C/1998 M6 (Montani)
| Parameter |
Value |
| Designation |
C/1998 M6 (Montani) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-10-06T09:36:58.354560Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:57Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
7.500 |
| K1 |
10.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1998-08-01.0000000 |
| e |
0.99887950 |
| q (au) |
5.978630 |
| a (au) |
5335.660755 |
| i (deg) |
91.539988 |
| Ω (om, deg) |
306.603673 |
| ω (w, deg) |
9.130637 |
| M (ma, deg) |
359.999832 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.320 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.320 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.865 |
| k |
0.989 |
| δ90 |
1.417 |
| 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 |
09:30:54.61 |
+50:34:39.2 |
HIP 46607 |
29.27 |
| 2026-02-03 12:00 |
09:30:50.51 |
+50:34:49.4 |
HIP 46607 |
28.96 |
| 2026-02-04 00:00 |
09:30:46.40 |
+50:34:59.3 |
HIP 46607 |
28.67 |
| 2026-02-04 12:00 |
09:30:42.29 |
+50:35:09.1 |
HIP 46607 |
28.40 |
| 2026-02-05 00:00 |
09:30:38.18 |
+50:35:18.6 |
HIP 46607 |
28.14 |
| 2026-02-05 12:00 |
09:30:34.06 |
+50:35:28.0 |
HIP 46607 |
27.90 |
| 2026-02-06 00:00 |
09:30:29.94 |
+50:35:37.1 |
HIP 46607 |
27.68 |
| 2026-02-06 12:00 |
09:30:25.82 |
+50:35:46.0 |
HIP 46607 |
27.48 |
| 2026-02-07 00:00 |
09:30:21.70 |
+50:35:54.7 |
HIP 46607 |
27.29 |
| 2026-02-07 12:00 |
09:30:17.58 |
+50:36:03.3 |
HIP 46385 |
26.64 |
| 2026-02-08 00:00 |
09:30:13.45 |
+50:36:11.5 |
HIP 46385 |
25.98 |
| 2026-02-08 12:00 |
09:30:09.33 |
+50:36:19.6 |
HIP 46385 |
25.31 |
| 2026-02-09 00:00 |
09:30:05.20 |
+50:36:27.5 |
HIP 46385 |
24.65 |
| 2026-02-09 12:00 |
09:30:01.08 |
+50:36:35.2 |
HIP 46385 |
23.98 |
| 2026-02-10 00:00 |
09:29:56.95 |
+50:36:42.6 |
HIP 46385 |
23.32 |
| 2026-02-10 12:00 |
09:29:52.82 |
+50:36:49.8 |
HIP 46385 |
22.65 |
| 2026-02-11 00:00 |
09:29:48.70 |
+50:36:56.8 |
HIP 46385 |
21.99 |
| 2026-02-11 12:00 |
09:29:44.58 |
+50:37:03.6 |
HIP 46385 |
21.33 |
| 2026-02-12 00:00 |
09:29:40.45 |
+50:37:10.2 |
HIP 46385 |
20.67 |
| 2026-02-12 12:00 |
09:29:36.33 |
+50:37:16.5 |
HIP 46385 |
20.00 |
| 2026-02-13 00:00 |
09:29:32.22 |
+50:37:22.7 |
HIP 46385 |
19.34 |
| 2026-02-13 12:00 |
09:29:28.10 |
+50:37:28.6 |
HIP 46385 |
18.69 |
| 2026-02-14 00:00 |
09:29:23.99 |
+50:37:34.3 |
HIP 46385 |
18.03 |
| 2026-02-14 12:00 |
09:29:19.88 |
+50:37:39.7 |
HIP 46385 |
17.37 |
| 2026-02-15 00:00 |
09:29:15.78 |
+50:37:45.0 |
HIP 46385 |
16.71 |
| 2026-02-15 12:00 |
09:29:11.68 |
+50:37:50.0 |
HIP 46385 |
16.06 |
| 2026-02-16 00:00 |
09:29:07.58 |
+50:37:54.8 |
HIP 46385 |
15.40 |
| 2026-02-16 12:00 |
09:29:03.49 |
+50:37:59.4 |
HIP 46385 |
14.75 |
| 2026-02-17 00:00 |
09:28:59.40 |
+50:38:03.8 |
HIP 46385 |
14.10 |
| 2026-02-17 12:00 |
09:28:55.32 |
+50:38:07.9 |
HIP 46385 |
13.45 |
| 2026-02-18 00:00 |
09:28:51.25 |
+50:38:11.8 |
HIP 46385 |
12.80 |
| 2026-02-18 12:00 |
09:28:47.18 |
+50:38:15.5 |
HIP 46385 |
12.15 |
| 2026-02-19 00:00 |
09:28:43.12 |
+50:38:18.9 |
HIP 46385 |
11.51 |
| 2026-02-19 12:00 |
09:28:39.06 |
+50:38:22.2 |
HIP 46385 |
10.86 |
| 2026-02-20 00:00 |
09:28:35.01 |
+50:38:25.2 |
HIP 46385 |
10.22 |
| 2026-02-20 12:00 |
09:28:30.97 |
+50:38:27.9 |
HIP 46385 |
9.57 |
| 2026-02-21 00:00 |
09:28:26.94 |
+50:38:30.5 |
HIP 46385 |
8.93 |
| 2026-02-21 12:00 |
09:28:22.92 |
+50:38:32.8 |
HIP 46385 |
8.29 |
| 2026-02-22 00:00 |
09:28:18.90 |
+50:38:34.9 |
HIP 46385 |
7.66 |
| 2026-02-22 12:00 |
09:28:14.89 |
+50:38:36.7 |
HIP 46385 |
7.02 |
| 2026-02-23 00:00 |
09:28:10.90 |
+50:38:38.4 |
HIP 46385 |
6.39 |
| 2026-02-23 12:00 |
09:28:06.91 |
+50:38:39.8 |
HIP 46385 |
5.76 |
| 2026-02-24 00:00 |
09:28:02.93 |
+50:38:41.0 |
HIP 46385 |
5.13 |