 12:00 |
16:10:16.11 |
-30:18:23.6 |
HIP 79249 |
13.56 |
| 2026-09-27 00:00 |
16:10:19.84 |
-30:18:18.3 |
HIP 79249 |
13.57 |
| 2026-09-27 12:00 |
16:10:23.62 |
-30:18:13.3 |
HIP 79249 |
13.62 |
| 2026-09-28 00:00 |
16:10:27.44 |
-30:18:08.3 |
HIP 79249 |
13.72 |
| 2026-09-28 12:00 |
16:10:31.29 |
-30:18:03.6 |
HIP 79249 |
13.87 |
| 2026-09-29 00:00 |
16:10:35.19 |
-30:17:59.0 |
HIP 79249 |
14.06 |
| 2026-09-29 12:00 |
16:10:39.14 |
-30:17:54.5 |
HIP 79249 |
14.30 |
| 2026-09-30 00:00 |
16:10:43.12 |
-30:17:50.2 |
HIP 79249 |
14.59 |
| 2026-09-30 12:00 |
16:10:47.14 |
-30:17:46.1 |
HIP 79249 |
14.92 |
| 2026-10-01 00:00 |
16:10:51.20 |
-30:17:42.1 |
HIP 79249 |
15.30 |
| 2026-10-01 12:00 |
16:10:55.31 |
-30:17:38.3 |
HIP 79249 |
15.71 |
| 2026-10-02 00:00 |
16:10:59.45 |
-30:17:34.7 |
HIP 79249 |
16.17 |
| 2026-10-02 12:00 |
16:11:03.64 |
-30:17:31.2 |
HIP 79249 |
16.66 |
| 2026-10-03 00:00 |
16:11:07.86 |
-30:17:27.8 |
HIP 79249 |
17.19 |
| 2026-10-03 12:00 |
16:11:12.12 |
-30:17:24.7 |
HIP 79249 |
17.75 |
| 2026-10-04 00:00 |
16:11:16.42 |
-30:17:21.7 |
HIP 79249 |
18.35 |
| 2026-10-04 12:00 |
16:11:20.76 |
-30:17:18.8 |
HIP 79430 |
18.93 |
| 2026-10-05 00:00 |
16:11:25.14 |
-30:17:16.1 |
HIP 79430 |
18.06 |
| 2026-10-05 12:00 |
16:11:29.56 |
-30:17:13.5 |
HIP 79430 |
17.19 |
| 2026-10-06 00:00 |
16:11:34.02 |
-30:17:11.2 |
HIP 79430 |
16.33 |
| 2026-10-06 12:00 |
16:11:38.51 |
-30:17:08.9 |
HIP 79430 |
15.48 |
| 2026-10-07 00:00 |
16:11:43.04 |
-30:17:06.9 |
HIP 79430 |
14.63 |
| 2026-10-07 12:00 |
16:11:47.61 |
-30:17:04.9 |
HIP 79430 |
13.80 |
| 2026-10-08 00:00 |
16:11:52.22 |
-30:17:03.2 |
HIP 79430 |
12.98 |
| 2026-10-08 12:00 |
16:11:56.86 |
-30:17:01.6 |
HIP 79430 |
12.18 |
| 2026-10-09 00:00 |
16:12:01.54 |
-30:17:00.1 |
HIP 79430 |
11.42 |
| 2026-10-09 12:00 |
16:12:06.25 |
-30:16:58.8 |
HIP 79430 |
10.69 |
| 2026-10-10 00:00 |
16:12:11.01 |
-30:16:57.7 |
HIP 79430 |
10.00 |
| 2026-10-10 12:00 |
16:12:15.79 |
-30:16:56.7 |
HIP 79430 |
9.38 |
| 2026-10-11 00:00 |
16:12:20.61 |
-30:16:55.9 |
HIP 79430 |
8.84 |