| Parameter |
Value |
| Designation |
C/2017 M5 (TOTAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-06-02T22:39:17.565120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:35Z |
| Obs used |
461 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
10.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-04-23.0000000 |
| e |
1.00373842 |
| q (au) |
5.989567 |
| a (au) |
-1602.163329 |
| i (deg) |
15.884843 |
| Ω (om, deg) |
216.263268 |
| ω (w, deg) |
92.657463 |
| M (ma, deg) |
-0.000629 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.478 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.478 |
| n |
6.000 |
| gf |
0.801 |
| gb |
-0.884 |
| k |
1.000 |
| δ90 |
3.757 |
| 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 |
| 2016-03-06 |
2018-05-22 |
+9.8447 |
-8.185 |
| 2018-08-08 |
2019-12-02 |
+11.7631 |
-9.198 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
03:47:43.27 |
+14:04:34.0 |
HIP 17714 |
1.37 |
| 2026-05-12 12:00 |
03:47:50.52 |
+14:04:54.1 |
HIP 17714 |
2.98 |
| 2026-05-13 00:00 |
03:47:57.78 |
+14:05:14.1 |
HIP 17714 |
4.73 |
| 2026-05-13 12:00 |
03:48:05.05 |
+14:05:34.1 |
HIP 17714 |
6.50 |
| 2026-05-14 00:00 |
03:48:12.32 |
+14:05:54.0 |
HIP 17714 |
8.28 |
| 2026-05-14 12:00 |
03:48:19.59 |
+14:06:13.8 |
HIP 17714 |
10.07 |
| 2026-05-15 00:00 |
03:48:26.87 |
+14:06:33.5 |
HIP 17714 |
11.86 |
| 2026-05-15 12:00 |
03:48:34.15 |
+14:06:53.2 |
HIP 17714 |
13.65 |
| 2026-05-16 00:00 |
03:48:41.44 |
+14:07:12.7 |
HIP 17714 |
15.44 |
| 2026-05-16 12:00 |
03:48:48.72 |
+14:07:32.2 |
HIP 17714 |
17.24 |
| 2026-05-17 00:00 |
03:48:56.01 |
+14:07:51.6 |
HIP 17714 |
19.03 |
| 2026-05-17 12:00 |
03:49:03.30 |
+14:08:10.8 |
HIP 17714 |
20.82 |
| 2026-05-18 00:00 |
03:49:10.59 |
+14:08:30.0 |
HIP 17714 |
22.62 |
| 2026-05-18 12:00 |
03:49:17.88 |
+14:08:49.1 |
HIP 17714 |
24.42 |
| 2026-05-19 00:00 |
03:49:25.18 |
+14:09:08.2 |
HIP 17714 |
26.21 |
| 2026-05-19 12:00 |
03:49:32.47 |
+14:09:27.1 |
HIP 17714 |
28.01 |
| 2026-05-20 00:00 |
03:49:39.76 |
+14:09:45.9 |
HIP 17714 |
29.80 |
| 2026-05-20 12:00 |
03:49:47.05 |
+14:10:04.6 |
HIP 17714 |
31.59 |
| 2026-05-21 00:00 |
03:49:54.34 |
+14:10:23.3 |
HIP 17714 |
33.39 |
| 2026-05-21 12:00 |
03:50:01.63 |
+14:10:41.8 |
HIP 17726 |
34.99 |
| 2026-05-22 00:00 |
03:50:08.91 |
+14:11:00.2 |
HIP 17726 |
36.59 |
| 2026-05-22 12:00 |
03:50:16.20 |
+14:11:18.6 |
HIP 17726 |
38.19 |
| 2026-05-23 00:00 |
03:50:23.48 |
+14:11:36.8 |
HIP 18145 |
37.85 |
| 2026-05-23 12:00 |
03:50:30.76 |
+14:11:54.9 |
HIP 18145 |
36.36 |
| 2026-05-24 00:00 |
03:50:38.03 |
+14:12:13.0 |
HIP 18145 |
34.89 |
| 2026-05-24 12:00 |
03:50:45.30 |
+14:12:30.9 |
HIP 18158 |
33.22 |
| 2026-05-25 00:00 |
03:50:52.57 |
+14:12:48.7 |
HIP 18158 |
31.46 |
| 2026-05-25 12:00 |
03:50:59.83 |
+14:13:06.4 |
HIP 18158 |
29.70 |
| 2026-05-26 00:00 |
03:51:07.09 |
+14:13:24.0 |
HIP 18158 |
27.95 |
| 2026-05-26 12:00 |
03:51:14.34 |
+14:13:41.5 |
HIP 18158 |
26.20 |
| 2026-05-27 00:00 |
03:51:21.59 |
+14:13:58.9 |
HIP 18158 |
24.46 |
| 2026-05-27 12:00 |
03:51:28.83 |
+14:14:16.2 |
HIP 18158 |
22.72 |
| 2026-05-28 00:00 |
03:51:36.07 |
+14:14:33.3 |
HIP 18158 |
21.00 |
| 2026-05-28 12:00 |
03:51:43.29 |
+14:14:50.4 |
HIP 18158 |
19.28 |
| 2026-05-29 00:00 |
03:51:50.52 |
+14:15:07.3 |
HIP 18158 |
17.58 |
| 2026-05-29 12:00 |
03:51:57.73 |
+14:15:24.1 |
HIP 18158 |
15.90 |
| 2026-05-30 00:00 |
03:52:04.94 |
+14:15:40.8 |
HIP 18158 |
14.25 |
| 2026-05-30 12:00 |
03:52:12.14 |
+14:15:57.4 |
HIP 18158 |
12.62 |
| 2026-05-31 00:00 |
03:52:19.33 |
+14:16:13.9 |
HIP 18158 |
11.04 |
| 2026-05-31 12:00 |
03:52:26.51 |
+14:16:30.3 |
HIP 18158 |
9.54 |
| 2026-06-01 00:00 |
03:52:33.69 |
+14:16:46.5 |
HIP 18158 |
8.13 |
| 2026-06-01 12:00 |
03:52:40.85 |
+14:17:02.6 |
HIP 18158 |
6.90 |
| 2026-06-02 00:00 |
03:52:48.01 |
+14:17:18.6 |
HIP 18158 |
5.93 |