119P/Parker-Hartley

Metadata

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

119P/Parker-Hartley · Magnitude (Full range)

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)
2026-05-12 00:00 16:43:20.60 -16:47:48.0 HIP 81723 26.74
2026-05-12 12:00 16:43:04.03 -16:47:17.9 HIP 81723 23.19
2026-05-13 00:00 16:42:47.36 -16:46:47.7 HIP 81723 19.78
2026-05-13 12:00 16:42:30.59 -16:46:17.6 HIP 81723 16.62
2026-05-14 00:00 16:42:13.71 -16:45:47.5 HIP 81723 13.91
2026-05-14 12:00 16:41:56.74 -16:45:17.5 HIP 81723 11.99
2026-05-15 00:00 16:41:39.67 -16:44:47.5 HIP 81723 11.29
2026-05-15 12:00 16:41:22.51 -16:44:17.6 HIP 81723 12.04
2026-05-16 00:00 16:41:05.25 -16:43:47.7 HIP 81723 14.04
2026-05-16 12:00 16:40:47.91 -16:43:17.8 HIP 81723 16.86
2026-05-17 00:00 16:40:30.49 -16:42:48.1 HIP 81723 20.17
2026-05-17 12:00 16:40:12.98 -16:42:18.4 HIP 81723 23.78
2026-05-18 00:00 16:39:55.40 -16:41:48.7 HIP 81723 27.58
2026-05-18 12:00 16:39:37.74 -16:41:19.2 HIP 81409 30.43
2026-05-19 00:00 16:39:20.00 -16:40:49.7 HIP 81409 26.63
2026-05-19 12:00 16:39:02.20 -16:40:20.4 HIP 81409 22.97
2026-05-20 00:00 16:38:44.33 -16:39:51.1 HIP 81409 19.56
2026-05-20 12:00 16:38:26.39 -16:39:21.9 HIP 81409 16.55
2026-05-21 00:00 16:38:08.39 -16:38:52.8 HIP 81409 14.23
2026-05-21 12:00 16:37:50.34 -16:38:23.9 HIP 81409 12.98
2026-05-22 00:00 16:37:32.23 -16:37:55.1 HIP 81409 13.13
2026-05-22 12:00 16:37:14.07 -16:37:26.3 HIP 81409 14.64
2026-05-23 00:00 16:36:55.85 -16:36:57.8 HIP 81409 17.17
2026-05-23 12:00 16:36:37.60 -16:36:29.3 HIP 81409 20.34
2026-05-24 00:00 16:36:19.29 -16:36:01.0 HIP 81409 23.92
2026-05-24 12:00 16:36:00.95 -16:35:32.8 HIP 81220 21.68
2026-05-25 00:00 16:35:42.57 -16:35:04.8 HIP 81220 19.71
2026-05-25 12:00 16:35:24.15 -16:34:36.9 HIP 81220 18.60
2026-05-26 00:00 16:35:05.71 -16:34:09.2 HIP 81220 18.53
2026-05-26 12:00 16:34:47.23 -16:33:41.6 HIP 81220 19.51
2026-05-27 00:00 16:34:28.72 -16:33:14.2 HIP 81220 21.39
2026-05-27 12:00 16:34:10.20 -16:32:47.0 HIP 81220 23.98
2026-05-28 00:00 16:33:51.65 -16:32:19.9 HIP 81220 27.06
2026-05-28 12:00 16:33:33.08 -16:31:53.1 HIP 81220 30.49
2026-05-29 00:00 16:33:14.50 -16:31:26.4 HIP 80894 30.68
2026-05-29 12:00 16:32:55.90 -16:31:00.0 HIP 80894 26.40
2026-05-30 00:00 16:32:37.30 -16:30:33.6 HIP 80894 22.19
2026-05-30 12:00 16:32:18.69 -16:30:07.5 HIP 80894 18.10
2026-05-31 00:00 16:32:00.07 -16:29:41.7 HIP 80894 14.26
2026-05-31 12:00 16:31:41.46 -16:29:16.0 HIP 80894 10.90
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