| Parameter |
Value |
| Designation |
C/2019 T5 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-08-01T03:25:59.563200Z |
| Orbit solution date (soln_date, UTC) |
2021-05-02T23:42:54Z |
| Obs used |
80 |
| NEO |
- |
| M1 |
14.900 |
| K1 |
9.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-10-08T14:44:47.270400Z |
| Discovery magnitude (MPC) |
18.99 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-11-03.0000000 |
| e |
0.80920592 |
| q (au) |
1.528889 |
| a (au) |
8.013295 |
| i (deg) |
33.422394 |
| Ω (om, deg) |
247.696368 |
| ω (w, deg) |
189.617261 |
| M (ma, deg) |
4.078062 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.884 + 4.415\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.884 |
| n |
4.415 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.996 |
| 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) |
| 2026-05-12 00:00 |
16:10:15.16 |
-23:43:55.2 |
HIP 79098 |
21.12 |
| 2026-05-12 12:00 |
16:10:06.17 |
-23:43:23.0 |
HIP 79098 |
19.01 |
| 2026-05-13 00:00 |
16:09:57.15 |
-23:42:50.6 |
HIP 79098 |
16.90 |
| 2026-05-13 12:00 |
16:09:48.11 |
-23:42:18.1 |
HIP 79098 |
14.79 |
| 2026-05-14 00:00 |
16:09:39.05 |
-23:41:45.4 |
HIP 79098 |
12.68 |
| 2026-05-14 12:00 |
16:09:29.97 |
-23:41:12.6 |
HIP 79098 |
10.59 |
| 2026-05-15 00:00 |
16:09:20.88 |
-23:40:39.7 |
HIP 79098 |
8.52 |
| 2026-05-15 12:00 |
16:09:11.77 |
-23:40:06.6 |
HIP 79098 |
6.50 |
| 2026-05-16 00:00 |
16:09:02.64 |
-23:39:33.4 |
HIP 79098 |
4.60 |
| 2026-05-16 12:00 |
16:08:53.50 |
-23:39:00.0 |
HIP 79098 |
3.08 |
| 2026-05-17 00:00 |
16:08:44.35 |
-23:38:26.6 |
HIP 79098 |
2.68 |
| 2026-05-17 12:00 |
16:08:35.18 |
-23:37:53.0 |
HIP 79098 |
3.78 |
| 2026-05-18 00:00 |
16:08:26.00 |
-23:37:19.2 |
HIP 79098 |
5.56 |
| 2026-05-18 12:00 |
16:08:16.81 |
-23:36:45.4 |
HIP 79098 |
7.55 |
| 2026-05-19 00:00 |
16:08:07.61 |
-23:36:11.4 |
HIP 79098 |
9.63 |
| 2026-05-19 12:00 |
16:07:58.40 |
-23:35:37.3 |
HIP 79098 |
11.75 |
| 2026-05-20 00:00 |
16:07:49.19 |
-23:35:03.1 |
HIP 79098 |
13.89 |
| 2026-05-20 12:00 |
16:07:39.97 |
-23:34:28.8 |
HIP 79098 |
16.04 |
| 2026-05-21 00:00 |
16:07:30.74 |
-23:33:54.3 |
HIP 79098 |
18.21 |
| 2026-05-21 12:00 |
16:07:21.51 |
-23:33:19.8 |
HIP 78877 |
17.48 |
| 2026-05-22 00:00 |
16:07:12.28 |
-23:32:45.2 |
HIP 78877 |
15.53 |
| 2026-05-22 12:00 |
16:07:03.04 |
-23:32:10.4 |
HIP 78877 |
13.64 |
| 2026-05-23 00:00 |
16:06:53.80 |
-23:31:35.6 |
HIP 78877 |
11.87 |
| 2026-05-23 12:00 |
16:06:44.56 |
-23:31:00.6 |
HIP 78877 |
10.26 |
| 2026-05-24 00:00 |
16:06:35.32 |
-23:30:25.6 |
HIP 78877 |
8.91 |
| 2026-05-24 12:00 |
16:06:26.08 |
-23:29:50.5 |
HIP 78877 |
7.94 |
| 2026-05-25 00:00 |
16:06:16.85 |
-23:29:15.3 |
HIP 78877 |
7.51 |
| 2026-05-25 12:00 |
16:06:07.61 |
-23:28:40.0 |
HIP 78877 |
7.71 |
| 2026-05-26 00:00 |
16:05:58.38 |
-23:28:04.6 |
HIP 78877 |
8.50 |
| 2026-05-26 12:00 |
16:05:49.16 |
-23:27:29.2 |
HIP 78877 |
9.73 |
| 2026-05-27 00:00 |
16:05:39.94 |
-23:26:53.6 |
HIP 78877 |
11.25 |
| 2026-05-27 12:00 |
16:05:30.72 |
-23:26:18.0 |
HIP 78877 |
12.97 |
| 2026-05-28 00:00 |
16:05:21.52 |
-23:25:42.3 |
HIP 78809 |
14.45 |
| 2026-05-28 12:00 |
16:05:12.32 |
-23:25:06.6 |
HIP 78809 |
15.12 |
| 2026-05-29 00:00 |
16:05:03.13 |
-23:24:30.8 |
HIP 78809 |
16.06 |
| 2026-05-29 12:00 |
16:04:53.96 |
-23:23:54.9 |
HIP 78809 |
17.23 |
| 2026-05-30 00:00 |
16:04:44.79 |
-23:23:18.9 |
HIP 78809 |
18.58 |
| 2026-05-30 12:00 |
16:04:35.63 |
-23:22:42.9 |
HIP 78809 |
20.08 |
| 2026-05-31 00:00 |
16:04:26.49 |
-23:22:06.9 |
HIP 78809 |
21.70 |
| 2026-05-31 12:00 |
16:04:17.36 |
-23:21:30.7 |
HIP 78809 |
23.40 |
| 2026-06-01 00:00 |
16:04:08.25 |
-23:20:54.6 |
HIP 78586 |
21.50 |
| 2026-06-01 12:00 |
16:03:59.15 |
-23:20:18.4 |
HIP 78586 |
19.38 |
| 2026-06-02 00:00 |
16:03:50.06 |
-23:19:42.1 |
HIP 78586 |
17.27 |