C/2019 G4 (PANSTARRS)

Metadata

Parameter Value
Designation C/2019 G4 (PANSTARRS)
Type C
Perihelion (tp_cal, UTC) 2018-09-16T16:19:43.942080Z
Orbit solution date (soln_date, UTC) 2023-04-24T19:06:38Z
Obs used 7
NEO -
M1 13.800
K1 4.500
PC -
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2020-01-04.0000000
e 1.00013440
q (au) 5.864733
a (au) -43634.843792
i (deg) 138.390694
Ω (om, deg) 130.459931
ω (w, deg) 287.998779
M (ma, deg) 0.000051

Magnitude

C/2019 G4 (PANSTARRS) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (4.578 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 4.578
n 6.000
gf 0.861
gb -0.985
k 1.000
δ90 3.282
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 07:06:55.17 +47:15:08.4 HIP 34366 10.52
2026-09-20 12:00 07:06:56.57 +47:15:55.7 HIP 34366 11.12
2026-09-21 00:00 07:06:57.89 +47:16:43.2 HIP 34366 11.75
2026-09-21 12:00 07:06:59.13 +47:17:30.8 HIP 34366 12.41
2026-09-22 00:00 07:07:00.31 +47:18:18.7 HIP 34366 13.10
2026-09-22 12:00 07:07:01.40 +47:19:06.8 HIP 34366 13.81
2026-09-23 00:00 07:07:02.43 +47:19:55.1 HIP 34366 14.54
2026-09-23 12:00 07:07:03.37 +47:20:43.5 HIP 34366 15.28
2026-09-24 00:00 07:07:04.24 +47:21:32.2 HIP 34366 16.04
2026-09-24 12:00 07:07:05.04 +47:22:21.1 HIP 34366 16.81
2026-09-25 00:00 07:07:05.76 +47:23:10.2 HIP 34366 17.59
2026-09-25 12:00 07:07:06.40 +47:23:59.4 HIP 34366 18.38
2026-09-26 00:00 07:07:06.97 +47:24:48.9 HIP 34366 19.18
2026-09-26 12:00 07:07:07.46 +47:25:38.5 HIP 34366 19.99
2026-09-27 00:00 07:07:07.87 +47:26:28.3 HIP 34366 20.80
2026-09-27 12:00 07:07:08.21 +47:27:18.3 HIP 34375 20.67
2026-09-28 00:00 07:07:08.46 +47:28:08.5 HIP 34375 19.85
2026-09-28 12:00 07:07:08.64 +47:28:58.9 HIP 34375 19.02
2026-09-29 00:00 07:07:08.74 +47:29:49.4 HIP 34375 18.20
2026-09-29 12:00 07:07:08.77 +47:30:40.1 HIP 34375 17.38
2026-09-30 00:00 07:07:08.71 +47:31:31.0 HIP 34375 16.57
2026-09-30 12:00 07:07:08.57 +47:32:22.1 HIP 34375 15.76
2026-10-01 00:00 07:07:08.36 +47:33:13.3 HIP 34375 14.95
2026-10-01 12:00 07:07:08.06 +47:34:04.7 HIP 34375 14.15
2026-10-02 00:00 07:07:07.69 +47:34:56.2 HIP 34375 13.37
2026-10-02 12:00 07:07:07.23 +47:35:47.9 HIP 34375 12.59
2026-10-03 00:00 07:07:06.70 +47:36:39.8 HIP 34375 11.83
2026-10-03 12:00 07:07:06.08 +47:37:31.8 HIP 34375 11.09
2026-10-04 00:00 07:07:05.38 +47:38:24.0 HIP 34375 10.37
2026-10-04 12:00 07:07:04.60 +47:39:16.3 HIP 34375 9.69
2026-10-05 00:00 07:07:03.74 +47:40:08.8 HIP 34375 9.05
2026-10-05 12:00 07:07:02.79 +47:41:01.4 HIP 34375 8.46
2026-10-06 00:00 07:07:01.77 +47:41:54.1 HIP 34375 7.93
2026-10-06 12:00 07:07:00.66 +47:42:47.0 HIP 34375 7.48
2026-10-07 00:00 07:06:59.47 +47:43:40.0 HIP 34375 7.14
2026-10-07 12:00 07:06:58.19 +47:44:33.2 HIP 34375 6.90
2026-10-08 00:00 07:06:56.83 +47:45:26.5 HIP 34375 6.79
2026-10-08 12:00 07:06:55.39 +47:46:19.9 HIP 34375 6.82
2026-10-09 00:00 07:06:53.86 +47:47:13.4 HIP 34375 6.98
2026-10-09 12:00 07:06:52.25 +47:48:07.0 HIP 34375 7.28
2026-10-10 00:00 07:06:50.56 +47:49:00.8 HIP 34375 7.69
2026-10-10 12:00 07:06:48.78 +47:49:54.7 HIP 34375 8.21
2026-10-11 00:00 07:06:46.92 +47:50:48.6 HIP 34375 8.80