| Parameter |
Value |
| Designation |
C/2014 F2 (Tenagra) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-01-02T07:05:02.428800Z |
| Orbit solution date (soln_date, UTC) |
2022-06-07T21:44:07Z |
| Obs used |
300 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
13.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-08-06.0000000 |
| e |
0.97089096 |
| q (au) |
4.314459 |
| a (au) |
148.217132 |
| i (deg) |
119.061202 |
| Ω (om, deg) |
267.449809 |
| ω (w, deg) |
86.041144 |
| M (ma, deg) |
359.918454 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.988 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.988 |
| n |
6.000 |
| gf |
0.997 |
| gb |
-0.593 |
| k |
0.800 |
| δ90 |
9.999 |
| 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 |
| 2013-06-19 |
2014-10-02 |
+8.8067 |
-5.851 |
| 2015-02-09 |
2015-12-10 |
-5.8147 |
+3.628 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
04:37:17.47 |
-09:38:29.9 |
HIP 21536 |
12.71 |
| 2026-05-12 12:00 |
04:37:21.63 |
-09:38:17.1 |
HIP 21536 |
12.79 |
| 2026-05-13 00:00 |
04:37:25.81 |
-09:38:04.6 |
HIP 21536 |
12.94 |
| 2026-05-13 12:00 |
04:37:29.99 |
-09:37:52.4 |
HIP 21536 |
13.18 |
| 2026-05-14 00:00 |
04:37:34.19 |
-09:37:40.5 |
HIP 21536 |
13.49 |
| 2026-05-14 12:00 |
04:37:38.40 |
-09:37:28.8 |
HIP 21536 |
13.87 |
| 2026-05-15 00:00 |
04:37:42.61 |
-09:37:17.4 |
HIP 21536 |
14.31 |
| 2026-05-15 12:00 |
04:37:46.84 |
-09:37:06.3 |
HIP 21536 |
14.81 |
| 2026-05-16 00:00 |
04:37:51.08 |
-09:36:55.5 |
HIP 21536 |
15.36 |
| 2026-05-16 12:00 |
04:37:55.33 |
-09:36:45.0 |
HIP 21536 |
15.97 |
| 2026-05-17 00:00 |
04:37:59.59 |
-09:36:34.7 |
HIP 21536 |
16.61 |
| 2026-05-17 12:00 |
04:38:03.86 |
-09:36:24.7 |
HIP 21536 |
17.30 |
| 2026-05-18 00:00 |
04:38:08.14 |
-09:36:15.0 |
HIP 21625 |
16.92 |
| 2026-05-18 12:00 |
04:38:12.43 |
-09:36:05.6 |
HIP 21625 |
16.40 |
| 2026-05-19 00:00 |
04:38:16.72 |
-09:35:56.5 |
HIP 21625 |
15.94 |
| 2026-05-19 12:00 |
04:38:21.02 |
-09:35:47.7 |
HIP 21625 |
15.54 |
| 2026-05-20 00:00 |
04:38:25.33 |
-09:35:39.2 |
HIP 21625 |
15.22 |
| 2026-05-20 12:00 |
04:38:29.65 |
-09:35:30.9 |
HIP 21625 |
14.96 |
| 2026-05-21 00:00 |
04:38:33.98 |
-09:35:23.0 |
HIP 21625 |
14.79 |
| 2026-05-21 12:00 |
04:38:38.31 |
-09:35:15.3 |
HIP 21625 |
14.70 |
| 2026-05-22 00:00 |
04:38:42.65 |
-09:35:07.9 |
HIP 21625 |
14.69 |
| 2026-05-22 12:00 |
04:38:46.99 |
-09:35:00.9 |
HIP 21625 |
14.76 |
| 2026-05-23 00:00 |
04:38:51.34 |
-09:34:54.1 |
HIP 21625 |
14.92 |
| 2026-05-23 12:00 |
04:38:55.69 |
-09:34:47.6 |
HIP 21625 |
15.16 |
| 2026-05-24 00:00 |
04:39:00.05 |
-09:34:41.4 |
HIP 21625 |
15.48 |
| 2026-05-24 12:00 |
04:39:04.42 |
-09:34:35.5 |
HIP 21625 |
15.86 |
| 2026-05-25 00:00 |
04:39:08.79 |
-09:34:29.9 |
HIP 21625 |
16.32 |
| 2026-05-25 12:00 |
04:39:13.16 |
-09:34:24.6 |
HIP 21625 |
16.84 |
| 2026-05-26 00:00 |
04:39:17.54 |
-09:34:19.6 |
HIP 21625 |
17.41 |
| 2026-05-26 12:00 |
04:39:21.92 |
-09:34:14.9 |
HIP 21625 |
18.03 |
| 2026-05-27 00:00 |
04:39:26.31 |
-09:34:10.4 |
HIP 21625 |
18.70 |
| 2026-05-27 12:00 |
04:39:30.70 |
-09:34:06.3 |
HIP 21625 |
19.42 |
| 2026-05-28 00:00 |
04:39:35.09 |
-09:34:02.5 |
HIP 21625 |
20.17 |
| 2026-05-28 12:00 |
04:39:39.48 |
-09:33:59.0 |
HIP 21625 |
20.95 |
| 2026-05-29 00:00 |
04:39:43.88 |
-09:33:55.8 |
HIP 21625 |
21.76 |
| 2026-05-29 12:00 |
04:39:48.28 |
-09:33:52.9 |
HIP 21625 |
22.60 |
| 2026-05-30 00:00 |
04:39:52.68 |
-09:33:50.2 |
HIP 21625 |
23.46 |
| 2026-05-30 12:00 |
04:39:57.08 |
-09:33:47.9 |
HIP 21765 |
23.44 |
| 2026-05-31 00:00 |
04:40:01.48 |
-09:33:45.9 |
HIP 21765 |
23.06 |
| 2026-05-31 12:00 |
04:40:05.88 |
-09:33:44.2 |
HIP 21765 |
22.73 |
| 2026-06-01 00:00 |
04:40:10.29 |
-09:33:42.8 |
HIP 21765 |
22.46 |
| 2026-06-01 12:00 |
04:40:14.69 |
-09:33:41.7 |
HIP 21765 |
22.24 |
| 2026-06-02 00:00 |
04:40:19.09 |
-09:33:40.9 |
HIP 21765 |
22.08 |