| Parameter |
Value |
| Designation |
C/2015 F5 (SWAN-Xingming) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-03-28T02:23:27.029760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:09Z |
| Obs used |
209 |
| NEO |
Yes |
| M1 |
14.100 |
| K1 |
4.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-04-22.0000000 |
| e |
0.97774875 |
| q (au) |
0.346004 |
| a (au) |
15.549862 |
| i (deg) |
149.256648 |
| Ω (om, deg) |
287.739679 |
| ω (w, deg) |
13.393236 |
| M (ma, deg) |
0.400240 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.117 + 4.165\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.117 |
| n |
4.165 |
| gf |
1.000 |
| 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 |
| 2015-04-04 |
2015-06-07 |
-4.5612 |
-1.918 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
06:48:33.17 |
+20:05:53.1 |
HIP 32676 |
28.51 |
| 2026-06-01 12:00 |
06:48:37.59 |
+20:05:48.4 |
HIP 32676 |
28.40 |
| 2026-06-02 00:00 |
06:48:42.03 |
+20:05:43.6 |
HIP 32676 |
28.33 |
| 2026-06-02 12:00 |
06:48:46.49 |
+20:05:38.7 |
HIP 32676 |
28.30 |
| 2026-06-03 00:00 |
06:48:50.97 |
+20:05:33.8 |
HIP 32676 |
28.31 |
| 2026-06-03 12:00 |
06:48:55.47 |
+20:05:28.8 |
HIP 32852 |
27.63 |
| 2026-06-04 00:00 |
06:49:00.00 |
+20:05:23.8 |
HIP 32852 |
26.58 |
| 2026-06-04 12:00 |
06:49:04.53 |
+20:05:18.7 |
HIP 32852 |
25.52 |
| 2026-06-05 00:00 |
06:49:09.09 |
+20:05:13.6 |
HIP 32852 |
24.46 |
| 2026-06-05 12:00 |
06:49:13.67 |
+20:05:08.4 |
HIP 32852 |
23.40 |
| 2026-06-06 00:00 |
06:49:18.26 |
+20:05:03.1 |
HIP 32852 |
22.33 |
| 2026-06-06 12:00 |
06:49:22.88 |
+20:04:57.8 |
HIP 32852 |
21.26 |
| 2026-06-07 00:00 |
06:49:27.51 |
+20:04:52.4 |
HIP 32852 |
20.19 |
| 2026-06-07 12:00 |
06:49:32.16 |
+20:04:47.0 |
HIP 32852 |
19.11 |
| 2026-06-08 00:00 |
06:49:36.82 |
+20:04:41.5 |
HIP 32852 |
18.03 |
| 2026-06-08 12:00 |
06:49:41.51 |
+20:04:35.9 |
HIP 32852 |
16.96 |
| 2026-06-09 00:00 |
06:49:46.21 |
+20:04:30.3 |
HIP 32852 |
15.88 |
| 2026-06-09 12:00 |
06:49:50.92 |
+20:04:24.7 |
HIP 32852 |
14.80 |
| 2026-06-10 00:00 |
06:49:55.66 |
+20:04:18.9 |
HIP 32852 |
13.73 |
| 2026-06-10 12:00 |
06:50:00.40 |
+20:04:13.2 |
HIP 32852 |
12.65 |
| 2026-06-11 00:00 |
06:50:05.17 |
+20:04:07.3 |
HIP 32852 |
11.59 |
| 2026-06-11 12:00 |
06:50:09.94 |
+20:04:01.4 |
HIP 32852 |
10.53 |
| 2026-06-12 00:00 |
06:50:14.74 |
+20:03:55.5 |
HIP 32852 |
9.48 |
| 2026-06-12 12:00 |
06:50:19.54 |
+20:03:49.5 |
HIP 32852 |
8.45 |
| 2026-06-13 00:00 |
06:50:24.37 |
+20:03:43.4 |
HIP 32852 |
7.45 |
| 2026-06-13 12:00 |
06:50:29.20 |
+20:03:37.3 |
HIP 32852 |
6.48 |
| 2026-06-14 00:00 |
06:50:34.05 |
+20:03:31.2 |
HIP 32852 |
5.59 |
| 2026-06-14 12:00 |
06:50:38.91 |
+20:03:24.9 |
HIP 32852 |
4.79 |
| 2026-06-15 00:00 |
06:50:43.78 |
+20:03:18.7 |
HIP 32852 |
4.17 |
| 2026-06-15 12:00 |
06:50:48.67 |
+20:03:12.3 |
HIP 32852 |
3.79 |
| 2026-06-16 00:00 |
06:50:53.57 |
+20:03:05.9 |
HIP 32852 |
3.75 |
| 2026-06-16 12:00 |
06:50:58.48 |
+20:02:59.5 |
HIP 32852 |
4.05 |
| 2026-06-17 00:00 |
06:51:03.40 |
+20:02:53.0 |
HIP 32852 |
4.63 |
| 2026-06-17 12:00 |
06:51:08.33 |
+20:02:46.4 |
HIP 32852 |
5.40 |
| 2026-06-18 00:00 |
06:51:13.27 |
+20:02:39.8 |
HIP 32852 |
6.29 |
| 2026-06-18 12:00 |
06:51:18.22 |
+20:02:33.2 |
HIP 32852 |
7.27 |
| 2026-06-19 00:00 |
06:51:23.19 |
+20:02:26.5 |
HIP 32852 |
8.30 |
| 2026-06-19 12:00 |
06:51:28.16 |
+20:02:19.7 |
HIP 32852 |
9.36 |
| 2026-06-20 00:00 |
06:51:33.14 |
+20:02:12.9 |
HIP 32852 |
10.45 |
| 2026-06-20 12:00 |
06:51:38.13 |
+20:02:06.1 |
HIP 32852 |
11.55 |
| 2026-06-21 00:00 |
06:51:43.12 |
+20:01:59.2 |
HIP 32852 |
12.67 |
| 2026-06-21 12:00 |
06:51:48.13 |
+20:01:52.2 |
HIP 32852 |
13.81 |
| 2026-06-22 00:00 |
06:51:53.14 |
+20:01:45.2 |
HIP 32852 |
14.95 |