P/2019 A6 (Lemmon-PANSTARRS)
| Parameter |
Value |
| Designation |
P/2019 A6 (Lemmon-PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-08-29T07:25:19.718400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:50Z |
| Obs used |
55 |
| NEO |
- |
| M1 |
17.900 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-01-07T12:20:51.936000Z |
| Discovery magnitude (MPC) |
20.70 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-01-05.0000000 |
| e |
0.63917742 |
| q (au) |
1.938506 |
| a (au) |
5.372463 |
| i (deg) |
33.228328 |
| Ω (om, deg) |
280.271890 |
| ω (w, deg) |
156.305004 |
| M (ma, deg) |
10.185707 |
Magnitude
Scatter + Global Linear
$$
M_a = (18.765 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
18.765 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.558 |
| k |
0.800 |
| 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) |
| 2026-02-03 00:00 |
18:14:51.29 |
-30:08:04.3 |
HIP 89429 |
18.93 |
| 2026-02-03 12:00 |
18:15:05.34 |
-30:07:52.3 |
HIP 89429 |
18.49 |
| 2026-02-04 00:00 |
18:15:19.32 |
-30:07:40.5 |
HIP 89429 |
18.55 |
| 2026-02-04 12:00 |
18:15:33.23 |
-30:07:28.7 |
HIP 89429 |
19.10 |
| 2026-02-05 00:00 |
18:15:47.07 |
-30:07:17.0 |
HIP 89429 |
20.08 |
| 2026-02-05 12:00 |
18:16:00.84 |
-30:07:05.3 |
HIP 89628 |
20.24 |
| 2026-02-06 00:00 |
18:16:14.55 |
-30:06:53.7 |
HIP 89628 |
17.42 |
| 2026-02-06 12:00 |
18:16:28.18 |
-30:06:42.2 |
HIP 89628 |
14.66 |
| 2026-02-07 00:00 |
18:16:41.74 |
-30:06:30.8 |
HIP 89628 |
12.01 |
| 2026-02-07 12:00 |
18:16:55.23 |
-30:06:19.5 |
HIP 89628 |
9.55 |
| 2026-02-08 00:00 |
18:17:08.64 |
-30:06:08.2 |
HIP 89628 |
7.45 |
| 2026-02-08 12:00 |
18:17:21.98 |
-30:05:57.0 |
HIP 89628 |
6.05 |
| 2026-02-09 00:00 |
18:17:35.25 |
-30:05:45.8 |
HIP 89628 |
5.88 |
| 2026-02-09 12:00 |
18:17:48.44 |
-30:05:34.8 |
HIP 89628 |
6.99 |
| 2026-02-10 00:00 |
18:18:01.55 |
-30:05:23.8 |
HIP 89716 |
7.33 |
| 2026-02-10 12:00 |
18:18:14.59 |
-30:05:12.9 |
HIP 89716 |
4.62 |
| 2026-02-11 00:00 |
18:18:27.55 |
-30:05:02.1 |
HIP 89716 |
2.25 |
| 2026-02-11 12:00 |
18:18:40.43 |
-30:04:51.4 |
HIP 89716 |
2.13 |
| 2026-02-12 00:00 |
18:18:53.23 |
-30:04:40.7 |
HIP 89716 |
4.41 |
| 2026-02-12 12:00 |
18:19:05.95 |
-30:04:30.1 |
HIP 89716 |
7.04 |
| 2026-02-13 00:00 |
18:19:18.59 |
-30:04:19.7 |
HIP 89716 |
9.72 |
| 2026-02-13 12:00 |
18:19:31.15 |
-30:04:09.2 |
HIP 89716 |
12.41 |
| 2026-02-14 00:00 |
18:19:43.62 |
-30:03:58.9 |
HIP 89904 |
13.18 |
| 2026-02-14 12:00 |
18:19:56.02 |
-30:03:48.7 |
HIP 89904 |
10.67 |
| 2026-02-15 00:00 |
18:20:08.33 |
-30:03:38.5 |
HIP 89904 |
8.28 |
| 2026-02-15 12:00 |
18:20:20.55 |
-30:03:28.4 |
HIP 89904 |
6.13 |
| 2026-02-16 00:00 |
18:20:32.69 |
-30:03:18.5 |
HIP 89904 |
4.56 |
| 2026-02-16 12:00 |
18:20:44.74 |
-30:03:08.5 |
HIP 89904 |
4.22 |
| 2026-02-17 00:00 |
18:20:56.70 |
-30:02:58.7 |
HIP 89904 |
5.33 |
| 2026-02-17 12:00 |
18:21:08.58 |
-30:02:49.0 |
HIP 89904 |
7.22 |
| 2026-02-18 00:00 |
18:21:20.37 |
-30:02:39.4 |
HIP 89904 |
9.42 |
| 2026-02-18 12:00 |
18:21:32.07 |
-30:02:29.8 |
HIP 89904 |
11.75 |
| 2026-02-19 00:00 |
18:21:43.68 |
-30:02:20.4 |
HIP 90011 |
12.64 |
| 2026-02-19 12:00 |
18:21:55.19 |
-30:02:11.0 |
HIP 90011 |
12.34 |
| 2026-02-20 00:00 |
18:22:06.62 |
-30:02:01.7 |
HIP 90011 |
12.53 |
| 2026-02-20 12:00 |
18:22:17.95 |
-30:01:52.5 |
HIP 90011 |
13.18 |
| 2026-02-21 00:00 |
18:22:29.19 |
-30:01:43.4 |
HIP 90011 |
14.23 |
| 2026-02-21 12:00 |
18:22:40.34 |
-30:01:34.4 |
HIP 90011 |
15.57 |
| 2026-02-22 00:00 |
18:22:51.39 |
-30:01:25.5 |
HIP 90011 |
17.14 |
| 2026-02-22 12:00 |
18:23:02.35 |
-30:01:16.7 |
HIP 90011 |
18.86 |
| 2026-02-23 00:00 |
18:23:13.21 |
-30:01:08.0 |
HIP 90158 |
20.11 |
| 2026-02-23 12:00 |
18:23:23.98 |
-30:00:59.3 |
HIP 90158 |
19.30 |
| 2026-02-24 00:00 |
18:23:34.64 |
-30:00:50.8 |
HIP 90158 |
18.74 |