| 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) |
| 2026-05-12 00:00 |
18:38:38.81 |
-00:04:43.2 |
HIP 91505 |
20.53 |
| 2026-05-12 12:00 |
18:38:37.79 |
-00:04:37.0 |
HIP 91505 |
20.66 |
| 2026-05-13 00:00 |
18:38:36.75 |
-00:04:30.9 |
HIP 91322 |
20.70 |
| 2026-05-13 12:00 |
18:38:35.71 |
-00:04:24.8 |
HIP 91322 |
20.58 |
| 2026-05-14 00:00 |
18:38:34.66 |
-00:04:18.8 |
HIP 91322 |
20.46 |
| 2026-05-14 12:00 |
18:38:33.60 |
-00:04:12.8 |
HIP 91322 |
20.34 |
| 2026-05-15 00:00 |
18:38:32.53 |
-00:04:07.0 |
HIP 91322 |
20.22 |
| 2026-05-15 12:00 |
18:38:31.45 |
-00:04:01.1 |
HIP 91322 |
20.10 |
| 2026-05-16 00:00 |
18:38:30.36 |
-00:03:55.4 |
HIP 91322 |
19.98 |
| 2026-05-16 12:00 |
18:38:29.26 |
-00:03:49.7 |
HIP 91322 |
19.87 |
| 2026-05-17 00:00 |
18:38:28.15 |
-00:03:44.0 |
HIP 91322 |
19.76 |
| 2026-05-17 12:00 |
18:38:27.03 |
-00:03:38.4 |
HIP 91322 |
19.64 |
| 2026-05-18 00:00 |
18:38:25.91 |
-00:03:32.9 |
HIP 91322 |
19.53 |
| 2026-05-18 12:00 |
18:38:24.77 |
-00:03:27.5 |
HIP 91322 |
19.42 |
| 2026-05-19 00:00 |
18:38:23.63 |
-00:03:22.1 |
HIP 91322 |
19.31 |
| 2026-05-19 12:00 |
18:38:22.48 |
-00:03:16.8 |
HIP 91322 |
19.21 |
| 2026-05-20 00:00 |
18:38:21.32 |
-00:03:11.5 |
HIP 91322 |
19.10 |
| 2026-05-20 12:00 |
18:38:20.15 |
-00:03:06.4 |
HIP 91322 |
19.00 |
| 2026-05-21 00:00 |
18:38:18.97 |
-00:03:01.2 |
HIP 91322 |
18.90 |
| 2026-05-21 12:00 |
18:38:17.78 |
-00:02:56.2 |
HIP 91322 |
18.80 |
| 2026-05-22 00:00 |
18:38:16.59 |
-00:02:51.2 |
HIP 91322 |
18.71 |
| 2026-05-22 12:00 |
18:38:15.39 |
-00:02:46.3 |
HIP 91322 |
18.62 |
| 2026-05-23 00:00 |
18:38:14.18 |
-00:02:41.5 |
HIP 91322 |
18.53 |
| 2026-05-23 12:00 |
18:38:12.96 |
-00:02:36.7 |
HIP 91322 |
18.44 |
| 2026-05-24 00:00 |
18:38:11.73 |
-00:02:32.0 |
HIP 91322 |
18.36 |
| 2026-05-24 12:00 |
18:38:10.50 |
-00:02:27.3 |
HIP 91322 |
18.28 |
| 2026-05-25 00:00 |
18:38:09.26 |
-00:02:22.8 |
HIP 91322 |
18.20 |
| 2026-05-25 12:00 |
18:38:08.01 |
-00:02:18.3 |
HIP 91322 |
18.13 |
| 2026-05-26 00:00 |
18:38:06.75 |
-00:02:13.8 |
HIP 91322 |
18.06 |
| 2026-05-26 12:00 |
18:38:05.49 |
-00:02:09.5 |
HIP 91322 |
17.99 |
| 2026-05-27 00:00 |
18:38:04.21 |
-00:02:05.2 |
HIP 91322 |
17.93 |
| 2026-05-27 12:00 |
18:38:02.94 |
-00:02:00.9 |
HIP 91322 |
17.87 |
| 2026-05-28 00:00 |
18:38:01.65 |
-00:01:56.8 |
HIP 91322 |
17.82 |
| 2026-05-28 12:00 |
18:38:00.36 |
-00:01:52.7 |
HIP 91322 |
17.77 |
| 2026-05-29 00:00 |
18:37:59.06 |
-00:01:48.7 |
HIP 91322 |
17.72 |
| 2026-05-29 12:00 |
18:37:57.75 |
-00:01:44.7 |
HIP 91322 |
17.68 |
| 2026-05-30 00:00 |
18:37:56.44 |
-00:01:40.9 |
HIP 91322 |
17.64 |
| 2026-05-30 12:00 |
18:37:55.12 |
-00:01:37.1 |
HIP 91322 |
17.61 |
| 2026-05-31 00:00 |
18:37:53.79 |
-00:01:33.3 |
HIP 91322 |
17.58 |
| 2026-05-31 12:00 |
18:37:52.46 |
-00:01:29.7 |
HIP 91322 |
17.56 |
| 2026-06-01 00:00 |
18:37:51.12 |
-00:01:26.1 |
HIP 91322 |
17.54 |
| 2026-06-01 12:00 |
18:37:49.78 |
-00:01:22.6 |
HIP 91322 |
17.53 |
| 2026-06-02 00:00 |
18:37:48.42 |
-00:01:19.2 |
HIP 91322 |
17.53 |