| 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
$$
M_a = (2.460 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.460 |
| n |
6.000 |
| gf |
0.895 |
| gb |
-0.884 |
| k |
1.000 |
| δ90 |
3.916 |
| 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 |
+11.7630 |
-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) |
| 2026-09-20 00:00 |
04:06:13.14 |
+14:12:09.6 |
HIP 19085 |
11.36 |
| 2026-09-20 12:00 |
04:06:11.61 |
+14:11:50.9 |
HIP 19085 |
11.17 |
| 2026-09-21 00:00 |
04:06:10.02 |
+14:11:32.1 |
HIP 19085 |
10.99 |
| 2026-09-21 12:00 |
04:06:08.38 |
+14:11:13.1 |
HIP 19085 |
10.82 |
| 2026-09-22 00:00 |
04:06:06.69 |
+14:10:54.1 |
HIP 19085 |
10.67 |
| 2026-09-22 12:00 |
04:06:04.95 |
+14:10:34.9 |
HIP 19085 |
10.53 |
| 2026-09-23 00:00 |
04:06:03.16 |
+14:10:15.6 |
HIP 19085 |
10.40 |
| 2026-09-23 12:00 |
04:06:01.32 |
+14:09:56.2 |
HIP 19085 |
10.30 |
| 2026-09-24 00:00 |
04:05:59.42 |
+14:09:36.8 |
HIP 19085 |
10.22 |
| 2026-09-24 12:00 |
04:05:57.48 |
+14:09:17.2 |
HIP 19085 |
10.16 |
| 2026-09-25 00:00 |
04:05:55.49 |
+14:08:57.5 |
HIP 19085 |
10.13 |
| 2026-09-25 12:00 |
04:05:53.45 |
+14:08:37.7 |
HIP 19085 |
10.12 |
| 2026-09-26 00:00 |
04:05:51.36 |
+14:08:17.8 |
HIP 19085 |
10.15 |
| 2026-09-26 12:00 |
04:05:49.22 |
+14:07:57.8 |
HIP 19085 |
10.21 |
| 2026-09-27 00:00 |
04:05:47.02 |
+14:07:37.7 |
HIP 19085 |
10.30 |
| 2026-09-27 12:00 |
04:05:44.79 |
+14:07:17.5 |
HIP 19085 |
10.43 |
| 2026-09-28 00:00 |
04:05:42.50 |
+14:06:57.2 |
HIP 19085 |
10.60 |
| 2026-09-28 12:00 |
04:05:40.16 |
+14:06:36.8 |
HIP 19085 |
10.80 |
| 2026-09-29 00:00 |
04:05:37.78 |
+14:06:16.3 |
HIP 19085 |
11.03 |
| 2026-09-29 12:00 |
04:05:35.34 |
+14:05:55.7 |
HIP 19085 |
11.30 |
| 2026-09-30 00:00 |
04:05:32.86 |
+14:05:35.0 |
HIP 19085 |
11.61 |
| 2026-09-30 12:00 |
04:05:30.33 |
+14:05:14.3 |
HIP 19085 |
11.95 |
| 2026-10-01 00:00 |
04:05:27.75 |
+14:04:53.4 |
HIP 19085 |
12.32 |
| 2026-10-01 12:00 |
04:05:25.13 |
+14:04:32.5 |
HIP 19085 |
12.72 |
| 2026-10-02 00:00 |
04:05:22.46 |
+14:04:11.4 |
HIP 19085 |
13.16 |
| 2026-10-02 12:00 |
04:05:19.74 |
+14:03:50.3 |
HIP 19085 |
13.63 |
| 2026-10-03 00:00 |
04:05:16.97 |
+14:03:29.1 |
HIP 19085 |
14.12 |
| 2026-10-03 12:00 |
04:05:14.16 |
+14:03:07.8 |
HIP 19085 |
14.64 |
| 2026-10-04 00:00 |
04:05:11.30 |
+14:02:46.5 |
HIP 19085 |
15.19 |
| 2026-10-04 12:00 |
04:05:08.40 |
+14:02:25.0 |
HIP 19085 |
15.76 |
| 2026-10-05 00:00 |
04:05:05.44 |
+14:02:03.5 |
HIP 19085 |
16.35 |
| 2026-10-05 12:00 |
04:05:02.45 |
+14:01:41.9 |
HIP 19085 |
16.97 |
| 2026-10-06 00:00 |
04:04:59.40 |
+14:01:20.2 |
HIP 19085 |
17.61 |
| 2026-10-06 12:00 |
04:04:56.32 |
+14:00:58.5 |
HIP 19085 |
18.27 |
| 2026-10-07 00:00 |
04:04:53.19 |
+14:00:36.7 |
HIP 19085 |
18.95 |
| 2026-10-07 12:00 |
04:04:50.01 |
+14:00:14.8 |
HIP 19085 |
19.65 |
| 2026-10-08 00:00 |
04:04:46.79 |
+13:59:52.8 |
HIP 18927 |
19.94 |
| 2026-10-08 12:00 |
04:04:43.52 |
+13:59:30.8 |
HIP 18927 |
19.10 |
| 2026-10-09 00:00 |
04:04:40.21 |
+13:59:08.7 |
HIP 18927 |
18.25 |
| 2026-10-09 12:00 |
04:04:36.86 |
+13:58:46.5 |
HIP 18927 |
17.39 |
| 2026-10-10 00:00 |
04:04:33.47 |
+13:58:24.3 |
HIP 18927 |
16.53 |
| 2026-10-10 12:00 |
04:04:30.03 |
+13:58:02.0 |
HIP 18927 |
15.66 |
| 2026-10-11 00:00 |
04:04:26.55 |
+13:57:39.7 |
HIP 18927 |
14.79 |