| Parameter |
Value |
| Designation |
269P/Jedicke |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2014-11-25T22:04:56.112960Z |
| Orbit solution date (soln_date, UTC) |
2023-05-03T22:44:27Z |
| Obs used |
904 |
| NEO |
- |
| M1 |
6.700 |
| K1 |
12.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2009-11-07.0000000 |
| e |
0.43469217 |
| q (au) |
4.077250 |
| a (au) |
7.212443 |
| i (deg) |
6.611643 |
| Ω (om, deg) |
248.991032 |
| ω (w, deg) |
223.915918 |
| M (ma, deg) |
266.123247 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.141 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.141 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.932 |
| 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 |
| 2012-09-11 |
2013-11-03 |
+7.2265 |
-4.196 |
| 2013-11-03 |
2014-11-25 |
+12.8920 |
-8.168 |
| 2014-12-14 |
2016-03-13 |
+7.6679 |
-4.901 |
| 2016-03-13 |
2017-03-21 |
+16.4470 |
-11.763 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
20:22:37.17 |
-12:09:04.1 |
HIP 100483 |
13.85 |
| 2026-09-20 12:00 |
20:22:32.71 |
-12:09:36.8 |
HIP 100483 |
13.32 |
| 2026-09-21 00:00 |
20:22:28.35 |
-12:10:09.2 |
HIP 100483 |
12.89 |
| 2026-09-21 12:00 |
20:22:24.08 |
-12:10:41.3 |
HIP 100483 |
12.55 |
| 2026-09-22 00:00 |
20:22:19.91 |
-12:11:13.3 |
HIP 100483 |
12.31 |
| 2026-09-22 12:00 |
20:22:15.84 |
-12:11:44.9 |
HIP 100483 |
12.17 |
| 2026-09-23 00:00 |
20:22:11.86 |
-12:12:16.4 |
HIP 100483 |
12.13 |
| 2026-09-23 12:00 |
20:22:07.99 |
-12:12:47.5 |
HIP 100483 |
12.17 |
| 2026-09-24 00:00 |
20:22:04.21 |
-12:13:18.4 |
HIP 100483 |
12.30 |
| 2026-09-24 12:00 |
20:22:00.54 |
-12:13:49.1 |
HIP 100483 |
12.51 |
| 2026-09-25 00:00 |
20:21:56.96 |
-12:14:19.5 |
HIP 100483 |
12.78 |
| 2026-09-25 12:00 |
20:21:53.48 |
-12:14:49.6 |
HIP 100483 |
13.10 |
| 2026-09-26 00:00 |
20:21:50.10 |
-12:15:19.5 |
HIP 100483 |
13.47 |
| 2026-09-26 12:00 |
20:21:46.83 |
-12:15:49.1 |
HIP 100483 |
13.88 |
| 2026-09-27 00:00 |
20:21:43.65 |
-12:16:18.4 |
HIP 100483 |
14.32 |
| 2026-09-27 12:00 |
20:21:40.57 |
-12:16:47.4 |
HIP 100483 |
14.79 |
| 2026-09-28 00:00 |
20:21:37.60 |
-12:17:16.2 |
HIP 100483 |
15.27 |
| 2026-09-28 12:00 |
20:21:34.73 |
-12:17:44.7 |
HIP 100483 |
15.76 |
| 2026-09-29 00:00 |
20:21:31.96 |
-12:18:12.9 |
HIP 100483 |
16.26 |
| 2026-09-29 12:00 |
20:21:29.29 |
-12:18:40.9 |
HIP 100483 |
16.76 |
| 2026-09-30 00:00 |
20:21:26.72 |
-12:19:08.5 |
HIP 100483 |
17.26 |
| 2026-09-30 12:00 |
20:21:24.26 |
-12:19:35.8 |
HIP 100483 |
17.76 |
| 2026-10-01 00:00 |
20:21:21.90 |
-12:20:02.9 |
HIP 100483 |
18.25 |
| 2026-10-01 12:00 |
20:21:19.64 |
-12:20:29.7 |
HIP 100483 |
18.73 |
| 2026-10-02 00:00 |
20:21:17.49 |
-12:20:56.1 |
HIP 100483 |
19.20 |
| 2026-10-02 12:00 |
20:21:15.44 |
-12:21:22.3 |
HIP 100483 |
19.66 |
| 2026-10-03 00:00 |
20:21:13.50 |
-12:21:48.2 |
HIP 100483 |
20.10 |
| 2026-10-03 12:00 |
20:21:11.66 |
-12:22:13.8 |
HIP 100483 |
20.53 |
| 2026-10-04 00:00 |
20:21:09.92 |
-12:22:39.0 |
HIP 100483 |
20.94 |
| 2026-10-04 12:00 |
20:21:08.29 |
-12:23:04.0 |
HIP 100483 |
21.34 |
| 2026-10-05 00:00 |
20:21:06.77 |
-12:23:28.6 |
HIP 100483 |
21.72 |
| 2026-10-05 12:00 |
20:21:05.35 |
-12:23:52.9 |
HIP 100483 |
22.08 |
| 2026-10-06 00:00 |
20:21:04.03 |
-12:24:16.9 |
HIP 100310 |
22.07 |
| 2026-10-06 12:00 |
20:21:02.82 |
-12:24:40.6 |
HIP 100310 |
21.61 |
| 2026-10-07 00:00 |
20:21:01.72 |
-12:25:04.0 |
HIP 100310 |
21.16 |
| 2026-10-07 12:00 |
20:21:00.73 |
-12:25:27.0 |
HIP 100310 |
20.73 |
| 2026-10-08 00:00 |
20:20:59.84 |
-12:25:49.7 |
HIP 100310 |
20.31 |
| 2026-10-08 12:00 |
20:20:59.05 |
-12:26:12.1 |
HIP 100310 |
19.90 |
| 2026-10-09 00:00 |
20:20:58.38 |
-12:26:34.1 |
HIP 100310 |
19.51 |
| 2026-10-09 12:00 |
20:20:57.81 |
-12:26:55.8 |
HIP 100310 |
19.12 |
| 2026-10-10 00:00 |
20:20:57.35 |
-12:27:17.2 |
HIP 100310 |
18.75 |
| 2026-10-10 12:00 |
20:20:56.99 |
-12:27:38.2 |
HIP 100310 |
18.39 |
| 2026-10-11 00:00 |
20:20:56.75 |
-12:27:58.9 |
HIP 100310 |
18.04 |