| Parameter |
Value |
| Designation |
C/2012 L2 (LINEAR) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-05-09T08:04:55.027200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:14Z |
| Obs used |
2119 |
| NEO |
- |
| M1 |
11.300 |
| K1 |
6.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-12-18.0000000 |
| e |
0.99733350 |
| q (au) |
1.508545 |
| a (au) |
565.739557 |
| i (deg) |
70.980594 |
| Ω (om, deg) |
270.302116 |
| ω (w, deg) |
205.786395 |
| M (ma, deg) |
359.989575 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.171 + 4.614\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.171 |
| n |
4.614 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.874 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2003-04-13 |
2012-06-17 |
-24.5614 |
+15.420 |
| 2012-06-17 |
2012-12-17 |
-0.8759 |
+0.427 |
| 2012-12-17 |
2013-05-09 |
+6.2793 |
-2.140 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
18:04:30.39 |
-23:23:40.3 |
HIP 88631 |
18.99 |
| 2026-06-01 12:00 |
18:04:26.31 |
-23:23:37.3 |
HIP 88631 |
19.87 |
| 2026-06-02 00:00 |
18:04:22.22 |
-23:23:34.3 |
HIP 88631 |
20.77 |
| 2026-06-02 12:00 |
18:04:18.12 |
-23:23:31.2 |
HIP 88631 |
21.66 |
| 2026-06-03 00:00 |
18:04:14.00 |
-23:23:28.2 |
HIP 88631 |
22.57 |
| 2026-06-03 12:00 |
18:04:09.87 |
-23:23:25.1 |
HIP 88631 |
23.48 |
| 2026-06-04 00:00 |
18:04:05.73 |
-23:23:22.1 |
HIP 88631 |
24.40 |
| 2026-06-04 12:00 |
18:04:01.58 |
-23:23:19.0 |
HIP 88631 |
25.32 |
| 2026-06-05 00:00 |
18:03:57.42 |
-23:23:15.9 |
HIP 88631 |
26.24 |
| 2026-06-05 12:00 |
18:03:53.25 |
-23:23:12.8 |
HIP 88631 |
27.17 |
| 2026-06-06 00:00 |
18:03:49.06 |
-23:23:09.8 |
HIP 88631 |
28.11 |
| 2026-06-06 12:00 |
18:03:44.86 |
-23:23:06.7 |
HIP 88330 |
28.25 |
| 2026-06-07 00:00 |
18:03:40.66 |
-23:23:03.6 |
HIP 88330 |
27.58 |
| 2026-06-07 12:00 |
18:03:36.44 |
-23:23:00.5 |
HIP 88330 |
26.92 |
| 2026-06-08 00:00 |
18:03:32.22 |
-23:22:57.4 |
HIP 88330 |
26.29 |
| 2026-06-08 12:00 |
18:03:27.98 |
-23:22:54.3 |
HIP 88330 |
25.67 |
| 2026-06-09 00:00 |
18:03:23.74 |
-23:22:51.1 |
HIP 88330 |
25.07 |
| 2026-06-09 12:00 |
18:03:19.49 |
-23:22:48.0 |
HIP 88330 |
24.50 |
| 2026-06-10 00:00 |
18:03:15.23 |
-23:22:44.9 |
HIP 88330 |
23.95 |
| 2026-06-10 12:00 |
18:03:10.96 |
-23:22:41.7 |
HIP 88330 |
23.43 |
| 2026-06-11 00:00 |
18:03:06.69 |
-23:22:38.6 |
HIP 88330 |
22.94 |
| 2026-06-11 12:00 |
18:03:02.40 |
-23:22:35.5 |
HIP 88330 |
22.48 |
| 2026-06-12 00:00 |
18:02:58.11 |
-23:22:32.3 |
HIP 88330 |
22.05 |
| 2026-06-12 12:00 |
18:02:53.82 |
-23:22:29.1 |
HIP 88330 |
21.66 |
| 2026-06-13 00:00 |
18:02:49.52 |
-23:22:26.0 |
HIP 88330 |
21.31 |
| 2026-06-13 12:00 |
18:02:45.21 |
-23:22:22.8 |
HIP 88330 |
21.00 |
| 2026-06-14 00:00 |
18:02:40.89 |
-23:22:19.6 |
HIP 88330 |
20.73 |
| 2026-06-14 12:00 |
18:02:36.58 |
-23:22:16.5 |
HIP 88330 |
20.51 |
| 2026-06-15 00:00 |
18:02:32.25 |
-23:22:13.3 |
HIP 88330 |
20.33 |
| 2026-06-15 12:00 |
18:02:27.93 |
-23:22:10.1 |
HIP 88330 |
20.20 |
| 2026-06-16 00:00 |
18:02:23.60 |
-23:22:06.9 |
HIP 88330 |
20.11 |
| 2026-06-16 12:00 |
18:02:19.26 |
-23:22:03.7 |
HIP 88330 |
20.08 |
| 2026-06-17 00:00 |
18:02:14.92 |
-23:22:00.4 |
HIP 88330 |
20.10 |
| 2026-06-17 12:00 |
18:02:10.58 |
-23:21:57.2 |
HIP 88330 |
20.16 |
| 2026-06-18 00:00 |
18:02:06.24 |
-23:21:54.0 |
HIP 88330 |
20.27 |
| 2026-06-18 12:00 |
18:02:01.90 |
-23:21:50.8 |
HIP 88330 |
20.44 |
| 2026-06-19 00:00 |
18:01:57.55 |
-23:21:47.5 |
HIP 88330 |
20.65 |
| 2026-06-19 12:00 |
18:01:53.20 |
-23:21:44.3 |
HIP 88330 |
20.90 |
| 2026-06-20 00:00 |
18:01:48.86 |
-23:21:41.0 |
HIP 88330 |
21.20 |
| 2026-06-20 12:00 |
18:01:44.51 |
-23:21:37.8 |
HIP 88330 |
21.54 |
| 2026-06-21 00:00 |
18:01:40.16 |
-23:21:34.5 |
HIP 88330 |
21.93 |
| 2026-06-21 12:00 |
18:01:35.81 |
-23:21:31.2 |
HIP 88330 |
22.35 |
| 2026-06-22 00:00 |
18:01:31.46 |
-23:21:28.0 |
HIP 88330 |
22.80 |