C/2019 Q1 (Lemmon)
| Parameter |
Value |
| Designation |
C/2019 Q1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-07-19T15:31:26.172480Z |
| Orbit solution date (soln_date, UTC) |
2024-03-12T13:12:25Z |
| Obs used |
248 |
| NEO |
- |
| M1 |
13.900 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-08-28T09:37:41.952000Z |
| Discovery magnitude (MPC) |
20.60 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-04-08.0000000 |
| e |
1.00092868 |
| q (au) |
4.997085 |
| a (au) |
-5380.822928 |
| i (deg) |
155.721870 |
| Ω (om, deg) |
42.338664 |
| ω (w, deg) |
55.917769 |
| M (ma, deg) |
-0.000256 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.131 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.131 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.790 |
| 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 |
16:02:20.24 |
-13:59:43.3 |
HIP 78600 |
13.39 |
| 2026-02-03 12:00 |
16:02:20.99 |
-13:59:42.5 |
HIP 78600 |
13.28 |
| 2026-02-04 00:00 |
16:02:21.67 |
-13:59:41.4 |
HIP 78600 |
13.17 |
| 2026-02-04 12:00 |
16:02:22.28 |
-13:59:40.0 |
HIP 78600 |
13.07 |
| 2026-02-05 00:00 |
16:02:22.82 |
-13:59:38.4 |
HIP 78600 |
12.97 |
| 2026-02-05 12:00 |
16:02:23.29 |
-13:59:36.6 |
HIP 78600 |
12.89 |
| 2026-02-06 00:00 |
16:02:23.70 |
-13:59:34.6 |
HIP 78600 |
12.81 |
| 2026-02-06 12:00 |
16:02:24.03 |
-13:59:32.3 |
HIP 78600 |
12.73 |
| 2026-02-07 00:00 |
16:02:24.30 |
-13:59:29.7 |
HIP 78600 |
12.66 |
| 2026-02-07 12:00 |
16:02:24.49 |
-13:59:27.0 |
HIP 78600 |
12.60 |
| 2026-02-08 00:00 |
16:02:24.62 |
-13:59:23.9 |
HIP 78600 |
12.54 |
| 2026-02-08 12:00 |
16:02:24.67 |
-13:59:20.7 |
HIP 78600 |
12.49 |
| 2026-02-09 00:00 |
16:02:24.65 |
-13:59:17.2 |
HIP 78600 |
12.44 |
| 2026-02-09 12:00 |
16:02:24.57 |
-13:59:13.5 |
HIP 78600 |
12.40 |
| 2026-02-10 00:00 |
16:02:24.41 |
-13:59:09.5 |
HIP 78600 |
12.36 |
| 2026-02-10 12:00 |
16:02:24.18 |
-13:59:05.4 |
HIP 78600 |
12.33 |
| 2026-02-11 00:00 |
16:02:23.87 |
-13:59:00.9 |
HIP 78600 |
12.31 |
| 2026-02-11 12:00 |
16:02:23.50 |
-13:58:56.3 |
HIP 78600 |
12.30 |
| 2026-02-12 00:00 |
16:02:23.05 |
-13:58:51.4 |
HIP 78600 |
12.29 |
| 2026-02-12 12:00 |
16:02:22.53 |
-13:58:46.2 |
HIP 78600 |
12.29 |
| 2026-02-13 00:00 |
16:02:21.94 |
-13:58:40.9 |
HIP 78600 |
12.30 |
| 2026-02-13 12:00 |
16:02:21.27 |
-13:58:35.3 |
HIP 78600 |
12.32 |
| 2026-02-14 00:00 |
16:02:20.53 |
-13:58:29.4 |
HIP 78600 |
12.36 |
| 2026-02-14 12:00 |
16:02:19.72 |
-13:58:23.4 |
HIP 78600 |
12.40 |
| 2026-02-15 00:00 |
16:02:18.83 |
-13:58:17.1 |
HIP 78600 |
12.45 |
| 2026-02-15 12:00 |
16:02:17.87 |
-13:58:10.5 |
HIP 78600 |
12.52 |
| 2026-02-16 00:00 |
16:02:16.84 |
-13:58:03.8 |
HIP 78600 |
12.60 |
| 2026-02-16 12:00 |
16:02:15.73 |
-13:57:56.8 |
HIP 78600 |
12.70 |
| 2026-02-17 00:00 |
16:02:14.55 |
-13:57:49.6 |
HIP 78600 |
12.81 |
| 2026-02-17 12:00 |
16:02:13.29 |
-13:57:42.1 |
HIP 78600 |
12.94 |
| 2026-02-18 00:00 |
16:02:11.96 |
-13:57:34.4 |
HIP 78600 |
13.09 |
| 2026-02-18 12:00 |
16:02:10.56 |
-13:57:26.5 |
HIP 78600 |
13.26 |
| 2026-02-19 00:00 |
16:02:09.08 |
-13:57:18.4 |
HIP 78600 |
13.44 |
| 2026-02-19 12:00 |
16:02:07.52 |
-13:57:10.1 |
HIP 78600 |
13.65 |
| 2026-02-20 00:00 |
16:02:05.89 |
-13:57:01.5 |
HIP 78600 |
13.88 |
| 2026-02-20 12:00 |
16:02:04.18 |
-13:56:52.7 |
HIP 78600 |
14.12 |
| 2026-02-21 00:00 |
16:02:02.40 |
-13:56:43.6 |
HIP 78600 |
14.40 |
| 2026-02-21 12:00 |
16:02:00.55 |
-13:56:34.4 |
HIP 78600 |
14.69 |
| 2026-02-22 00:00 |
16:01:58.62 |
-13:56:24.9 |
HIP 78600 |
15.01 |
| 2026-02-22 12:00 |
16:01:56.61 |
-13:56:15.2 |
HIP 78600 |
15.35 |
| 2026-02-23 00:00 |
16:01:54.53 |
-13:56:05.3 |
HIP 78600 |
15.71 |
| 2026-02-23 12:00 |
16:01:52.37 |
-13:55:55.2 |
HIP 78600 |
16.10 |
| 2026-02-24 00:00 |
16:01:50.14 |
-13:55:44.9 |
HIP 78600 |
16.51 |