| Parameter |
Value |
| Designation |
47P/Ashbrook-Jackson |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-10-26T15:38:40.142400Z |
| Orbit solution date (soln_date, UTC) |
2026-04-14T14:49:55Z |
| Obs used |
2384 |
| NEO |
- |
| M1 |
13.100 |
| K1 |
4.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-11-29.0000000 |
| e |
0.31853138 |
| q (au) |
2.810020 |
| a (au) |
4.123477 |
| i (deg) |
13.040596 |
| Ω (om, deg) |
356.920741 |
| ω (w, deg) |
357.658335 |
| M (ma, deg) |
191.952899 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.013 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.013 |
| n |
6.000 |
| gf |
0.999 |
| gb |
-0.737 |
| k |
0.991 |
| δ90 |
9.999 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
02:29:14.50 |
+21:43:06.0 |
HIP 11584 |
7.50 |
| 2026-05-12 12:00 |
02:30:01.53 |
+21:47:43.7 |
HIP 11584 |
15.85 |
| 2026-05-13 00:00 |
02:30:48.56 |
+21:52:20.8 |
HIP 11728 |
15.30 |
| 2026-05-13 12:00 |
02:31:35.59 |
+21:56:57.3 |
HIP 11728 |
8.70 |
| 2026-05-14 00:00 |
02:32:22.63 |
+22:01:33.1 |
HIP 11797 |
2.69 |
| 2026-05-14 12:00 |
02:33:09.67 |
+22:06:08.3 |
HIP 11797 |
14.51 |
| 2026-05-15 00:00 |
02:33:56.71 |
+22:10:42.8 |
HIP 12017 |
22.71 |
| 2026-05-15 12:00 |
02:34:43.74 |
+22:15:16.7 |
HIP 12017 |
13.27 |
| 2026-05-16 00:00 |
02:35:30.78 |
+22:19:50.0 |
HIP 12017 |
10.73 |
| 2026-05-16 12:00 |
02:36:17.82 |
+22:24:22.7 |
HIP 12017 |
18.21 |
| 2026-05-17 00:00 |
02:37:04.85 |
+22:28:54.6 |
HIP 12017 |
28.73 |
| 2026-05-17 12:00 |
02:37:51.88 |
+22:33:26.0 |
HIP 12278 |
32.50 |
| 2026-05-18 00:00 |
02:38:38.91 |
+22:37:56.7 |
HIP 12257 |
31.89 |
| 2026-05-18 12:00 |
02:39:25.94 |
+22:42:26.7 |
HIP 12257 |
33.68 |
| 2026-05-19 00:00 |
02:40:12.96 |
+22:46:56.1 |
HIP 12556 |
36.90 |
| 2026-05-19 12:00 |
02:40:59.97 |
+22:51:24.8 |
HIP 12665 |
26.72 |
| 2026-05-20 00:00 |
02:41:46.98 |
+22:55:52.8 |
HIP 12665 |
15.06 |
| 2026-05-20 12:00 |
02:42:33.99 |
+23:00:20.2 |
HIP 12665 |
3.78 |
| 2026-05-21 00:00 |
02:43:20.99 |
+23:04:46.9 |
HIP 12665 |
8.69 |
| 2026-05-21 12:00 |
02:44:07.98 |
+23:09:13.0 |
HIP 12830 |
17.11 |
| 2026-05-22 00:00 |
02:44:54.96 |
+23:13:38.3 |
HIP 12830 |
8.44 |
| 2026-05-22 12:00 |
02:45:41.94 |
+23:18:03.0 |
HIP 12830 |
11.04 |
| 2026-05-23 00:00 |
02:46:28.91 |
+23:22:27.0 |
HIP 12830 |
21.06 |
| 2026-05-23 12:00 |
02:47:15.87 |
+23:26:50.4 |
HIP 13035 |
11.83 |
| 2026-05-24 00:00 |
02:48:02.82 |
+23:31:13.0 |
HIP 13035 |
10.20 |
| 2026-05-24 12:00 |
02:48:49.76 |
+23:35:35.0 |
HIP 13035 |
18.38 |
| 2026-05-25 00:00 |
02:49:36.69 |
+23:39:56.3 |
HIP 13242 |
11.32 |
| 2026-05-25 12:00 |
02:50:23.60 |
+23:44:16.9 |
HIP 13242 |
3.67 |
| 2026-05-26 00:00 |
02:51:10.51 |
+23:48:36.8 |
HIP 13277 |
5.66 |
| 2026-05-26 12:00 |
02:51:57.41 |
+23:52:56.1 |
HIP 13277 |
16.86 |
| 2026-05-27 00:00 |
02:52:44.30 |
+23:57:14.6 |
HIP 13547 |
24.45 |
| 2026-05-27 12:00 |
02:53:31.17 |
+24:01:32.5 |
HIP 13547 |
16.75 |
| 2026-05-28 00:00 |
02:54:18.03 |
+24:05:49.7 |
HIP 13547 |
15.15 |
| 2026-05-28 12:00 |
02:55:04.88 |
+24:10:06.2 |
HIP 13547 |
21.07 |
| 2026-05-29 00:00 |
02:55:51.72 |
+24:14:22.0 |
HIP 13549 |
30.02 |
| 2026-05-29 12:00 |
02:56:38.54 |
+24:18:37.1 |
HIP 13801 |
25.49 |
| 2026-05-30 00:00 |
02:57:25.35 |
+24:22:51.5 |
HIP 13867 |
21.89 |
| 2026-05-30 12:00 |
02:58:12.15 |
+24:27:05.2 |
HIP 13867 |
19.82 |
| 2026-05-31 00:00 |
02:58:58.93 |
+24:31:18.2 |
HIP 13867 |
23.86 |
| 2026-05-31 12:00 |
02:59:45.70 |
+24:35:30.6 |
HIP 13867 |
31.74 |
| 2026-06-01 00:00 |
03:00:32.45 |
+24:39:42.2 |
HIP 14080 |
30.61 |
| 2026-06-01 12:00 |
03:01:19.18 |
+24:43:53.1 |
HIP 14080 |
23.79 |
| 2026-06-02 00:00 |
03:02:05.90 |
+24:48:03.4 |
HIP 14080 |
21.34 |