| Parameter |
Value |
| Designation |
C/1964 N1 (Ikeya) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1964-08-01T05:13:48.668160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:16Z |
| Obs used |
36 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1964-07-28.0000000 |
| e |
0.98529909 |
| q (au) |
0.821742 |
| a (au) |
55.897329 |
| i (deg) |
171.919437 |
| Ω (om, deg) |
269.947994 |
| ω (w, deg) |
290.768689 |
| M (ma, deg) |
359.990052 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.144 + 3.169\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.144 |
| n |
3.169 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
1.000 |
| 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) |
| 2026-07-29 00:00 |
11:19:45.09 |
+12:46:36.9 |
HIP 55428 |
23.34 |
| 2026-07-29 12:00 |
11:19:46.17 |
+12:46:27.8 |
HIP 55428 |
23.04 |
| 2026-07-30 00:00 |
11:19:47.26 |
+12:46:18.7 |
HIP 55428 |
22.73 |
| 2026-07-30 12:00 |
11:19:48.36 |
+12:46:09.5 |
HIP 55428 |
22.43 |
| 2026-07-31 00:00 |
11:19:49.47 |
+12:46:00.4 |
HIP 55428 |
22.12 |
| 2026-07-31 12:00 |
11:19:50.59 |
+12:45:51.2 |
HIP 55428 |
21.81 |
| 2026-08-01 00:00 |
11:19:51.71 |
+12:45:41.9 |
HIP 55428 |
21.49 |
| 2026-08-01 12:00 |
11:19:52.84 |
+12:45:32.7 |
HIP 55428 |
21.18 |
| 2026-08-02 00:00 |
11:19:53.99 |
+12:45:23.4 |
HIP 55428 |
20.86 |
| 2026-08-02 12:00 |
11:19:55.13 |
+12:45:14.1 |
HIP 55428 |
20.54 |
| 2026-08-03 00:00 |
11:19:56.29 |
+12:45:04.7 |
HIP 55428 |
20.22 |
| 2026-08-03 12:00 |
11:19:57.46 |
+12:44:55.4 |
HIP 55428 |
19.90 |
| 2026-08-04 00:00 |
11:19:58.63 |
+12:44:46.0 |
HIP 55428 |
19.58 |
| 2026-08-04 12:00 |
11:19:59.81 |
+12:44:36.6 |
HIP 55428 |
19.25 |
| 2026-08-05 00:00 |
11:20:01.00 |
+12:44:27.1 |
HIP 55428 |
18.92 |
| 2026-08-05 12:00 |
11:20:02.19 |
+12:44:17.7 |
HIP 55428 |
18.59 |
| 2026-08-06 00:00 |
11:20:03.40 |
+12:44:08.2 |
HIP 55428 |
18.26 |
| 2026-08-06 12:00 |
11:20:04.61 |
+12:43:58.7 |
HIP 55428 |
17.93 |
| 2026-08-07 00:00 |
11:20:05.82 |
+12:43:49.2 |
HIP 55428 |
17.60 |
| 2026-08-07 12:00 |
11:20:07.05 |
+12:43:39.6 |
HIP 55428 |
17.26 |
| 2026-08-08 00:00 |
11:20:08.28 |
+12:43:30.1 |
HIP 55428 |
16.93 |
| 2026-08-08 12:00 |
11:20:09.52 |
+12:43:20.5 |
HIP 55428 |
16.59 |
| 2026-08-09 00:00 |
11:20:10.77 |
+12:43:10.9 |
HIP 55428 |
16.25 |
| 2026-08-09 12:00 |
11:20:12.02 |
+12:43:01.2 |
HIP 55428 |
15.91 |
| 2026-08-10 00:00 |
11:20:13.28 |
+12:42:51.6 |
HIP 55428 |
15.57 |
| 2026-08-10 12:00 |
11:20:14.54 |
+12:42:42.0 |
HIP 55428 |
15.22 |
| 2026-08-11 00:00 |
11:20:15.82 |
+12:42:32.3 |
HIP 55428 |
14.88 |
| 2026-08-11 12:00 |
11:20:17.10 |
+12:42:22.6 |
HIP 55428 |
14.53 |
| 2026-08-12 00:00 |
11:20:18.38 |
+12:42:12.9 |
HIP 55428 |
14.19 |
| 2026-08-12 12:00 |
11:20:19.67 |
+12:42:03.2 |
HIP 55428 |
13.84 |
| 2026-08-13 00:00 |
11:20:20.97 |
+12:41:53.5 |
HIP 55428 |
13.49 |
| 2026-08-13 12:00 |
11:20:22.28 |
+12:41:43.7 |
HIP 55428 |
13.14 |
| 2026-08-14 00:00 |
11:20:23.59 |
+12:41:34.0 |
HIP 55428 |
12.79 |
| 2026-08-14 12:00 |
11:20:24.91 |
+12:41:24.2 |
HIP 55428 |
12.44 |
| 2026-08-15 00:00 |
11:20:26.23 |
+12:41:14.5 |
HIP 55428 |
12.09 |
| 2026-08-15 12:00 |
11:20:27.56 |
+12:41:04.7 |
HIP 55428 |
11.73 |
| 2026-08-16 00:00 |
11:20:28.89 |
+12:40:54.9 |
HIP 55428 |
11.38 |
| 2026-08-16 12:00 |
11:20:30.23 |
+12:40:45.1 |
HIP 55428 |
11.03 |
| 2026-08-17 00:00 |
11:20:31.57 |
+12:40:35.3 |
HIP 55428 |
10.67 |
| 2026-08-17 12:00 |
11:20:32.92 |
+12:40:25.5 |
HIP 55428 |
10.32 |
| 2026-08-18 00:00 |
11:20:34.28 |
+12:40:15.7 |
HIP 55428 |
9.97 |
| 2026-08-18 12:00 |
11:20:35.64 |
+12:40:05.9 |
HIP 55428 |
9.61 |
| 2026-08-19 00:00 |
11:20:37.01 |
+12:39:56.1 |
HIP 55428 |
9.26 |