C/2020 P3 (ATLAS)
| Parameter |
Value |
| Designation |
C/2020 P3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-04-20T20:06:04.121280Z |
| Orbit solution date (soln_date, UTC) |
2024-04-29T13:12:18Z |
| Obs used |
698 |
| NEO |
- |
| M1 |
5.800 |
| K1 |
10.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-08-09T13:40:41.433600Z |
| Discovery magnitude (MPC) |
19.01 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-07-14.0000000 |
| e |
0.99914404 |
| q (au) |
6.812376 |
| a (au) |
7958.786111 |
| i (deg) |
61.884995 |
| Ω (om, deg) |
19.484342 |
| ω (w, deg) |
82.246067 |
| M (ma, deg) |
0.000117 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.781 + 5.487\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.781 |
| n |
5.487 |
| gf |
1.000 |
| gb |
-0.906 |
| k |
0.800 |
| δ90 |
10.000 |
| 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 |
| 2021-05-24 |
2024-04-12 |
+10.1462 |
-9.061 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
13:22:26.87 |
+03:05:34.7 |
HIP 65192 |
19.00 |
| 2026-02-03 12:00 |
13:22:23.67 |
+03:05:40.9 |
HIP 65192 |
18.57 |
| 2026-02-04 00:00 |
13:22:20.39 |
+03:05:47.4 |
HIP 65192 |
18.15 |
| 2026-02-04 12:00 |
13:22:17.04 |
+03:05:54.3 |
HIP 65192 |
17.76 |
| 2026-02-05 00:00 |
13:22:13.60 |
+03:06:01.5 |
HIP 65192 |
17.39 |
| 2026-02-05 12:00 |
13:22:10.10 |
+03:06:09.1 |
HIP 65192 |
17.05 |
| 2026-02-06 00:00 |
13:22:06.51 |
+03:06:16.9 |
HIP 65192 |
16.76 |
| 2026-02-06 12:00 |
13:22:02.86 |
+03:06:25.1 |
HIP 65192 |
16.50 |
| 2026-02-07 00:00 |
13:21:59.12 |
+03:06:33.6 |
HIP 65192 |
16.29 |
| 2026-02-07 12:00 |
13:21:55.32 |
+03:06:42.4 |
HIP 65192 |
16.13 |
| 2026-02-08 00:00 |
13:21:51.43 |
+03:06:51.6 |
HIP 65192 |
16.03 |
| 2026-02-08 12:00 |
13:21:47.48 |
+03:07:01.0 |
HIP 65192 |
15.99 |
| 2026-02-09 00:00 |
13:21:43.44 |
+03:07:10.8 |
HIP 65192 |
16.02 |
| 2026-02-09 12:00 |
13:21:39.34 |
+03:07:20.8 |
HIP 65192 |
16.12 |
| 2026-02-10 00:00 |
13:21:35.16 |
+03:07:31.2 |
HIP 65192 |
16.28 |
| 2026-02-10 12:00 |
13:21:30.91 |
+03:07:41.8 |
HIP 65192 |
16.52 |
| 2026-02-11 00:00 |
13:21:26.58 |
+03:07:52.8 |
HIP 65119 |
15.96 |
| 2026-02-11 12:00 |
13:21:22.19 |
+03:08:04.0 |
HIP 65119 |
15.35 |
| 2026-02-12 00:00 |
13:21:17.72 |
+03:08:15.5 |
HIP 65119 |
14.79 |
| 2026-02-12 12:00 |
13:21:13.17 |
+03:08:27.3 |
HIP 65119 |
14.29 |
| 2026-02-13 00:00 |
13:21:08.56 |
+03:08:39.4 |
HIP 65119 |
13.86 |
| 2026-02-13 12:00 |
13:21:03.87 |
+03:08:51.7 |
HIP 65119 |
13.52 |
| 2026-02-14 00:00 |
13:20:59.11 |
+03:09:04.4 |
HIP 65119 |
13.27 |
| 2026-02-14 12:00 |
13:20:54.29 |
+03:09:17.2 |
HIP 65067 |
12.69 |
| 2026-02-15 00:00 |
13:20:49.39 |
+03:09:30.4 |
HIP 65067 |
11.62 |
| 2026-02-15 12:00 |
13:20:44.42 |
+03:09:43.8 |
HIP 65067 |
10.57 |
| 2026-02-16 00:00 |
13:20:39.38 |
+03:09:57.4 |
HIP 65067 |
9.55 |
| 2026-02-16 12:00 |
13:20:34.27 |
+03:10:11.3 |
HIP 65067 |
8.59 |
| 2026-02-17 00:00 |
13:20:29.10 |
+03:10:25.4 |
HIP 65067 |
7.72 |
| 2026-02-17 12:00 |
13:20:23.85 |
+03:10:39.8 |
HIP 65067 |
6.98 |
| 2026-02-18 00:00 |
13:20:18.54 |
+03:10:54.4 |
HIP 65067 |
6.42 |
| 2026-02-18 12:00 |
13:20:13.16 |
+03:11:09.2 |
HIP 65067 |
6.11 |
| 2026-02-19 00:00 |
13:20:07.71 |
+03:11:24.2 |
HIP 65067 |
6.10 |
| 2026-02-19 12:00 |
13:20:02.19 |
+03:11:39.5 |
HIP 65067 |
6.41 |
| 2026-02-20 00:00 |
13:19:56.61 |
+03:11:55.0 |
HIP 65067 |
6.99 |
| 2026-02-20 12:00 |
13:19:50.97 |
+03:12:10.7 |
HIP 65067 |
7.80 |
| 2026-02-21 00:00 |
13:19:45.26 |
+03:12:26.5 |
HIP 65067 |
8.78 |
| 2026-02-21 12:00 |
13:19:39.48 |
+03:12:42.6 |
HIP 65067 |
9.89 |
| 2026-02-22 00:00 |
13:19:33.64 |
+03:12:58.9 |
HIP 65067 |
11.10 |
| 2026-02-22 12:00 |
13:19:27.74 |
+03:13:15.4 |
HIP 65067 |
12.38 |
| 2026-02-23 00:00 |
13:19:21.77 |
+03:13:32.0 |
HIP 65067 |
13.72 |
| 2026-02-23 12:00 |
13:19:15.74 |
+03:13:48.8 |
HIP 65067 |
15.11 |
| 2026-02-24 00:00 |
13:19:09.65 |
+03:14:05.8 |
HIP 65067 |
16.54 |