126P/IRAS
| Parameter |
Value |
| Designation |
126P/IRAS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2023-07-05T08:31:56.219520Z |
| Orbit solution date (soln_date, UTC) |
2025-10-30T09:34:36Z |
| Obs used |
1717 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
11.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-05-27.0000000 |
| e |
0.69627539 |
| q (au) |
1.713008 |
| a (au) |
5.640004 |
| i (deg) |
45.869371 |
| Ω (om, deg) |
357.862226 |
| ω (w, deg) |
356.523683 |
| M (ma, deg) |
303.387535 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.785 + 5.260\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.785 |
| n |
5.260 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.992 |
| 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 |
11:10:30.63 |
+38:15:55.1 |
HIP 54591 |
24.16 |
| 2026-02-03 12:00 |
11:10:12.91 |
+38:17:35.2 |
HIP 54591 |
22.43 |
| 2026-02-04 00:00 |
11:09:55.08 |
+38:19:14.4 |
HIP 54426 |
20.77 |
| 2026-02-04 12:00 |
11:09:37.11 |
+38:20:52.6 |
HIP 54426 |
16.92 |
| 2026-02-05 00:00 |
11:09:19.03 |
+38:22:30.0 |
HIP 54426 |
13.08 |
| 2026-02-05 12:00 |
11:09:00.83 |
+38:24:06.4 |
HIP 54426 |
9.26 |
| 2026-02-06 00:00 |
11:08:42.51 |
+38:25:41.8 |
HIP 54426 |
5.55 |
| 2026-02-06 12:00 |
11:08:24.08 |
+38:27:16.2 |
HIP 54426 |
2.56 |
| 2026-02-07 00:00 |
11:08:05.53 |
+38:28:49.6 |
HIP 54426 |
3.65 |
| 2026-02-07 12:00 |
11:07:46.88 |
+38:30:22.0 |
HIP 54426 |
7.17 |
| 2026-02-08 00:00 |
11:07:28.12 |
+38:31:53.3 |
HIP 54426 |
11.00 |
| 2026-02-08 12:00 |
11:07:09.25 |
+38:33:23.6 |
HIP 54426 |
14.91 |
| 2026-02-09 00:00 |
11:06:50.27 |
+38:34:52.8 |
HIP 54235 |
16.50 |
| 2026-02-09 12:00 |
11:06:31.20 |
+38:36:20.8 |
HIP 54235 |
15.20 |
| 2026-02-10 00:00 |
11:06:12.03 |
+38:37:47.8 |
HIP 54235 |
14.87 |
| 2026-02-10 12:00 |
11:05:52.76 |
+38:39:13.6 |
HIP 54235 |
15.59 |
| 2026-02-11 00:00 |
11:05:33.40 |
+38:40:38.3 |
HIP 54235 |
17.23 |
| 2026-02-11 12:00 |
11:05:13.95 |
+38:42:01.8 |
HIP 54107 |
14.81 |
| 2026-02-12 00:00 |
11:04:54.41 |
+38:43:24.0 |
HIP 54107 |
11.19 |
| 2026-02-12 12:00 |
11:04:34.78 |
+38:44:45.1 |
HIP 54107 |
8.02 |
| 2026-02-13 00:00 |
11:04:15.07 |
+38:46:05.0 |
HIP 54107 |
6.04 |
| 2026-02-13 12:00 |
11:03:55.28 |
+38:47:23.6 |
HIP 54107 |
6.49 |
| 2026-02-14 00:00 |
11:03:35.41 |
+38:48:40.9 |
HIP 54107 |
9.01 |
| 2026-02-14 12:00 |
11:03:15.47 |
+38:49:57.0 |
HIP 54073 |
10.61 |
| 2026-02-15 00:00 |
11:02:55.45 |
+38:51:11.8 |
HIP 54073 |
12.92 |
| 2026-02-15 12:00 |
11:02:35.37 |
+38:52:25.2 |
HIP 54073 |
15.98 |
| 2026-02-16 00:00 |
11:02:15.21 |
+38:53:37.3 |
HIP 54073 |
19.44 |
| 2026-02-16 12:00 |
11:01:55.00 |
+38:54:48.1 |
HIP 53838 |
21.87 |
| 2026-02-17 00:00 |
11:01:34.72 |
+38:55:57.6 |
HIP 53838 |
18.84 |
| 2026-02-17 12:00 |
11:01:14.38 |
+38:57:05.6 |
HIP 53838 |
16.31 |
| 2026-02-18 00:00 |
11:00:53.98 |
+38:58:12.3 |
HIP 53838 |
14.54 |
| 2026-02-18 12:00 |
11:00:33.54 |
+38:59:17.6 |
HIP 53838 |
13.83 |
| 2026-02-19 00:00 |
11:00:13.04 |
+39:00:21.5 |
HIP 53838 |
14.34 |
| 2026-02-19 12:00 |
10:59:52.50 |
+39:01:23.9 |
HIP 53838 |
15.96 |
| 2026-02-20 00:00 |
10:59:31.91 |
+39:02:24.9 |
HIP 53620 |
15.47 |
| 2026-02-20 12:00 |
10:59:11.28 |
+39:03:24.4 |
HIP 53620 |
11.45 |
| 2026-02-21 00:00 |
10:58:50.61 |
+39:04:22.5 |
HIP 53620 |
7.53 |
| 2026-02-21 12:00 |
10:58:29.91 |
+39:05:19.1 |
HIP 53620 |
4.05 |
| 2026-02-22 00:00 |
10:58:09.18 |
+39:06:14.2 |
HIP 53620 |
3.17 |
| 2026-02-22 12:00 |
10:57:48.41 |
+39:07:07.8 |
HIP 53620 |
6.13 |
| 2026-02-23 00:00 |
10:57:27.62 |
+39:08:00.0 |
HIP 53620 |
9.95 |
| 2026-02-23 12:00 |
10:57:06.81 |
+39:08:50.5 |
HIP 53620 |
13.94 |
| 2026-02-24 00:00 |
10:56:45.98 |
+39:09:39.6 |
HIP 53620 |
17.98 |