| Parameter |
Value |
| Designation |
C/2019 J3 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-08-01T21:21:25.338240Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:54Z |
| Obs used |
270 |
| NEO |
- |
| M1 |
15.300 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-05-14T13:01:15.024000Z |
| Discovery magnitude (MPC) |
18.73 o |
| Discovery observatory (MPC) |
T05 · ATLAS-HKO, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-07-10.0000000 |
| e |
1.00067795 |
| q (au) |
2.373522 |
| a (au) |
-3501.039615 |
| i (deg) |
131.414908 |
| Ω (om, deg) |
270.517035 |
| ω (w, deg) |
16.552399 |
| M (ma, deg) |
-0.000109 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.286 + 2.429\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.286 |
| n |
2.429 |
| gf |
0.944 |
| gb |
-0.898 |
| k |
0.999 |
| δ90 |
1.000 |
| 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 |
07:35:11.71 |
+39:46:29.3 |
HIP 37075 |
22.07 |
| 2026-07-29 12:00 |
07:35:18.40 |
+39:46:17.0 |
HIP 37075 |
20.79 |
| 2026-07-30 00:00 |
07:35:25.06 |
+39:46:05.0 |
HIP 37075 |
19.51 |
| 2026-07-30 12:00 |
07:35:31.71 |
+39:45:53.3 |
HIP 37075 |
18.23 |
| 2026-07-31 00:00 |
07:35:38.35 |
+39:45:41.7 |
HIP 37075 |
16.97 |
| 2026-07-31 12:00 |
07:35:44.96 |
+39:45:30.4 |
HIP 37075 |
15.71 |
| 2026-08-01 00:00 |
07:35:51.56 |
+39:45:19.4 |
HIP 37075 |
14.45 |
| 2026-08-01 12:00 |
07:35:58.14 |
+39:45:08.6 |
HIP 37075 |
13.21 |
| 2026-08-02 00:00 |
07:36:04.70 |
+39:44:58.0 |
HIP 37075 |
11.97 |
| 2026-08-02 12:00 |
07:36:11.24 |
+39:44:47.6 |
HIP 37075 |
10.75 |
| 2026-08-03 00:00 |
07:36:17.76 |
+39:44:37.5 |
HIP 37075 |
9.54 |
| 2026-08-03 12:00 |
07:36:24.26 |
+39:44:27.6 |
HIP 37075 |
8.35 |
| 2026-08-04 00:00 |
07:36:30.74 |
+39:44:18.0 |
HIP 37075 |
7.19 |
| 2026-08-04 12:00 |
07:36:37.20 |
+39:44:08.6 |
HIP 37075 |
6.06 |
| 2026-08-05 00:00 |
07:36:43.64 |
+39:43:59.5 |
HIP 37075 |
5.00 |
| 2026-08-05 12:00 |
07:36:50.05 |
+39:43:50.6 |
HIP 37075 |
4.05 |
| 2026-08-06 00:00 |
07:36:56.45 |
+39:43:41.9 |
HIP 37075 |
3.30 |
| 2026-08-06 12:00 |
07:37:02.82 |
+39:43:33.4 |
HIP 37075 |
2.89 |
| 2026-08-07 00:00 |
07:37:09.17 |
+39:43:25.3 |
HIP 37075 |
2.98 |
| 2026-08-07 12:00 |
07:37:15.49 |
+39:43:17.3 |
HIP 37075 |
3.51 |
| 2026-08-08 00:00 |
07:37:21.79 |
+39:43:09.6 |
HIP 37075 |
4.33 |
| 2026-08-08 12:00 |
07:37:28.06 |
+39:43:02.1 |
HIP 37075 |
5.30 |
| 2026-08-09 00:00 |
07:37:34.31 |
+39:42:54.9 |
HIP 37075 |
6.35 |
| 2026-08-09 12:00 |
07:37:40.54 |
+39:42:48.0 |
HIP 37075 |
7.43 |
| 2026-08-10 00:00 |
07:37:46.74 |
+39:42:41.2 |
HIP 37075 |
8.55 |
| 2026-08-10 12:00 |
07:37:52.91 |
+39:42:34.8 |
HIP 37075 |
9.67 |
| 2026-08-11 00:00 |
07:37:59.05 |
+39:42:28.5 |
HIP 37075 |
10.81 |
| 2026-08-11 12:00 |
07:38:05.17 |
+39:42:22.6 |
HIP 37075 |
11.95 |
| 2026-08-12 00:00 |
07:38:11.26 |
+39:42:16.8 |
HIP 37075 |
13.09 |
| 2026-08-12 12:00 |
07:38:17.32 |
+39:42:11.3 |
HIP 37075 |
14.22 |
| 2026-08-13 00:00 |
07:38:23.35 |
+39:42:06.1 |
HIP 37075 |
15.36 |
| 2026-08-13 12:00 |
07:38:29.35 |
+39:42:01.1 |
HIP 37075 |
16.49 |
| 2026-08-14 00:00 |
07:38:35.33 |
+39:41:56.4 |
HIP 37075 |
17.62 |
| 2026-08-14 12:00 |
07:38:41.27 |
+39:41:51.9 |
HIP 37075 |
18.75 |
| 2026-08-15 00:00 |
07:38:47.18 |
+39:41:47.7 |
HIP 37374 |
18.95 |
| 2026-08-15 12:00 |
07:38:53.06 |
+39:41:43.7 |
HIP 37374 |
17.90 |
| 2026-08-16 00:00 |
07:38:58.91 |
+39:41:39.9 |
HIP 37374 |
16.88 |
| 2026-08-16 12:00 |
07:39:04.73 |
+39:41:36.5 |
HIP 37374 |
15.87 |
| 2026-08-17 00:00 |
07:39:10.51 |
+39:41:33.2 |
HIP 37374 |
14.88 |
| 2026-08-17 12:00 |
07:39:16.26 |
+39:41:30.2 |
HIP 37374 |
13.91 |
| 2026-08-18 00:00 |
07:39:21.98 |
+39:41:27.5 |
HIP 37374 |
12.97 |
| 2026-08-18 12:00 |
07:39:27.66 |
+39:41:25.0 |
HIP 37374 |
12.06 |
| 2026-08-19 00:00 |
07:39:33.31 |
+39:41:22.8 |
HIP 37374 |
11.18 |