| Parameter |
Value |
| Designation |
C/2013 G6 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-07-25T05:28:45.828480Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:34Z |
| Obs used |
230 |
| NEO |
- |
| M1 |
7.100 |
| K1 |
27.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-06-18.0000000 |
| e |
0.99470498 |
| q (au) |
2.048499 |
| a (au) |
386.872597 |
| i (deg) |
124.084326 |
| Ω (om, deg) |
44.567402 |
| ω (w, deg) |
215.692475 |
| M (ma, deg) |
359.995178 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.902 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.902 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.985 |
| k |
1.000 |
| 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 |
| 2013-04-13 |
2013-07-08 |
+39.8436 |
-14.073 |
| 2013-08-03 |
2014-02-05 |
+22.5987 |
-10.706 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
02:27:01.22 |
+18:53:50.1 |
HIP 11355 |
11.15 |
| 2026-03-26 12:00 |
02:27:04.33 |
+18:54:06.0 |
HIP 11355 |
11.88 |
| 2026-03-27 00:00 |
02:27:07.46 |
+18:54:22.1 |
HIP 11355 |
12.62 |
| 2026-03-27 12:00 |
02:27:10.62 |
+18:54:38.3 |
HIP 11355 |
13.37 |
| 2026-03-28 00:00 |
02:27:13.78 |
+18:54:54.7 |
HIP 11355 |
14.13 |
| 2026-03-28 12:00 |
02:27:16.97 |
+18:55:11.1 |
HIP 11355 |
14.89 |
| 2026-03-29 00:00 |
02:27:20.17 |
+18:55:27.6 |
HIP 11355 |
15.67 |
| 2026-03-29 12:00 |
02:27:23.39 |
+18:55:44.3 |
HIP 11355 |
16.45 |
| 2026-03-30 00:00 |
02:27:26.63 |
+18:56:01.0 |
HIP 11355 |
17.24 |
| 2026-03-30 12:00 |
02:27:29.88 |
+18:56:17.9 |
HIP 11355 |
18.03 |
| 2026-03-31 00:00 |
02:27:33.15 |
+18:56:34.8 |
HIP 11355 |
18.83 |
| 2026-03-31 12:00 |
02:27:36.43 |
+18:56:51.9 |
HIP 11355 |
19.63 |
| 2026-04-01 00:00 |
02:27:39.73 |
+18:57:09.1 |
HIP 11355 |
20.45 |
| 2026-04-01 12:00 |
02:27:43.04 |
+18:57:26.3 |
HIP 11355 |
21.26 |
| 2026-04-02 00:00 |
02:27:46.37 |
+18:57:43.7 |
HIP 11355 |
22.08 |
| 2026-04-02 12:00 |
02:27:49.71 |
+18:58:01.2 |
HIP 11355 |
22.91 |
| 2026-04-03 00:00 |
02:27:53.07 |
+18:58:18.7 |
HIP 11355 |
23.74 |
| 2026-04-03 12:00 |
02:27:56.44 |
+18:58:36.4 |
HIP 11355 |
24.58 |
| 2026-04-04 00:00 |
02:27:59.83 |
+18:58:54.1 |
HIP 11539 |
24.98 |
| 2026-04-04 12:00 |
02:28:03.23 |
+18:59:12.0 |
HIP 11539 |
24.37 |
| 2026-04-05 00:00 |
02:28:06.64 |
+18:59:30.0 |
HIP 11539 |
23.78 |
| 2026-04-05 12:00 |
02:28:10.07 |
+18:59:48.0 |
HIP 11539 |
23.20 |
| 2026-04-06 00:00 |
02:28:13.51 |
+19:00:06.1 |
HIP 11539 |
22.64 |
| 2026-04-06 12:00 |
02:28:16.96 |
+19:00:24.4 |
HIP 11539 |
22.09 |
| 2026-04-07 00:00 |
02:28:20.42 |
+19:00:42.7 |
HIP 11539 |
21.56 |
| 2026-04-07 12:00 |
02:28:23.90 |
+19:01:01.1 |
HIP 11539 |
21.06 |
| 2026-04-08 00:00 |
02:28:27.39 |
+19:01:19.6 |
HIP 11539 |
20.57 |
| 2026-04-08 12:00 |
02:28:30.89 |
+19:01:38.2 |
HIP 11539 |
20.11 |
| 2026-04-09 00:00 |
02:28:34.40 |
+19:01:56.8 |
HIP 11539 |
19.68 |
| 2026-04-09 12:00 |
02:28:37.93 |
+19:02:15.6 |
HIP 11539 |
19.28 |
| 2026-04-10 00:00 |
02:28:41.46 |
+19:02:34.4 |
HIP 11539 |
18.91 |
| 2026-04-10 12:00 |
02:28:45.01 |
+19:02:53.3 |
HIP 11539 |
18.57 |
| 2026-04-11 00:00 |
02:28:48.57 |
+19:03:12.3 |
HIP 11539 |
18.27 |
| 2026-04-11 12:00 |
02:28:52.13 |
+19:03:31.4 |
HIP 11539 |
18.01 |
| 2026-04-12 00:00 |
02:28:55.71 |
+19:03:50.5 |
HIP 11539 |
17.79 |
| 2026-04-12 12:00 |
02:28:59.29 |
+19:04:09.8 |
HIP 11539 |
17.61 |
| 2026-04-13 00:00 |
02:29:02.89 |
+19:04:29.1 |
HIP 11539 |
17.48 |
| 2026-04-13 12:00 |
02:29:06.50 |
+19:04:48.5 |
HIP 11539 |
17.39 |
| 2026-04-14 00:00 |
02:29:10.11 |
+19:05:07.9 |
HIP 11539 |
17.35 |
| 2026-04-14 12:00 |
02:29:13.73 |
+19:05:27.5 |
HIP 11539 |
17.36 |
| 2026-04-15 00:00 |
02:29:17.36 |
+19:05:47.1 |
HIP 11539 |
17.41 |
| 2026-04-15 12:00 |
02:29:21.00 |
+19:06:06.7 |
HIP 11539 |
17.52 |
| 2026-04-16 00:00 |
02:29:24.65 |
+19:06:26.5 |
HIP 11539 |
17.67 |