| Parameter |
Value |
| Designation |
C/1975 X1 (Sato) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1976-01-03T22:01:50.992320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:24Z |
| Obs used |
72 |
| NEO |
- |
| M1 |
11.100 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1975-12-19.0000000 |
| e |
1.00150800 |
| q (au) |
0.863970 |
| a (au) |
-572.924348 |
| i (deg) |
93.957122 |
| Ω (om, deg) |
281.495433 |
| ω (w, deg) |
215.462906 |
| M (ma, deg) |
-0.001144 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.258 + 5.272\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.258 |
| n |
5.272 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
1.000 |
| 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) |
| 2026-07-29 00:00 |
18:35:00.77 |
-00:03:00.2 |
HIP 91113 |
5.89 |
| 2026-07-29 12:00 |
18:34:59.42 |
-00:03:05.2 |
HIP 91113 |
6.08 |
| 2026-07-30 00:00 |
18:34:58.08 |
-00:03:10.3 |
HIP 91113 |
6.29 |
| 2026-07-30 12:00 |
18:34:56.75 |
-00:03:15.4 |
HIP 91113 |
6.50 |
| 2026-07-31 00:00 |
18:34:55.42 |
-00:03:20.6 |
HIP 91113 |
6.73 |
| 2026-07-31 12:00 |
18:34:54.10 |
-00:03:25.8 |
HIP 91113 |
6.97 |
| 2026-08-01 00:00 |
18:34:52.78 |
-00:03:31.1 |
HIP 91113 |
7.22 |
| 2026-08-01 12:00 |
18:34:51.47 |
-00:03:36.4 |
HIP 91113 |
7.47 |
| 2026-08-02 00:00 |
18:34:50.17 |
-00:03:41.9 |
HIP 91113 |
7.73 |
| 2026-08-02 12:00 |
18:34:48.88 |
-00:03:47.3 |
HIP 91113 |
8.00 |
| 2026-08-03 00:00 |
18:34:47.59 |
-00:03:52.9 |
HIP 91113 |
8.27 |
| 2026-08-03 12:00 |
18:34:46.31 |
-00:03:58.4 |
HIP 91113 |
8.54 |
| 2026-08-04 00:00 |
18:34:45.04 |
-00:04:04.1 |
HIP 91113 |
8.82 |
| 2026-08-04 12:00 |
18:34:43.77 |
-00:04:09.8 |
HIP 91113 |
9.10 |
| 2026-08-05 00:00 |
18:34:42.51 |
-00:04:15.6 |
HIP 91113 |
9.39 |
| 2026-08-05 12:00 |
18:34:41.26 |
-00:04:21.4 |
HIP 91113 |
9.67 |
| 2026-08-06 00:00 |
18:34:40.01 |
-00:04:27.2 |
HIP 91113 |
9.96 |
| 2026-08-06 12:00 |
18:34:38.78 |
-00:04:33.2 |
HIP 91113 |
10.25 |
| 2026-08-07 00:00 |
18:34:37.55 |
-00:04:39.2 |
HIP 91113 |
10.54 |
| 2026-08-07 12:00 |
18:34:36.33 |
-00:04:45.2 |
HIP 91113 |
10.83 |
| 2026-08-08 00:00 |
18:34:35.12 |
-00:04:51.3 |
HIP 91113 |
11.12 |
| 2026-08-08 12:00 |
18:34:33.91 |
-00:04:57.4 |
HIP 91113 |
11.42 |
| 2026-08-09 00:00 |
18:34:32.71 |
-00:05:03.6 |
HIP 91113 |
11.71 |
| 2026-08-09 12:00 |
18:34:31.52 |
-00:05:09.9 |
HIP 91113 |
12.01 |
| 2026-08-10 00:00 |
18:34:30.34 |
-00:05:16.2 |
HIP 91113 |
12.30 |
| 2026-08-10 12:00 |
18:34:29.17 |
-00:05:22.5 |
HIP 91113 |
12.59 |
| 2026-08-11 00:00 |
18:34:28.01 |
-00:05:28.9 |
HIP 91113 |
12.89 |
| 2026-08-11 12:00 |
18:34:26.85 |
-00:05:35.4 |
HIP 91113 |
13.18 |
| 2026-08-12 00:00 |
18:34:25.70 |
-00:05:41.9 |
HIP 91113 |
13.47 |
| 2026-08-12 12:00 |
18:34:24.57 |
-00:05:48.5 |
HIP 91113 |
13.76 |
| 2026-08-13 00:00 |
18:34:23.44 |
-00:05:55.1 |
HIP 91113 |
14.06 |
| 2026-08-13 12:00 |
18:34:22.32 |
-00:06:01.7 |
HIP 91113 |
14.35 |
| 2026-08-14 00:00 |
18:34:21.21 |
-00:06:08.4 |
HIP 91113 |
14.63 |
| 2026-08-14 12:00 |
18:34:20.10 |
-00:06:15.2 |
HIP 91113 |
14.92 |
| 2026-08-15 00:00 |
18:34:19.01 |
-00:06:22.0 |
HIP 91113 |
15.21 |
| 2026-08-15 12:00 |
18:34:17.93 |
-00:06:28.8 |
HIP 91113 |
15.50 |
| 2026-08-16 00:00 |
18:34:16.85 |
-00:06:35.7 |
HIP 91113 |
15.78 |
| 2026-08-16 12:00 |
18:34:15.79 |
-00:06:42.7 |
HIP 91113 |
16.07 |
| 2026-08-17 00:00 |
18:34:14.73 |
-00:06:49.7 |
HIP 91113 |
16.35 |
| 2026-08-17 12:00 |
18:34:13.69 |
-00:06:56.7 |
HIP 91113 |
16.63 |
| 2026-08-18 00:00 |
18:34:12.65 |
-00:07:03.8 |
HIP 91113 |
16.91 |
| 2026-08-18 12:00 |
18:34:11.62 |
-00:07:10.9 |
HIP 91113 |
17.19 |
| 2026-08-19 00:00 |
18:34:10.61 |
-00:07:18.0 |
HIP 91113 |
17.47 |