C/2013 E1 (McNaught)
| Parameter |
Value |
| Designation |
C/2013 E1 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-06-12T02:48:47.306880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:31Z |
| Obs used |
172 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
8.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-06-11.0000000 |
| e |
1.00225843 |
| q (au) |
7.781630 |
| a (au) |
-3445.585444 |
| i (deg) |
158.720377 |
| Ω (om, deg) |
134.028821 |
| ω (w, deg) |
311.425764 |
| M (ma, deg) |
-0.000005 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.562 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.562 |
| n |
6.000 |
| gf |
0.996 |
| gb |
-0.823 |
| 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) |
| 2026-02-03 00:00 |
04:17:23.11 |
+40:58:40.5 |
HIP 20159 |
21.02 |
| 2026-02-03 12:00 |
04:17:19.71 |
+40:58:13.0 |
HIP 20159 |
21.70 |
| 2026-02-04 00:00 |
04:17:16.37 |
+40:57:45.5 |
HIP 20159 |
22.37 |
| 2026-02-04 12:00 |
04:17:13.08 |
+40:57:18.0 |
HIP 20159 |
23.05 |
| 2026-02-05 00:00 |
04:17:09.85 |
+40:56:50.6 |
HIP 20159 |
23.72 |
| 2026-02-05 12:00 |
04:17:06.67 |
+40:56:23.3 |
HIP 20159 |
24.38 |
| 2026-02-06 00:00 |
04:17:03.55 |
+40:55:55.9 |
HIP 20159 |
25.04 |
| 2026-02-06 12:00 |
04:17:00.48 |
+40:55:28.7 |
HIP 20159 |
25.69 |
| 2026-02-07 00:00 |
04:16:57.47 |
+40:55:01.4 |
HIP 20159 |
26.34 |
| 2026-02-07 12:00 |
04:16:54.51 |
+40:54:34.2 |
HIP 20159 |
26.98 |
| 2026-02-08 00:00 |
04:16:51.61 |
+40:54:07.1 |
HIP 20159 |
27.62 |
| 2026-02-08 12:00 |
04:16:48.76 |
+40:53:40.0 |
HIP 20159 |
28.25 |
| 2026-02-09 00:00 |
04:16:45.97 |
+40:53:13.0 |
HIP 20159 |
28.87 |
| 2026-02-09 12:00 |
04:16:43.23 |
+40:52:46.0 |
HIP 20159 |
29.48 |
| 2026-02-10 00:00 |
04:16:40.55 |
+40:52:19.0 |
HIP 20159 |
30.09 |
| 2026-02-10 12:00 |
04:16:37.93 |
+40:51:52.2 |
HIP 19811 |
30.26 |
| 2026-02-11 00:00 |
04:16:35.36 |
+40:51:25.4 |
HIP 19811 |
29.60 |
| 2026-02-11 12:00 |
04:16:32.85 |
+40:50:58.7 |
HIP 19811 |
28.95 |
| 2026-02-12 00:00 |
04:16:30.39 |
+40:50:32.0 |
HIP 19811 |
28.31 |
| 2026-02-12 12:00 |
04:16:27.99 |
+40:50:05.4 |
HIP 19811 |
27.68 |
| 2026-02-13 00:00 |
04:16:25.65 |
+40:49:38.9 |
HIP 19811 |
27.06 |
| 2026-02-13 12:00 |
04:16:23.36 |
+40:49:12.4 |
HIP 19811 |
26.44 |
| 2026-02-14 00:00 |
04:16:21.12 |
+40:48:46.1 |
HIP 19811 |
25.83 |
| 2026-02-14 12:00 |
04:16:18.95 |
+40:48:19.8 |
HIP 19811 |
25.23 |
| 2026-02-15 00:00 |
04:16:16.83 |
+40:47:53.6 |
HIP 19811 |
24.64 |
| 2026-02-15 12:00 |
04:16:14.76 |
+40:47:27.4 |
HIP 19811 |
24.05 |
| 2026-02-16 00:00 |
04:16:12.76 |
+40:47:01.4 |
HIP 19811 |
23.48 |
| 2026-02-16 12:00 |
04:16:10.80 |
+40:46:35.5 |
HIP 19811 |
22.91 |
| 2026-02-17 00:00 |
04:16:08.91 |
+40:46:09.6 |
HIP 19811 |
22.35 |
| 2026-02-17 12:00 |
04:16:07.07 |
+40:45:43.8 |
HIP 19811 |
21.79 |
| 2026-02-18 00:00 |
04:16:05.28 |
+40:45:18.2 |
HIP 19811 |
21.25 |
| 2026-02-18 12:00 |
04:16:03.56 |
+40:44:52.6 |
HIP 19811 |
20.71 |
| 2026-02-19 00:00 |
04:16:01.89 |
+40:44:27.1 |
HIP 19811 |
20.18 |
| 2026-02-19 12:00 |
04:16:00.27 |
+40:44:01.7 |
HIP 19811 |
19.66 |
| 2026-02-20 00:00 |
04:15:58.71 |
+40:43:36.5 |
HIP 19811 |
19.15 |
| 2026-02-20 12:00 |
04:15:57.21 |
+40:43:11.3 |
HIP 19811 |
18.65 |
| 2026-02-21 00:00 |
04:15:55.76 |
+40:42:46.2 |
HIP 19811 |
18.15 |
| 2026-02-21 12:00 |
04:15:54.37 |
+40:42:21.3 |
HIP 19811 |
17.67 |
| 2026-02-22 00:00 |
04:15:53.03 |
+40:41:56.4 |
HIP 19811 |
17.19 |
| 2026-02-22 12:00 |
04:15:51.75 |
+40:41:31.7 |
HIP 19811 |
16.72 |
| 2026-02-23 00:00 |
04:15:50.52 |
+40:41:07.1 |
HIP 19811 |
16.26 |
| 2026-02-23 12:00 |
04:15:49.35 |
+40:40:42.6 |
HIP 19811 |
15.81 |
| 2026-02-24 00:00 |
04:15:48.24 |
+40:40:18.2 |
HIP 19811 |
15.36 |