C/2017 M3 (PANSTARRS)
| Parameter |
Value |
| Designation |
C/2017 M3 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-04-28T06:37:59.880000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:35Z |
| Obs used |
65 |
| NEO |
- |
| M1 |
7.300 |
| K1 |
15.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-10-29.0000000 |
| e |
0.97323499 |
| q (au) |
4.656283 |
| a (au) |
173.969005 |
| i (deg) |
77.506843 |
| Ω (om, deg) |
6.997266 |
| ω (w, deg) |
110.325474 |
| M (ma, deg) |
0.078915 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.736 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.736 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.501 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
11:35:34.13 |
-57:30:43.5 |
HIP 56442 |
12.06 |
| 2026-02-03 12:00 |
11:35:25.55 |
-57:31:32.5 |
HIP 56442 |
10.65 |
| 2026-02-04 00:00 |
11:35:16.91 |
-57:32:20.9 |
HIP 56442 |
9.23 |
| 2026-02-04 12:00 |
11:35:08.20 |
-57:33:08.6 |
HIP 56442 |
7.82 |
| 2026-02-05 00:00 |
11:34:59.43 |
-57:33:55.6 |
HIP 56442 |
6.41 |
| 2026-02-05 12:00 |
11:34:50.59 |
-57:34:42.0 |
HIP 56442 |
4.99 |
| 2026-02-06 00:00 |
11:34:41.69 |
-57:35:27.7 |
HIP 56442 |
3.58 |
| 2026-02-06 12:00 |
11:34:32.73 |
-57:36:12.7 |
HIP 56442 |
2.18 |
| 2026-02-07 00:00 |
11:34:23.71 |
-57:36:57.1 |
HIP 56442 |
0.81 |
| 2026-02-07 12:00 |
11:34:14.62 |
-57:37:40.7 |
HIP 56442 |
0.78 |
| 2026-02-08 00:00 |
11:34:05.47 |
-57:38:23.7 |
HIP 56442 |
2.14 |
| 2026-02-08 12:00 |
11:33:56.27 |
-57:39:06.0 |
HIP 56393 |
2.29 |
| 2026-02-09 00:00 |
11:33:47.00 |
-57:39:47.6 |
HIP 56393 |
1.49 |
| 2026-02-09 12:00 |
11:33:37.68 |
-57:40:28.5 |
HIP 56393 |
1.78 |
| 2026-02-10 00:00 |
11:33:28.30 |
-57:41:08.7 |
HIP 56393 |
2.86 |
| 2026-02-10 12:00 |
11:33:18.86 |
-57:41:48.2 |
HIP 56393 |
4.14 |
| 2026-02-11 00:00 |
11:33:09.37 |
-57:42:27.0 |
HIP 56393 |
5.49 |
| 2026-02-11 12:00 |
11:32:59.82 |
-57:43:05.1 |
HIP 56393 |
6.87 |
| 2026-02-12 00:00 |
11:32:50.22 |
-57:43:42.5 |
HIP 56393 |
8.26 |
| 2026-02-12 12:00 |
11:32:40.56 |
-57:44:19.1 |
HIP 56393 |
9.66 |
| 2026-02-13 00:00 |
11:32:30.86 |
-57:44:55.0 |
HIP 56393 |
11.07 |
| 2026-02-13 12:00 |
11:32:21.10 |
-57:45:30.2 |
HIP 56393 |
12.48 |
| 2026-02-14 00:00 |
11:32:11.28 |
-57:46:04.7 |
HIP 56393 |
13.89 |
| 2026-02-14 12:00 |
11:32:01.42 |
-57:46:38.5 |
HIP 56393 |
15.30 |
| 2026-02-15 00:00 |
11:31:51.51 |
-57:47:11.5 |
HIP 56393 |
16.72 |
| 2026-02-15 12:00 |
11:31:41.55 |
-57:47:43.8 |
HIP 56393 |
18.14 |
| 2026-02-16 00:00 |
11:31:31.55 |
-57:48:15.3 |
HIP 56057 |
17.44 |
| 2026-02-16 12:00 |
11:31:21.49 |
-57:48:46.1 |
HIP 56057 |
16.06 |
| 2026-02-17 00:00 |
11:31:11.39 |
-57:49:16.2 |
HIP 56057 |
14.69 |
| 2026-02-17 12:00 |
11:31:01.25 |
-57:49:45.5 |
HIP 56057 |
13.32 |
| 2026-02-18 00:00 |
11:30:51.06 |
-57:50:14.1 |
HIP 56057 |
11.96 |
| 2026-02-18 12:00 |
11:30:40.83 |
-57:50:41.9 |
HIP 56057 |
10.63 |
| 2026-02-19 00:00 |
11:30:30.56 |
-57:51:09.0 |
HIP 56057 |
9.31 |
| 2026-02-19 12:00 |
11:30:20.25 |
-57:51:35.3 |
HIP 56057 |
8.03 |
| 2026-02-20 00:00 |
11:30:09.90 |
-57:52:00.9 |
HIP 56057 |
6.80 |
| 2026-02-20 12:00 |
11:29:59.51 |
-57:52:25.7 |
HIP 56057 |
5.67 |
| 2026-02-21 00:00 |
11:29:49.08 |
-57:52:49.8 |
HIP 56057 |
4.70 |
| 2026-02-21 12:00 |
11:29:38.61 |
-57:53:13.1 |
HIP 56057 |
4.01 |
| 2026-02-22 00:00 |
11:29:28.11 |
-57:53:35.6 |
HIP 56057 |
3.76 |
| 2026-02-22 12:00 |
11:29:17.58 |
-57:53:57.4 |
HIP 56057 |
4.04 |
| 2026-02-23 00:00 |
11:29:07.01 |
-57:54:18.4 |
HIP 56057 |
4.75 |
| 2026-02-23 12:00 |
11:28:56.41 |
-57:54:38.6 |
HIP 56057 |
5.74 |
| 2026-02-24 00:00 |
11:28:45.78 |
-57:54:58.1 |
HIP 56057 |
6.88 |