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)
2026-03-26 00:00 18:39:23.22 -00:17:40.9 HIP 91352 22.33
2026-03-26 12:00 18:39:23.34 -00:17:31.4 HIP 91352 22.40
2026-03-27 00:00 18:39:23.45 -00:17:21.9 HIP 91352 22.46
2026-03-27 12:00 18:39:23.54 -00:17:12.5 HIP 91352 22.53
2026-03-28 00:00 18:39:23.62 -00:17:03.0 HIP 91352 22.59
2026-03-28 12:00 18:39:23.69 -00:16:53.6 HIP 91352 22.65
2026-03-29 00:00 18:39:23.74 -00:16:44.2 HIP 91352 22.71
2026-03-29 12:00 18:39:23.78 -00:16:34.8 HIP 91352 22.76
2026-03-30 00:00 18:39:23.81 -00:16:25.4 HIP 91352 22.81
2026-03-30 12:00 18:39:23.83 -00:16:16.0 HIP 91352 22.86
2026-03-31 00:00 18:39:23.83 -00:16:06.6 HIP 91352 22.91
2026-03-31 12:00 18:39:23.81 -00:15:57.2 HIP 91352 22.96
2026-04-01 00:00 18:39:23.79 -00:15:47.9 HIP 91352 23.00
2026-04-01 12:00 18:39:23.75 -00:15:38.5 HIP 91352 23.04
2026-04-02 00:00 18:39:23.70 -00:15:29.2 HIP 91352 23.08
2026-04-02 12:00 18:39:23.63 -00:15:19.9 HIP 91352 23.12
2026-04-03 00:00 18:39:23.55 -00:15:10.6 HIP 91352 23.15
2026-04-03 12:00 18:39:23.46 -00:15:01.3 HIP 91352 23.18
2026-04-04 00:00 18:39:23.36 -00:14:52.1 HIP 91352 23.21
2026-04-04 12:00 18:39:23.24 -00:14:42.8 HIP 91352 23.24
2026-04-05 00:00 18:39:23.11 -00:14:33.6 HIP 91352 23.27
2026-04-05 12:00 18:39:22.96 -00:14:24.4 HIP 91352 23.29
2026-04-06 00:00 18:39:22.81 -00:14:15.2 HIP 91352 23.31
2026-04-06 12:00 18:39:22.64 -00:14:06.0 HIP 91352 23.33
2026-04-07 00:00 18:39:22.45 -00:13:56.8 HIP 91505 23.25
2026-04-07 12:00 18:39:22.26 -00:13:47.7 HIP 91505 23.11
2026-04-08 00:00 18:39:22.05 -00:13:38.6 HIP 91505 22.97
2026-04-08 12:00 18:39:21.83 -00:13:29.5 HIP 91505 22.83
2026-04-09 00:00 18:39:21.59 -00:13:20.4 HIP 91505 22.70
2026-04-09 12:00 18:39:21.34 -00:13:11.4 HIP 91505 22.56
2026-04-10 00:00 18:39:21.08 -00:13:02.4 HIP 91505 22.43
2026-04-10 12:00 18:39:20.80 -00:12:53.4 HIP 91505 22.30
2026-04-11 00:00 18:39:20.52 -00:12:44.4 HIP 91505 22.17
2026-04-11 12:00 18:39:20.22 -00:12:35.5 HIP 91505 22.04
2026-04-12 00:00 18:39:19.90 -00:12:26.5 HIP 91505 21.92
2026-04-12 12:00 18:39:19.58 -00:12:17.7 HIP 91505 21.79
2026-04-13 00:00 18:39:19.24 -00:12:08.8 HIP 91505 21.67
2026-04-13 12:00 18:39:18.88 -00:12:00.0 HIP 91505 21.55
2026-04-14 00:00 18:39:18.52 -00:11:51.2 HIP 91505 21.43
2026-04-14 12:00 18:39:18.14 -00:11:42.4 HIP 91505 21.31
2026-04-15 00:00 18:39:17.75 -00:11:33.6 HIP 91505 21.20
2026-04-15 12:00 18:39:17.34 -00:11:24.9 HIP 91505 21.08
2026-04-16 00:00 18:39:16.93 -00:11:16.2 HIP 91505 20.97