45P/Honda-Mrkos-Pajdusakova
| Parameter |
Value |
| Designation |
45P/Honda-Mrkos-Pajdusakova |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-12-31T06:49:10.395840Z |
| Orbit solution date (soln_date, UTC) |
2022-07-19T02:06:34Z |
| Obs used |
1823 |
| NEO |
Yes |
| M1 |
13.700 |
| K1 |
22.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-08-14.0000000 |
| e |
0.82399608 |
| q (au) |
0.532650 |
| a (au) |
3.026354 |
| i (deg) |
4.248171 |
| Ω (om, deg) |
88.934602 |
| ω (w, deg) |
326.344198 |
| M (ma, deg) |
42.255824 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.983 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.983 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-02-03 00:00 |
17:13:20.23 |
-21:47:32.4 |
HIP 84198 |
14.64 |
| 2026-02-03 12:00 |
17:13:39.65 |
-21:47:53.7 |
HIP 84198 |
18.12 |
| 2026-02-04 00:00 |
17:13:58.98 |
-21:48:14.7 |
HIP 84198 |
21.95 |
| 2026-02-04 12:00 |
17:14:18.19 |
-21:48:35.4 |
HIP 84198 |
25.98 |
| 2026-02-05 00:00 |
17:14:37.30 |
-21:48:55.9 |
HIP 84491 |
24.88 |
| 2026-02-05 12:00 |
17:14:56.29 |
-21:49:16.0 |
HIP 84491 |
20.46 |
| 2026-02-06 00:00 |
17:15:15.18 |
-21:49:35.8 |
HIP 84491 |
16.06 |
| 2026-02-06 12:00 |
17:15:33.96 |
-21:49:55.4 |
HIP 84491 |
11.70 |
| 2026-02-07 00:00 |
17:15:52.62 |
-21:50:14.6 |
HIP 84491 |
7.37 |
| 2026-02-07 12:00 |
17:16:11.17 |
-21:50:33.6 |
HIP 84491 |
3.09 |
| 2026-02-08 00:00 |
17:16:29.60 |
-21:50:52.3 |
HIP 84491 |
1.44 |
| 2026-02-08 12:00 |
17:16:47.92 |
-21:51:10.7 |
HIP 84491 |
5.57 |
| 2026-02-09 00:00 |
17:17:06.12 |
-21:51:28.8 |
HIP 84491 |
9.79 |
| 2026-02-09 12:00 |
17:17:24.20 |
-21:51:46.6 |
HIP 84491 |
13.99 |
| 2026-02-10 00:00 |
17:17:42.16 |
-21:52:04.2 |
HIP 84491 |
18.16 |
| 2026-02-10 12:00 |
17:18:00.00 |
-21:52:21.4 |
HIP 84491 |
22.31 |
| 2026-02-11 00:00 |
17:18:17.72 |
-21:52:38.4 |
HIP 84491 |
26.43 |
| 2026-02-11 12:00 |
17:18:35.31 |
-21:52:55.1 |
HIP 84798 |
28.58 |
| 2026-02-12 00:00 |
17:18:52.78 |
-21:53:11.6 |
HIP 84798 |
26.24 |
| 2026-02-12 12:00 |
17:19:10.12 |
-21:53:27.7 |
HIP 84798 |
24.36 |
| 2026-02-13 00:00 |
17:19:27.34 |
-21:53:43.6 |
HIP 84798 |
23.05 |
| 2026-02-13 12:00 |
17:19:44.42 |
-21:53:59.2 |
HIP 84798 |
22.38 |
| 2026-02-14 00:00 |
17:20:01.37 |
-21:54:14.5 |
HIP 84798 |
22.41 |
| 2026-02-14 12:00 |
17:20:18.20 |
-21:54:29.6 |
HIP 84869 |
20.75 |
| 2026-02-15 00:00 |
17:20:34.88 |
-21:54:44.4 |
HIP 84869 |
19.72 |
| 2026-02-15 12:00 |
17:20:51.44 |
-21:54:59.0 |
HIP 84869 |
19.43 |
| 2026-02-16 00:00 |
17:21:07.85 |
-21:55:13.2 |
HIP 84869 |
19.88 |
| 2026-02-16 12:00 |
17:21:24.14 |
-21:55:27.3 |
HIP 84869 |
21.01 |
| 2026-02-17 00:00 |
17:21:40.28 |
-21:55:41.0 |
HIP 84869 |
22.71 |
| 2026-02-17 12:00 |
17:21:56.28 |
-21:55:54.5 |
HIP 84869 |
24.85 |
| 2026-02-18 00:00 |
17:22:12.14 |
-21:56:07.8 |
HIP 84869 |
27.30 |
| 2026-02-18 12:00 |
17:22:27.86 |
-21:56:20.8 |
HIP 85121 |
25.86 |
| 2026-02-19 00:00 |
17:22:43.43 |
-21:56:33.5 |
HIP 85121 |
23.54 |
| 2026-02-19 12:00 |
17:22:58.86 |
-21:56:46.0 |
HIP 85121 |
21.61 |
| 2026-02-20 00:00 |
17:23:14.14 |
-21:56:58.2 |
HIP 85121 |
20.14 |
| 2026-02-20 12:00 |
17:23:29.28 |
-21:57:10.2 |
HIP 85121 |
19.23 |
| 2026-02-21 00:00 |
17:23:44.26 |
-21:57:22.0 |
HIP 85121 |
18.93 |
| 2026-02-21 12:00 |
17:23:59.10 |
-21:57:33.5 |
HIP 85247 |
17.25 |
| 2026-02-22 00:00 |
17:24:13.78 |
-21:57:44.7 |
HIP 85247 |
14.00 |
| 2026-02-22 12:00 |
17:24:28.32 |
-21:57:55.8 |
HIP 85247 |
10.89 |
| 2026-02-23 00:00 |
17:24:42.69 |
-21:58:06.6 |
HIP 85247 |
8.01 |
| 2026-02-23 12:00 |
17:24:56.92 |
-21:58:17.1 |
HIP 85247 |
5.69 |
| 2026-02-24 00:00 |
17:25:10.99 |
-21:58:27.5 |
HIP 85247 |
4.73 |