| Parameter |
Value |
| Designation |
449P/Leonard |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-11-23T14:34:44.742720Z |
| Orbit solution date (soln_date, UTC) |
2024-02-25T22:13:10Z |
| Obs used |
294 |
| NEO |
- |
| M1 |
8.600 |
| K1 |
37.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
1987-03-23T09:59:28.320000Z |
| Discovery magnitude (MPC) |
17.50 T |
| Discovery observatory (MPC) |
260 · Siding Spring Observatory-DSS |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2020-10-20.0000000 |
| e |
0.47899106 |
| q (au) |
1.874781 |
| a (au) |
3.598367 |
| i (deg) |
15.459226 |
| Ω (om, deg) |
242.570978 |
| ω (w, deg) |
176.651702 |
| M (ma, deg) |
355.002928 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.886 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.886 |
| n |
6.000 |
| gf |
0.998 |
| gb |
-0.800 |
| k |
0.993 |
| 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 |
20:22:46.40 |
-05:56:28.9 |
HIP 100520 |
16.28 |
| 2026-05-12 12:00 |
20:22:51.92 |
-05:53:47.4 |
HIP 100520 |
13.39 |
| 2026-05-13 00:00 |
20:22:57.20 |
-05:51:06.2 |
HIP 100520 |
10.59 |
| 2026-05-13 12:00 |
20:23:02.24 |
-05:48:25.4 |
HIP 100520 |
7.92 |
| 2026-05-14 00:00 |
20:23:07.05 |
-05:45:44.9 |
HIP 100520 |
5.54 |
| 2026-05-14 12:00 |
20:23:11.62 |
-05:43:04.9 |
HIP 100520 |
3.94 |
| 2026-05-15 00:00 |
20:23:15.95 |
-05:40:25.3 |
HIP 100520 |
4.09 |
| 2026-05-15 12:00 |
20:23:20.04 |
-05:37:46.1 |
HIP 100520 |
5.81 |
| 2026-05-16 00:00 |
20:23:23.89 |
-05:35:07.4 |
HIP 100520 |
8.13 |
| 2026-05-16 12:00 |
20:23:27.50 |
-05:32:29.1 |
HIP 100520 |
10.64 |
| 2026-05-17 00:00 |
20:23:30.87 |
-05:29:51.3 |
HIP 100520 |
13.22 |
| 2026-05-17 12:00 |
20:23:33.99 |
-05:27:13.9 |
HIP 100570 |
11.31 |
| 2026-05-18 00:00 |
20:23:36.87 |
-05:24:37.1 |
HIP 100570 |
8.65 |
| 2026-05-18 12:00 |
20:23:39.50 |
-05:22:00.7 |
HIP 100570 |
6.05 |
| 2026-05-19 00:00 |
20:23:41.89 |
-05:19:24.9 |
HIP 100570 |
3.56 |
| 2026-05-19 12:00 |
20:23:44.03 |
-05:16:49.6 |
HIP 100570 |
1.68 |
| 2026-05-20 00:00 |
20:23:45.92 |
-05:14:14.8 |
HIP 100570 |
2.58 |
| 2026-05-20 12:00 |
20:23:47.56 |
-05:11:40.6 |
HIP 100570 |
4.88 |
| 2026-05-21 00:00 |
20:23:48.96 |
-05:09:06.9 |
HIP 100570 |
7.36 |
| 2026-05-21 12:00 |
20:23:50.11 |
-05:06:33.8 |
HIP 100570 |
9.86 |
| 2026-05-22 00:00 |
20:23:51.01 |
-05:04:01.2 |
HIP 100570 |
12.37 |
| 2026-05-22 12:00 |
20:23:51.65 |
-05:01:29.3 |
HIP 100570 |
14.86 |
| 2026-05-23 00:00 |
20:23:52.05 |
-04:58:58.0 |
HIP 100570 |
17.35 |
| 2026-05-23 12:00 |
20:23:52.20 |
-04:56:27.2 |
HIP 100570 |
19.82 |
| 2026-05-24 00:00 |
20:23:52.09 |
-04:53:57.1 |
HIP 100489 |
20.99 |
| 2026-05-24 12:00 |
20:23:51.73 |
-04:51:27.7 |
HIP 100669 |
20.50 |
| 2026-05-25 00:00 |
20:23:51.12 |
-04:48:58.9 |
HIP 100669 |
18.67 |
| 2026-05-25 12:00 |
20:23:50.25 |
-04:46:30.7 |
HIP 100669 |
17.07 |
| 2026-05-26 00:00 |
20:23:49.13 |
-04:44:03.2 |
HIP 100669 |
15.76 |
| 2026-05-26 12:00 |
20:23:47.76 |
-04:41:36.4 |
HIP 100669 |
14.81 |
| 2026-05-27 00:00 |
20:23:46.13 |
-04:39:10.3 |
HIP 100669 |
14.29 |
| 2026-05-27 12:00 |
20:23:44.24 |
-04:36:44.9 |
HIP 100669 |
14.26 |
| 2026-05-28 00:00 |
20:23:42.10 |
-04:34:20.2 |
HIP 100669 |
14.71 |
| 2026-05-28 12:00 |
20:23:39.70 |
-04:31:56.2 |
HIP 100669 |
15.60 |
| 2026-05-29 00:00 |
20:23:37.05 |
-04:29:33.0 |
HIP 100669 |
16.88 |
| 2026-05-29 12:00 |
20:23:34.13 |
-04:27:10.5 |
HIP 100669 |
18.45 |
| 2026-05-30 00:00 |
20:23:30.96 |
-04:24:48.8 |
HIP 100669 |
20.25 |
| 2026-05-30 12:00 |
20:23:27.53 |
-04:22:27.9 |
HIP 100669 |
22.23 |
| 2026-05-31 00:00 |
20:23:23.84 |
-04:20:07.7 |
HIP 100669 |
24.36 |
| 2026-05-31 12:00 |
20:23:19.89 |
-04:17:48.4 |
HIP 100669 |
26.59 |
| 2026-06-01 00:00 |
20:23:15.68 |
-04:15:29.9 |
HIP 100535 |
26.85 |
| 2026-06-01 12:00 |
20:23:11.21 |
-04:13:12.2 |
HIP 100535 |
24.50 |
| 2026-06-02 00:00 |
20:23:06.48 |
-04:10:55.4 |
HIP 100535 |
22.22 |