| Parameter |
Value |
| Designation |
495P/Christensen |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2025-10-25T06:46:55.292160Z |
| Orbit solution date (soln_date, UTC) |
2026-06-09T11:12:51Z |
| Obs used |
118 |
| NEO |
- |
| M1 |
13.700 |
| K1 |
7.500 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2024-09-08T07:05:23.683200Z |
| Discovery magnitude (MPC) |
21.04 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-02-08.0000000 |
| e |
0.27115512 |
| q (au) |
3.462563 |
| a (au) |
4.750755 |
| i (deg) |
26.355591 |
| Ω (om, deg) |
291.623353 |
| ω (w, deg) |
141.487838 |
| M (ma, deg) |
196.258045 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.873 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.873 |
| n |
2.000 |
| gf |
0.997 |
| gb |
-0.721 |
| k |
0.800 |
| 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) |
| 2026-09-25 00:00 |
09:09:40.11 |
+10:04:02.0 |
HIP 44978 |
18.23 |
| 2026-09-25 12:00 |
09:10:07.85 |
+09:59:48.5 |
HIP 44978 |
15.14 |
| 2026-09-26 00:00 |
09:10:35.49 |
+09:55:34.8 |
HIP 44978 |
15.95 |
| 2026-09-26 12:00 |
09:11:03.00 |
+09:51:20.9 |
HIP 44978 |
20.18 |
| 2026-09-27 00:00 |
09:11:30.40 |
+09:47:06.8 |
HIP 45197 |
17.29 |
| 2026-09-27 12:00 |
09:11:57.69 |
+09:42:52.5 |
HIP 45197 |
13.53 |
| 2026-09-28 00:00 |
09:12:24.86 |
+09:38:38.1 |
HIP 45197 |
13.91 |
| 2026-09-28 12:00 |
09:12:51.91 |
+09:34:23.5 |
HIP 45197 |
18.16 |
| 2026-09-29 00:00 |
09:13:18.84 |
+09:30:08.7 |
HIP 45199 |
18.01 |
| 2026-09-29 12:00 |
09:13:45.65 |
+09:25:53.7 |
HIP 45199 |
19.79 |
| 2026-09-30 00:00 |
09:14:12.35 |
+09:21:38.6 |
HIP 45199 |
24.11 |
| 2026-09-30 12:00 |
09:14:38.92 |
+09:17:23.4 |
HIP 45409 |
29.42 |
| 2026-10-01 00:00 |
09:15:05.37 |
+09:13:07.9 |
HIP 45409 |
32.49 |
| 2026-10-01 12:00 |
09:15:31.70 |
+09:08:52.4 |
HIP 45409 |
36.98 |
| 2026-10-02 00:00 |
09:15:57.90 |
+09:04:36.7 |
HIP 45608 |
30.17 |
| 2026-10-02 12:00 |
09:16:23.98 |
+09:00:20.8 |
HIP 45608 |
22.54 |
| 2026-10-03 00:00 |
09:16:49.94 |
+08:56:04.8 |
HIP 45608 |
15.03 |
| 2026-10-03 12:00 |
09:17:15.77 |
+08:51:48.7 |
HIP 45608 |
7.91 |
| 2026-10-04 00:00 |
09:17:41.47 |
+08:47:32.4 |
HIP 45608 |
4.16 |
| 2026-10-04 12:00 |
09:18:07.05 |
+08:43:16.1 |
HIP 45608 |
9.43 |
| 2026-10-05 00:00 |
09:18:32.50 |
+08:38:59.6 |
HIP 45608 |
16.62 |
| 2026-10-05 12:00 |
09:18:57.81 |
+08:34:43.0 |
HIP 45634 |
23.84 |
| 2026-10-06 00:00 |
09:19:23.00 |
+08:30:26.3 |
HIP 45772 |
21.46 |
| 2026-10-06 12:00 |
09:19:48.05 |
+08:26:09.4 |
HIP 45772 |
15.49 |
| 2026-10-07 00:00 |
09:20:12.97 |
+08:21:52.6 |
HIP 45851 |
11.36 |
| 2026-10-07 12:00 |
09:20:37.76 |
+08:17:35.6 |
HIP 45851 |
3.98 |
| 2026-10-08 00:00 |
09:21:02.41 |
+08:13:18.5 |
HIP 45851 |
3.80 |
| 2026-10-08 12:00 |
09:21:26.93 |
+08:09:01.3 |
HIP 45912 |
5.26 |
| 2026-10-09 00:00 |
09:21:51.31 |
+08:04:44.1 |
HIP 45912 |
8.29 |
| 2026-10-09 12:00 |
09:22:15.55 |
+08:00:26.9 |
HIP 45912 |
14.79 |
| 2026-10-10 00:00 |
09:22:39.66 |
+07:56:09.5 |
HIP 46053 |
18.17 |
| 2026-10-10 12:00 |
09:23:03.62 |
+07:51:52.1 |
HIP 46053 |
11.09 |
| 2026-10-11 00:00 |
09:23:27.44 |
+07:47:34.7 |
HIP 46053 |
4.78 |
| 2026-10-11 12:00 |
09:23:51.13 |
+07:43:17.2 |
HIP 46053 |
5.37 |
| 2026-10-12 00:00 |
09:24:14.66 |
+07:38:59.7 |
HIP 46053 |
11.82 |
| 2026-10-12 12:00 |
09:24:38.06 |
+07:34:42.1 |
HIP 46053 |
18.82 |
| 2026-10-13 00:00 |
09:25:01.31 |
+07:30:24.6 |
HIP 46303 |
25.23 |
| 2026-10-13 12:00 |
09:25:24.42 |
+07:26:07.0 |
HIP 46303 |
22.64 |
| 2026-10-14 00:00 |
09:25:47.37 |
+07:21:49.4 |
HIP 46303 |
22.17 |
| 2026-10-14 12:00 |
09:26:10.19 |
+07:17:31.8 |
HIP 46400 |
23.54 |
| 2026-10-15 00:00 |
09:26:32.85 |
+07:13:14.2 |
HIP 46400 |
19.59 |
| 2026-10-15 12:00 |
09:26:55.37 |
+07:08:56.5 |
HIP 46400 |
17.72 |
| 2026-10-16 00:00 |
09:27:17.73 |
+07:04:38.9 |
HIP 46447 |
16.89 |