| Parameter |
Value |
| Designation |
372P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2009-04-21T12:58:57.285120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:37Z |
| Obs used |
438 |
| NEO |
- |
| M1 |
7.100 |
| K1 |
15.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2018-08-08T11:54:29.952000Z |
| Discovery magnitude (MPC) |
22.40 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-04-15.0000000 |
| e |
0.15350456 |
| q (au) |
3.803759 |
| a (au) |
4.493537 |
| i (deg) |
9.518532 |
| Ω (om, deg) |
325.860084 |
| ω (w, deg) |
27.455141 |
| M (ma, deg) |
359.323198 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.453 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.453 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.504 |
| k |
1.000 |
| 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 |
17:50:27.63 |
-34:07:16.0 |
HIP 87230 |
13.29 |
| 2026-05-12 12:00 |
17:50:15.35 |
-34:07:48.0 |
HIP 87230 |
10.86 |
| 2026-05-13 00:00 |
17:50:02.83 |
-34:08:19.4 |
HIP 87230 |
8.48 |
| 2026-05-13 12:00 |
17:49:50.08 |
-34:08:50.1 |
HIP 87230 |
6.27 |
| 2026-05-14 00:00 |
17:49:37.10 |
-34:09:20.2 |
HIP 87230 |
4.57 |
| 2026-05-14 12:00 |
17:49:23.89 |
-34:09:49.6 |
HIP 87230 |
4.15 |
| 2026-05-15 00:00 |
17:49:10.45 |
-34:10:18.3 |
HIP 87230 |
5.40 |
| 2026-05-15 12:00 |
17:48:56.79 |
-34:10:46.3 |
HIP 87230 |
7.58 |
| 2026-05-16 00:00 |
17:48:42.90 |
-34:11:13.6 |
HIP 87230 |
10.14 |
| 2026-05-16 12:00 |
17:48:28.79 |
-34:11:40.2 |
HIP 87102 |
11.01 |
| 2026-05-17 00:00 |
17:48:14.47 |
-34:12:06.0 |
HIP 87102 |
8.59 |
| 2026-05-17 12:00 |
17:47:59.93 |
-34:12:31.1 |
HIP 87102 |
6.64 |
| 2026-05-18 00:00 |
17:47:45.18 |
-34:12:55.4 |
HIP 87102 |
5.74 |
| 2026-05-18 12:00 |
17:47:30.22 |
-34:13:19.0 |
HIP 87102 |
6.42 |
| 2026-05-19 00:00 |
17:47:15.05 |
-34:13:41.8 |
HIP 87102 |
8.34 |
| 2026-05-19 12:00 |
17:46:59.68 |
-34:14:03.8 |
HIP 87102 |
10.90 |
| 2026-05-20 00:00 |
17:46:44.10 |
-34:14:25.0 |
HIP 87102 |
13.77 |
| 2026-05-20 12:00 |
17:46:28.33 |
-34:14:45.4 |
HIP 87102 |
16.82 |
| 2026-05-21 00:00 |
17:46:12.36 |
-34:15:04.9 |
HIP 87102 |
19.98 |
| 2026-05-21 12:00 |
17:45:56.20 |
-34:15:23.7 |
HIP 86947 |
19.77 |
| 2026-05-22 00:00 |
17:45:39.85 |
-34:15:41.6 |
HIP 86947 |
19.93 |
| 2026-05-22 12:00 |
17:45:23.32 |
-34:15:58.6 |
HIP 86947 |
20.67 |
| 2026-05-23 00:00 |
17:45:06.60 |
-34:16:14.8 |
HIP 86752 |
21.90 |
| 2026-05-23 12:00 |
17:44:49.70 |
-34:16:30.1 |
HIP 86752 |
19.15 |
| 2026-05-24 00:00 |
17:44:32.63 |
-34:16:44.6 |
HIP 86752 |
16.65 |
| 2026-05-24 12:00 |
17:44:15.38 |
-34:16:58.1 |
HIP 86752 |
14.56 |
| 2026-05-25 00:00 |
17:43:57.96 |
-34:17:10.7 |
HIP 86752 |
13.10 |
| 2026-05-25 12:00 |
17:43:40.37 |
-34:17:22.5 |
HIP 86752 |
12.52 |
| 2026-05-26 00:00 |
17:43:22.62 |
-34:17:33.3 |
HIP 86752 |
12.97 |
| 2026-05-26 12:00 |
17:43:04.71 |
-34:17:43.2 |
HIP 86752 |
14.38 |
| 2026-05-27 00:00 |
17:42:46.64 |
-34:17:52.2 |
HIP 86752 |
16.53 |
| 2026-05-27 12:00 |
17:42:28.42 |
-34:18:00.2 |
HIP 86572 |
18.09 |
| 2026-05-28 00:00 |
17:42:10.05 |
-34:18:07.3 |
HIP 86572 |
15.95 |
| 2026-05-28 12:00 |
17:41:51.52 |
-34:18:13.4 |
HIP 86572 |
14.47 |
| 2026-05-29 00:00 |
17:41:32.86 |
-34:18:18.6 |
HIP 86572 |
13.91 |
| 2026-05-29 12:00 |
17:41:14.05 |
-34:18:22.8 |
HIP 86572 |
14.39 |
| 2026-05-30 00:00 |
17:40:55.11 |
-34:18:26.0 |
HIP 86572 |
15.84 |
| 2026-05-30 12:00 |
17:40:36.03 |
-34:18:28.2 |
HIP 86572 |
18.04 |
| 2026-05-31 00:00 |
17:40:16.83 |
-34:18:29.5 |
HIP 86572 |
20.78 |
| 2026-05-31 12:00 |
17:39:57.49 |
-34:18:29.7 |
HIP 86572 |
23.87 |
| 2026-06-01 00:00 |
17:39:38.04 |
-34:18:29.0 |
HIP 86572 |
27.22 |
| 2026-06-01 12:00 |
17:39:18.46 |
-34:18:27.2 |
HIP 86256 |
29.86 |
| 2026-06-02 00:00 |
17:38:58.77 |
-34:18:24.4 |
HIP 86256 |
27.06 |