| Parameter |
Value |
| Designation |
C/2016 N4 (MASTER) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-09-16T14:17:55.443840Z |
| Orbit solution date (soln_date, UTC) |
2022-07-31T01:42:28Z |
| Obs used |
2084 |
| NEO |
- |
| M1 |
11.100 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2017-09-11.0000000 |
| e |
0.99939359 |
| q (au) |
3.199121 |
| a (au) |
5275.516225 |
| i (deg) |
72.557241 |
| Ω (om, deg) |
354.031309 |
| ω (w, deg) |
55.954990 |
| M (ma, deg) |
359.999986 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.927 + 2.762\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.927 |
| n |
2.762 |
| gf |
0.997 |
| gb |
-0.817 |
| 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 |
| 2015-09-11 |
2016-10-30 |
+2.0258 |
-1.477 |
| 2016-10-30 |
2017-09-16 |
-2.1552 |
+0.913 |
| 2017-09-16 |
2020-03-26 |
+1.1161 |
-0.650 |
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 |
11:24:53.69 |
-06:53:37.5 |
HIP 55635 |
21.70 |
| 2026-05-12 12:00 |
11:24:51.02 |
-06:53:17.7 |
HIP 55635 |
21.47 |
| 2026-05-13 00:00 |
11:24:48.39 |
-06:52:58.2 |
HIP 55635 |
21.26 |
| 2026-05-13 12:00 |
11:24:45.80 |
-06:52:38.8 |
HIP 55635 |
21.09 |
| 2026-05-14 00:00 |
11:24:43.25 |
-06:52:19.7 |
HIP 55635 |
20.94 |
| 2026-05-14 12:00 |
11:24:40.75 |
-06:52:00.8 |
HIP 55635 |
20.82 |
| 2026-05-15 00:00 |
11:24:38.28 |
-06:51:42.0 |
HIP 55635 |
20.73 |
| 2026-05-15 12:00 |
11:24:35.86 |
-06:51:23.5 |
HIP 55635 |
20.65 |
| 2026-05-16 00:00 |
11:24:33.49 |
-06:51:05.2 |
HIP 55635 |
20.61 |
| 2026-05-16 12:00 |
11:24:31.16 |
-06:50:47.1 |
HIP 55635 |
20.59 |
| 2026-05-17 00:00 |
11:24:28.87 |
-06:50:29.3 |
HIP 55635 |
20.59 |
| 2026-05-17 12:00 |
11:24:26.62 |
-06:50:11.6 |
HIP 55635 |
20.61 |
| 2026-05-18 00:00 |
11:24:24.42 |
-06:49:54.2 |
HIP 55635 |
20.65 |
| 2026-05-18 12:00 |
11:24:22.26 |
-06:49:36.9 |
HIP 55635 |
20.71 |
| 2026-05-19 00:00 |
11:24:20.14 |
-06:49:19.9 |
HIP 55635 |
20.78 |
| 2026-05-19 12:00 |
11:24:18.07 |
-06:49:03.2 |
HIP 55635 |
20.88 |
| 2026-05-20 00:00 |
11:24:16.04 |
-06:48:46.6 |
HIP 55635 |
20.99 |
| 2026-05-20 12:00 |
11:24:14.06 |
-06:48:30.3 |
HIP 55635 |
21.11 |
| 2026-05-21 00:00 |
11:24:12.12 |
-06:48:14.2 |
HIP 55635 |
21.25 |
| 2026-05-21 12:00 |
11:24:10.22 |
-06:47:58.4 |
HIP 55635 |
21.40 |
| 2026-05-22 00:00 |
11:24:08.37 |
-06:47:42.8 |
HIP 55635 |
21.56 |
| 2026-05-22 12:00 |
11:24:06.56 |
-06:47:27.4 |
HIP 55635 |
21.73 |
| 2026-05-23 00:00 |
11:24:04.80 |
-06:47:12.2 |
HIP 55635 |
21.91 |
| 2026-05-23 12:00 |
11:24:03.08 |
-06:46:57.3 |
HIP 55635 |
22.09 |
| 2026-05-24 00:00 |
11:24:01.40 |
-06:46:42.7 |
HIP 55635 |
22.28 |
| 2026-05-24 12:00 |
11:23:59.77 |
-06:46:28.2 |
HIP 55635 |
22.48 |
| 2026-05-25 00:00 |
11:23:58.18 |
-06:46:14.0 |
HIP 55635 |
22.69 |
| 2026-05-25 12:00 |
11:23:56.64 |
-06:46:00.1 |
HIP 55635 |
22.89 |
| 2026-05-26 00:00 |
11:23:55.14 |
-06:45:46.4 |
HIP 55635 |
23.10 |
| 2026-05-26 12:00 |
11:23:53.69 |
-06:45:32.9 |
HIP 55635 |
23.32 |
| 2026-05-27 00:00 |
11:23:52.28 |
-06:45:19.7 |
HIP 55635 |
23.53 |
| 2026-05-27 12:00 |
11:23:50.91 |
-06:45:06.8 |
HIP 55635 |
23.75 |
| 2026-05-28 00:00 |
11:23:49.59 |
-06:44:54.0 |
HIP 55635 |
23.96 |
| 2026-05-28 12:00 |
11:23:48.31 |
-06:44:41.6 |
HIP 55635 |
24.18 |
| 2026-05-29 00:00 |
11:23:47.08 |
-06:44:29.3 |
HIP 55635 |
24.39 |
| 2026-05-29 12:00 |
11:23:45.89 |
-06:44:17.4 |
HIP 55635 |
24.61 |
| 2026-05-30 00:00 |
11:23:44.74 |
-06:44:05.7 |
HIP 55635 |
24.82 |
| 2026-05-30 12:00 |
11:23:43.64 |
-06:43:54.2 |
HIP 55635 |
25.03 |
| 2026-05-31 00:00 |
11:23:42.59 |
-06:43:43.0 |
HIP 55635 |
25.24 |
| 2026-05-31 12:00 |
11:23:41.57 |
-06:43:32.0 |
HIP 55635 |
25.44 |
| 2026-06-01 00:00 |
11:23:40.60 |
-06:43:21.3 |
HIP 55635 |
25.64 |
| 2026-06-01 12:00 |
11:23:39.68 |
-06:43:10.9 |
HIP 55635 |
25.84 |
| 2026-06-02 00:00 |
11:23:38.80 |
-06:43:00.7 |
HIP 55635 |
26.03 |