| Parameter |
Value |
| Designation |
422P/Christensen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2006-05-27T22:01:25.478400Z |
| Orbit solution date (soln_date, UTC) |
2024-07-07T00:42:21Z |
| Obs used |
281 |
| NEO |
- |
| M1 |
7.100 |
| K1 |
18.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-06-05T07:45:40.032000Z |
| Discovery magnitude (MPC) |
18.60 R |
| Discovery observatory (MPC) |
Y00 · SONEAR Observatory, Oliveira |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-12-16.0000000 |
| e |
0.50606921 |
| q (au) |
3.092805 |
| a (au) |
6.261616 |
| i (deg) |
39.588451 |
| Ω (om, deg) |
36.088366 |
| ω (w, deg) |
305.989857 |
| M (ma, deg) |
173.555768 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.906 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.906 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2021-06-05 |
2022-11-29 |
+36.3090 |
-19.481 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
08:50:33.60 |
+61:17:47.9 |
HIP 43361 |
5.18 |
| 2026-03-26 12:00 |
08:50:24.22 |
+61:15:45.8 |
HIP 43361 |
3.33 |
| 2026-03-27 00:00 |
08:50:15.10 |
+61:13:42.8 |
HIP 43361 |
2.50 |
| 2026-03-27 12:00 |
08:50:06.25 |
+61:11:38.9 |
HIP 43361 |
3.52 |
| 2026-03-28 00:00 |
08:49:57.65 |
+61:09:34.1 |
HIP 43361 |
5.43 |
| 2026-03-28 12:00 |
08:49:49.30 |
+61:07:28.5 |
HIP 43361 |
7.58 |
| 2026-03-29 00:00 |
08:49:41.22 |
+61:05:21.9 |
HIP 43361 |
9.82 |
| 2026-03-29 12:00 |
08:49:33.39 |
+61:03:14.5 |
HIP 43361 |
12.10 |
| 2026-03-30 00:00 |
08:49:25.83 |
+61:01:06.3 |
HIP 43207 |
12.50 |
| 2026-03-30 12:00 |
08:49:18.51 |
+60:58:57.3 |
HIP 43207 |
10.48 |
| 2026-03-31 00:00 |
08:49:11.46 |
+60:56:47.5 |
HIP 43207 |
8.64 |
| 2026-03-31 12:00 |
08:49:04.66 |
+60:54:36.8 |
HIP 43207 |
7.13 |
| 2026-04-01 00:00 |
08:48:58.12 |
+60:52:25.4 |
HIP 43207 |
6.17 |
| 2026-04-01 12:00 |
08:48:51.83 |
+60:50:13.2 |
HIP 43207 |
6.04 |
| 2026-04-02 00:00 |
08:48:45.80 |
+60:48:00.3 |
HIP 43207 |
6.80 |
| 2026-04-02 12:00 |
08:48:40.02 |
+60:45:46.7 |
HIP 43207 |
8.21 |
| 2026-04-03 00:00 |
08:48:34.50 |
+60:43:32.3 |
HIP 43207 |
9.99 |
| 2026-04-03 12:00 |
08:48:29.22 |
+60:41:17.2 |
HIP 43207 |
11.98 |
| 2026-04-04 00:00 |
08:48:24.21 |
+60:39:01.4 |
HIP 43207 |
14.10 |
| 2026-04-04 12:00 |
08:48:19.44 |
+60:36:44.9 |
HIP 43207 |
16.29 |
| 2026-04-05 00:00 |
08:48:14.93 |
+60:34:27.8 |
HIP 43207 |
18.53 |
| 2026-04-05 12:00 |
08:48:10.66 |
+60:32:10.0 |
HIP 43207 |
20.81 |
| 2026-04-06 00:00 |
08:48:06.65 |
+60:29:51.5 |
HIP 43207 |
23.12 |
| 2026-04-06 12:00 |
08:48:02.89 |
+60:27:32.4 |
HIP 43207 |
25.44 |
| 2026-04-07 00:00 |
08:47:59.38 |
+60:25:12.7 |
HIP 43207 |
27.78 |
| 2026-04-07 12:00 |
08:47:56.11 |
+60:22:52.4 |
HIP 42958 |
28.91 |
| 2026-04-08 00:00 |
08:47:53.10 |
+60:20:31.5 |
HIP 42958 |
26.93 |
| 2026-04-08 12:00 |
08:47:50.33 |
+60:18:09.9 |
HIP 42958 |
25.03 |
| 2026-04-09 00:00 |
08:47:47.81 |
+60:15:47.9 |
HIP 42958 |
23.23 |
| 2026-04-09 12:00 |
08:47:45.53 |
+60:13:25.2 |
HIP 42958 |
21.57 |
| 2026-04-10 00:00 |
08:47:43.50 |
+60:11:02.0 |
HIP 42958 |
20.08 |
| 2026-04-10 12:00 |
08:47:41.71 |
+60:08:38.3 |
HIP 42958 |
18.80 |
| 2026-04-11 00:00 |
08:47:40.17 |
+60:06:14.0 |
HIP 42958 |
17.79 |
| 2026-04-11 12:00 |
08:47:38.87 |
+60:03:49.3 |
HIP 42958 |
17.08 |
| 2026-04-12 00:00 |
08:47:37.81 |
+60:01:24.0 |
HIP 42958 |
16.73 |
| 2026-04-12 12:00 |
08:47:36.99 |
+59:58:58.2 |
HIP 42958 |
16.76 |
| 2026-04-13 00:00 |
08:47:36.42 |
+59:56:32.0 |
HIP 42958 |
17.16 |
| 2026-04-13 12:00 |
08:47:36.08 |
+59:54:05.3 |
HIP 42958 |
17.92 |
| 2026-04-14 00:00 |
08:47:35.98 |
+59:51:38.1 |
HIP 42958 |
19.00 |
| 2026-04-14 12:00 |
08:47:36.12 |
+59:49:10.5 |
HIP 42958 |
20.35 |
| 2026-04-15 00:00 |
08:47:36.50 |
+59:46:42.4 |
HIP 42958 |
21.92 |
| 2026-04-15 12:00 |
08:47:37.11 |
+59:44:13.9 |
HIP 42958 |
23.67 |
| 2026-04-16 00:00 |
08:47:37.96 |
+59:41:45.0 |
HIP 42958 |
25.56 |