| 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
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) |
| 2026-07-29 00:00 |
02:55:17.00 |
+25:09:52.1 |
HIP 13607 |
25.67 |
| 2026-07-29 12:00 |
02:55:18.93 |
+25:10:38.1 |
HIP 13607 |
26.42 |
| 2026-07-30 00:00 |
02:55:20.79 |
+25:11:23.9 |
HIP 13607 |
27.18 |
| 2026-07-30 12:00 |
02:55:22.57 |
+25:12:09.5 |
HIP 13607 |
27.95 |
| 2026-07-31 00:00 |
02:55:24.29 |
+25:12:54.8 |
HIP 13607 |
28.71 |
| 2026-07-31 12:00 |
02:55:25.94 |
+25:13:39.9 |
HIP 13607 |
29.48 |
| 2026-08-01 00:00 |
02:55:27.51 |
+25:14:24.8 |
HIP 13607 |
30.24 |
| 2026-08-01 12:00 |
02:55:29.01 |
+25:15:09.5 |
HIP 13607 |
31.00 |
| 2026-08-02 00:00 |
02:55:30.44 |
+25:15:53.9 |
HIP 13607 |
31.76 |
| 2026-08-02 12:00 |
02:55:31.80 |
+25:16:38.0 |
HIP 13607 |
32.52 |
| 2026-08-03 00:00 |
02:55:33.08 |
+25:17:21.9 |
HIP 13607 |
33.27 |
| 2026-08-03 12:00 |
02:55:34.30 |
+25:18:05.6 |
HIP 13607 |
34.02 |
| 2026-08-04 00:00 |
02:55:35.44 |
+25:18:49.0 |
HIP 13607 |
34.77 |
| 2026-08-04 12:00 |
02:55:36.51 |
+25:19:32.2 |
HIP 13607 |
35.51 |
| 2026-08-05 00:00 |
02:55:37.50 |
+25:20:15.1 |
HIP 13607 |
36.24 |
| 2026-08-05 12:00 |
02:55:38.43 |
+25:20:57.8 |
HIP 13607 |
36.97 |
| 2026-08-06 00:00 |
02:55:39.27 |
+25:21:40.2 |
HIP 13607 |
37.69 |
| 2026-08-06 12:00 |
02:55:40.05 |
+25:22:22.3 |
HIP 13607 |
38.41 |
| 2026-08-07 00:00 |
02:55:40.75 |
+25:23:04.2 |
HIP 13607 |
39.12 |
| 2026-08-07 12:00 |
02:55:41.38 |
+25:23:45.9 |
HIP 13607 |
39.83 |
| 2026-08-08 00:00 |
02:55:41.93 |
+25:24:27.2 |
HIP 13607 |
40.53 |
| 2026-08-08 12:00 |
02:55:42.41 |
+25:25:08.3 |
HIP 13672 |
40.62 |
| 2026-08-09 00:00 |
02:55:42.81 |
+25:25:49.2 |
HIP 13672 |
39.93 |
| 2026-08-09 12:00 |
02:55:43.14 |
+25:26:29.8 |
HIP 13672 |
39.25 |
| 2026-08-10 00:00 |
02:55:43.40 |
+25:27:10.1 |
HIP 13672 |
38.58 |
| 2026-08-10 12:00 |
02:55:43.57 |
+25:27:50.1 |
HIP 13672 |
37.91 |
| 2026-08-11 00:00 |
02:55:43.68 |
+25:28:29.9 |
HIP 13672 |
37.25 |
| 2026-08-11 12:00 |
02:55:43.71 |
+25:29:09.4 |
HIP 13672 |
36.60 |
| 2026-08-12 00:00 |
02:55:43.66 |
+25:29:48.6 |
HIP 13672 |
35.95 |
| 2026-08-12 12:00 |
02:55:43.54 |
+25:30:27.5 |
HIP 13672 |
35.31 |
| 2026-08-13 00:00 |
02:55:43.34 |
+25:31:06.1 |
HIP 13672 |
34.68 |
| 2026-08-13 12:00 |
02:55:43.06 |
+25:31:44.5 |
HIP 13672 |
34.06 |
| 2026-08-14 00:00 |
02:55:42.71 |
+25:32:22.6 |
HIP 13672 |
33.44 |
| 2026-08-14 12:00 |
02:55:42.29 |
+25:33:00.4 |
HIP 13672 |
32.83 |
| 2026-08-15 00:00 |
02:55:41.78 |
+25:33:37.9 |
HIP 13672 |
32.23 |
| 2026-08-15 12:00 |
02:55:41.21 |
+25:34:15.1 |
HIP 13672 |
31.64 |
| 2026-08-16 00:00 |
02:55:40.55 |
+25:34:52.1 |
HIP 13672 |
31.06 |
| 2026-08-16 12:00 |
02:55:39.82 |
+25:35:28.7 |
HIP 13672 |
30.49 |
| 2026-08-17 00:00 |
02:55:39.01 |
+25:36:05.1 |
HIP 13672 |
29.93 |
| 2026-08-17 12:00 |
02:55:38.13 |
+25:36:41.1 |
HIP 13672 |
29.38 |
| 2026-08-18 00:00 |
02:55:37.17 |
+25:37:16.9 |
HIP 13672 |
28.84 |
| 2026-08-18 12:00 |
02:55:36.14 |
+25:37:52.4 |
HIP 13672 |
28.32 |
| 2026-08-19 00:00 |
02:55:35.03 |
+25:38:27.5 |
HIP 13672 |
27.80 |