| 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 |
0.998 |
| 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 |
+10.1458 |
-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) |
| 2026-06-01 00:00 |
12:54:46.75 |
+03:30:25.1 |
HIP 63090 |
14.04 |
| 2026-06-01 12:00 |
12:54:42.31 |
+03:29:57.0 |
HIP 63090 |
14.83 |
| 2026-06-02 00:00 |
12:54:37.94 |
+03:29:28.5 |
HIP 63090 |
15.65 |
| 2026-06-02 12:00 |
12:54:33.63 |
+03:28:59.5 |
HIP 63090 |
16.50 |
| 2026-06-03 00:00 |
12:54:29.39 |
+03:28:30.1 |
HIP 63090 |
17.38 |
| 2026-06-03 12:00 |
12:54:25.21 |
+03:28:00.2 |
HIP 63090 |
18.26 |
| 2026-06-04 00:00 |
12:54:21.10 |
+03:27:29.9 |
HIP 63090 |
19.16 |
| 2026-06-04 12:00 |
12:54:17.06 |
+03:26:59.2 |
HIP 63090 |
20.07 |
| 2026-06-05 00:00 |
12:54:13.08 |
+03:26:28.1 |
HIP 63090 |
20.98 |
| 2026-06-05 12:00 |
12:54:09.17 |
+03:25:56.6 |
HIP 63090 |
21.89 |
| 2026-06-06 00:00 |
12:54:05.33 |
+03:25:24.6 |
HIP 63090 |
22.80 |
| 2026-06-06 12:00 |
12:54:01.56 |
+03:24:52.2 |
HIP 63090 |
23.71 |
| 2026-06-07 00:00 |
12:53:57.85 |
+03:24:19.3 |
HIP 63090 |
24.62 |
| 2026-06-07 12:00 |
12:53:54.21 |
+03:23:46.1 |
HIP 63090 |
25.52 |
| 2026-06-08 00:00 |
12:53:50.64 |
+03:23:12.4 |
HIP 63090 |
26.42 |
| 2026-06-08 12:00 |
12:53:47.14 |
+03:22:38.3 |
HIP 63090 |
27.31 |
| 2026-06-09 00:00 |
12:53:43.71 |
+03:22:03.8 |
HIP 63090 |
28.20 |
| 2026-06-09 12:00 |
12:53:40.34 |
+03:21:28.8 |
HIP 63090 |
29.08 |
| 2026-06-10 00:00 |
12:53:37.04 |
+03:20:53.4 |
HIP 63056 |
29.54 |
| 2026-06-10 12:00 |
12:53:33.82 |
+03:20:17.6 |
HIP 63056 |
29.84 |
| 2026-06-11 00:00 |
12:53:30.66 |
+03:19:41.4 |
HIP 63056 |
30.14 |
| 2026-06-11 12:00 |
12:53:27.57 |
+03:19:04.8 |
HIP 63056 |
30.46 |
| 2026-06-12 00:00 |
12:53:24.55 |
+03:18:27.7 |
HIP 63056 |
30.79 |
| 2026-06-12 12:00 |
12:53:21.59 |
+03:17:50.3 |
HIP 62757 |
29.85 |
| 2026-06-13 00:00 |
12:53:18.71 |
+03:17:12.4 |
HIP 62757 |
28.92 |
| 2026-06-13 12:00 |
12:53:15.90 |
+03:16:34.1 |
HIP 62757 |
28.00 |
| 2026-06-14 00:00 |
12:53:13.16 |
+03:15:55.4 |
HIP 62757 |
27.09 |
| 2026-06-14 12:00 |
12:53:10.48 |
+03:15:16.2 |
HIP 62757 |
26.20 |
| 2026-06-15 00:00 |
12:53:07.88 |
+03:14:36.7 |
HIP 62757 |
25.32 |
| 2026-06-15 12:00 |
12:53:05.35 |
+03:13:56.7 |
HIP 62757 |
24.46 |
| 2026-06-16 00:00 |
12:53:02.88 |
+03:13:16.4 |
HIP 62757 |
23.62 |
| 2026-06-16 12:00 |
12:53:00.49 |
+03:12:35.6 |
HIP 62757 |
22.80 |
| 2026-06-17 00:00 |
12:52:58.17 |
+03:11:54.4 |
HIP 62757 |
21.99 |
| 2026-06-17 12:00 |
12:52:55.92 |
+03:11:12.8 |
HIP 62757 |
21.21 |
| 2026-06-18 00:00 |
12:52:53.74 |
+03:10:30.8 |
HIP 62757 |
20.45 |
| 2026-06-18 12:00 |
12:52:51.62 |
+03:09:48.5 |
HIP 62757 |
19.72 |
| 2026-06-19 00:00 |
12:52:49.58 |
+03:09:05.7 |
HIP 62757 |
19.01 |
| 2026-06-19 12:00 |
12:52:47.61 |
+03:08:22.5 |
HIP 62757 |
18.34 |
| 2026-06-20 00:00 |
12:52:45.71 |
+03:07:38.9 |
HIP 62757 |
17.69 |
| 2026-06-20 12:00 |
12:52:43.88 |
+03:06:54.9 |
HIP 62757 |
17.08 |
| 2026-06-21 00:00 |
12:52:42.12 |
+03:06:10.5 |
HIP 62757 |
16.51 |
| 2026-06-21 12:00 |
12:52:40.43 |
+03:05:25.8 |
HIP 62757 |
15.98 |
| 2026-06-22 00:00 |
12:52:38.80 |
+03:04:40.6 |
HIP 62757 |
15.50 |