| Parameter |
Value |
| Designation |
119P/Parker-Hartley |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-04-03T23:02:16.448640Z |
| Orbit solution date (soln_date, UTC) |
2024-09-01T19:42:26Z |
| Obs used |
3237 |
| NEO |
- |
| M1 |
9.600 |
| K1 |
13.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-08-20.0000000 |
| e |
0.29594027 |
| q (au) |
3.023931 |
| a (au) |
4.294992 |
| i (deg) |
5.183509 |
| Ω (om, deg) |
243.678154 |
| ω (w, deg) |
181.859700 |
| M (ma, deg) |
55.701021 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.651 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.651 |
| n |
6.000 |
| gf |
0.801 |
| gb |
-0.500 |
| k |
0.964 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2021-05-28 |
2021-10-23 |
+0.9742 |
-0.715 |
| 2021-10-23 |
2024-05-06 |
-1.5544 |
+0.897 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
16:31:22.84 |
-16:28:50.6 |
HIP 80894 |
8.64 |
| 2026-06-01 12:00 |
16:31:04.23 |
-16:28:25.3 |
HIP 80894 |
8.40 |
| 2026-06-02 00:00 |
16:30:45.63 |
-16:28:00.3 |
HIP 80894 |
10.31 |
| 2026-06-02 12:00 |
16:30:27.04 |
-16:27:35.6 |
HIP 80894 |
13.50 |
| 2026-06-03 00:00 |
16:30:08.46 |
-16:27:11.1 |
HIP 80894 |
17.26 |
| 2026-06-03 12:00 |
16:29:49.89 |
-16:26:46.8 |
HIP 80776 |
17.81 |
| 2026-06-04 00:00 |
16:29:31.35 |
-16:26:22.8 |
HIP 80776 |
17.00 |
| 2026-06-04 12:00 |
16:29:12.82 |
-16:25:59.0 |
HIP 80776 |
17.35 |
| 2026-06-05 00:00 |
16:28:54.32 |
-16:25:35.5 |
HIP 80677 |
15.80 |
| 2026-06-05 12:00 |
16:28:35.85 |
-16:25:12.3 |
HIP 80677 |
13.35 |
| 2026-06-06 00:00 |
16:28:17.41 |
-16:24:49.4 |
HIP 80677 |
12.10 |
| 2026-06-06 12:00 |
16:27:58.99 |
-16:24:26.7 |
HIP 80677 |
12.41 |
| 2026-06-07 00:00 |
16:27:40.62 |
-16:24:04.3 |
HIP 80677 |
14.18 |
| 2026-06-07 12:00 |
16:27:22.28 |
-16:23:42.2 |
HIP 80677 |
16.94 |
| 2026-06-08 00:00 |
16:27:03.98 |
-16:23:20.4 |
HIP 80677 |
20.29 |
| 2026-06-08 12:00 |
16:26:45.73 |
-16:22:58.9 |
HIP 80677 |
23.98 |
| 2026-06-09 00:00 |
16:26:27.52 |
-16:22:37.7 |
HIP 80447 |
20.33 |
| 2026-06-09 12:00 |
16:26:09.36 |
-16:22:16.9 |
HIP 80447 |
16.63 |
| 2026-06-10 00:00 |
16:25:51.25 |
-16:21:56.3 |
HIP 80447 |
13.37 |
| 2026-06-10 12:00 |
16:25:33.20 |
-16:21:36.1 |
HIP 80447 |
10.90 |
| 2026-06-11 00:00 |
16:25:15.21 |
-16:21:16.2 |
HIP 80447 |
9.83 |
| 2026-06-11 12:00 |
16:24:57.27 |
-16:20:56.6 |
HIP 80447 |
10.59 |
| 2026-06-12 00:00 |
16:24:39.40 |
-16:20:37.4 |
HIP 80447 |
12.83 |
| 2026-06-12 12:00 |
16:24:21.60 |
-16:20:18.6 |
HIP 80447 |
15.94 |
| 2026-06-13 00:00 |
16:24:03.86 |
-16:20:00.1 |
HIP 80447 |
19.48 |
| 2026-06-13 12:00 |
16:23:46.20 |
-16:19:42.0 |
HIP 80447 |
23.25 |
| 2026-06-14 00:00 |
16:23:28.61 |
-16:19:24.2 |
HIP 80447 |
27.15 |
| 2026-06-14 12:00 |
16:23:11.10 |
-16:19:06.8 |
HIP 80447 |
31.12 |
| 2026-06-15 00:00 |
16:22:53.67 |
-16:18:49.8 |
HIP 80447 |
35.13 |
| 2026-06-15 12:00 |
16:22:36.33 |
-16:18:33.2 |
HIP 80447 |
39.16 |
| 2026-06-16 00:00 |
16:22:19.06 |
-16:18:17.0 |
HIP 80447 |
43.20 |
| 2026-06-16 12:00 |
16:22:01.89 |
-16:18:01.1 |
HIP 80240 |
44.87 |
| 2026-06-17 00:00 |
16:21:44.81 |
-16:17:45.7 |
HIP 80240 |
46.41 |
| 2026-06-17 12:00 |
16:21:27.82 |
-16:17:30.7 |
HIP 80240 |
48.23 |
| 2026-06-18 00:00 |
16:21:10.93 |
-16:17:16.1 |
HIP 80072 |
48.43 |
| 2026-06-18 12:00 |
16:20:54.14 |
-16:17:01.9 |
HIP 80072 |
48.10 |
| 2026-06-19 00:00 |
16:20:37.45 |
-16:16:48.1 |
HIP 79972 |
47.35 |
| 2026-06-19 12:00 |
16:20:20.86 |
-16:16:34.7 |
HIP 79972 |
45.82 |
| 2026-06-20 00:00 |
16:20:04.38 |
-16:16:21.8 |
HIP 79972 |
44.61 |
| 2026-06-20 12:00 |
16:19:48.01 |
-16:16:09.3 |
HIP 79972 |
43.74 |
| 2026-06-21 00:00 |
16:19:31.75 |
-16:15:57.2 |
HIP 79972 |
43.22 |
| 2026-06-21 12:00 |
16:19:15.60 |
-16:15:45.6 |
HIP 79972 |
43.06 |
| 2026-06-22 00:00 |
16:18:59.57 |
-16:15:34.5 |
HIP 79972 |
43.25 |