C/2014 C2 (STEREO)
| Parameter |
Value |
| Designation |
C/2014 C2 (STEREO) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2014-02-18T05:53:19.752000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:48Z |
| Obs used |
297 |
| NEO |
- |
| M1 |
14.400 |
| K1 |
9.300 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-03-08.0000000 |
| e |
1.00000000 |
| q (au) |
0.512340 |
| a (au) |
- |
| i (deg) |
135.502163 |
| Ω (om, deg) |
283.347106 |
| ω (w, deg) |
56.075501 |
| M (ma, deg) |
- |
Magnitude
Scatter + Global Linear
$$
M_a = (15.851 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.851 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-1.000 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2014-01-31 |
2014-02-16 |
-109.8474 |
-24.213 |
| 2014-02-19 |
2014-04-21 |
-4.4994 |
+2.124 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
04:48:25.43 |
-05:25:43.7 |
HIP 22336 |
14.92 |
| 2026-02-03 12:00 |
04:48:23.26 |
-05:25:22.9 |
HIP 22336 |
15.37 |
| 2026-02-04 00:00 |
04:48:21.13 |
-05:25:01.9 |
HIP 22336 |
15.82 |
| 2026-02-04 12:00 |
04:48:19.03 |
-05:24:40.8 |
HIP 22336 |
16.30 |
| 2026-02-05 00:00 |
04:48:16.97 |
-05:24:19.5 |
HIP 22336 |
16.78 |
| 2026-02-05 12:00 |
04:48:14.94 |
-05:23:58.1 |
HIP 22336 |
17.27 |
| 2026-02-06 00:00 |
04:48:12.94 |
-05:23:36.5 |
HIP 22336 |
17.77 |
| 2026-02-06 12:00 |
04:48:10.98 |
-05:23:14.7 |
HIP 22336 |
18.27 |
| 2026-02-07 00:00 |
04:48:09.05 |
-05:22:52.8 |
HIP 22336 |
18.78 |
| 2026-02-07 12:00 |
04:48:07.15 |
-05:22:30.7 |
HIP 22336 |
19.30 |
| 2026-02-08 00:00 |
04:48:05.29 |
-05:22:08.5 |
HIP 22336 |
19.82 |
| 2026-02-08 12:00 |
04:48:03.46 |
-05:21:46.2 |
HIP 22336 |
20.34 |
| 2026-02-09 00:00 |
04:48:01.67 |
-05:21:23.7 |
HIP 22336 |
20.86 |
| 2026-02-09 12:00 |
04:47:59.91 |
-05:21:01.0 |
HIP 22336 |
21.39 |
| 2026-02-10 00:00 |
04:47:58.19 |
-05:20:38.2 |
HIP 22336 |
21.92 |
| 2026-02-10 12:00 |
04:47:56.50 |
-05:20:15.3 |
HIP 22336 |
22.44 |
| 2026-02-11 00:00 |
04:47:54.84 |
-05:19:52.2 |
HIP 22336 |
22.97 |
| 2026-02-11 12:00 |
04:47:53.22 |
-05:19:29.0 |
HIP 22336 |
23.50 |
| 2026-02-12 00:00 |
04:47:51.64 |
-05:19:05.7 |
HIP 22336 |
24.02 |
| 2026-02-12 12:00 |
04:47:50.09 |
-05:18:42.2 |
HIP 22336 |
24.55 |
| 2026-02-13 00:00 |
04:47:48.58 |
-05:18:18.7 |
HIP 22336 |
25.07 |
| 2026-02-13 12:00 |
04:47:47.10 |
-05:17:54.9 |
HIP 22336 |
25.60 |
| 2026-02-14 00:00 |
04:47:45.66 |
-05:17:31.1 |
HIP 22336 |
26.12 |
| 2026-02-14 12:00 |
04:47:44.25 |
-05:17:07.1 |
HIP 22336 |
26.64 |
| 2026-02-15 00:00 |
04:47:42.88 |
-05:16:43.1 |
HIP 22336 |
27.15 |
| 2026-02-15 12:00 |
04:47:41.54 |
-05:16:18.9 |
HIP 22336 |
27.67 |
| 2026-02-16 00:00 |
04:47:40.24 |
-05:15:54.5 |
HIP 22336 |
28.18 |
| 2026-02-16 12:00 |
04:47:38.97 |
-05:15:30.1 |
HIP 22396 |
28.64 |
| 2026-02-17 00:00 |
04:47:37.74 |
-05:15:05.6 |
HIP 22396 |
28.67 |
| 2026-02-17 12:00 |
04:47:36.55 |
-05:14:40.9 |
HIP 22396 |
28.69 |
| 2026-02-18 00:00 |
04:47:35.39 |
-05:14:16.2 |
HIP 22396 |
28.71 |
| 2026-02-18 12:00 |
04:47:34.27 |
-05:13:51.3 |
HIP 22396 |
28.74 |
| 2026-02-19 00:00 |
04:47:33.18 |
-05:13:26.4 |
HIP 22396 |
28.76 |
| 2026-02-19 12:00 |
04:47:32.13 |
-05:13:01.3 |
HIP 22396 |
28.79 |
| 2026-02-20 00:00 |
04:47:31.12 |
-05:12:36.1 |
HIP 22396 |
28.81 |
| 2026-02-20 12:00 |
04:47:30.14 |
-05:12:10.9 |
HIP 22396 |
28.84 |
| 2026-02-21 00:00 |
04:47:29.20 |
-05:11:45.6 |
HIP 22396 |
28.86 |
| 2026-02-21 12:00 |
04:47:28.29 |
-05:11:20.1 |
HIP 22396 |
28.88 |
| 2026-02-22 00:00 |
04:47:27.42 |
-05:10:54.6 |
HIP 22396 |
28.90 |
| 2026-02-22 12:00 |
04:47:26.59 |
-05:10:29.0 |
HIP 22396 |
28.92 |
| 2026-02-23 00:00 |
04:47:25.79 |
-05:10:03.3 |
HIP 22396 |
28.94 |
| 2026-02-23 12:00 |
04:47:25.03 |
-05:09:37.6 |
HIP 22396 |
28.96 |
| 2026-02-24 00:00 |
04:47:24.30 |
-05:09:11.7 |
HIP 22396 |
28.98 |