| Parameter |
Value |
| Designation |
262P/McNaught-Russell |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2012-12-04T11:01:48.411840Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:28:09Z |
| Obs used |
1339 |
| NEO |
Yes |
| M1 |
14.700 |
| K1 |
6.500 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2011-12-24.0000000 |
| e |
0.81540093 |
| q (au) |
1.280260 |
| a (au) |
6.935353 |
| i (deg) |
29.079418 |
| Ω (om, deg) |
218.014306 |
| ω (w, deg) |
171.169762 |
| M (ma, deg) |
341.303779 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.572 + 3.736\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.572 |
| n |
3.736 |
| gf |
0.800 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
1.000 |
| 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 |
| 2012-05-29 |
2012-09-20 |
-8.5325 |
+2.913 |
| 2012-09-20 |
2012-12-04 |
+11.6281 |
-1.021 |
| 2012-12-05 |
2013-04-22 |
-6.0909 |
-0.588 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
14:48:04.58 |
-11:13:46.2 |
HIP 72299 |
16.71 |
| 2026-06-01 12:00 |
14:47:55.42 |
-11:12:57.2 |
HIP 72299 |
15.29 |
| 2026-06-02 00:00 |
14:47:46.32 |
-11:12:08.5 |
HIP 72299 |
14.13 |
| 2026-06-02 12:00 |
14:47:37.26 |
-11:11:20.2 |
HIP 72299 |
13.31 |
| 2026-06-03 00:00 |
14:47:28.26 |
-11:10:32.2 |
HIP 72299 |
12.87 |
| 2026-06-03 12:00 |
14:47:19.31 |
-11:09:44.6 |
HIP 72299 |
12.85 |
| 2026-06-04 00:00 |
14:47:10.41 |
-11:08:57.3 |
HIP 72299 |
13.25 |
| 2026-06-04 12:00 |
14:47:01.57 |
-11:08:10.4 |
HIP 72299 |
14.01 |
| 2026-06-05 00:00 |
14:46:52.78 |
-11:07:23.8 |
HIP 72299 |
15.08 |
| 2026-06-05 12:00 |
14:46:44.06 |
-11:06:37.6 |
HIP 72299 |
16.40 |
| 2026-06-06 00:00 |
14:46:35.38 |
-11:05:51.7 |
HIP 72299 |
17.89 |
| 2026-06-06 12:00 |
14:46:26.77 |
-11:05:06.2 |
HIP 72299 |
19.53 |
| 2026-06-07 00:00 |
14:46:18.21 |
-11:04:21.1 |
HIP 72299 |
21.26 |
| 2026-06-07 12:00 |
14:46:09.72 |
-11:03:36.3 |
HIP 72168 |
22.98 |
| 2026-06-08 00:00 |
14:46:01.28 |
-11:02:51.9 |
HIP 72168 |
23.11 |
| 2026-06-08 12:00 |
14:45:52.91 |
-11:02:08.0 |
HIP 72168 |
23.45 |
| 2026-06-09 00:00 |
14:45:44.60 |
-11:01:24.4 |
HIP 72168 |
23.97 |
| 2026-06-09 12:00 |
14:45:36.35 |
-11:00:41.1 |
HIP 72168 |
24.67 |
| 2026-06-10 00:00 |
14:45:28.16 |
-10:59:58.3 |
HIP 72168 |
25.52 |
| 2026-06-10 12:00 |
14:45:20.04 |
-10:59:15.9 |
HIP 72168 |
26.50 |
| 2026-06-11 00:00 |
14:45:11.99 |
-10:58:33.9 |
HIP 72168 |
27.61 |
| 2026-06-11 12:00 |
14:45:04.00 |
-10:57:52.2 |
HIP 72168 |
28.81 |
| 2026-06-12 00:00 |
14:44:56.07 |
-10:57:11.0 |
HIP 72168 |
30.09 |
| 2026-06-12 12:00 |
14:44:48.22 |
-10:56:30.2 |
HIP 71982 |
30.42 |
| 2026-06-13 00:00 |
14:44:40.43 |
-10:55:49.8 |
HIP 71982 |
28.59 |
| 2026-06-13 12:00 |
14:44:32.72 |
-10:55:09.8 |
HIP 71982 |
26.81 |
| 2026-06-14 00:00 |
14:44:25.07 |
-10:54:30.3 |
HIP 71982 |
25.08 |
| 2026-06-14 12:00 |
14:44:17.49 |
-10:53:51.1 |
HIP 71982 |
23.40 |
| 2026-06-15 00:00 |
14:44:09.99 |
-10:53:12.4 |
HIP 71982 |
21.79 |
| 2026-06-15 12:00 |
14:44:02.56 |
-10:52:34.1 |
HIP 71982 |
20.26 |
| 2026-06-16 00:00 |
14:43:55.20 |
-10:51:56.3 |
HIP 71982 |
18.81 |
| 2026-06-16 12:00 |
14:43:47.91 |
-10:51:18.9 |
HIP 71982 |
17.47 |
| 2026-06-17 00:00 |
14:43:40.70 |
-10:50:41.9 |
HIP 71982 |
16.25 |
| 2026-06-17 12:00 |
14:43:33.57 |
-10:50:05.3 |
HIP 71982 |
15.18 |
| 2026-06-18 00:00 |
14:43:26.51 |
-10:49:29.2 |
HIP 71982 |
14.28 |
| 2026-06-18 12:00 |
14:43:19.52 |
-10:48:53.6 |
HIP 71982 |
13.57 |
| 2026-06-19 00:00 |
14:43:12.61 |
-10:48:18.4 |
HIP 71982 |
13.09 |
| 2026-06-19 12:00 |
14:43:05.79 |
-10:47:43.6 |
HIP 71982 |
12.84 |
| 2026-06-20 00:00 |
14:42:59.03 |
-10:47:09.3 |
HIP 71982 |
12.84 |
| 2026-06-20 12:00 |
14:42:52.36 |
-10:46:35.5 |
HIP 71982 |
13.07 |
| 2026-06-21 00:00 |
14:42:45.77 |
-10:46:02.1 |
HIP 71982 |
13.52 |
| 2026-06-21 12:00 |
14:42:39.25 |
-10:45:29.1 |
HIP 71982 |
14.15 |
| 2026-06-22 00:00 |
14:42:32.82 |
-10:44:56.6 |
HIP 71982 |
14.94 |