| 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) |
| 2026-07-29 00:00 |
20:37:04.09 |
-11:02:17.2 |
HIP 101811 |
12.70 |
| 2026-07-29 12:00 |
20:36:54.09 |
-11:02:51.8 |
HIP 101811 |
15.18 |
| 2026-07-30 00:00 |
20:36:44.09 |
-11:03:26.7 |
HIP 101811 |
17.67 |
| 2026-07-30 12:00 |
20:36:34.08 |
-11:04:01.8 |
HIP 101811 |
20.17 |
| 2026-07-31 00:00 |
20:36:24.07 |
-11:04:37.2 |
HIP 101590 |
22.59 |
| 2026-07-31 12:00 |
20:36:14.05 |
-11:05:12.7 |
HIP 101590 |
20.49 |
| 2026-08-01 00:00 |
20:36:04.04 |
-11:05:48.4 |
HIP 101590 |
18.49 |
| 2026-08-01 12:00 |
20:35:54.03 |
-11:06:24.3 |
HIP 101590 |
16.62 |
| 2026-08-02 00:00 |
20:35:44.02 |
-11:07:00.4 |
HIP 101590 |
14.96 |
| 2026-08-02 12:00 |
20:35:34.02 |
-11:07:36.7 |
HIP 101590 |
13.56 |
| 2026-08-03 00:00 |
20:35:24.02 |
-11:08:13.2 |
HIP 101590 |
12.51 |
| 2026-08-03 12:00 |
20:35:14.02 |
-11:08:49.8 |
HIP 101590 |
11.92 |
| 2026-08-04 00:00 |
20:35:04.04 |
-11:09:26.7 |
HIP 101590 |
11.84 |
| 2026-08-04 12:00 |
20:34:54.06 |
-11:10:03.7 |
HIP 101590 |
12.29 |
| 2026-08-05 00:00 |
20:34:44.09 |
-11:10:40.8 |
HIP 101590 |
13.21 |
| 2026-08-05 12:00 |
20:34:34.13 |
-11:11:18.1 |
HIP 101590 |
14.51 |
| 2026-08-06 00:00 |
20:34:24.18 |
-11:11:55.6 |
HIP 101590 |
16.09 |
| 2026-08-06 12:00 |
20:34:14.25 |
-11:12:33.3 |
HIP 101590 |
17.89 |
| 2026-08-07 00:00 |
20:34:04.33 |
-11:13:11.0 |
HIP 101590 |
19.84 |
| 2026-08-07 12:00 |
20:33:54.42 |
-11:13:49.0 |
HIP 101590 |
21.90 |
| 2026-08-08 00:00 |
20:33:44.53 |
-11:14:27.0 |
HIP 101590 |
24.05 |
| 2026-08-08 12:00 |
20:33:34.66 |
-11:15:05.2 |
HIP 101590 |
26.25 |
| 2026-08-09 00:00 |
20:33:24.81 |
-11:15:43.6 |
HIP 101590 |
28.49 |
| 2026-08-09 12:00 |
20:33:14.98 |
-11:16:22.0 |
HIP 101590 |
30.77 |
| 2026-08-10 00:00 |
20:33:05.17 |
-11:17:00.6 |
HIP 101590 |
33.08 |
| 2026-08-10 12:00 |
20:32:55.38 |
-11:17:39.3 |
HIP 101590 |
35.40 |
| 2026-08-11 00:00 |
20:32:45.62 |
-11:18:18.1 |
HIP 101590 |
37.74 |
| 2026-08-11 12:00 |
20:32:35.88 |
-11:18:57.0 |
HIP 101277 |
36.49 |
| 2026-08-12 00:00 |
20:32:26.17 |
-11:19:36.0 |
HIP 101277 |
35.09 |
| 2026-08-12 12:00 |
20:32:16.49 |
-11:20:15.1 |
HIP 101277 |
33.82 |
| 2026-08-13 00:00 |
20:32:06.84 |
-11:20:54.3 |
HIP 101277 |
32.68 |
| 2026-08-13 12:00 |
20:31:57.21 |
-11:21:33.6 |
HIP 101277 |
31.69 |
| 2026-08-14 00:00 |
20:31:47.62 |
-11:22:12.9 |
HIP 101277 |
30.87 |
| 2026-08-14 12:00 |
20:31:38.06 |
-11:22:52.4 |
HIP 101277 |
30.21 |
| 2026-08-15 00:00 |
20:31:28.53 |
-11:23:31.9 |
HIP 101167 |
29.34 |
| 2026-08-15 12:00 |
20:31:19.04 |
-11:24:11.4 |
HIP 101167 |
27.54 |
| 2026-08-16 00:00 |
20:31:09.59 |
-11:24:51.0 |
HIP 101167 |
25.86 |
| 2026-08-16 12:00 |
20:31:00.17 |
-11:25:30.7 |
HIP 101167 |
24.29 |
| 2026-08-17 00:00 |
20:30:50.79 |
-11:26:10.4 |
HIP 101167 |
22.88 |
| 2026-08-17 12:00 |
20:30:41.46 |
-11:26:50.2 |
HIP 101167 |
21.64 |
| 2026-08-18 00:00 |
20:30:32.16 |
-11:27:30.0 |
HIP 101167 |
20.60 |
| 2026-08-18 12:00 |
20:30:22.90 |
-11:28:09.8 |
HIP 101167 |
19.79 |
| 2026-08-19 00:00 |
20:30:13.69 |
-11:28:49.7 |
HIP 101167 |
19.23 |