| 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 |
0.999 |
| 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) |
| 2026-07-29 00:00 |
15:51:29.28 |
-22:18:07.1 |
HIP 77642 |
20.25 |
| 2026-07-29 12:00 |
15:51:26.60 |
-22:17:44.2 |
HIP 77642 |
20.46 |
| 2026-07-30 00:00 |
15:51:24.01 |
-22:17:21.5 |
HIP 77642 |
20.69 |
| 2026-07-30 12:00 |
15:51:21.49 |
-22:16:59.0 |
HIP 77642 |
20.95 |
| 2026-07-31 00:00 |
15:51:19.05 |
-22:16:36.8 |
HIP 77642 |
21.22 |
| 2026-07-31 12:00 |
15:51:16.70 |
-22:16:14.8 |
HIP 77642 |
21.51 |
| 2026-08-01 00:00 |
15:51:14.42 |
-22:15:53.1 |
HIP 77642 |
21.81 |
| 2026-08-01 12:00 |
15:51:12.22 |
-22:15:31.6 |
HIP 77642 |
22.12 |
| 2026-08-02 00:00 |
15:51:10.10 |
-22:15:10.3 |
HIP 77642 |
22.45 |
| 2026-08-02 12:00 |
15:51:08.07 |
-22:14:49.3 |
HIP 77642 |
22.78 |
| 2026-08-03 00:00 |
15:51:06.11 |
-22:14:28.5 |
HIP 77642 |
23.12 |
| 2026-08-03 12:00 |
15:51:04.23 |
-22:14:08.0 |
HIP 77642 |
23.46 |
| 2026-08-04 00:00 |
15:51:02.43 |
-22:13:47.8 |
HIP 77642 |
23.81 |
| 2026-08-04 12:00 |
15:51:00.72 |
-22:13:27.7 |
HIP 77642 |
24.15 |
| 2026-08-05 00:00 |
15:50:59.08 |
-22:13:08.0 |
HIP 77642 |
24.50 |
| 2026-08-05 12:00 |
15:50:57.52 |
-22:12:48.4 |
HIP 77642 |
24.85 |
| 2026-08-06 00:00 |
15:50:56.05 |
-22:12:29.2 |
HIP 77642 |
25.20 |
| 2026-08-06 12:00 |
15:50:54.65 |
-22:12:10.1 |
HIP 77642 |
25.54 |
| 2026-08-07 00:00 |
15:50:53.34 |
-22:11:51.4 |
HIP 77642 |
25.88 |
| 2026-08-07 12:00 |
15:50:52.10 |
-22:11:32.8 |
HIP 77642 |
26.22 |
| 2026-08-08 00:00 |
15:50:50.95 |
-22:11:14.6 |
HIP 77642 |
26.56 |
| 2026-08-08 12:00 |
15:50:49.88 |
-22:10:56.6 |
HIP 77642 |
26.89 |
| 2026-08-09 00:00 |
15:50:48.89 |
-22:10:38.8 |
HIP 77642 |
27.21 |
| 2026-08-09 12:00 |
15:50:47.98 |
-22:10:21.3 |
HIP 77642 |
27.53 |
| 2026-08-10 00:00 |
15:50:47.15 |
-22:10:04.1 |
HIP 77642 |
27.84 |
| 2026-08-10 12:00 |
15:50:46.41 |
-22:09:47.1 |
HIP 77642 |
28.15 |
| 2026-08-11 00:00 |
15:50:45.74 |
-22:09:30.4 |
HIP 77642 |
28.45 |
| 2026-08-11 12:00 |
15:50:45.16 |
-22:09:13.9 |
HIP 77642 |
28.74 |
| 2026-08-12 00:00 |
15:50:44.66 |
-22:08:57.7 |
HIP 77642 |
29.02 |
| 2026-08-12 12:00 |
15:50:44.23 |
-22:08:41.7 |
HIP 77642 |
29.30 |
| 2026-08-13 00:00 |
15:50:43.89 |
-22:08:26.1 |
HIP 77642 |
29.57 |
| 2026-08-13 12:00 |
15:50:43.64 |
-22:08:10.6 |
HIP 77642 |
29.84 |
| 2026-08-14 00:00 |
15:50:43.46 |
-22:07:55.5 |
HIP 77642 |
30.09 |
| 2026-08-14 12:00 |
15:50:43.36 |
-22:07:40.5 |
HIP 77642 |
30.34 |
| 2026-08-15 00:00 |
15:50:43.35 |
-22:07:25.9 |
HIP 77642 |
30.58 |
| 2026-08-15 12:00 |
15:50:43.41 |
-22:07:11.5 |
HIP 77642 |
30.82 |
| 2026-08-16 00:00 |
15:50:43.56 |
-22:06:57.4 |
HIP 77642 |
31.04 |
| 2026-08-16 12:00 |
15:50:43.79 |
-22:06:43.5 |
HIP 77642 |
31.26 |
| 2026-08-17 00:00 |
15:50:44.09 |
-22:06:29.9 |
HIP 77642 |
31.48 |
| 2026-08-17 12:00 |
15:50:44.48 |
-22:06:16.5 |
HIP 77642 |
31.68 |
| 2026-08-18 00:00 |
15:50:44.95 |
-22:06:03.4 |
HIP 77642 |
31.88 |
| 2026-08-18 12:00 |
15:50:45.50 |
-22:05:50.6 |
HIP 77642 |
32.08 |
| 2026-08-19 00:00 |
15:50:46.13 |
-22:05:38.0 |
HIP 77642 |
32.26 |