| Parameter |
Value |
| Designation |
P/2014 X1 (Elenin) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-01-07T17:47:02.451840Z |
| Orbit solution date (soln_date, UTC) |
2024-10-10T18:10:33Z |
| Obs used |
630 |
| NEO |
- |
| M1 |
15.500 |
| K1 |
6.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-01-31.0000000 |
| e |
0.71002420 |
| q (au) |
1.814883 |
| a (au) |
6.258740 |
| i (deg) |
25.971382 |
| Ω (om, deg) |
61.569156 |
| ω (w, deg) |
34.367877 |
| M (ma, deg) |
1.464080 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.535 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.535 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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 |
| 2014-09-04 |
2015-01-06 |
+19.0602 |
-4.445 |
| 2015-01-08 |
2016-03-15 |
+3.0066 |
-1.877 |
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 |
20:33:23.77 |
-39:53:43.2 |
HIP 101466 |
17.90 |
| 2026-03-26 12:00 |
20:33:35.57 |
-39:54:15.9 |
HIP 101466 |
18.02 |
| 2026-03-27 00:00 |
20:33:47.28 |
-39:54:49.3 |
HIP 101466 |
18.44 |
| 2026-03-27 12:00 |
20:33:58.89 |
-39:55:23.3 |
HIP 101466 |
19.14 |
| 2026-03-28 00:00 |
20:34:10.40 |
-39:55:57.9 |
HIP 101466 |
20.09 |
| 2026-03-28 12:00 |
20:34:21.82 |
-39:56:33.1 |
HIP 101466 |
21.25 |
| 2026-03-29 00:00 |
20:34:33.15 |
-39:57:09.0 |
HIP 101625 |
21.72 |
| 2026-03-29 12:00 |
20:34:44.37 |
-39:57:45.4 |
HIP 101591 |
20.50 |
| 2026-03-30 00:00 |
20:34:55.50 |
-39:58:22.4 |
HIP 101591 |
19.29 |
| 2026-03-30 12:00 |
20:35:06.52 |
-39:59:00.1 |
HIP 101591 |
18.27 |
| 2026-03-31 00:00 |
20:35:17.45 |
-39:59:38.3 |
HIP 101591 |
17.45 |
| 2026-03-31 12:00 |
20:35:28.28 |
-40:00:17.2 |
HIP 101591 |
16.86 |
| 2026-04-01 00:00 |
20:35:39.01 |
-40:00:56.7 |
HIP 101591 |
16.53 |
| 2026-04-01 12:00 |
20:35:49.63 |
-40:01:36.8 |
HIP 101591 |
16.46 |
| 2026-04-02 00:00 |
20:36:00.16 |
-40:02:17.5 |
HIP 101591 |
16.64 |
| 2026-04-02 12:00 |
20:36:10.58 |
-40:02:58.9 |
HIP 101591 |
17.07 |
| 2026-04-03 00:00 |
20:36:20.90 |
-40:03:40.8 |
HIP 101591 |
17.72 |
| 2026-04-03 12:00 |
20:36:31.11 |
-40:04:23.4 |
HIP 101591 |
18.56 |
| 2026-04-04 00:00 |
20:36:41.23 |
-40:05:06.5 |
HIP 101591 |
19.56 |
| 2026-04-04 12:00 |
20:36:51.23 |
-40:05:50.3 |
HIP 101591 |
20.70 |
| 2026-04-05 00:00 |
20:37:01.13 |
-40:06:34.8 |
HIP 101591 |
21.95 |
| 2026-04-05 12:00 |
20:37:10.93 |
-40:07:19.8 |
HIP 101591 |
23.28 |
| 2026-04-06 00:00 |
20:37:20.61 |
-40:08:05.4 |
HIP 101887 |
22.38 |
| 2026-04-06 12:00 |
20:37:30.19 |
-40:08:51.7 |
HIP 101887 |
20.48 |
| 2026-04-07 00:00 |
20:37:39.66 |
-40:09:38.6 |
HIP 101887 |
18.60 |
| 2026-04-07 12:00 |
20:37:49.03 |
-40:10:26.1 |
HIP 101887 |
16.76 |
| 2026-04-08 00:00 |
20:37:58.28 |
-40:11:14.2 |
HIP 101887 |
14.95 |
| 2026-04-08 12:00 |
20:38:07.42 |
-40:12:03.0 |
HIP 101887 |
13.18 |
| 2026-04-09 00:00 |
20:38:16.45 |
-40:12:52.4 |
HIP 101887 |
11.47 |
| 2026-04-09 12:00 |
20:38:25.37 |
-40:13:42.4 |
HIP 101887 |
9.83 |
| 2026-04-10 00:00 |
20:38:34.18 |
-40:14:33.0 |
HIP 101887 |
8.30 |
| 2026-04-10 12:00 |
20:38:42.87 |
-40:15:24.2 |
HIP 101887 |
6.95 |
| 2026-04-11 00:00 |
20:38:51.45 |
-40:16:16.1 |
HIP 101887 |
5.86 |
| 2026-04-11 12:00 |
20:38:59.92 |
-40:17:08.5 |
HIP 101887 |
5.21 |
| 2026-04-12 00:00 |
20:39:08.27 |
-40:18:01.6 |
HIP 101887 |
5.15 |
| 2026-04-12 12:00 |
20:39:16.50 |
-40:18:55.3 |
HIP 101887 |
5.67 |
| 2026-04-13 00:00 |
20:39:24.62 |
-40:19:49.7 |
HIP 101887 |
6.64 |
| 2026-04-13 12:00 |
20:39:32.62 |
-40:20:44.6 |
HIP 101887 |
7.87 |
| 2026-04-14 00:00 |
20:39:40.50 |
-40:21:40.2 |
HIP 101887 |
9.26 |
| 2026-04-14 12:00 |
20:39:48.26 |
-40:22:36.4 |
HIP 101887 |
10.74 |
| 2026-04-15 00:00 |
20:39:55.90 |
-40:23:33.2 |
HIP 101887 |
12.26 |
| 2026-04-15 12:00 |
20:40:03.43 |
-40:24:30.6 |
HIP 101887 |
13.82 |
| 2026-04-16 00:00 |
20:40:10.83 |
-40:25:28.7 |
HIP 102063 |
13.15 |