| Parameter |
Value |
| Designation |
353P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-12-22T00:55:05.024640Z |
| Orbit solution date (soln_date, UTC) |
2025-09-09T12:42:56Z |
| Obs used |
126 |
| NEO |
- |
| M1 |
13.500 |
| K1 |
12.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-12-12.0000000 |
| e |
0.46877362 |
| q (au) |
2.212902 |
| a (au) |
4.165647 |
| i (deg) |
28.415165 |
| Ω (om, deg) |
121.588906 |
| ω (w, deg) |
230.495742 |
| M (ma, deg) |
189.468601 |
Magnitude
Scatter + Global Linear
$$
M_a = (16.866 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
16.866 |
| n |
2.000 |
| gf |
0.975 |
| gb |
-1.000 |
| k |
0.999 |
| δ90 |
9.948 |
| 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 |
22:17:51.08 |
-16:52:54.3 |
HIP 110219 |
26.92 |
| 2026-03-26 12:00 |
22:18:54.40 |
-16:51:02.8 |
HIP 110219 |
13.00 |
| 2026-03-27 00:00 |
22:19:57.72 |
-16:49:11.0 |
HIP 110219 |
8.90 |
| 2026-03-27 12:00 |
22:21:01.06 |
-16:47:19.0 |
HIP 110219 |
21.36 |
| 2026-03-28 00:00 |
22:22:04.40 |
-16:45:26.8 |
HIP 110401 |
24.73 |
| 2026-03-28 12:00 |
22:23:07.75 |
-16:43:34.4 |
HIP 110401 |
33.01 |
| 2026-03-29 00:00 |
22:24:11.10 |
-16:41:41.8 |
HIP 110778 |
34.37 |
| 2026-03-29 12:00 |
22:25:14.47 |
-16:39:49.0 |
HIP 110778 |
19.65 |
| 2026-03-30 00:00 |
22:26:17.84 |
-16:37:56.1 |
HIP 110778 |
7.66 |
| 2026-03-30 12:00 |
22:27:21.22 |
-16:36:03.0 |
HIP 110802 |
6.29 |
| 2026-03-31 00:00 |
22:28:24.61 |
-16:34:09.7 |
HIP 110802 |
21.56 |
| 2026-03-31 12:00 |
22:29:28.01 |
-16:32:16.4 |
HIP 111063 |
8.46 |
| 2026-04-01 00:00 |
22:30:31.42 |
-16:30:22.9 |
HIP 111063 |
8.15 |
| 2026-04-01 12:00 |
22:31:34.83 |
-16:28:29.3 |
HIP 111100 |
18.05 |
| 2026-04-02 00:00 |
22:32:38.25 |
-16:26:35.5 |
HIP 111100 |
32.08 |
| 2026-04-02 12:00 |
22:33:41.68 |
-16:24:41.7 |
HIP 111472 |
20.13 |
| 2026-04-03 00:00 |
22:34:45.11 |
-16:22:47.8 |
HIP 111472 |
6.77 |
| 2026-04-03 12:00 |
22:35:48.55 |
-16:20:53.9 |
HIP 111563 |
4.90 |
| 2026-04-04 00:00 |
22:36:52.01 |
-16:18:59.9 |
HIP 111691 |
10.07 |
| 2026-04-04 12:00 |
22:37:55.46 |
-16:17:05.8 |
HIP 111691 |
7.67 |
| 2026-04-05 00:00 |
22:38:58.93 |
-16:15:11.7 |
HIP 111780 |
14.87 |
| 2026-04-05 12:00 |
22:40:02.40 |
-16:13:17.6 |
HIP 111911 |
15.83 |
| 2026-04-06 00:00 |
22:41:05.88 |
-16:11:23.5 |
HIP 111911 |
19.62 |
| 2026-04-06 12:00 |
22:42:09.36 |
-16:09:29.4 |
HIP 112209 |
19.95 |
| 2026-04-07 00:00 |
22:43:12.86 |
-16:07:35.3 |
HIP 112209 |
4.72 |
| 2026-04-07 12:00 |
22:44:16.35 |
-16:05:41.2 |
HIP 112209 |
10.89 |
| 2026-04-08 00:00 |
22:45:19.86 |
-16:03:47.2 |
HIP 112209 |
26.22 |
| 2026-04-08 12:00 |
22:46:23.37 |
-16:01:53.2 |
HIP 112504 |
15.36 |
| 2026-04-09 00:00 |
22:47:26.88 |
-15:59:59.3 |
HIP 112504 |
8.92 |
| 2026-04-09 12:00 |
22:48:30.41 |
-15:58:05.4 |
HIP 112504 |
19.90 |
| 2026-04-10 00:00 |
22:49:33.93 |
-15:56:11.7 |
HIP 112755 |
23.89 |
| 2026-04-10 12:00 |
22:50:37.46 |
-15:54:18.1 |
HIP 112755 |
25.68 |
| 2026-04-11 00:00 |
22:51:41.00 |
-15:52:24.6 |
HIP 113050 |
32.44 |
| 2026-04-11 12:00 |
22:52:44.54 |
-15:50:31.2 |
HIP 113050 |
18.75 |
| 2026-04-12 00:00 |
22:53:48.08 |
-15:48:38.0 |
HIP 113050 |
11.21 |
| 2026-04-12 12:00 |
22:54:51.63 |
-15:46:44.9 |
HIP 113136 |
3.93 |
| 2026-04-13 00:00 |
22:55:55.18 |
-15:44:52.0 |
HIP 113136 |
18.83 |
| 2026-04-13 12:00 |
22:56:58.73 |
-15:42:59.3 |
HIP 113417 |
20.74 |
| 2026-04-14 00:00 |
22:58:02.29 |
-15:41:06.9 |
HIP 113417 |
13.40 |
| 2026-04-14 12:00 |
22:59:05.85 |
-15:39:14.6 |
HIP 113417 |
20.09 |
| 2026-04-15 00:00 |
23:00:09.41 |
-15:37:22.6 |
HIP 113685 |
24.78 |
| 2026-04-15 12:00 |
23:01:12.97 |
-15:35:30.8 |
HIP 113685 |
13.80 |
| 2026-04-16 00:00 |
23:02:16.53 |
-15:33:39.3 |
HIP 113685 |
15.58 |