C/1964 P1 (Everhart)
| Parameter |
Value |
| Designation |
C/1964 P1 (Everhart) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1964-08-23T04:28:19.128000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:16Z |
| Obs used |
40 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1964-10-14.0000000 |
| e |
0.99649619 |
| q (au) |
1.259279 |
| a (au) |
359.402401 |
| i (deg) |
67.969012 |
| Ω (om, deg) |
280.445182 |
| ω (w, deg) |
20.685810 |
| M (ma, deg) |
0.007495 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.997 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.997 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| k |
1.000 |
| 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 |
06:53:13.28 |
+15:38:17.4 |
HIP 33039 |
3.35 |
| 2026-02-03 12:00 |
06:53:12.01 |
+15:38:20.1 |
HIP 33039 |
3.06 |
| 2026-02-04 00:00 |
06:53:10.74 |
+15:38:22.8 |
HIP 33039 |
2.79 |
| 2026-02-04 12:00 |
06:53:09.49 |
+15:38:25.6 |
HIP 33039 |
2.52 |
| 2026-02-05 00:00 |
06:53:08.24 |
+15:38:28.3 |
HIP 33039 |
2.26 |
| 2026-02-05 12:00 |
06:53:06.99 |
+15:38:31.1 |
HIP 33039 |
2.02 |
| 2026-02-06 00:00 |
06:53:05.76 |
+15:38:33.9 |
HIP 33039 |
1.79 |
| 2026-02-06 12:00 |
06:53:04.53 |
+15:38:36.7 |
HIP 33039 |
1.60 |
| 2026-02-07 00:00 |
06:53:03.31 |
+15:38:39.4 |
HIP 33039 |
1.44 |
| 2026-02-07 12:00 |
06:53:02.10 |
+15:38:42.2 |
HIP 33039 |
1.33 |
| 2026-02-08 00:00 |
06:53:00.89 |
+15:38:45.1 |
HIP 33039 |
1.28 |
| 2026-02-08 12:00 |
06:52:59.70 |
+15:38:47.9 |
HIP 33039 |
1.30 |
| 2026-02-09 00:00 |
06:52:58.51 |
+15:38:50.7 |
HIP 33039 |
1.38 |
| 2026-02-09 12:00 |
06:52:57.33 |
+15:38:53.5 |
HIP 33039 |
1.51 |
| 2026-02-10 00:00 |
06:52:56.15 |
+15:38:56.4 |
HIP 33039 |
1.68 |
| 2026-02-10 12:00 |
06:52:54.99 |
+15:38:59.2 |
HIP 33039 |
1.88 |
| 2026-02-11 00:00 |
06:52:53.83 |
+15:39:02.1 |
HIP 33039 |
2.09 |
| 2026-02-11 12:00 |
06:52:52.69 |
+15:39:04.9 |
HIP 33039 |
2.32 |
| 2026-02-12 00:00 |
06:52:51.55 |
+15:39:07.8 |
HIP 33039 |
2.56 |
| 2026-02-12 12:00 |
06:52:50.42 |
+15:39:10.7 |
HIP 33039 |
2.80 |
| 2026-02-13 00:00 |
06:52:49.30 |
+15:39:13.5 |
HIP 33039 |
3.05 |
| 2026-02-13 12:00 |
06:52:48.18 |
+15:39:16.4 |
HIP 33039 |
3.30 |
| 2026-02-14 00:00 |
06:52:47.08 |
+15:39:19.3 |
HIP 33039 |
3.55 |
| 2026-02-14 12:00 |
06:52:45.99 |
+15:39:22.2 |
HIP 33039 |
3.81 |
| 2026-02-15 00:00 |
06:52:44.90 |
+15:39:25.1 |
HIP 33039 |
4.06 |
| 2026-02-15 12:00 |
06:52:43.83 |
+15:39:28.0 |
HIP 33039 |
4.31 |
| 2026-02-16 00:00 |
06:52:42.76 |
+15:39:30.9 |
HIP 33039 |
4.56 |
| 2026-02-16 12:00 |
06:52:41.70 |
+15:39:33.8 |
HIP 33039 |
4.81 |
| 2026-02-17 00:00 |
06:52:40.65 |
+15:39:36.7 |
HIP 33039 |
5.06 |
| 2026-02-17 12:00 |
06:52:39.61 |
+15:39:39.7 |
HIP 33039 |
5.31 |
| 2026-02-18 00:00 |
06:52:38.59 |
+15:39:42.6 |
HIP 33039 |
5.55 |
| 2026-02-18 12:00 |
06:52:37.57 |
+15:39:45.5 |
HIP 33039 |
5.80 |
| 2026-02-19 00:00 |
06:52:36.56 |
+15:39:48.4 |
HIP 33039 |
6.04 |
| 2026-02-19 12:00 |
06:52:35.56 |
+15:39:51.4 |
HIP 33039 |
6.28 |
| 2026-02-20 00:00 |
06:52:34.57 |
+15:39:54.3 |
HIP 33039 |
6.52 |
| 2026-02-20 12:00 |
06:52:33.59 |
+15:39:57.2 |
HIP 33039 |
6.76 |
| 2026-02-21 00:00 |
06:52:32.62 |
+15:40:00.2 |
HIP 33039 |
7.00 |
| 2026-02-21 12:00 |
06:52:31.66 |
+15:40:03.1 |
HIP 33039 |
7.23 |
| 2026-02-22 00:00 |
06:52:30.71 |
+15:40:06.1 |
HIP 33039 |
7.46 |
| 2026-02-22 12:00 |
06:52:29.77 |
+15:40:09.0 |
HIP 33039 |
7.69 |
| 2026-02-23 00:00 |
06:52:28.84 |
+15:40:12.0 |
HIP 33039 |
7.92 |
| 2026-02-23 12:00 |
06:52:27.93 |
+15:40:14.9 |
HIP 33039 |
8.14 |
| 2026-02-24 00:00 |
06:52:27.02 |
+15:40:17.8 |
HIP 33039 |
8.36 |