| 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) |
| 2026-07-29 00:00 |
12:20:51.55 |
-72:05:19.9 |
HIP 60082 |
12.77 |
| 2026-07-29 12:00 |
12:20:55.61 |
-72:04:53.4 |
HIP 60082 |
12.60 |
| 2026-07-30 00:00 |
12:20:59.71 |
-72:04:27.1 |
HIP 60082 |
12.47 |
| 2026-07-30 12:00 |
12:21:03.88 |
-72:04:00.9 |
HIP 60082 |
12.36 |
| 2026-07-31 00:00 |
12:21:08.09 |
-72:03:34.9 |
HIP 60082 |
12.29 |
| 2026-07-31 12:00 |
12:21:12.35 |
-72:03:09.2 |
HIP 60082 |
12.24 |
| 2026-08-01 00:00 |
12:21:16.66 |
-72:02:43.6 |
HIP 60082 |
12.21 |
| 2026-08-01 12:00 |
12:21:21.02 |
-72:02:18.3 |
HIP 60082 |
12.22 |
| 2026-08-02 00:00 |
12:21:25.43 |
-72:01:53.1 |
HIP 60082 |
12.26 |
| 2026-08-02 12:00 |
12:21:29.89 |
-72:01:28.1 |
HIP 60082 |
12.33 |
| 2026-08-03 00:00 |
12:21:34.40 |
-72:01:03.4 |
HIP 60082 |
12.42 |
| 2026-08-03 12:00 |
12:21:38.96 |
-72:00:38.9 |
HIP 60082 |
12.55 |
| 2026-08-04 00:00 |
12:21:43.56 |
-72:00:14.5 |
HIP 60082 |
12.69 |
| 2026-08-04 12:00 |
12:21:48.21 |
-71:59:50.4 |
HIP 60082 |
12.87 |
| 2026-08-05 00:00 |
12:21:52.91 |
-71:59:26.5 |
HIP 60082 |
13.07 |
| 2026-08-05 12:00 |
12:21:57.66 |
-71:59:02.8 |
HIP 60082 |
13.29 |
| 2026-08-06 00:00 |
12:22:02.46 |
-71:58:39.3 |
HIP 60082 |
13.54 |
| 2026-08-06 12:00 |
12:22:07.30 |
-71:58:16.0 |
HIP 60082 |
13.81 |
| 2026-08-07 00:00 |
12:22:12.19 |
-71:57:53.0 |
HIP 60082 |
14.10 |
| 2026-08-07 12:00 |
12:22:17.12 |
-71:57:30.2 |
HIP 60082 |
14.40 |
| 2026-08-08 00:00 |
12:22:22.10 |
-71:57:07.6 |
HIP 60082 |
14.73 |
| 2026-08-08 12:00 |
12:22:27.13 |
-71:56:45.2 |
HIP 60082 |
15.07 |
| 2026-08-09 00:00 |
12:22:32.20 |
-71:56:23.0 |
HIP 60082 |
15.42 |
| 2026-08-09 12:00 |
12:22:37.31 |
-71:56:01.1 |
HIP 60082 |
15.79 |
| 2026-08-10 00:00 |
12:22:42.47 |
-71:55:39.4 |
HIP 60082 |
16.18 |
| 2026-08-10 12:00 |
12:22:47.68 |
-71:55:17.9 |
HIP 60082 |
16.57 |
| 2026-08-11 00:00 |
12:22:52.93 |
-71:54:56.7 |
HIP 60082 |
16.98 |
| 2026-08-11 12:00 |
12:22:58.22 |
-71:54:35.7 |
HIP 60082 |
17.40 |
| 2026-08-12 00:00 |
12:23:03.55 |
-71:54:14.9 |
HIP 60082 |
17.83 |
| 2026-08-12 12:00 |
12:23:08.93 |
-71:53:54.4 |
HIP 60082 |
18.27 |
| 2026-08-13 00:00 |
12:23:14.35 |
-71:53:34.1 |
HIP 60082 |
18.71 |
| 2026-08-13 12:00 |
12:23:19.81 |
-71:53:14.0 |
HIP 60082 |
19.17 |
| 2026-08-14 00:00 |
12:23:25.32 |
-71:52:54.2 |
HIP 60082 |
19.63 |
| 2026-08-14 12:00 |
12:23:30.86 |
-71:52:34.6 |
HIP 60082 |
20.10 |
| 2026-08-15 00:00 |
12:23:36.44 |
-71:52:15.3 |
HIP 60082 |
20.57 |
| 2026-08-15 12:00 |
12:23:42.07 |
-71:51:56.2 |
HIP 60763 |
20.72 |
| 2026-08-16 00:00 |
12:23:47.74 |
-71:51:37.4 |
HIP 60763 |
20.18 |
| 2026-08-16 12:00 |
12:23:53.44 |
-71:51:18.8 |
HIP 60763 |
19.64 |
| 2026-08-17 00:00 |
12:23:59.18 |
-71:51:00.5 |
HIP 60763 |
19.10 |
| 2026-08-17 12:00 |
12:24:04.97 |
-71:50:42.4 |
HIP 60763 |
18.55 |
| 2026-08-18 00:00 |
12:24:10.79 |
-71:50:24.5 |
HIP 60763 |
18.01 |
| 2026-08-18 12:00 |
12:24:16.65 |
-71:50:06.9 |
HIP 60763 |
17.47 |
| 2026-08-19 00:00 |
12:24:22.54 |
-71:49:49.6 |
HIP 60763 |
16.93 |