| 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 |
-0.500 |
| 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) |
| 2026-03-26 00:00 |
07:07:07.31 |
+31:00:23.5 |
HIP 34229 |
28.84 |
| 2026-03-26 12:00 |
07:07:04.40 |
+31:00:24.0 |
HIP 34229 |
28.46 |
| 2026-03-27 00:00 |
07:07:01.57 |
+31:00:24.4 |
HIP 34229 |
28.11 |
| 2026-03-27 12:00 |
07:06:58.81 |
+31:00:24.7 |
HIP 34229 |
27.78 |
| 2026-03-28 00:00 |
07:06:56.13 |
+31:00:24.9 |
HIP 34229 |
27.47 |
| 2026-03-28 12:00 |
07:06:53.53 |
+31:00:24.9 |
HIP 34229 |
27.17 |
| 2026-03-29 00:00 |
07:06:51.00 |
+31:00:24.8 |
HIP 34229 |
26.89 |
| 2026-03-29 12:00 |
07:06:48.54 |
+31:00:24.6 |
HIP 34229 |
26.63 |
| 2026-03-30 00:00 |
07:06:46.17 |
+31:00:24.2 |
HIP 34229 |
26.39 |
| 2026-03-30 12:00 |
07:06:43.87 |
+31:00:23.7 |
HIP 34229 |
26.17 |
| 2026-03-31 00:00 |
07:06:41.64 |
+31:00:23.1 |
HIP 34229 |
25.96 |
| 2026-03-31 12:00 |
07:06:39.49 |
+31:00:22.4 |
HIP 34229 |
25.77 |
| 2026-04-01 00:00 |
07:06:37.42 |
+31:00:21.6 |
HIP 34229 |
25.59 |
| 2026-04-01 12:00 |
07:06:35.42 |
+31:00:20.6 |
HIP 34229 |
25.43 |
| 2026-04-02 00:00 |
07:06:33.49 |
+31:00:19.6 |
HIP 34229 |
25.28 |
| 2026-04-02 12:00 |
07:06:31.64 |
+31:00:18.4 |
HIP 34229 |
25.15 |
| 2026-04-03 00:00 |
07:06:29.87 |
+31:00:17.1 |
HIP 34229 |
25.03 |
| 2026-04-03 12:00 |
07:06:28.17 |
+31:00:15.7 |
HIP 34229 |
24.92 |
| 2026-04-04 00:00 |
07:06:26.54 |
+31:00:14.2 |
HIP 34229 |
24.83 |
| 2026-04-04 12:00 |
07:06:24.99 |
+31:00:12.5 |
HIP 34229 |
24.74 |
| 2026-04-05 00:00 |
07:06:23.51 |
+31:00:10.8 |
HIP 34229 |
24.67 |
| 2026-04-05 12:00 |
07:06:22.11 |
+31:00:09.0 |
HIP 34229 |
24.60 |
| 2026-04-06 00:00 |
07:06:20.78 |
+31:00:07.0 |
HIP 34229 |
24.55 |
| 2026-04-06 12:00 |
07:06:19.53 |
+31:00:05.0 |
HIP 34229 |
24.51 |
| 2026-04-07 00:00 |
07:06:18.34 |
+31:00:02.9 |
HIP 34229 |
24.47 |
| 2026-04-07 12:00 |
07:06:17.24 |
+31:00:00.6 |
HIP 34229 |
24.44 |
| 2026-04-08 00:00 |
07:06:16.20 |
+30:59:58.3 |
HIP 34229 |
24.42 |
| 2026-04-08 12:00 |
07:06:15.24 |
+30:59:55.9 |
HIP 34229 |
24.41 |
| 2026-04-09 00:00 |
07:06:14.35 |
+30:59:53.3 |
HIP 34229 |
24.41 |
| 2026-04-09 12:00 |
07:06:13.53 |
+30:59:50.7 |
HIP 34229 |
24.41 |
| 2026-04-10 00:00 |
07:06:12.79 |
+30:59:48.0 |
HIP 34229 |
24.42 |
| 2026-04-10 12:00 |
07:06:12.12 |
+30:59:45.2 |
HIP 34229 |
24.43 |
| 2026-04-11 00:00 |
07:06:11.52 |
+30:59:42.3 |
HIP 34229 |
24.45 |
| 2026-04-11 12:00 |
07:06:11.00 |
+30:59:39.4 |
HIP 34229 |
24.47 |
| 2026-04-12 00:00 |
07:06:10.54 |
+30:59:36.3 |
HIP 34229 |
24.50 |
| 2026-04-12 12:00 |
07:06:10.16 |
+30:59:33.2 |
HIP 34229 |
24.54 |
| 2026-04-13 00:00 |
07:06:09.85 |
+30:59:29.9 |
HIP 34229 |
24.58 |
| 2026-04-13 12:00 |
07:06:09.61 |
+30:59:26.6 |
HIP 34229 |
24.62 |
| 2026-04-14 00:00 |
07:06:09.44 |
+30:59:23.2 |
HIP 34229 |
24.67 |
| 2026-04-14 12:00 |
07:06:09.34 |
+30:59:19.8 |
HIP 34229 |
24.72 |
| 2026-04-15 00:00 |
07:06:09.32 |
+30:59:16.2 |
HIP 34229 |
24.78 |
| 2026-04-15 12:00 |
07:06:09.36 |
+30:59:12.6 |
HIP 34229 |
24.84 |
| 2026-04-16 00:00 |
07:06:09.47 |
+30:59:08.9 |
HIP 34229 |
24.91 |