C/2019 F1 (ATLAS-Africano)

Metadata

Parameter Value
Designation C/2019 F1 (ATLAS-Africano)
Type C
Perihelion (tp_cal, UTC) 2021-06-22T19:03:30.551040Z
Orbit solution date (soln_date, UTC) 2024-04-13T16:42:29Z
Obs used 1964
NEO -
M1 9.600
K1 5.500
PC -
Discovery observation (MPC, UTC) 2019-03-29T10:03:21.600000Z
Discovery magnitude (MPC) 18.40 G
Discovery observatory (MPC) G96 · University of Arizona Mt. Lemmon Survey
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2020-10-21.0000000
e 1.00348898
q (au) 3.595914
a (au) -1030.647736
i (deg) 54.175708
Ω (om, deg) 38.726260
ω (w, deg) 251.113825
M (ma, deg) -0.007292

Magnitude

C/2019 F1 (ATLAS-Africano) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (8.031 + 2.895\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 8.031
n 2.895
gf 0.914
gb -0.906
k 1.000
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

Residuals (Piecewise)

$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$

Start (UTC) End (UTC) a b
2019-02-08 2019-10-14 +8.8747 -7.840
2019-10-14 2020-05-26 -6.5457 +4.593
2020-05-26 2021-06-18 -3.0290 +1.838
2021-06-27 2022-08-28 +0.5643 +0.081
2022-08-28 2022-12-25 -8.8752 +7.089
2022-12-25 2024-01-31 +9.9762 -7.455

log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-06-01 00:00 02:44:53.07 +23:22:01.5 HIP 12830 0.93
2026-06-01 12:00 02:45:01.03 +23:23:03.2 HIP 12830 1.33
2026-06-02 00:00 02:45:08.96 +23:24:04.8 HIP 12830 3.38
2026-06-02 12:00 02:45:16.85 +23:25:06.4 HIP 12830 5.45
2026-06-03 00:00 02:45:24.72 +23:26:07.9 HIP 12830 7.52
2026-06-03 12:00 02:45:32.56 +23:27:09.4 HIP 12830 9.59
2026-06-04 00:00 02:45:40.36 +23:28:10.9 HIP 12830 11.65
2026-06-04 12:00 02:45:48.14 +23:29:12.3 HIP 12830 13.70
2026-06-05 00:00 02:45:55.88 +23:30:13.6 HIP 12830 15.75
2026-06-05 12:00 02:46:03.59 +23:31:14.9 HIP 12830 17.79
2026-06-06 00:00 02:46:11.27 +23:32:16.2 HIP 13035 19.07
2026-06-06 12:00 02:46:18.91 +23:33:17.4 HIP 13035 17.09
2026-06-07 00:00 02:46:26.53 +23:34:18.6 HIP 13035 15.13
2026-06-07 12:00 02:46:34.10 +23:35:19.6 HIP 13035 13.20
2026-06-08 00:00 02:46:41.65 +23:36:20.7 HIP 13035 11.31
2026-06-08 12:00 02:46:49.16 +23:37:21.7 HIP 13035 9.47
2026-06-09 00:00 02:46:56.63 +23:38:22.6 HIP 13035 7.73
2026-06-09 12:00 02:47:04.07 +23:39:23.4 HIP 13035 6.14
2026-06-10 00:00 02:47:11.47 +23:40:24.2 HIP 13035 4.85
2026-06-10 12:00 02:47:18.84 +23:41:24.9 HIP 13035 4.16
2026-06-11 00:00 02:47:26.17 +23:42:25.6 HIP 13035 4.33
2026-06-11 12:00 02:47:33.46 +23:43:26.2 HIP 13035 5.29
2026-06-12 00:00 02:47:40.72 +23:44:26.7 HIP 13035 6.68
2026-06-12 12:00 02:47:47.93 +23:45:27.1 HIP 13035 8.29
2026-06-13 00:00 02:47:55.11 +23:46:27.5 HIP 13035 10.02
2026-06-13 12:00 02:48:02.25 +23:47:27.8 HIP 13035 11.79
2026-06-14 00:00 02:48:09.35 +23:48:28.0 HIP 13035 13.60
2026-06-14 12:00 02:48:16.41 +23:49:28.1 HIP 13035 15.43
2026-06-15 00:00 02:48:23.42 +23:50:28.1 HIP 13035 17.26
2026-06-15 12:00 02:48:30.40 +23:51:28.1 HIP 13035 19.10
2026-06-16 00:00 02:48:37.33 +23:52:27.9 HIP 13035 20.94
2026-06-16 12:00 02:48:44.23 +23:53:27.7 HIP 13035 22.77
2026-06-17 00:00 02:48:51.08 +23:54:27.4 HIP 13035 24.61
2026-06-17 12:00 02:48:57.88 +23:55:27.0 HIP 13242 25.01
2026-06-18 00:00 02:49:04.65 +23:56:26.5 HIP 13242 24.41
2026-06-18 12:00 02:49:11.37 +23:57:25.9 HIP 13242 23.94
2026-06-19 00:00 02:49:18.04 +23:58:25.2 HIP 13242 23.61
2026-06-19 12:00 02:49:24.68 +23:59:24.4 HIP 13242 23.42
2026-06-20 00:00 02:49:31.26 +24:00:23.5 HIP 13242 23.38
2026-06-20 12:00 02:49:37.80 +24:01:22.5 HIP 13242 23.47
2026-06-21 00:00 02:49:44.30 +24:02:21.4 HIP 13242 23.71
2026-06-21 12:00 02:49:50.75 +24:03:20.2 HIP 13277 23.72
2026-06-22 00:00 02:49:57.15 +24:04:18.9 HIP 13277 23.67