C/1975 X1 (Sato)

Metadata

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

C/1975 X1 (Sato) · Magnitude (Full range)

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)
2026-09-20 00:00 18:33:28.58 -00:15:57.3 HIP 90932 9.14
2026-09-20 12:00 18:33:28.32 -00:16:05.9 HIP 90932 9.02
2026-09-21 00:00 18:33:28.07 -00:16:14.6 HIP 90932 8.91
2026-09-21 12:00 18:33:27.84 -00:16:23.2 HIP 90932 8.80
2026-09-22 00:00 18:33:27.62 -00:16:31.8 HIP 90932 8.69
2026-09-22 12:00 18:33:27.41 -00:16:40.5 HIP 90932 8.59
2026-09-23 00:00 18:33:27.21 -00:16:49.1 HIP 90932 8.49
2026-09-23 12:00 18:33:27.03 -00:16:57.7 HIP 90932 8.40
2026-09-24 00:00 18:33:26.86 -00:17:06.3 HIP 90932 8.31
2026-09-24 12:00 18:33:26.70 -00:17:15.0 HIP 90932 8.23
2026-09-25 00:00 18:33:26.56 -00:17:23.6 HIP 90932 8.15
2026-09-25 12:00 18:33:26.42 -00:17:32.2 HIP 90932 8.08
2026-09-26 00:00 18:33:26.31 -00:17:40.8 HIP 90932 8.01
2026-09-26 12:00 18:33:26.20 -00:17:49.4 HIP 90932 7.94
2026-09-27 00:00 18:33:26.11 -00:17:58.0 HIP 90932 7.89
2026-09-27 12:00 18:33:26.03 -00:18:06.6 HIP 90932 7.84
2026-09-28 00:00 18:33:25.96 -00:18:15.2 HIP 90932 7.79
2026-09-28 12:00 18:33:25.91 -00:18:23.7 HIP 90932 7.75
2026-09-29 00:00 18:33:25.87 -00:18:32.3 HIP 90932 7.71
2026-09-29 12:00 18:33:25.84 -00:18:40.8 HIP 90932 7.69
2026-09-30 00:00 18:33:25.83 -00:18:49.4 HIP 90932 7.66
2026-09-30 12:00 18:33:25.82 -00:18:57.9 HIP 90932 7.64
2026-10-01 00:00 18:33:25.84 -00:19:06.4 HIP 90932 7.63
2026-10-01 12:00 18:33:25.86 -00:19:15.0 HIP 90932 7.63
2026-10-02 00:00 18:33:25.90 -00:19:23.5 HIP 90932 7.63
2026-10-02 12:00 18:33:25.95 -00:19:31.9 HIP 90932 7.63
2026-10-03 00:00 18:33:26.01 -00:19:40.4 HIP 90932 7.65
2026-10-03 12:00 18:33:26.09 -00:19:48.9 HIP 90932 7.66
2026-10-04 00:00 18:33:26.18 -00:19:57.3 HIP 90932 7.69
2026-10-04 12:00 18:33:26.29 -00:20:05.7 HIP 90932 7.72
2026-10-05 00:00 18:33:26.40 -00:20:14.1 HIP 90932 7.75
2026-10-05 12:00 18:33:26.53 -00:20:22.5 HIP 90932 7.79
2026-10-06 00:00 18:33:26.67 -00:20:30.9 HIP 90932 7.84
2026-10-06 12:00 18:33:26.83 -00:20:39.3 HIP 90932 7.89
2026-10-07 00:00 18:33:27.00 -00:20:47.6 HIP 90932 7.95
2026-10-07 12:00 18:33:27.18 -00:20:55.9 HIP 90932 8.01
2026-10-08 00:00 18:33:27.38 -00:21:04.2 HIP 90932 8.08
2026-10-08 12:00 18:33:27.58 -00:21:12.5 HIP 90932 8.16
2026-10-09 00:00 18:33:27.80 -00:21:20.8 HIP 90932 8.23
2026-10-09 12:00 18:33:28.04 -00:21:29.0 HIP 90932 8.32
2026-10-10 00:00 18:33:28.29 -00:21:37.2 HIP 90932 8.41
2026-10-10 12:00 18:33:28.55 -00:21:45.4 HIP 90932 8.50
2026-10-11 00:00 18:33:28.82 -00:21:53.5 HIP 90932 8.60