| Parameter |
Value |
| Designation |
C/2020 F2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-07-15T21:34:18.912000Z |
| Orbit solution date (soln_date, UTC) |
2026-03-07T14:42:52Z |
| Obs used |
1649 |
| NEO |
- |
| M1 |
6.300 |
| K1 |
7.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-04-08.0000000 |
| e |
1.00484187 |
| q (au) |
8.817057 |
| a (au) |
-1821.002957 |
| i (deg) |
163.583705 |
| Ω (om, deg) |
250.268049 |
| ω (w, deg) |
48.361233 |
| M (ma, deg) |
-0.001254 |
Magnitude
Scatter + Global Linear
$$
M_a = (-1.805 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-1.805 |
| n |
6.000 |
| gf |
0.903 |
| gb |
-0.928 |
| k |
1.000 |
| δ90 |
3.436 |
| 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 |
| 2019-05-27 |
2022-07-14 |
+9.9413 |
-9.588 |
| 2022-07-16 |
2025-11-20 |
+12.4304 |
-11.931 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
09:33:35.73 |
+30:49:03.0 |
HIP 46868 |
16.57 |
| 2026-05-12 12:00 |
09:33:31.81 |
+30:48:32.6 |
HIP 46868 |
15.75 |
| 2026-05-13 00:00 |
09:33:27.98 |
+30:48:01.9 |
HIP 46868 |
14.96 |
| 2026-05-13 12:00 |
09:33:24.26 |
+30:47:30.8 |
HIP 46868 |
14.19 |
| 2026-05-14 00:00 |
09:33:20.64 |
+30:46:59.4 |
HIP 46868 |
13.45 |
| 2026-05-14 12:00 |
09:33:17.11 |
+30:46:27.7 |
HIP 46868 |
12.73 |
| 2026-05-15 00:00 |
09:33:13.69 |
+30:45:55.6 |
HIP 46868 |
12.03 |
| 2026-05-15 12:00 |
09:33:10.36 |
+30:45:23.2 |
HIP 46868 |
11.37 |
| 2026-05-16 00:00 |
09:33:07.13 |
+30:44:50.6 |
HIP 46868 |
10.74 |
| 2026-05-16 12:00 |
09:33:04.00 |
+30:44:17.6 |
HIP 46868 |
10.14 |
| 2026-05-17 00:00 |
09:33:00.97 |
+30:43:44.3 |
HIP 46868 |
9.57 |
| 2026-05-17 12:00 |
09:32:58.03 |
+30:43:10.6 |
HIP 46868 |
9.05 |
| 2026-05-18 00:00 |
09:32:55.20 |
+30:42:36.7 |
HIP 46868 |
8.57 |
| 2026-05-18 12:00 |
09:32:52.45 |
+30:42:02.6 |
HIP 46868 |
8.13 |
| 2026-05-19 00:00 |
09:32:49.81 |
+30:41:28.1 |
HIP 46868 |
7.75 |
| 2026-05-19 12:00 |
09:32:47.26 |
+30:40:53.3 |
HIP 46868 |
7.42 |
| 2026-05-20 00:00 |
09:32:44.81 |
+30:40:18.3 |
HIP 46868 |
7.15 |
| 2026-05-20 12:00 |
09:32:42.45 |
+30:39:43.0 |
HIP 46868 |
6.95 |
| 2026-05-21 00:00 |
09:32:40.18 |
+30:39:07.4 |
HIP 46868 |
6.81 |
| 2026-05-21 12:00 |
09:32:38.01 |
+30:38:31.5 |
HIP 46868 |
6.74 |
| 2026-05-22 00:00 |
09:32:35.93 |
+30:37:55.4 |
HIP 46868 |
6.73 |
| 2026-05-22 12:00 |
09:32:33.95 |
+30:37:19.1 |
HIP 46868 |
6.79 |
| 2026-05-23 00:00 |
09:32:32.06 |
+30:36:42.5 |
HIP 46868 |
6.90 |
| 2026-05-23 12:00 |
09:32:30.26 |
+30:36:05.6 |
HIP 46868 |
7.07 |
| 2026-05-24 00:00 |
09:32:28.55 |
+30:35:28.5 |
HIP 46868 |
7.29 |
| 2026-05-24 12:00 |
09:32:26.94 |
+30:34:51.2 |
HIP 46868 |
7.55 |
| 2026-05-25 00:00 |
09:32:25.41 |
+30:34:13.7 |
HIP 46868 |
7.85 |
| 2026-05-25 12:00 |
09:32:23.97 |
+30:33:35.9 |
HIP 46868 |
8.18 |
| 2026-05-26 00:00 |
09:32:22.63 |
+30:32:57.9 |
HIP 46868 |
8.53 |
| 2026-05-26 12:00 |
09:32:21.37 |
+30:32:19.6 |
HIP 46868 |
8.91 |
| 2026-05-27 00:00 |
09:32:20.20 |
+30:31:41.2 |
HIP 46868 |
9.31 |
| 2026-05-27 12:00 |
09:32:19.12 |
+30:31:02.5 |
HIP 46868 |
9.72 |
| 2026-05-28 00:00 |
09:32:18.13 |
+30:30:23.7 |
HIP 46868 |
10.14 |
| 2026-05-28 12:00 |
09:32:17.23 |
+30:29:44.6 |
HIP 46868 |
10.58 |
| 2026-05-29 00:00 |
09:32:16.41 |
+30:29:05.3 |
HIP 46868 |
11.03 |
| 2026-05-29 12:00 |
09:32:15.68 |
+30:28:25.9 |
HIP 46868 |
11.48 |
| 2026-05-30 00:00 |
09:32:15.03 |
+30:27:46.2 |
HIP 46868 |
11.94 |
| 2026-05-30 12:00 |
09:32:14.47 |
+30:27:06.4 |
HIP 46868 |
12.41 |
| 2026-05-31 00:00 |
09:32:14.00 |
+30:26:26.3 |
HIP 46868 |
12.88 |
| 2026-05-31 12:00 |
09:32:13.61 |
+30:25:46.1 |
HIP 46868 |
13.36 |
| 2026-06-01 00:00 |
09:32:13.30 |
+30:25:05.7 |
HIP 46868 |
13.85 |
| 2026-06-01 12:00 |
09:32:13.08 |
+30:24:25.2 |
HIP 46868 |
14.33 |
| 2026-06-02 00:00 |
09:32:12.94 |
+30:23:44.4 |
HIP 46868 |
14.82 |