C/2019 L3 (ATLAS)
| 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 |
-9.9753 |
+4.852 |
| 2022-10-05 |
2025-05-29 |
+1.8996 |
-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) |
| 2026-02-03 00:00 |
13:35:04.09 |
-60:32:28.9 |
HIP 66296 |
23.05 |
| 2026-02-03 12:00 |
13:35:02.18 |
-60:34:14.2 |
HIP 66010 |
23.93 |
| 2026-02-04 00:00 |
13:35:00.10 |
-60:35:58.8 |
HIP 66010 |
24.32 |
| 2026-02-04 12:00 |
13:34:57.86 |
-60:37:42.9 |
HIP 66010 |
24.80 |
| 2026-02-05 00:00 |
13:34:55.45 |
-60:39:26.4 |
HIP 66010 |
25.38 |
| 2026-02-05 12:00 |
13:34:52.88 |
-60:41:09.3 |
HIP 66010 |
26.04 |
| 2026-02-06 00:00 |
13:34:50.15 |
-60:42:51.6 |
HIP 66010 |
26.77 |
| 2026-02-06 12:00 |
13:34:47.26 |
-60:44:33.3 |
HIP 66010 |
27.58 |
| 2026-02-07 00:00 |
13:34:44.20 |
-60:46:14.4 |
HIP 66010 |
28.44 |
| 2026-02-07 12:00 |
13:34:40.98 |
-60:47:54.9 |
HIP 66010 |
29.36 |
| 2026-02-08 00:00 |
13:34:37.60 |
-60:49:34.7 |
HIP 66010 |
30.33 |
| 2026-02-08 12:00 |
13:34:34.05 |
-60:51:13.9 |
HIP 66010 |
31.35 |
| 2026-02-09 00:00 |
13:34:30.34 |
-60:52:52.5 |
HIP 66010 |
32.40 |
| 2026-02-09 12:00 |
13:34:26.47 |
-60:54:30.3 |
HIP 66010 |
33.48 |
| 2026-02-10 00:00 |
13:34:22.44 |
-60:56:07.6 |
HIP 66010 |
34.60 |
| 2026-02-10 12:00 |
13:34:18.24 |
-60:57:44.1 |
HIP 66010 |
35.74 |
| 2026-02-11 00:00 |
13:34:13.88 |
-60:59:20.0 |
HIP 65818 |
35.95 |
| 2026-02-11 12:00 |
13:34:09.36 |
-61:00:55.1 |
HIP 65818 |
34.90 |
| 2026-02-12 00:00 |
13:34:04.67 |
-61:02:29.6 |
HIP 65818 |
33.90 |
| 2026-02-12 12:00 |
13:33:59.82 |
-61:04:03.4 |
HIP 65818 |
32.93 |
| 2026-02-13 00:00 |
13:33:54.81 |
-61:05:36.4 |
HIP 66172 |
31.85 |
| 2026-02-13 12:00 |
13:33:49.64 |
-61:07:08.7 |
HIP 66172 |
30.31 |
| 2026-02-14 00:00 |
13:33:44.31 |
-61:08:40.3 |
HIP 66172 |
28.79 |
| 2026-02-14 12:00 |
13:33:38.82 |
-61:10:11.1 |
HIP 66172 |
27.30 |
| 2026-02-15 00:00 |
13:33:33.17 |
-61:11:41.2 |
HIP 66172 |
25.84 |
| 2026-02-15 12:00 |
13:33:27.36 |
-61:13:10.5 |
HIP 66172 |
24.42 |
| 2026-02-16 00:00 |
13:33:21.39 |
-61:14:39.0 |
HIP 66172 |
23.04 |
| 2026-02-16 12:00 |
13:33:15.26 |
-61:16:06.7 |
HIP 66172 |
21.72 |
| 2026-02-17 00:00 |
13:33:08.97 |
-61:17:33.7 |
HIP 66172 |
20.46 |
| 2026-02-17 12:00 |
13:33:02.52 |
-61:18:59.9 |
HIP 65970 |
19.17 |
| 2026-02-18 00:00 |
13:32:55.92 |
-61:20:25.2 |
HIP 65970 |
17.55 |
| 2026-02-18 12:00 |
13:32:49.15 |
-61:21:49.7 |
HIP 65970 |
15.93 |
| 2026-02-19 00:00 |
13:32:42.24 |
-61:23:13.4 |
HIP 65970 |
14.31 |
| 2026-02-19 12:00 |
13:32:35.16 |
-61:24:36.3 |
HIP 65970 |
12.69 |
| 2026-02-20 00:00 |
13:32:27.94 |
-61:25:58.3 |
HIP 65970 |
11.08 |
| 2026-02-20 12:00 |
13:32:20.56 |
-61:27:19.5 |
HIP 65970 |
9.47 |
| 2026-02-21 00:00 |
13:32:13.02 |
-61:28:39.8 |
HIP 65970 |
7.85 |
| 2026-02-21 12:00 |
13:32:05.33 |
-61:29:59.3 |
HIP 65970 |
6.24 |
| 2026-02-22 00:00 |
13:31:57.50 |
-61:31:17.9 |
HIP 65970 |
4.64 |
| 2026-02-22 12:00 |
13:31:49.51 |
-61:32:35.6 |
HIP 65970 |
3.03 |
| 2026-02-23 00:00 |
13:31:41.37 |
-61:33:52.4 |
HIP 65970 |
1.43 |
| 2026-02-23 12:00 |
13:31:33.08 |
-61:35:08.3 |
HIP 65970 |
0.20 |
| 2026-02-24 00:00 |
13:31:24.64 |
-61:36:23.3 |
HIP 65970 |
1.78 |