| Parameter |
Value |
| Designation |
C/2006 XA1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-07-21T21:31:41.396160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:03Z |
| Obs used |
486 |
| NEO |
- |
| M1 |
7.400 |
| K1 |
17.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2007-03-16.0000000 |
| e |
0.99283774 |
| q (au) |
1.804376 |
| a (au) |
251.928275 |
| i (deg) |
30.629404 |
| Ω (om, deg) |
318.663524 |
| ω (w, deg) |
187.418049 |
| M (ma, deg) |
359.968475 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.115 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.115 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.883 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
20:29:25.14 |
-27:51:02.4 |
HIP 100923 |
23.71 |
| 2026-09-20 12:00 |
20:29:23.19 |
-27:51:01.7 |
HIP 100923 |
23.29 |
| 2026-09-21 00:00 |
20:29:21.26 |
-27:51:00.9 |
HIP 100923 |
22.88 |
| 2026-09-21 12:00 |
20:29:19.36 |
-27:51:00.0 |
HIP 100923 |
22.47 |
| 2026-09-22 00:00 |
20:29:17.48 |
-27:50:58.9 |
HIP 100923 |
22.07 |
| 2026-09-22 12:00 |
20:29:15.63 |
-27:50:57.7 |
HIP 100923 |
21.67 |
| 2026-09-23 00:00 |
20:29:13.80 |
-27:50:56.4 |
HIP 100923 |
21.27 |
| 2026-09-23 12:00 |
20:29:12.00 |
-27:50:55.0 |
HIP 100923 |
20.89 |
| 2026-09-24 00:00 |
20:29:10.22 |
-27:50:53.5 |
HIP 100923 |
20.50 |
| 2026-09-24 12:00 |
20:29:08.47 |
-27:50:51.9 |
HIP 100923 |
20.13 |
| 2026-09-25 00:00 |
20:29:06.75 |
-27:50:50.1 |
HIP 100923 |
19.75 |
| 2026-09-25 12:00 |
20:29:05.05 |
-27:50:48.3 |
HIP 100923 |
19.39 |
| 2026-09-26 00:00 |
20:29:03.37 |
-27:50:46.3 |
HIP 100923 |
19.02 |
| 2026-09-26 12:00 |
20:29:01.72 |
-27:50:44.2 |
HIP 100923 |
18.67 |
| 2026-09-27 00:00 |
20:29:00.10 |
-27:50:42.0 |
HIP 100923 |
18.32 |
| 2026-09-27 12:00 |
20:28:58.50 |
-27:50:39.7 |
HIP 100923 |
17.97 |
| 2026-09-28 00:00 |
20:28:56.93 |
-27:50:37.3 |
HIP 100923 |
17.63 |
| 2026-09-28 12:00 |
20:28:55.39 |
-27:50:34.7 |
HIP 100923 |
17.29 |
| 2026-09-29 00:00 |
20:28:53.87 |
-27:50:32.0 |
HIP 100923 |
16.96 |
| 2026-09-29 12:00 |
20:28:52.38 |
-27:50:29.3 |
HIP 100923 |
16.64 |
| 2026-09-30 00:00 |
20:28:50.91 |
-27:50:26.4 |
HIP 100923 |
16.32 |
| 2026-09-30 12:00 |
20:28:49.47 |
-27:50:23.4 |
HIP 100923 |
16.00 |
| 2026-10-01 00:00 |
20:28:48.06 |
-27:50:20.3 |
HIP 100923 |
15.69 |
| 2026-10-01 12:00 |
20:28:46.68 |
-27:50:17.0 |
HIP 100923 |
15.39 |
| 2026-10-02 00:00 |
20:28:45.32 |
-27:50:13.7 |
HIP 100923 |
15.09 |
| 2026-10-02 12:00 |
20:28:43.99 |
-27:50:10.2 |
HIP 100923 |
14.79 |
| 2026-10-03 00:00 |
20:28:42.69 |
-27:50:06.7 |
HIP 100923 |
14.50 |
| 2026-10-03 12:00 |
20:28:41.41 |
-27:50:03.0 |
HIP 100923 |
14.22 |
| 2026-10-04 00:00 |
20:28:40.17 |
-27:49:59.2 |
HIP 100923 |
13.94 |
| 2026-10-04 12:00 |
20:28:38.95 |
-27:49:55.3 |
HIP 100923 |
13.66 |
| 2026-10-05 00:00 |
20:28:37.76 |
-27:49:51.3 |
HIP 100923 |
13.40 |
| 2026-10-05 12:00 |
20:28:36.59 |
-27:49:47.2 |
HIP 100923 |
13.13 |
| 2026-10-06 00:00 |
20:28:35.46 |
-27:49:42.9 |
HIP 100923 |
12.87 |
| 2026-10-06 12:00 |
20:28:34.35 |
-27:49:38.6 |
HIP 100923 |
12.62 |
| 2026-10-07 00:00 |
20:28:33.27 |
-27:49:34.1 |
HIP 100923 |
12.37 |
| 2026-10-07 12:00 |
20:28:32.22 |
-27:49:29.5 |
HIP 100923 |
12.13 |
| 2026-10-08 00:00 |
20:28:31.20 |
-27:49:24.9 |
HIP 100923 |
11.89 |
| 2026-10-08 12:00 |
20:28:30.20 |
-27:49:20.1 |
HIP 100923 |
11.65 |
| 2026-10-09 00:00 |
20:28:29.24 |
-27:49:15.2 |
HIP 100923 |
11.43 |
| 2026-10-09 12:00 |
20:28:28.30 |
-27:49:10.1 |
HIP 100923 |
11.20 |
| 2026-10-10 00:00 |
20:28:27.39 |
-27:49:05.0 |
HIP 100923 |
10.98 |
| 2026-10-10 12:00 |
20:28:26.52 |
-27:48:59.8 |
HIP 100923 |
10.77 |
| 2026-10-11 00:00 |
20:28:25.67 |
-27:48:54.4 |
HIP 100923 |
10.56 |