| Parameter |
Value |
| Designation |
C/1981 M1 (Gonzalez) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1981-03-25T15:42:23.296320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:29Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1981-08-07.0000000 |
| e |
0.99935134 |
| q (au) |
2.333585 |
| a (au) |
3597.566450 |
| i (deg) |
107.144868 |
| Ω (om, deg) |
143.968785 |
| ω (w, deg) |
181.611922 |
| M (ma, deg) |
0.000614 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.178 + 2.822\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.178 |
| n |
2.822 |
| gf |
0.991 |
| gb |
-0.978 |
| k |
1.000 |
| δ90 |
9.999 |
| 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) |
| 2026-07-29 00:00 |
09:41:16.51 |
-05:29:20.7 |
HIP 47284 |
49.82 |
| 2026-07-29 12:00 |
09:41:18.02 |
-05:29:25.0 |
HIP 47284 |
50.20 |
| 2026-07-30 00:00 |
09:41:19.54 |
-05:29:29.3 |
HIP 47284 |
50.57 |
| 2026-07-30 12:00 |
09:41:21.07 |
-05:29:33.6 |
HIP 47284 |
50.95 |
| 2026-07-31 00:00 |
09:41:22.59 |
-05:29:38.1 |
HIP 47284 |
51.33 |
| 2026-07-31 12:00 |
09:41:24.13 |
-05:29:42.7 |
HIP 47284 |
51.71 |
| 2026-08-01 00:00 |
09:41:25.66 |
-05:29:47.3 |
HIP 47284 |
52.09 |
| 2026-08-01 12:00 |
09:41:27.20 |
-05:29:52.0 |
HIP 47284 |
52.48 |
| 2026-08-02 00:00 |
09:41:28.74 |
-05:29:56.8 |
HIP 47284 |
52.86 |
| 2026-08-02 12:00 |
09:41:30.28 |
-05:30:01.7 |
HIP 47284 |
53.25 |
| 2026-08-03 00:00 |
09:41:31.83 |
-05:30:06.7 |
HIP 47539 |
53.50 |
| 2026-08-03 12:00 |
09:41:33.38 |
-05:30:11.7 |
HIP 47539 |
53.41 |
| 2026-08-04 00:00 |
09:41:34.93 |
-05:30:16.9 |
HIP 47539 |
53.33 |
| 2026-08-04 12:00 |
09:41:36.49 |
-05:30:22.1 |
HIP 47539 |
53.25 |
| 2026-08-05 00:00 |
09:41:38.04 |
-05:30:27.4 |
HIP 47539 |
53.18 |
| 2026-08-05 12:00 |
09:41:39.60 |
-05:30:32.7 |
HIP 47539 |
53.10 |
| 2026-08-06 00:00 |
09:41:41.17 |
-05:30:38.2 |
HIP 47539 |
53.02 |
| 2026-08-06 12:00 |
09:41:42.73 |
-05:30:43.7 |
HIP 47539 |
52.95 |
| 2026-08-07 00:00 |
09:41:44.30 |
-05:30:49.4 |
HIP 47539 |
52.88 |
| 2026-08-07 12:00 |
09:41:45.86 |
-05:30:55.0 |
HIP 47539 |
52.81 |
| 2026-08-08 00:00 |
09:41:47.44 |
-05:31:00.8 |
HIP 47539 |
52.74 |
| 2026-08-08 12:00 |
09:41:49.01 |
-05:31:06.7 |
HIP 47539 |
52.67 |
| 2026-08-09 00:00 |
09:41:50.58 |
-05:31:12.6 |
HIP 47757 |
52.55 |
| 2026-08-09 12:00 |
09:41:52.16 |
-05:31:18.6 |
HIP 47757 |
52.22 |
| 2026-08-10 00:00 |
09:41:53.73 |
-05:31:24.7 |
HIP 47757 |
51.88 |
| 2026-08-10 12:00 |
09:41:55.31 |
-05:31:30.8 |
HIP 47757 |
51.55 |
| 2026-08-11 00:00 |
09:41:56.89 |
-05:31:37.1 |
HIP 47757 |
51.22 |
| 2026-08-11 12:00 |
09:41:58.47 |
-05:31:43.4 |
HIP 47757 |
50.89 |
| 2026-08-12 00:00 |
09:42:00.05 |
-05:31:49.8 |
HIP 47757 |
50.55 |
| 2026-08-12 12:00 |
09:42:01.64 |
-05:31:56.2 |
HIP 47757 |
50.22 |
| 2026-08-13 00:00 |
09:42:03.22 |
-05:32:02.8 |
HIP 47757 |
49.89 |
| 2026-08-13 12:00 |
09:42:04.80 |
-05:32:09.4 |
HIP 47757 |
49.55 |
| 2026-08-14 00:00 |
09:42:06.39 |
-05:32:16.1 |
HIP 47757 |
49.22 |
| 2026-08-14 12:00 |
09:42:07.97 |
-05:32:22.8 |
HIP 47757 |
48.89 |
| 2026-08-15 00:00 |
09:42:09.56 |
-05:32:29.6 |
HIP 47757 |
48.56 |
| 2026-08-15 12:00 |
09:42:11.14 |
-05:32:36.5 |
HIP 47757 |
48.22 |
| 2026-08-16 00:00 |
09:42:12.73 |
-05:32:43.5 |
HIP 47757 |
47.89 |
| 2026-08-16 12:00 |
09:42:14.31 |
-05:32:50.6 |
HIP 47757 |
47.56 |
| 2026-08-17 00:00 |
09:42:15.90 |
-05:32:57.7 |
HIP 47757 |
47.23 |
| 2026-08-17 12:00 |
09:42:17.48 |
-05:33:04.8 |
HIP 47757 |
46.90 |
| 2026-08-18 00:00 |
09:42:19.07 |
-05:33:12.1 |
HIP 47757 |
46.57 |
| 2026-08-18 12:00 |
09:42:20.65 |
-05:33:19.4 |
HIP 47757 |
46.24 |
| 2026-08-19 00:00 |
09:42:22.24 |
-05:33:26.8 |
HIP 47757 |
45.91 |