| Parameter |
Value |
| Designation |
C/2020 A3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-06-28T20:34:35.627520Z |
| Orbit solution date (soln_date, UTC) |
2023-01-14T00:12:32Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
6.800 |
| K1 |
11.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-01-07T14:18:44.640000Z |
| Discovery magnitude (MPC) |
18.92 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-10-25.0000000 |
| e |
0.99890265 |
| q (au) |
5.766807 |
| a (au) |
5255.225488 |
| i (deg) |
146.700275 |
| Ω (om, deg) |
120.792469 |
| ω (w, deg) |
268.410013 |
| M (ma, deg) |
0.000306 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.943 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.943 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.501 |
| k |
1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
07:22:13.55 |
+30:48:45.2 |
HIP 35667 |
9.58 |
| 2026-07-29 12:00 |
07:22:19.53 |
+30:48:50.0 |
HIP 35667 |
10.71 |
| 2026-07-30 00:00 |
07:22:25.50 |
+30:48:54.9 |
HIP 35667 |
11.88 |
| 2026-07-30 12:00 |
07:22:31.45 |
+30:49:00.0 |
HIP 35667 |
13.06 |
| 2026-07-31 00:00 |
07:22:37.38 |
+30:49:05.2 |
HIP 35667 |
14.25 |
| 2026-07-31 12:00 |
07:22:43.29 |
+30:49:10.6 |
HIP 35667 |
15.45 |
| 2026-08-01 00:00 |
07:22:49.18 |
+30:49:16.1 |
HIP 35667 |
16.66 |
| 2026-08-01 12:00 |
07:22:55.06 |
+30:49:21.7 |
HIP 35667 |
17.87 |
| 2026-08-02 00:00 |
07:23:00.91 |
+30:49:27.5 |
HIP 35667 |
19.08 |
| 2026-08-02 12:00 |
07:23:06.74 |
+30:49:33.4 |
HIP 35931 |
18.92 |
| 2026-08-03 00:00 |
07:23:12.54 |
+30:49:39.5 |
HIP 35931 |
17.86 |
| 2026-08-03 12:00 |
07:23:18.33 |
+30:49:45.7 |
HIP 35931 |
16.84 |
| 2026-08-04 00:00 |
07:23:24.09 |
+30:49:52.0 |
HIP 35931 |
15.86 |
| 2026-08-04 12:00 |
07:23:29.84 |
+30:49:58.5 |
HIP 35948 |
14.75 |
| 2026-08-05 00:00 |
07:23:35.55 |
+30:50:05.2 |
HIP 35948 |
13.52 |
| 2026-08-05 12:00 |
07:23:41.25 |
+30:50:12.0 |
HIP 35948 |
12.29 |
| 2026-08-06 00:00 |
07:23:46.92 |
+30:50:18.9 |
HIP 35948 |
11.07 |
| 2026-08-06 12:00 |
07:23:52.56 |
+30:50:26.0 |
HIP 35948 |
9.85 |
| 2026-08-07 00:00 |
07:23:58.18 |
+30:50:33.2 |
HIP 35948 |
8.64 |
| 2026-08-07 12:00 |
07:24:03.78 |
+30:50:40.6 |
HIP 35948 |
7.43 |
| 2026-08-08 00:00 |
07:24:09.35 |
+30:50:48.2 |
HIP 35948 |
6.23 |
| 2026-08-08 12:00 |
07:24:14.89 |
+30:50:55.8 |
HIP 35948 |
5.03 |
| 2026-08-09 00:00 |
07:24:20.41 |
+30:51:03.7 |
HIP 35948 |
3.84 |
| 2026-08-09 12:00 |
07:24:25.89 |
+30:51:11.7 |
HIP 35948 |
2.66 |
| 2026-08-10 00:00 |
07:24:31.36 |
+30:51:19.8 |
HIP 35948 |
1.48 |
| 2026-08-10 12:00 |
07:24:36.79 |
+30:51:28.2 |
HIP 35948 |
0.32 |
| 2026-08-11 00:00 |
07:24:42.19 |
+30:51:36.6 |
HIP 35948 |
0.88 |
| 2026-08-11 12:00 |
07:24:47.57 |
+30:51:45.3 |
HIP 35948 |
2.04 |
| 2026-08-12 00:00 |
07:24:52.91 |
+30:51:54.0 |
HIP 35948 |
3.19 |
| 2026-08-12 12:00 |
07:24:58.23 |
+30:52:03.0 |
HIP 35948 |
4.34 |
| 2026-08-13 00:00 |
07:25:03.51 |
+30:52:12.1 |
HIP 35948 |
5.48 |
| 2026-08-13 12:00 |
07:25:08.76 |
+30:52:21.4 |
HIP 35948 |
6.62 |
| 2026-08-14 00:00 |
07:25:13.99 |
+30:52:30.8 |
HIP 35948 |
7.75 |
| 2026-08-14 12:00 |
07:25:19.17 |
+30:52:40.4 |
HIP 35948 |
8.88 |
| 2026-08-15 00:00 |
07:25:24.33 |
+30:52:50.1 |
HIP 35948 |
10.00 |
| 2026-08-15 12:00 |
07:25:29.46 |
+30:53:00.1 |
HIP 35948 |
11.11 |
| 2026-08-16 00:00 |
07:25:34.55 |
+30:53:10.1 |
HIP 35948 |
12.21 |
| 2026-08-16 12:00 |
07:25:39.60 |
+30:53:20.4 |
HIP 35948 |
13.31 |
| 2026-08-17 00:00 |
07:25:44.63 |
+30:53:30.8 |
HIP 35948 |
14.40 |
| 2026-08-17 12:00 |
07:25:49.61 |
+30:53:41.4 |
HIP 35948 |
15.49 |
| 2026-08-18 00:00 |
07:25:54.57 |
+30:53:52.2 |
HIP 35948 |
16.57 |
| 2026-08-18 12:00 |
07:25:59.49 |
+30:54:03.1 |
HIP 35948 |
17.64 |
| 2026-08-19 00:00 |
07:26:04.37 |
+30:54:14.2 |
HIP 35948 |
18.70 |