| Parameter |
Value |
| Designation |
489P/Denning |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2007-04-20T21:15:31.694400Z |
| Orbit solution date (soln_date, UTC) |
2024-10-11T13:45:58Z |
| Obs used |
302 |
| NEO |
- |
| M1 |
7.600 |
| K1 |
49.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2007-04-17T03:02:00.096000Z |
| Discovery magnitude (MPC) |
18.70 |
| Discovery observatory (MPC) |
704 · Lincoln Laboratory ETS, New Mexico |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2002-08-18.0000000 |
| e |
0.64560760 |
| q (au) |
1.574689 |
| a (au) |
4.443348 |
| i (deg) |
4.007070 |
| Ω (om, deg) |
22.578905 |
| ω (w, deg) |
107.960844 |
| M (ma, deg) |
180.384811 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.591 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.591 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
12:43:04.89 |
-05:35:13.9 |
HIP 62057 |
9.21 |
| 2026-05-12 12:00 |
12:43:04.22 |
-05:36:05.4 |
HIP 62057 |
8.37 |
| 2026-05-13 00:00 |
12:43:03.95 |
-05:36:58.7 |
HIP 62057 |
7.51 |
| 2026-05-13 12:00 |
12:43:04.05 |
-05:37:53.8 |
HIP 62057 |
6.60 |
| 2026-05-14 00:00 |
12:43:04.54 |
-05:38:50.6 |
HIP 62057 |
5.64 |
| 2026-05-14 12:00 |
12:43:05.42 |
-05:39:49.3 |
HIP 62057 |
4.64 |
| 2026-05-15 00:00 |
12:43:06.67 |
-05:40:49.7 |
HIP 62057 |
3.60 |
| 2026-05-15 12:00 |
12:43:08.31 |
-05:41:51.8 |
HIP 62057 |
2.53 |
| 2026-05-16 00:00 |
12:43:10.32 |
-05:42:55.8 |
HIP 62057 |
1.51 |
| 2026-05-16 12:00 |
12:43:12.71 |
-05:44:01.4 |
HIP 62057 |
1.04 |
| 2026-05-17 00:00 |
12:43:15.47 |
-05:45:08.9 |
HIP 62057 |
1.83 |
| 2026-05-17 12:00 |
12:43:18.61 |
-05:46:18.1 |
HIP 62057 |
3.10 |
| 2026-05-18 00:00 |
12:43:22.11 |
-05:47:29.0 |
HIP 62057 |
4.54 |
| 2026-05-18 12:00 |
12:43:25.99 |
-05:48:41.6 |
HIP 62057 |
6.07 |
| 2026-05-19 00:00 |
12:43:30.23 |
-05:49:56.0 |
HIP 62057 |
7.70 |
| 2026-05-19 12:00 |
12:43:34.84 |
-05:51:12.1 |
HIP 62057 |
9.41 |
| 2026-05-20 00:00 |
12:43:39.82 |
-05:52:29.9 |
HIP 62057 |
11.20 |
| 2026-05-20 12:00 |
12:43:45.15 |
-05:53:49.4 |
HIP 62057 |
13.07 |
| 2026-05-21 00:00 |
12:43:50.84 |
-05:55:10.6 |
HIP 62057 |
15.03 |
| 2026-05-21 12:00 |
12:43:56.88 |
-05:56:33.5 |
HIP 62057 |
17.07 |
| 2026-05-22 00:00 |
12:44:03.28 |
-05:57:58.0 |
HIP 62190 |
15.93 |
| 2026-05-22 12:00 |
12:44:10.03 |
-05:59:24.1 |
HIP 62190 |
13.76 |
| 2026-05-23 00:00 |
12:44:17.12 |
-06:00:51.9 |
HIP 62190 |
11.54 |
| 2026-05-23 12:00 |
12:44:24.56 |
-06:02:21.4 |
HIP 62190 |
9.29 |
| 2026-05-24 00:00 |
12:44:32.34 |
-06:03:52.4 |
HIP 62190 |
7.06 |
| 2026-05-24 12:00 |
12:44:40.46 |
-06:05:25.0 |
HIP 62190 |
5.00 |
| 2026-05-25 00:00 |
12:44:48.92 |
-06:06:59.2 |
HIP 62190 |
3.64 |
| 2026-05-25 12:00 |
12:44:57.70 |
-06:08:35.0 |
HIP 62190 |
3.96 |
| 2026-05-26 00:00 |
12:45:06.82 |
-06:10:12.3 |
HIP 62190 |
5.80 |
| 2026-05-26 12:00 |
12:45:16.27 |
-06:11:51.1 |
HIP 62190 |
8.28 |
| 2026-05-27 00:00 |
12:45:26.03 |
-06:13:31.5 |
HIP 62190 |
11.04 |
| 2026-05-27 12:00 |
12:45:36.12 |
-06:15:13.4 |
HIP 62190 |
13.95 |
| 2026-05-28 00:00 |
12:45:46.53 |
-06:16:56.8 |
HIP 62190 |
16.99 |
| 2026-05-28 12:00 |
12:45:57.26 |
-06:18:41.7 |
HIP 62190 |
20.14 |
| 2026-05-29 00:00 |
12:46:08.29 |
-06:20:28.0 |
HIP 62421 |
21.28 |
| 2026-05-29 12:00 |
12:46:19.64 |
-06:22:15.8 |
HIP 62421 |
18.80 |
| 2026-05-30 00:00 |
12:46:31.29 |
-06:24:05.0 |
HIP 62421 |
16.56 |
| 2026-05-30 12:00 |
12:46:43.25 |
-06:25:55.6 |
HIP 62421 |
14.72 |
| 2026-05-31 00:00 |
12:46:55.51 |
-06:27:47.7 |
HIP 62421 |
13.52 |
| 2026-05-31 12:00 |
12:47:08.06 |
-06:29:41.2 |
HIP 62421 |
13.19 |
| 2026-06-01 00:00 |
12:47:20.91 |
-06:31:36.0 |
HIP 62421 |
13.85 |
| 2026-06-01 12:00 |
12:47:34.06 |
-06:33:32.2 |
HIP 62421 |
15.44 |
| 2026-06-02 00:00 |
12:47:47.50 |
-06:35:29.8 |
HIP 62421 |
17.75 |