| Parameter |
Value |
| Designation |
C/2005 O2 (Christensen) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2005-09-08T10:41:22.672320Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:51Z |
| Obs used |
126 |
| NEO |
- |
| M1 |
5.200 |
| K1 |
20.000 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2005-09-25.0000000 |
| e |
0.85937661 |
| q (au) |
3.333576 |
| a (au) |
23.705702 |
| i (deg) |
148.892051 |
| Ω (om, deg) |
280.771395 |
| ω (w, deg) |
263.833891 |
| M (ma, deg) |
0.141366 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.164 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.164 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-03-26 00:00 |
15:16:34.44 |
+10:51:10.6 |
HIP 74718 |
5.93 |
| 2026-03-26 12:00 |
15:16:31.50 |
+10:51:43.6 |
HIP 74718 |
5.43 |
| 2026-03-27 00:00 |
15:16:28.54 |
+10:52:16.5 |
HIP 74718 |
5.05 |
| 2026-03-27 12:00 |
15:16:25.56 |
+10:52:49.3 |
HIP 74718 |
4.81 |
| 2026-03-28 00:00 |
15:16:22.54 |
+10:53:22.1 |
HIP 74718 |
4.72 |
| 2026-03-28 12:00 |
15:16:19.51 |
+10:53:54.8 |
HIP 74718 |
4.82 |
| 2026-03-29 00:00 |
15:16:16.45 |
+10:54:27.3 |
HIP 74718 |
5.07 |
| 2026-03-29 12:00 |
15:16:13.37 |
+10:54:59.8 |
HIP 74718 |
5.48 |
| 2026-03-30 00:00 |
15:16:10.26 |
+10:55:32.2 |
HIP 74718 |
5.99 |
| 2026-03-30 12:00 |
15:16:07.13 |
+10:56:04.5 |
HIP 74718 |
6.60 |
| 2026-03-31 00:00 |
15:16:03.97 |
+10:56:36.7 |
HIP 74718 |
7.29 |
| 2026-03-31 12:00 |
15:16:00.80 |
+10:57:08.7 |
HIP 74718 |
8.02 |
| 2026-04-01 00:00 |
15:15:57.60 |
+10:57:40.7 |
HIP 74718 |
8.79 |
| 2026-04-01 12:00 |
15:15:54.37 |
+10:58:12.6 |
HIP 74718 |
9.60 |
| 2026-04-02 00:00 |
15:15:51.13 |
+10:58:44.3 |
HIP 74718 |
10.43 |
| 2026-04-02 12:00 |
15:15:47.86 |
+10:59:16.0 |
HIP 74718 |
11.29 |
| 2026-04-03 00:00 |
15:15:44.57 |
+10:59:47.5 |
HIP 74718 |
12.16 |
| 2026-04-03 12:00 |
15:15:41.26 |
+11:00:18.9 |
HIP 74718 |
13.04 |
| 2026-04-04 00:00 |
15:15:37.93 |
+11:00:50.2 |
HIP 74718 |
13.94 |
| 2026-04-04 12:00 |
15:15:34.58 |
+11:01:21.3 |
HIP 74718 |
14.84 |
| 2026-04-05 00:00 |
15:15:31.21 |
+11:01:52.4 |
HIP 74718 |
15.76 |
| 2026-04-05 12:00 |
15:15:27.81 |
+11:02:23.3 |
HIP 74718 |
16.69 |
| 2026-04-06 00:00 |
15:15:24.40 |
+11:02:54.1 |
HIP 74718 |
17.62 |
| 2026-04-06 12:00 |
15:15:20.96 |
+11:03:24.7 |
HIP 74718 |
18.56 |
| 2026-04-07 00:00 |
15:15:17.51 |
+11:03:55.2 |
HIP 74718 |
19.51 |
| 2026-04-07 12:00 |
15:15:14.03 |
+11:04:25.6 |
HIP 74589 |
19.73 |
| 2026-04-08 00:00 |
15:15:10.54 |
+11:04:55.9 |
HIP 74589 |
19.65 |
| 2026-04-08 12:00 |
15:15:07.02 |
+11:05:26.0 |
HIP 74589 |
19.62 |
| 2026-04-09 00:00 |
15:15:03.49 |
+11:05:55.9 |
HIP 74589 |
19.64 |
| 2026-04-09 12:00 |
15:14:59.94 |
+11:06:25.7 |
HIP 74589 |
19.70 |
| 2026-04-10 00:00 |
15:14:56.37 |
+11:06:55.4 |
HIP 74589 |
19.81 |
| 2026-04-10 12:00 |
15:14:52.78 |
+11:07:24.9 |
HIP 74589 |
19.97 |
| 2026-04-11 00:00 |
15:14:49.18 |
+11:07:54.3 |
HIP 74589 |
20.17 |
| 2026-04-11 12:00 |
15:14:45.55 |
+11:08:23.5 |
HIP 74589 |
20.41 |
| 2026-04-12 00:00 |
15:14:41.91 |
+11:08:52.6 |
HIP 74589 |
20.70 |
| 2026-04-12 12:00 |
15:14:38.25 |
+11:09:21.5 |
HIP 74589 |
21.04 |
| 2026-04-13 00:00 |
15:14:34.58 |
+11:09:50.3 |
HIP 74608 |
21.15 |
| 2026-04-13 12:00 |
15:14:30.88 |
+11:10:18.8 |
HIP 74608 |
20.75 |
| 2026-04-14 00:00 |
15:14:27.18 |
+11:10:47.3 |
HIP 74608 |
20.40 |
| 2026-04-14 12:00 |
15:14:23.45 |
+11:11:15.5 |
HIP 74608 |
20.10 |
| 2026-04-15 00:00 |
15:14:19.71 |
+11:11:43.6 |
HIP 74608 |
19.84 |
| 2026-04-15 12:00 |
15:14:15.95 |
+11:12:11.5 |
HIP 74608 |
19.65 |
| 2026-04-16 00:00 |
15:14:12.18 |
+11:12:39.2 |
HIP 74608 |
19.51 |