| Parameter |
Value |
| Designation |
C/2001 A1 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2000-09-17T14:53:00.830400Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:08Z |
| Obs used |
126 |
| NEO |
- |
| M1 |
12.800 |
| K1 |
6.750 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2001-02-04.0000000 |
| e |
0.99093655 |
| q (au) |
2.406447 |
| a (au) |
265.511207 |
| i (deg) |
59.940739 |
| Ω (om, deg) |
339.594496 |
| ω (w, deg) |
107.889040 |
| M (ma, deg) |
0.031753 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.703 + 3.720\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.703 |
| n |
3.720 |
| gf |
1.000 |
| gb |
-0.555 |
| 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) |
| 2026-06-01 00:00 |
12:19:53.95 |
-73:08:55.4 |
HIP 60487 |
18.09 |
| 2026-06-01 12:00 |
12:19:50.63 |
-73:08:21.8 |
HIP 60487 |
18.31 |
| 2026-06-02 00:00 |
12:19:47.38 |
-73:07:48.2 |
HIP 60487 |
18.53 |
| 2026-06-02 12:00 |
12:19:44.19 |
-73:07:14.4 |
HIP 60487 |
18.77 |
| 2026-06-03 00:00 |
12:19:41.07 |
-73:06:40.6 |
HIP 60232 |
18.77 |
| 2026-06-03 12:00 |
12:19:38.02 |
-73:06:06.6 |
HIP 60232 |
18.31 |
| 2026-06-04 00:00 |
12:19:35.04 |
-73:05:32.6 |
HIP 60232 |
17.86 |
| 2026-06-04 12:00 |
12:19:32.12 |
-73:04:58.5 |
HIP 60232 |
17.41 |
| 2026-06-05 00:00 |
12:19:29.27 |
-73:04:24.4 |
HIP 60232 |
16.97 |
| 2026-06-05 12:00 |
12:19:26.49 |
-73:03:50.1 |
HIP 60232 |
16.54 |
| 2026-06-06 00:00 |
12:19:23.77 |
-73:03:15.8 |
HIP 60232 |
16.12 |
| 2026-06-06 12:00 |
12:19:21.13 |
-73:02:41.5 |
HIP 60232 |
15.71 |
| 2026-06-07 00:00 |
12:19:18.55 |
-73:02:07.0 |
HIP 60232 |
15.30 |
| 2026-06-07 12:00 |
12:19:16.04 |
-73:01:32.5 |
HIP 60232 |
14.91 |
| 2026-06-08 00:00 |
12:19:13.59 |
-73:00:58.0 |
HIP 60232 |
14.52 |
| 2026-06-08 12:00 |
12:19:11.22 |
-73:00:23.4 |
HIP 60232 |
14.15 |
| 2026-06-09 00:00 |
12:19:08.91 |
-72:59:48.7 |
HIP 60232 |
13.79 |
| 2026-06-09 12:00 |
12:19:06.67 |
-72:59:14.0 |
HIP 60232 |
13.44 |
| 2026-06-10 00:00 |
12:19:04.50 |
-72:58:39.2 |
HIP 60232 |
13.11 |
| 2026-06-10 12:00 |
12:19:02.40 |
-72:58:04.4 |
HIP 60232 |
12.80 |
| 2026-06-11 00:00 |
12:19:00.37 |
-72:57:29.6 |
HIP 60232 |
12.50 |
| 2026-06-11 12:00 |
12:18:58.40 |
-72:56:54.7 |
HIP 60232 |
12.22 |
| 2026-06-12 00:00 |
12:18:56.51 |
-72:56:19.8 |
HIP 60232 |
11.96 |
| 2026-06-12 12:00 |
12:18:54.68 |
-72:55:44.8 |
HIP 60232 |
11.71 |
| 2026-06-13 00:00 |
12:18:52.92 |
-72:55:09.8 |
HIP 60232 |
11.50 |
| 2026-06-13 12:00 |
12:18:51.23 |
-72:54:34.8 |
HIP 60232 |
11.30 |
| 2026-06-14 00:00 |
12:18:49.61 |
-72:53:59.8 |
HIP 60232 |
11.13 |
| 2026-06-14 12:00 |
12:18:48.06 |
-72:53:24.7 |
HIP 60232 |
10.98 |
| 2026-06-15 00:00 |
12:18:46.58 |
-72:52:49.6 |
HIP 60232 |
10.86 |
| 2026-06-15 12:00 |
12:18:45.16 |
-72:52:14.5 |
HIP 60232 |
10.76 |
| 2026-06-16 00:00 |
12:18:43.82 |
-72:51:39.4 |
HIP 60232 |
10.69 |
| 2026-06-16 12:00 |
12:18:42.54 |
-72:51:04.3 |
HIP 60232 |
10.65 |
| 2026-06-17 00:00 |
12:18:41.34 |
-72:50:29.2 |
HIP 60232 |
10.64 |
| 2026-06-17 12:00 |
12:18:40.20 |
-72:49:54.1 |
HIP 60232 |
10.66 |
| 2026-06-18 00:00 |
12:18:39.13 |
-72:49:19.0 |
HIP 60232 |
10.70 |
| 2026-06-18 12:00 |
12:18:38.13 |
-72:48:43.8 |
HIP 60232 |
10.77 |
| 2026-06-19 00:00 |
12:18:37.20 |
-72:48:08.7 |
HIP 60232 |
10.87 |
| 2026-06-19 12:00 |
12:18:36.33 |
-72:47:33.6 |
HIP 60232 |
10.99 |
| 2026-06-20 00:00 |
12:18:35.54 |
-72:46:58.5 |
HIP 60232 |
11.14 |
| 2026-06-20 12:00 |
12:18:34.81 |
-72:46:23.4 |
HIP 60232 |
11.31 |
| 2026-06-21 00:00 |
12:18:34.15 |
-72:45:48.4 |
HIP 60232 |
11.51 |
| 2026-06-21 12:00 |
12:18:33.56 |
-72:45:13.3 |
HIP 60232 |
11.72 |
| 2026-06-22 00:00 |
12:18:33.04 |
-72:44:38.3 |
HIP 60232 |
11.96 |