P/2006 HR30 (Siding Spring)
| Parameter |
Value |
| Designation |
P/2006 HR30 (Siding Spring) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2007-01-02T06:46:18.693120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:56Z |
| Obs used |
3059 |
| NEO |
Yes |
| M1 |
13.900 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2006-11-07.0000000 |
| e |
0.84311855 |
| q (au) |
1.226428 |
| a (au) |
7.817544 |
| i (deg) |
31.884499 |
| Ω (om, deg) |
309.952160 |
| ω (w, deg) |
117.413876 |
| M (ma, deg) |
357.462130 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.237 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.237 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.665 |
| k |
0.800 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
19:16:51.87 |
-36:50:23.7 |
HIP 94651 |
16.64 |
| 2026-02-03 12:00 |
19:17:09.58 |
-36:49:58.7 |
HIP 94651 |
20.08 |
| 2026-02-04 00:00 |
19:17:27.24 |
-36:49:34.1 |
HIP 94956 |
23.28 |
| 2026-02-04 12:00 |
19:17:44.86 |
-36:49:09.8 |
HIP 94956 |
19.91 |
| 2026-02-05 00:00 |
19:18:02.44 |
-36:48:45.7 |
HIP 94956 |
16.62 |
| 2026-02-05 12:00 |
19:18:19.97 |
-36:48:22.0 |
HIP 94956 |
13.46 |
| 2026-02-06 00:00 |
19:18:37.45 |
-36:47:58.5 |
HIP 94956 |
10.55 |
| 2026-02-06 12:00 |
19:18:54.89 |
-36:47:35.4 |
HIP 94956 |
8.12 |
| 2026-02-07 00:00 |
19:19:12.29 |
-36:47:12.5 |
HIP 94956 |
6.73 |
| 2026-02-07 12:00 |
19:19:29.63 |
-36:46:50.0 |
HIP 94956 |
7.01 |
| 2026-02-08 00:00 |
19:19:46.93 |
-36:46:27.8 |
HIP 94966 |
7.66 |
| 2026-02-08 12:00 |
19:20:04.18 |
-36:46:05.8 |
HIP 94966 |
9.37 |
| 2026-02-09 00:00 |
19:20:21.38 |
-36:45:44.2 |
HIP 94966 |
11.87 |
| 2026-02-09 12:00 |
19:20:38.53 |
-36:45:23.0 |
HIP 94966 |
14.76 |
| 2026-02-10 00:00 |
19:20:55.62 |
-36:45:02.0 |
HIP 94966 |
17.85 |
| 2026-02-10 12:00 |
19:21:12.67 |
-36:44:41.3 |
HIP 94966 |
21.03 |
| 2026-02-11 00:00 |
19:21:29.66 |
-36:44:21.0 |
HIP 94966 |
24.28 |
| 2026-02-11 12:00 |
19:21:46.60 |
-36:44:01.0 |
HIP 94966 |
27.56 |
| 2026-02-12 00:00 |
19:22:03.48 |
-36:43:41.3 |
HIP 95337 |
29.14 |
| 2026-02-12 12:00 |
19:22:20.30 |
-36:43:21.9 |
HIP 95337 |
27.17 |
| 2026-02-13 00:00 |
19:22:37.07 |
-36:43:02.9 |
HIP 95337 |
25.48 |
| 2026-02-13 12:00 |
19:22:53.78 |
-36:42:44.2 |
HIP 95337 |
24.16 |
| 2026-02-14 00:00 |
19:23:10.43 |
-36:42:25.8 |
HIP 95337 |
23.24 |
| 2026-02-14 12:00 |
19:23:27.03 |
-36:42:07.7 |
HIP 95337 |
22.78 |
| 2026-02-15 00:00 |
19:23:43.56 |
-36:41:50.0 |
HIP 95337 |
22.80 |
| 2026-02-15 12:00 |
19:24:00.03 |
-36:41:32.7 |
HIP 95337 |
23.28 |
| 2026-02-16 00:00 |
19:24:16.44 |
-36:41:15.6 |
HIP 95337 |
24.21 |
| 2026-02-16 12:00 |
19:24:32.79 |
-36:40:59.0 |
HIP 95337 |
25.52 |
| 2026-02-17 00:00 |
19:24:49.07 |
-36:40:42.6 |
HIP 95337 |
27.15 |
| 2026-02-17 12:00 |
19:25:05.29 |
-36:40:26.6 |
HIP 95337 |
29.05 |
| 2026-02-18 00:00 |
19:25:21.44 |
-36:40:10.9 |
HIP 95337 |
31.16 |
| 2026-02-18 12:00 |
19:25:37.53 |
-36:39:55.6 |
HIP 95337 |
33.44 |
| 2026-02-19 00:00 |
19:25:53.55 |
-36:39:40.7 |
HIP 95337 |
35.85 |
| 2026-02-19 12:00 |
19:26:09.50 |
-36:39:26.1 |
HIP 95743 |
33.76 |
| 2026-02-20 00:00 |
19:26:25.38 |
-36:39:11.8 |
HIP 95743 |
31.40 |
| 2026-02-20 12:00 |
19:26:41.20 |
-36:38:57.9 |
HIP 95743 |
29.21 |
| 2026-02-21 00:00 |
19:26:56.94 |
-36:38:44.4 |
HIP 95743 |
27.21 |
| 2026-02-21 12:00 |
19:27:12.61 |
-36:38:31.2 |
HIP 95743 |
25.45 |
| 2026-02-22 00:00 |
19:27:28.21 |
-36:38:18.4 |
HIP 95743 |
23.98 |
| 2026-02-22 12:00 |
19:27:43.74 |
-36:38:06.0 |
HIP 95743 |
22.84 |
| 2026-02-23 00:00 |
19:27:59.19 |
-36:37:53.9 |
HIP 95743 |
22.09 |
| 2026-02-23 12:00 |
19:28:14.56 |
-36:37:42.1 |
HIP 95743 |
21.75 |
| 2026-02-24 00:00 |
19:28:29.87 |
-36:37:30.8 |
HIP 95743 |
21.84 |