| Parameter |
Value |
| Designation |
80P/Peters-Hartley |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-11-10T06:46:41.424960Z |
| Orbit solution date (soln_date, UTC) |
2024-08-26T13:12:38Z |
| Obs used |
179 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
15.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-04-13.0000000 |
| e |
0.59940950 |
| q (au) |
1.611763 |
| a (au) |
4.023467 |
| i (deg) |
29.931105 |
| Ω (om, deg) |
259.844351 |
| ω (w, deg) |
339.165604 |
| M (ma, deg) |
108.045831 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.621 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.621 |
| n |
6.000 |
| gf |
0.874 |
| gb |
-1.000 |
| k |
0.994 |
| δ90 |
1.000 |
| 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 |
03:09:54.24 |
+30:24:39.8 |
HIP 14805 |
23.80 |
| 2026-05-12 12:00 |
03:10:16.85 |
+30:25:32.4 |
HIP 14805 |
21.40 |
| 2026-05-13 00:00 |
03:10:39.46 |
+30:26:25.1 |
HIP 14805 |
19.97 |
| 2026-05-13 12:00 |
03:11:02.06 |
+30:27:17.9 |
HIP 14805 |
19.72 |
| 2026-05-14 00:00 |
03:11:24.66 |
+30:28:11.0 |
HIP 14805 |
20.70 |
| 2026-05-14 12:00 |
03:11:47.26 |
+30:29:04.2 |
HIP 14805 |
22.74 |
| 2026-05-15 00:00 |
03:12:09.85 |
+30:29:57.6 |
HIP 14805 |
25.59 |
| 2026-05-15 12:00 |
03:12:32.43 |
+30:30:51.2 |
HIP 14805 |
29.02 |
| 2026-05-16 00:00 |
03:12:55.01 |
+30:31:44.9 |
HIP 15154 |
31.36 |
| 2026-05-16 12:00 |
03:13:17.59 |
+30:32:38.8 |
HIP 15154 |
26.46 |
| 2026-05-17 00:00 |
03:13:40.15 |
+30:33:32.8 |
HIP 15154 |
21.59 |
| 2026-05-17 12:00 |
03:14:02.71 |
+30:34:27.0 |
HIP 15154 |
16.77 |
| 2026-05-18 00:00 |
03:14:25.25 |
+30:35:21.3 |
HIP 15154 |
12.04 |
| 2026-05-18 12:00 |
03:14:47.79 |
+30:36:15.8 |
HIP 15154 |
7.59 |
| 2026-05-19 00:00 |
03:15:10.32 |
+30:37:10.4 |
HIP 15154 |
4.36 |
| 2026-05-19 12:00 |
03:15:32.83 |
+30:38:05.1 |
HIP 15154 |
5.39 |
| 2026-05-20 00:00 |
03:15:55.33 |
+30:39:00.0 |
HIP 15154 |
9.37 |
| 2026-05-20 12:00 |
03:16:17.82 |
+30:39:55.0 |
HIP 15154 |
13.96 |
| 2026-05-21 00:00 |
03:16:40.30 |
+30:40:50.1 |
HIP 15154 |
18.72 |
| 2026-05-21 12:00 |
03:17:02.76 |
+30:41:45.4 |
HIP 15266 |
20.16 |
| 2026-05-22 00:00 |
03:17:25.21 |
+30:42:40.8 |
HIP 15266 |
20.17 |
| 2026-05-22 12:00 |
03:17:47.64 |
+30:43:36.2 |
HIP 15385 |
20.08 |
| 2026-05-23 00:00 |
03:18:10.05 |
+30:44:31.8 |
HIP 15385 |
17.87 |
| 2026-05-23 12:00 |
03:18:32.45 |
+30:45:27.5 |
HIP 15385 |
16.83 |
| 2026-05-24 00:00 |
03:18:54.83 |
+30:46:23.3 |
HIP 15385 |
17.17 |
| 2026-05-24 12:00 |
03:19:17.19 |
+30:47:19.2 |
HIP 15385 |
18.82 |
| 2026-05-25 00:00 |
03:19:39.53 |
+30:48:15.2 |
HIP 15385 |
21.47 |
| 2026-05-25 12:00 |
03:20:01.85 |
+30:49:11.3 |
HIP 15636 |
16.94 |
| 2026-05-26 00:00 |
03:20:24.15 |
+30:50:07.5 |
HIP 15636 |
12.55 |
| 2026-05-26 12:00 |
03:20:46.43 |
+30:51:03.8 |
HIP 15636 |
8.70 |
| 2026-05-27 00:00 |
03:21:08.69 |
+30:52:00.2 |
HIP 15636 |
6.45 |
| 2026-05-27 12:00 |
03:21:30.93 |
+30:52:56.7 |
HIP 15636 |
7.40 |
| 2026-05-28 00:00 |
03:21:53.14 |
+30:53:53.2 |
HIP 15636 |
10.74 |
| 2026-05-28 12:00 |
03:22:15.33 |
+30:54:49.8 |
HIP 15636 |
14.93 |
| 2026-05-29 00:00 |
03:22:37.50 |
+30:55:46.5 |
HIP 15781 |
10.47 |
| 2026-05-29 12:00 |
03:22:59.64 |
+30:56:43.3 |
HIP 15781 |
5.70 |
| 2026-05-30 00:00 |
03:23:21.76 |
+30:57:40.2 |
HIP 15781 |
1.45 |
| 2026-05-30 12:00 |
03:23:43.85 |
+30:58:37.1 |
HIP 15781 |
4.30 |
| 2026-05-31 00:00 |
03:24:05.92 |
+30:59:34.1 |
HIP 15781 |
9.02 |
| 2026-05-31 12:00 |
03:24:27.96 |
+31:00:31.2 |
HIP 15781 |
13.81 |
| 2026-06-01 00:00 |
03:24:49.97 |
+31:01:28.3 |
HIP 15984 |
14.04 |
| 2026-06-01 12:00 |
03:25:11.95 |
+31:02:25.5 |
HIP 15984 |
10.46 |
| 2026-06-02 00:00 |
03:25:33.91 |
+31:03:22.7 |
HIP 15984 |
8.24 |