C/1915 C1 (Mellish)
| Parameter |
Value |
| Designation |
C/1915 C1 (Mellish) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1915-07-17T15:36:50.613120Z |
| Orbit solution date (soln_date, UTC) |
2024-04-15T15:43:28Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
7.700 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1915-06-30.0000000 |
| e |
1.00027442 |
| q (au) |
1.005324 |
| a (au) |
-3663.395604 |
| i (deg) |
54.791644 |
| Ω (om, deg) |
73.453125 |
| ω (w, deg) |
247.782134 |
| M (ma, deg) |
-0.000078 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.514 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.514 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.852 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
08:57:13.93 |
+63:34:43.8 |
HIP 44107 |
14.93 |
| 2026-02-03 12:00 |
08:57:11.90 |
+63:34:46.2 |
HIP 44107 |
15.13 |
| 2026-02-04 00:00 |
08:57:09.87 |
+63:34:48.6 |
HIP 43793 |
15.06 |
| 2026-02-04 12:00 |
08:57:07.85 |
+63:34:50.8 |
HIP 43793 |
14.87 |
| 2026-02-05 00:00 |
08:57:05.82 |
+63:34:53.0 |
HIP 43793 |
14.69 |
| 2026-02-05 12:00 |
08:57:03.80 |
+63:34:55.1 |
HIP 43793 |
14.50 |
| 2026-02-06 00:00 |
08:57:01.78 |
+63:34:57.1 |
HIP 43793 |
14.32 |
| 2026-02-06 12:00 |
08:56:59.75 |
+63:34:59.0 |
HIP 43793 |
14.14 |
| 2026-02-07 00:00 |
08:56:57.74 |
+63:35:00.8 |
HIP 43793 |
13.96 |
| 2026-02-07 12:00 |
08:56:55.72 |
+63:35:02.5 |
HIP 43793 |
13.78 |
| 2026-02-08 00:00 |
08:56:53.70 |
+63:35:04.1 |
HIP 43793 |
13.60 |
| 2026-02-08 12:00 |
08:56:51.69 |
+63:35:05.6 |
HIP 43793 |
13.42 |
| 2026-02-09 00:00 |
08:56:49.68 |
+63:35:07.0 |
HIP 43793 |
13.24 |
| 2026-02-09 12:00 |
08:56:47.67 |
+63:35:08.4 |
HIP 43793 |
13.06 |
| 2026-02-10 00:00 |
08:56:45.67 |
+63:35:09.6 |
HIP 43793 |
12.88 |
| 2026-02-10 12:00 |
08:56:43.66 |
+63:35:10.8 |
HIP 43793 |
12.71 |
| 2026-02-11 00:00 |
08:56:41.66 |
+63:35:11.8 |
HIP 43793 |
12.53 |
| 2026-02-11 12:00 |
08:56:39.67 |
+63:35:12.8 |
HIP 43793 |
12.36 |
| 2026-02-12 00:00 |
08:56:37.67 |
+63:35:13.6 |
HIP 43793 |
12.19 |
| 2026-02-12 12:00 |
08:56:35.68 |
+63:35:14.4 |
HIP 43793 |
12.01 |
| 2026-02-13 00:00 |
08:56:33.70 |
+63:35:15.1 |
HIP 43793 |
11.84 |
| 2026-02-13 12:00 |
08:56:31.72 |
+63:35:15.6 |
HIP 43793 |
11.67 |
| 2026-02-14 00:00 |
08:56:29.74 |
+63:35:16.1 |
HIP 43793 |
11.51 |
| 2026-02-14 12:00 |
08:56:27.76 |
+63:35:16.5 |
HIP 43793 |
11.34 |
| 2026-02-15 00:00 |
08:56:25.79 |
+63:35:16.8 |
HIP 43793 |
11.17 |
| 2026-02-15 12:00 |
08:56:23.83 |
+63:35:17.0 |
HIP 43793 |
11.01 |
| 2026-02-16 00:00 |
08:56:21.87 |
+63:35:17.1 |
HIP 43793 |
10.84 |
| 2026-02-16 12:00 |
08:56:19.91 |
+63:35:17.1 |
HIP 43793 |
10.68 |
| 2026-02-17 00:00 |
08:56:17.96 |
+63:35:17.0 |
HIP 43793 |
10.52 |
| 2026-02-17 12:00 |
08:56:16.02 |
+63:35:16.8 |
HIP 43793 |
10.36 |
| 2026-02-18 00:00 |
08:56:14.08 |
+63:35:16.6 |
HIP 43793 |
10.20 |
| 2026-02-18 12:00 |
08:56:12.14 |
+63:35:16.2 |
HIP 43793 |
10.04 |
| 2026-02-19 00:00 |
08:56:10.21 |
+63:35:15.7 |
HIP 43793 |
9.89 |
| 2026-02-19 12:00 |
08:56:08.29 |
+63:35:15.2 |
HIP 43793 |
9.74 |
| 2026-02-20 00:00 |
08:56:06.37 |
+63:35:14.5 |
HIP 43793 |
9.58 |
| 2026-02-20 12:00 |
08:56:04.46 |
+63:35:13.8 |
HIP 43793 |
9.43 |
| 2026-02-21 00:00 |
08:56:02.56 |
+63:35:12.9 |
HIP 43793 |
9.28 |
| 2026-02-21 12:00 |
08:56:00.66 |
+63:35:12.0 |
HIP 43793 |
9.14 |
| 2026-02-22 00:00 |
08:55:58.77 |
+63:35:11.0 |
HIP 43793 |
8.99 |
| 2026-02-22 12:00 |
08:55:56.88 |
+63:35:09.9 |
HIP 43793 |
8.85 |
| 2026-02-23 00:00 |
08:55:55.00 |
+63:35:08.6 |
HIP 43793 |
8.71 |
| 2026-02-23 12:00 |
08:55:53.13 |
+63:35:07.3 |
HIP 43793 |
8.57 |
| 2026-02-24 00:00 |
08:55:51.27 |
+63:35:05.9 |
HIP 43793 |
8.43 |