| Parameter |
Value |
| Designation |
C/2019 L3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-01-09T15:10:58.644480Z |
| Orbit solution date (soln_date, UTC) |
2025-06-26T10:12:44Z |
| Obs used |
6499 |
| NEO |
- |
| M1 |
5.500 |
| K1 |
8.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-06-10T13:29:16.886400Z |
| Discovery magnitude (MPC) |
18.18 o |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-10-10.0000000 |
| e |
1.00140528 |
| q (au) |
3.554493 |
| a (au) |
-2529.392057 |
| i (deg) |
48.363747 |
| Ω (om, deg) |
290.788887 |
| ω (w, deg) |
171.613705 |
| M (ma, deg) |
-0.000710 |
Magnitude
Scatter + Global Linear
$$
M_a = (1.726 + 4.845\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
1.726 |
| n |
4.845 |
| gf |
1.000 |
| gb |
-1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2019-06-10 |
2021-01-28 |
+0.5076 |
-0.218 |
| 2021-01-28 |
2022-01-09 |
+4.9638 |
-3.456 |
| 2022-01-09 |
2022-10-05 |
-9.9787 |
+4.854 |
| 2022-10-05 |
2025-05-29 |
+1.8997 |
-2.463 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
12:55:09.98 |
-56:48:57.8 |
HIP 63117 |
6.56 |
| 2026-07-29 12:00 |
12:55:19.26 |
-56:47:41.8 |
HIP 63117 |
5.73 |
| 2026-07-30 00:00 |
12:55:28.64 |
-56:46:26.6 |
HIP 63117 |
5.38 |
| 2026-07-30 12:00 |
12:55:38.12 |
-56:45:11.9 |
HIP 63117 |
5.59 |
| 2026-07-31 00:00 |
12:55:47.69 |
-56:43:57.9 |
HIP 63117 |
6.32 |
| 2026-07-31 12:00 |
12:55:57.36 |
-56:42:44.6 |
HIP 63117 |
7.40 |
| 2026-08-01 00:00 |
12:56:07.13 |
-56:41:31.9 |
HIP 63117 |
8.72 |
| 2026-08-01 12:00 |
12:56:16.99 |
-56:40:19.9 |
HIP 63117 |
10.19 |
| 2026-08-02 00:00 |
12:56:26.94 |
-56:39:08.6 |
HIP 63117 |
11.74 |
| 2026-08-02 12:00 |
12:56:36.99 |
-56:37:57.9 |
HIP 63117 |
13.35 |
| 2026-08-03 00:00 |
12:56:47.13 |
-56:36:47.9 |
HIP 63298 |
12.68 |
| 2026-08-03 12:00 |
12:56:57.37 |
-56:35:38.5 |
HIP 63298 |
11.42 |
| 2026-08-04 00:00 |
12:57:07.69 |
-56:34:29.8 |
HIP 63298 |
10.31 |
| 2026-08-04 12:00 |
12:57:18.11 |
-56:33:21.8 |
HIP 63298 |
9.41 |
| 2026-08-05 00:00 |
12:57:28.62 |
-56:32:14.5 |
HIP 63298 |
8.79 |
| 2026-08-05 12:00 |
12:57:39.22 |
-56:31:07.9 |
HIP 63298 |
8.50 |
| 2026-08-06 00:00 |
12:57:49.91 |
-56:30:01.9 |
HIP 63298 |
8.58 |
| 2026-08-06 12:00 |
12:58:00.69 |
-56:28:56.6 |
HIP 63298 |
9.03 |
| 2026-08-07 00:00 |
12:58:11.56 |
-56:27:52.0 |
HIP 63298 |
9.80 |
| 2026-08-07 12:00 |
12:58:22.51 |
-56:26:48.2 |
HIP 63298 |
10.82 |
| 2026-08-08 00:00 |
12:58:33.56 |
-56:25:45.0 |
HIP 63298 |
12.03 |
| 2026-08-08 12:00 |
12:58:44.69 |
-56:24:42.5 |
HIP 63230 |
13.05 |
| 2026-08-09 00:00 |
12:58:55.90 |
-56:23:40.7 |
HIP 63230 |
14.02 |
| 2026-08-09 12:00 |
12:59:07.21 |
-56:22:39.6 |
HIP 63230 |
15.17 |
| 2026-08-10 00:00 |
12:59:18.59 |
-56:21:39.2 |
HIP 63291 |
15.74 |
| 2026-08-10 12:00 |
12:59:30.07 |
-56:20:39.6 |
HIP 63291 |
15.98 |
| 2026-08-11 00:00 |
12:59:41.62 |
-56:19:40.6 |
HIP 63291 |
16.45 |
| 2026-08-11 12:00 |
12:59:53.26 |
-56:18:42.4 |
HIP 63291 |
17.13 |
| 2026-08-12 00:00 |
13:00:04.99 |
-56:17:44.9 |
HIP 63291 |
18.01 |
| 2026-08-12 12:00 |
13:00:16.79 |
-56:16:48.1 |
HIP 63291 |
19.04 |
| 2026-08-13 00:00 |
13:00:28.68 |
-56:15:52.0 |
HIP 63291 |
20.22 |
| 2026-08-13 12:00 |
13:00:40.64 |
-56:14:56.7 |
HIP 63424 |
21.26 |
| 2026-08-14 00:00 |
13:00:52.69 |
-56:14:02.1 |
HIP 63695 |
20.63 |
| 2026-08-14 12:00 |
13:01:04.82 |
-56:13:08.2 |
HIP 63695 |
18.74 |
| 2026-08-15 00:00 |
13:01:17.02 |
-56:12:15.0 |
HIP 63695 |
16.84 |
| 2026-08-15 12:00 |
13:01:29.31 |
-56:11:22.6 |
HIP 63695 |
14.94 |
| 2026-08-16 00:00 |
13:01:41.67 |
-56:10:30.9 |
HIP 63695 |
13.04 |
| 2026-08-16 12:00 |
13:01:54.10 |
-56:09:40.0 |
HIP 63695 |
11.14 |
| 2026-08-17 00:00 |
13:02:06.61 |
-56:08:49.8 |
HIP 63695 |
9.25 |
| 2026-08-17 12:00 |
13:02:19.20 |
-56:08:00.3 |
HIP 63695 |
7.36 |
| 2026-08-18 00:00 |
13:02:31.86 |
-56:07:11.6 |
HIP 63695 |
5.49 |
| 2026-08-18 12:00 |
13:02:44.60 |
-56:06:23.6 |
HIP 63695 |
3.70 |
| 2026-08-19 00:00 |
13:02:57.41 |
-56:05:36.3 |
HIP 63695 |
2.17 |