| 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 |
0.999 |
| 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) |
| 2026-03-26 00:00 |
13:19:13.14 |
-62:19:51.5 |
HIP 64969 |
3.53 |
| 2026-03-26 12:00 |
13:18:58.16 |
-62:20:00.1 |
HIP 64969 |
2.94 |
| 2026-03-27 00:00 |
13:18:43.13 |
-62:20:07.5 |
HIP 64969 |
3.32 |
| 2026-03-27 12:00 |
13:18:28.06 |
-62:20:13.8 |
HIP 64969 |
4.43 |
| 2026-03-28 00:00 |
13:18:12.93 |
-62:20:18.8 |
HIP 64969 |
5.88 |
| 2026-03-28 12:00 |
13:17:57.76 |
-62:20:22.6 |
HIP 64969 |
7.47 |
| 2026-03-29 00:00 |
13:17:42.54 |
-62:20:25.2 |
HIP 64969 |
9.14 |
| 2026-03-29 12:00 |
13:17:27.28 |
-62:20:26.6 |
HIP 64969 |
10.85 |
| 2026-03-30 00:00 |
13:17:11.99 |
-62:20:26.7 |
HIP 64969 |
12.58 |
| 2026-03-30 12:00 |
13:16:56.66 |
-62:20:25.7 |
HIP 64969 |
14.33 |
| 2026-03-31 00:00 |
13:16:41.29 |
-62:20:23.5 |
HIP 64737 |
15.23 |
| 2026-03-31 12:00 |
13:16:25.88 |
-62:20:20.0 |
HIP 64737 |
14.89 |
| 2026-04-01 00:00 |
13:16:10.45 |
-62:20:15.4 |
HIP 64737 |
14.78 |
| 2026-04-01 12:00 |
13:15:54.99 |
-62:20:09.5 |
HIP 64737 |
14.91 |
| 2026-04-02 00:00 |
13:15:39.50 |
-62:20:02.5 |
HIP 64737 |
15.27 |
| 2026-04-02 12:00 |
13:15:23.99 |
-62:19:54.2 |
HIP 64737 |
15.84 |
| 2026-04-03 00:00 |
13:15:08.45 |
-62:19:44.8 |
HIP 64702 |
16.56 |
| 2026-04-03 12:00 |
13:14:52.89 |
-62:19:34.1 |
HIP 64702 |
16.89 |
| 2026-04-04 00:00 |
13:14:37.31 |
-62:19:22.2 |
HIP 64702 |
17.38 |
| 2026-04-04 12:00 |
13:14:21.72 |
-62:19:09.1 |
HIP 64702 |
18.03 |
| 2026-04-05 00:00 |
13:14:06.11 |
-62:18:54.9 |
HIP 64702 |
18.82 |
| 2026-04-05 12:00 |
13:13:50.49 |
-62:18:39.4 |
HIP 64702 |
19.74 |
| 2026-04-06 00:00 |
13:13:34.86 |
-62:18:22.7 |
HIP 64702 |
20.77 |
| 2026-04-06 12:00 |
13:13:19.22 |
-62:18:04.9 |
HIP 64322 |
20.77 |
| 2026-04-07 00:00 |
13:13:03.58 |
-62:17:45.8 |
HIP 64322 |
19.16 |
| 2026-04-07 12:00 |
13:12:47.93 |
-62:17:25.6 |
HIP 64322 |
17.59 |
| 2026-04-08 00:00 |
13:12:32.28 |
-62:17:04.1 |
HIP 64322 |
16.05 |
| 2026-04-08 12:00 |
13:12:16.63 |
-62:16:41.5 |
HIP 64322 |
14.58 |
| 2026-04-09 00:00 |
13:12:00.98 |
-62:16:17.7 |
HIP 64322 |
13.19 |
| 2026-04-09 12:00 |
13:11:45.34 |
-62:15:52.7 |
HIP 64322 |
11.91 |
| 2026-04-10 00:00 |
13:11:29.70 |
-62:15:26.5 |
HIP 64322 |
10.79 |
| 2026-04-10 12:00 |
13:11:14.07 |
-62:14:59.1 |
HIP 64322 |
9.88 |
| 2026-04-11 00:00 |
13:10:58.46 |
-62:14:30.6 |
HIP 64322 |
9.25 |
| 2026-04-11 12:00 |
13:10:42.85 |
-62:14:00.9 |
HIP 64322 |
8.96 |
| 2026-04-12 00:00 |
13:10:27.26 |
-62:13:30.0 |
HIP 64322 |
9.04 |
| 2026-04-12 12:00 |
13:10:11.69 |
-62:12:57.9 |
HIP 64322 |
9.48 |
| 2026-04-13 00:00 |
13:09:56.14 |
-62:12:24.7 |
HIP 64322 |
10.25 |
| 2026-04-13 12:00 |
13:09:40.61 |
-62:11:50.4 |
HIP 64322 |
11.28 |
| 2026-04-14 00:00 |
13:09:25.10 |
-62:11:14.8 |
HIP 64322 |
12.50 |
| 2026-04-14 12:00 |
13:09:09.62 |
-62:10:38.2 |
HIP 64322 |
13.87 |
| 2026-04-15 00:00 |
13:08:54.17 |
-62:10:00.3 |
HIP 63994 |
14.91 |
| 2026-04-15 12:00 |
13:08:38.75 |
-62:09:21.4 |
HIP 63994 |
13.01 |
| 2026-04-16 00:00 |
13:08:23.36 |
-62:08:41.3 |
HIP 63994 |
11.12 |