| Parameter |
Value |
| Designation |
C/1963 F1 (Alcock) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1963-05-05T21:06:43.280640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:17Z |
| Obs used |
25 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1963-05-15.0000000 |
| e |
0.99791950 |
| q (au) |
1.537080 |
| a (au) |
738.804223 |
| i (deg) |
86.218793 |
| Ω (om, deg) |
43.465153 |
| ω (w, deg) |
146.621136 |
| M (ma, deg) |
0.000448 |
Magnitude
Scatter + Global Linear
$$
M_a = (4.297 + 5.819\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
4.297 |
| n |
5.819 |
| gf |
1.000 |
| gb |
-0.539 |
| 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) |
| 2026-09-25 00:00 |
03:33:37.24 |
-31:09:01.7 |
HIP 16628 |
5.94 |
| 2026-09-25 12:00 |
03:33:36.29 |
-31:09:15.8 |
HIP 16628 |
6.25 |
| 2026-09-26 00:00 |
03:33:35.33 |
-31:09:29.8 |
HIP 16628 |
6.56 |
| 2026-09-26 12:00 |
03:33:34.36 |
-31:09:43.8 |
HIP 16628 |
6.87 |
| 2026-09-27 00:00 |
03:33:33.38 |
-31:09:57.8 |
HIP 16628 |
7.18 |
| 2026-09-27 12:00 |
03:33:32.39 |
-31:10:11.6 |
HIP 16628 |
7.50 |
| 2026-09-28 00:00 |
03:33:31.39 |
-31:10:25.5 |
HIP 16628 |
7.81 |
| 2026-09-28 12:00 |
03:33:30.38 |
-31:10:39.2 |
HIP 16628 |
8.13 |
| 2026-09-29 00:00 |
03:33:29.35 |
-31:10:52.9 |
HIP 16628 |
8.44 |
| 2026-09-29 12:00 |
03:33:28.32 |
-31:11:06.5 |
HIP 16628 |
8.76 |
| 2026-09-30 00:00 |
03:33:27.27 |
-31:11:20.0 |
HIP 16628 |
9.08 |
| 2026-09-30 12:00 |
03:33:26.22 |
-31:11:33.5 |
HIP 16628 |
9.40 |
| 2026-10-01 00:00 |
03:33:25.16 |
-31:11:46.9 |
HIP 16628 |
9.72 |
| 2026-10-01 12:00 |
03:33:24.08 |
-31:12:00.3 |
HIP 16628 |
10.04 |
| 2026-10-02 00:00 |
03:33:23.00 |
-31:12:13.6 |
HIP 16628 |
10.36 |
| 2026-10-02 12:00 |
03:33:21.90 |
-31:12:26.8 |
HIP 16628 |
10.68 |
| 2026-10-03 00:00 |
03:33:20.80 |
-31:12:39.9 |
HIP 16628 |
11.00 |
| 2026-10-03 12:00 |
03:33:19.68 |
-31:12:52.9 |
HIP 16628 |
11.32 |
| 2026-10-04 00:00 |
03:33:18.56 |
-31:13:05.9 |
HIP 16628 |
11.64 |
| 2026-10-04 12:00 |
03:33:17.42 |
-31:13:18.8 |
HIP 16628 |
11.97 |
| 2026-10-05 00:00 |
03:33:16.28 |
-31:13:31.6 |
HIP 16628 |
12.29 |
| 2026-10-05 12:00 |
03:33:15.13 |
-31:13:44.4 |
HIP 16628 |
12.61 |
| 2026-10-06 00:00 |
03:33:13.96 |
-31:13:57.0 |
HIP 16628 |
12.94 |
| 2026-10-06 12:00 |
03:33:12.79 |
-31:14:09.6 |
HIP 16628 |
13.27 |
| 2026-10-07 00:00 |
03:33:11.61 |
-31:14:22.1 |
HIP 16628 |
13.59 |
| 2026-10-07 12:00 |
03:33:10.42 |
-31:14:34.5 |
HIP 16628 |
13.92 |
| 2026-10-08 00:00 |
03:33:09.22 |
-31:14:46.8 |
HIP 16628 |
14.25 |
| 2026-10-08 12:00 |
03:33:08.01 |
-31:14:59.1 |
HIP 16628 |
14.57 |
| 2026-10-09 00:00 |
03:33:06.79 |
-31:15:11.2 |
HIP 16628 |
14.90 |
| 2026-10-09 12:00 |
03:33:05.56 |
-31:15:23.3 |
HIP 16628 |
15.23 |
| 2026-10-10 00:00 |
03:33:04.33 |
-31:15:35.3 |
HIP 16628 |
15.56 |
| 2026-10-10 12:00 |
03:33:03.08 |
-31:15:47.2 |
HIP 16628 |
15.89 |
| 2026-10-11 00:00 |
03:33:01.83 |
-31:15:59.0 |
HIP 16628 |
16.22 |
| 2026-10-11 12:00 |
03:33:00.57 |
-31:16:10.7 |
HIP 16628 |
16.55 |
| 2026-10-12 00:00 |
03:32:59.30 |
-31:16:22.3 |
HIP 16628 |
16.88 |
| 2026-10-12 12:00 |
03:32:58.02 |
-31:16:33.8 |
HIP 16628 |
17.21 |
| 2026-10-13 00:00 |
03:32:56.73 |
-31:16:45.2 |
HIP 16628 |
17.54 |
| 2026-10-13 12:00 |
03:32:55.44 |
-31:16:56.6 |
HIP 16628 |
17.87 |
| 2026-10-14 00:00 |
03:32:54.14 |
-31:17:07.8 |
HIP 16628 |
18.20 |
| 2026-10-14 12:00 |
03:32:52.83 |
-31:17:18.9 |
HIP 16628 |
18.53 |
| 2026-10-15 00:00 |
03:32:51.51 |
-31:17:30.0 |
HIP 16481 |
18.63 |
| 2026-10-15 12:00 |
03:32:50.18 |
-31:17:40.9 |
HIP 16481 |
18.34 |
| 2026-10-16 00:00 |
03:32:48.85 |
-31:17:51.7 |
HIP 16481 |
18.06 |