| Parameter |
Value |
| Designation |
164P/Christensen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2018-05-31T09:59:42.835200Z |
| Orbit solution date (soln_date, UTC) |
2026-03-31T14:13:45Z |
| Obs used |
1726 |
| NEO |
- |
| M1 |
14.300 |
| K1 |
4.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2018-02-10.0000000 |
| e |
0.53972829 |
| q (au) |
1.685232 |
| a (au) |
3.661385 |
| i (deg) |
16.252523 |
| Ω (om, deg) |
88.307288 |
| ω (w, deg) |
325.934090 |
| M (ma, deg) |
344.466480 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.023 + 2.918\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.023 |
| n |
2.918 |
| gf |
1.000 |
| gb |
-0.709 |
| k |
0.984 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
10:36:07.91 |
+31:58:10.0 |
HIP 51840 |
14.15 |
| 2026-03-26 12:00 |
10:35:50.38 |
+31:57:27.6 |
HIP 51840 |
11.69 |
| 2026-03-27 00:00 |
10:35:33.19 |
+31:56:41.9 |
HIP 51840 |
10.03 |
| 2026-03-27 12:00 |
10:35:16.35 |
+31:55:53.0 |
HIP 51840 |
9.55 |
| 2026-03-28 00:00 |
10:34:59.84 |
+31:55:01.0 |
HIP 51840 |
10.33 |
| 2026-03-28 12:00 |
10:34:43.68 |
+31:54:05.8 |
HIP 51840 |
12.10 |
| 2026-03-29 00:00 |
10:34:27.86 |
+31:53:07.6 |
HIP 51758 |
12.31 |
| 2026-03-29 12:00 |
10:34:12.38 |
+31:52:06.2 |
HIP 51758 |
11.92 |
| 2026-03-30 00:00 |
10:33:57.26 |
+31:51:01.9 |
HIP 51758 |
12.43 |
| 2026-03-30 12:00 |
10:33:42.48 |
+31:49:54.5 |
HIP 51758 |
13.69 |
| 2026-03-31 00:00 |
10:33:28.05 |
+31:48:44.2 |
HIP 51758 |
15.48 |
| 2026-03-31 12:00 |
10:33:13.97 |
+31:47:31.0 |
HIP 51758 |
17.62 |
| 2026-04-01 00:00 |
10:33:00.25 |
+31:46:14.9 |
HIP 51758 |
19.98 |
| 2026-04-01 12:00 |
10:32:46.87 |
+31:44:56.0 |
HIP 51606 |
19.94 |
| 2026-04-02 00:00 |
10:32:33.85 |
+31:43:34.2 |
HIP 51606 |
18.27 |
| 2026-04-02 12:00 |
10:32:21.18 |
+31:42:09.7 |
HIP 51606 |
16.94 |
| 2026-04-03 00:00 |
10:32:08.87 |
+31:40:42.4 |
HIP 51606 |
16.02 |
| 2026-04-03 12:00 |
10:31:56.90 |
+31:39:12.4 |
HIP 51606 |
15.57 |
| 2026-04-04 00:00 |
10:31:45.30 |
+31:37:39.8 |
HIP 51606 |
15.58 |
| 2026-04-04 12:00 |
10:31:34.04 |
+31:36:04.5 |
HIP 51606 |
16.05 |
| 2026-04-05 00:00 |
10:31:23.15 |
+31:34:26.5 |
HIP 51606 |
16.91 |
| 2026-04-05 12:00 |
10:31:12.60 |
+31:32:46.1 |
HIP 51606 |
18.09 |
| 2026-04-06 00:00 |
10:31:02.41 |
+31:31:03.1 |
HIP 51606 |
19.52 |
| 2026-04-06 12:00 |
10:30:52.58 |
+31:29:17.5 |
HIP 51606 |
21.14 |
| 2026-04-07 00:00 |
10:30:43.10 |
+31:27:29.5 |
HIP 51606 |
22.89 |
| 2026-04-07 12:00 |
10:30:33.98 |
+31:25:39.1 |
HIP 51606 |
24.74 |
| 2026-04-08 00:00 |
10:30:25.21 |
+31:23:46.2 |
HIP 51543 |
26.43 |
| 2026-04-08 12:00 |
10:30:16.80 |
+31:21:51.0 |
HIP 51543 |
26.08 |
| 2026-04-09 00:00 |
10:30:08.73 |
+31:19:53.4 |
HIP 51543 |
25.92 |
| 2026-04-09 12:00 |
10:30:01.03 |
+31:17:53.5 |
HIP 51543 |
25.93 |
| 2026-04-10 00:00 |
10:29:53.67 |
+31:15:51.3 |
HIP 51543 |
26.12 |
| 2026-04-10 12:00 |
10:29:46.67 |
+31:13:46.8 |
HIP 51543 |
26.47 |
| 2026-04-11 00:00 |
10:29:40.02 |
+31:11:40.2 |
HIP 51543 |
26.98 |
| 2026-04-11 12:00 |
10:29:33.73 |
+31:09:31.3 |
HIP 51543 |
27.64 |
| 2026-04-12 00:00 |
10:29:27.78 |
+31:07:20.3 |
HIP 51543 |
28.42 |
| 2026-04-12 12:00 |
10:29:22.18 |
+31:05:07.1 |
HIP 51543 |
29.33 |
| 2026-04-13 00:00 |
10:29:16.94 |
+31:02:51.8 |
HIP 51543 |
30.34 |
| 2026-04-13 12:00 |
10:29:12.04 |
+31:00:34.5 |
HIP 51543 |
31.45 |
| 2026-04-14 00:00 |
10:29:07.49 |
+30:58:15.1 |
HIP 51543 |
32.65 |
| 2026-04-14 12:00 |
10:29:03.28 |
+30:55:53.6 |
HIP 51543 |
33.93 |
| 2026-04-15 00:00 |
10:28:59.43 |
+30:53:30.2 |
HIP 51543 |
35.28 |
| 2026-04-15 12:00 |
10:28:55.92 |
+30:51:04.8 |
HIP 51543 |
36.70 |
| 2026-04-16 00:00 |
10:28:52.75 |
+30:48:37.5 |
HIP 51543 |
38.17 |