| Parameter |
Value |
| Designation |
C/2019 J2 (Palomar) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-07-19T17:09:39.836160Z |
| Orbit solution date (soln_date, UTC) |
2021-09-04T23:42:59Z |
| Obs used |
312 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
22.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2019-05-09T11:22:13.987200Z |
| Discovery magnitude (MPC) |
16.86 r |
| Discovery observatory (MPC) |
I41 · Palomar Mountain–ZTF |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2019-06-10.0000000 |
| e |
0.99767395 |
| q (au) |
1.727002 |
| a (au) |
742.459732 |
| i (deg) |
105.135744 |
| Ω (om, deg) |
25.468130 |
| ω (w, deg) |
98.695628 |
| M (ma, deg) |
359.998065 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.283 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.283 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2019-04-27 |
2019-07-19 |
-32.7489 |
+9.328 |
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 |
09:19:46.33 |
-50:19:12.8 |
HIP 45765 |
13.71 |
| 2026-06-01 12:00 |
09:19:49.10 |
-50:18:01.1 |
HIP 45765 |
14.86 |
| 2026-06-02 00:00 |
09:19:51.93 |
-50:16:49.7 |
HIP 45765 |
16.01 |
| 2026-06-02 12:00 |
09:19:54.83 |
-50:15:38.8 |
HIP 45765 |
17.17 |
| 2026-06-03 00:00 |
09:19:57.80 |
-50:14:28.3 |
HIP 45765 |
18.34 |
| 2026-06-03 12:00 |
09:20:00.84 |
-50:13:18.2 |
HIP 45765 |
19.52 |
| 2026-06-04 00:00 |
09:20:03.94 |
-50:12:08.6 |
HIP 45819 |
18.32 |
| 2026-06-04 12:00 |
09:20:07.11 |
-50:10:59.4 |
HIP 45819 |
17.08 |
| 2026-06-05 00:00 |
09:20:10.35 |
-50:09:50.7 |
HIP 45819 |
15.84 |
| 2026-06-05 12:00 |
09:20:13.65 |
-50:08:42.5 |
HIP 45819 |
14.61 |
| 2026-06-06 00:00 |
09:20:17.01 |
-50:07:34.6 |
HIP 45819 |
13.40 |
| 2026-06-06 12:00 |
09:20:20.45 |
-50:06:27.3 |
HIP 45819 |
12.19 |
| 2026-06-07 00:00 |
09:20:23.94 |
-50:05:20.4 |
HIP 45819 |
11.01 |
| 2026-06-07 12:00 |
09:20:27.50 |
-50:04:14.0 |
HIP 45819 |
9.84 |
| 2026-06-08 00:00 |
09:20:31.12 |
-50:03:08.0 |
HIP 45819 |
8.71 |
| 2026-06-08 12:00 |
09:20:34.81 |
-50:02:02.6 |
HIP 45819 |
7.61 |
| 2026-06-09 00:00 |
09:20:38.56 |
-50:00:57.6 |
HIP 45819 |
6.58 |
| 2026-06-09 12:00 |
09:20:42.37 |
-49:59:53.1 |
HIP 45819 |
5.65 |
| 2026-06-10 00:00 |
09:20:46.25 |
-49:58:49.1 |
HIP 45819 |
4.87 |
| 2026-06-10 12:00 |
09:20:50.18 |
-49:57:45.6 |
HIP 45819 |
4.31 |
| 2026-06-11 00:00 |
09:20:54.18 |
-49:56:42.6 |
HIP 45819 |
4.08 |
| 2026-06-11 12:00 |
09:20:58.24 |
-49:55:40.1 |
HIP 45819 |
4.23 |
| 2026-06-12 00:00 |
09:21:02.35 |
-49:54:38.1 |
HIP 45819 |
4.71 |
| 2026-06-12 12:00 |
09:21:06.53 |
-49:53:36.6 |
HIP 45819 |
5.44 |
| 2026-06-13 00:00 |
09:21:10.77 |
-49:52:35.6 |
HIP 45819 |
6.34 |
| 2026-06-13 12:00 |
09:21:15.07 |
-49:51:35.2 |
HIP 45819 |
7.33 |
| 2026-06-14 00:00 |
09:21:19.42 |
-49:50:35.2 |
HIP 45819 |
8.39 |
| 2026-06-14 12:00 |
09:21:23.84 |
-49:49:35.8 |
HIP 45819 |
9.50 |
| 2026-06-15 00:00 |
09:21:28.31 |
-49:48:37.0 |
HIP 45819 |
10.63 |
| 2026-06-15 12:00 |
09:21:32.83 |
-49:47:38.6 |
HIP 45819 |
11.78 |
| 2026-06-16 00:00 |
09:21:37.42 |
-49:46:40.8 |
HIP 45819 |
12.94 |
| 2026-06-16 12:00 |
09:21:42.06 |
-49:45:43.6 |
HIP 45819 |
14.12 |
| 2026-06-17 00:00 |
09:21:46.76 |
-49:44:46.9 |
HIP 45819 |
15.30 |
| 2026-06-17 12:00 |
09:21:51.51 |
-49:43:50.7 |
HIP 45819 |
16.49 |
| 2026-06-18 00:00 |
09:21:56.31 |
-49:42:55.1 |
HIP 45819 |
17.68 |
| 2026-06-18 12:00 |
09:22:01.17 |
-49:42:00.1 |
HIP 45819 |
18.88 |
| 2026-06-19 00:00 |
09:22:06.08 |
-49:41:05.6 |
HIP 45819 |
20.08 |
| 2026-06-19 12:00 |
09:22:11.05 |
-49:40:11.6 |
HIP 45819 |
21.27 |
| 2026-06-20 00:00 |
09:22:16.07 |
-49:39:18.3 |
HIP 45819 |
22.47 |
| 2026-06-20 12:00 |
09:22:21.14 |
-49:38:25.5 |
HIP 45986 |
22.26 |
| 2026-06-21 00:00 |
09:22:26.26 |
-49:37:33.2 |
HIP 45986 |
21.28 |
| 2026-06-21 12:00 |
09:22:31.43 |
-49:36:41.6 |
HIP 45986 |
20.34 |
| 2026-06-22 00:00 |
09:22:36.66 |
-49:35:50.5 |
HIP 45986 |
19.43 |