251P/LINEAR
| Parameter |
Value |
| Designation |
251P/LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2004-06-19T01:47:38.279040Z |
| Orbit solution date (soln_date, UTC) |
2024-10-05T23:12:40Z |
| Obs used |
431 |
| NEO |
- |
| M1 |
12.000 |
| K1 |
24.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-04-11.0000000 |
| e |
0.50982311 |
| q (au) |
1.711672 |
| a (au) |
3.491948 |
| i (deg) |
23.507154 |
| Ω (om, deg) |
219.552911 |
| ω (w, deg) |
30.906733 |
| M (ma, deg) |
154.959455 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.255 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.255 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.719 |
| k |
0.978 |
| 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) |
| 2026-02-03 00:00 |
01:47:19.84 |
+10:33:24.1 |
HIP 8306 |
17.45 |
| 2026-02-03 12:00 |
01:47:35.10 |
+10:33:58.1 |
HIP 8306 |
17.87 |
| 2026-02-04 00:00 |
01:47:50.49 |
+10:34:33.0 |
HIP 8306 |
19.05 |
| 2026-02-04 12:00 |
01:48:06.03 |
+10:35:08.9 |
HIP 8306 |
20.88 |
| 2026-02-05 00:00 |
01:48:21.71 |
+10:35:45.6 |
HIP 8416 |
23.12 |
| 2026-02-05 12:00 |
01:48:37.52 |
+10:36:23.2 |
HIP 8416 |
23.51 |
| 2026-02-06 00:00 |
01:48:53.46 |
+10:37:01.7 |
HIP 8416 |
24.55 |
| 2026-02-06 12:00 |
01:49:09.54 |
+10:37:41.0 |
HIP 8416 |
26.19 |
| 2026-02-07 00:00 |
01:49:25.75 |
+10:38:21.3 |
HIP 8416 |
28.33 |
| 2026-02-07 12:00 |
01:49:42.10 |
+10:39:02.3 |
HIP 8588 |
29.16 |
| 2026-02-08 00:00 |
01:49:58.58 |
+10:39:44.3 |
HIP 8588 |
26.37 |
| 2026-02-08 12:00 |
01:50:15.18 |
+10:40:27.0 |
HIP 8588 |
23.93 |
| 2026-02-09 00:00 |
01:50:31.92 |
+10:41:10.6 |
HIP 8588 |
21.99 |
| 2026-02-09 12:00 |
01:50:48.79 |
+10:41:55.0 |
HIP 8708 |
19.32 |
| 2026-02-10 00:00 |
01:51:05.78 |
+10:42:40.2 |
HIP 8708 |
15.16 |
| 2026-02-10 12:00 |
01:51:22.90 |
+10:43:26.2 |
HIP 8708 |
11.04 |
| 2026-02-11 00:00 |
01:51:40.15 |
+10:44:13.0 |
HIP 8708 |
7.06 |
| 2026-02-11 12:00 |
01:51:57.52 |
+10:45:00.6 |
HIP 8708 |
3.83 |
| 2026-02-12 00:00 |
01:52:15.01 |
+10:45:49.0 |
HIP 8708 |
4.16 |
| 2026-02-12 12:00 |
01:52:32.63 |
+10:46:38.1 |
HIP 8708 |
7.65 |
| 2026-02-13 00:00 |
01:52:50.37 |
+10:47:28.0 |
HIP 8708 |
11.80 |
| 2026-02-13 12:00 |
01:53:08.23 |
+10:48:18.6 |
HIP 8708 |
16.13 |
| 2026-02-14 00:00 |
01:53:26.21 |
+10:49:10.0 |
HIP 8859 |
14.53 |
| 2026-02-14 12:00 |
01:53:44.31 |
+10:50:02.0 |
HIP 8904 |
13.38 |
| 2026-02-15 00:00 |
01:54:02.52 |
+10:50:54.9 |
HIP 8904 |
8.89 |
| 2026-02-15 12:00 |
01:54:20.86 |
+10:51:48.4 |
HIP 8904 |
4.48 |
| 2026-02-16 00:00 |
01:54:39.31 |
+10:52:42.6 |
HIP 8904 |
1.85 |
| 2026-02-16 12:00 |
01:54:57.87 |
+10:53:37.5 |
HIP 8904 |
5.46 |
| 2026-02-17 00:00 |
01:55:16.55 |
+10:54:33.1 |
HIP 8904 |
10.00 |
| 2026-02-17 12:00 |
01:55:35.35 |
+10:55:29.4 |
HIP 8904 |
14.65 |
| 2026-02-18 00:00 |
01:55:54.25 |
+10:56:26.3 |
HIP 8904 |
19.37 |
| 2026-02-18 12:00 |
01:56:13.27 |
+10:57:23.9 |
HIP 8904 |
24.12 |
| 2026-02-19 00:00 |
01:56:32.40 |
+10:58:22.2 |
HIP 8904 |
28.90 |
| 2026-02-19 12:00 |
01:56:51.63 |
+10:59:21.1 |
HIP 9210 |
26.59 |
| 2026-02-20 00:00 |
01:57:10.98 |
+11:00:20.6 |
HIP 9210 |
22.96 |
| 2026-02-20 12:00 |
01:57:30.43 |
+11:01:20.7 |
HIP 9210 |
19.86 |
| 2026-02-21 00:00 |
01:57:49.98 |
+11:02:21.4 |
HIP 9210 |
17.57 |
| 2026-02-21 12:00 |
01:58:09.65 |
+11:03:22.7 |
HIP 9210 |
16.47 |
| 2026-02-22 00:00 |
01:58:29.41 |
+11:04:24.6 |
HIP 9210 |
16.83 |
| 2026-02-22 12:00 |
01:58:49.28 |
+11:05:27.1 |
HIP 9210 |
18.56 |
| 2026-02-23 00:00 |
01:59:09.25 |
+11:06:30.2 |
HIP 9210 |
21.37 |
| 2026-02-23 12:00 |
01:59:29.32 |
+11:07:33.8 |
HIP 9210 |
24.90 |
| 2026-02-24 00:00 |
01:59:49.49 |
+11:08:38.0 |
HIP 9210 |
28.91 |