| Parameter |
Value |
| Designation |
246P/NEAT |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2013-01-28T15:13:27.269760Z |
| Orbit solution date (soln_date, UTC) |
2024-12-26T20:12:42Z |
| Obs used |
4914 |
| NEO |
- |
| M1 |
5.900 |
| K1 |
14.750 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-05-21.0000000 |
| e |
0.28504446 |
| q (au) |
2.879720 |
| a (au) |
4.027832 |
| i (deg) |
15.971716 |
| Ω (om, deg) |
78.780536 |
| ω (w, deg) |
176.171718 |
| M (ma, deg) |
13.700320 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.725 + 4.555\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.725 |
| n |
4.555 |
| gf |
0.995 |
| gb |
-0.502 |
| 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 |
| 2018-12-16 |
2020-04-22 |
-9.1189 |
+4.406 |
| 2020-04-22 |
2021-02-25 |
+4.2940 |
-2.300 |
| 2021-02-25 |
2019-09-03 |
+3.5698 |
-2.201 |
| 2019-09-03 |
2024-12-07 |
+8.2838 |
-4.696 |
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 |
06:52:50.62 |
+31:14:15.9 |
HIP 33049 |
13.42 |
| 2026-06-01 12:00 |
06:53:19.19 |
+31:13:50.5 |
HIP 33134 |
10.42 |
| 2026-06-02 00:00 |
06:53:47.82 |
+31:13:25.1 |
HIP 33134 |
6.42 |
| 2026-06-02 12:00 |
06:54:16.51 |
+31:12:59.4 |
HIP 33134 |
7.02 |
| 2026-06-03 00:00 |
06:54:45.26 |
+31:12:33.6 |
HIP 33134 |
11.54 |
| 2026-06-03 12:00 |
06:55:14.08 |
+31:12:07.5 |
HIP 33272 |
16.23 |
| 2026-06-04 00:00 |
06:55:42.95 |
+31:11:41.4 |
HIP 33272 |
16.84 |
| 2026-06-04 12:00 |
06:56:11.88 |
+31:11:15.0 |
HIP 33393 |
13.76 |
| 2026-06-05 00:00 |
06:56:40.87 |
+31:10:48.4 |
HIP 33393 |
12.34 |
| 2026-06-05 12:00 |
06:57:09.92 |
+31:10:21.7 |
HIP 33393 |
13.87 |
| 2026-06-06 00:00 |
06:57:39.03 |
+31:09:54.8 |
HIP 33393 |
17.62 |
| 2026-06-06 12:00 |
06:58:08.19 |
+31:09:27.7 |
HIP 33393 |
22.51 |
| 2026-06-07 00:00 |
06:58:37.41 |
+31:09:00.4 |
HIP 33393 |
27.96 |
| 2026-06-07 12:00 |
06:59:06.68 |
+31:08:33.0 |
HIP 33678 |
33.51 |
| 2026-06-08 00:00 |
06:59:36.00 |
+31:08:05.3 |
HIP 33678 |
32.90 |
| 2026-06-08 12:00 |
07:00:05.38 |
+31:07:37.5 |
HIP 33916 |
29.22 |
| 2026-06-09 00:00 |
07:00:34.81 |
+31:07:09.5 |
HIP 33916 |
23.28 |
| 2026-06-09 12:00 |
07:01:04.30 |
+31:06:41.3 |
HIP 33916 |
17.60 |
| 2026-06-10 00:00 |
07:01:33.83 |
+31:06:13.0 |
HIP 33916 |
12.53 |
| 2026-06-10 12:00 |
07:02:03.42 |
+31:05:44.4 |
HIP 33916 |
9.19 |
| 2026-06-11 00:00 |
07:02:33.06 |
+31:05:15.7 |
HIP 33916 |
9.62 |
| 2026-06-11 12:00 |
07:03:02.74 |
+31:04:46.8 |
HIP 33916 |
13.49 |
| 2026-06-12 00:00 |
07:03:32.47 |
+31:04:17.7 |
HIP 33916 |
18.78 |
| 2026-06-12 12:00 |
07:04:02.25 |
+31:03:48.4 |
HIP 33945 |
24.32 |
| 2026-06-13 00:00 |
07:04:32.08 |
+31:03:19.0 |
HIP 34229 |
25.88 |
| 2026-06-13 12:00 |
07:05:01.96 |
+31:02:49.3 |
HIP 34229 |
22.92 |
| 2026-06-14 00:00 |
07:05:31.87 |
+31:02:19.5 |
HIP 34229 |
21.52 |
| 2026-06-14 12:00 |
07:06:01.84 |
+31:01:49.5 |
HIP 34229 |
21.99 |
| 2026-06-15 00:00 |
07:06:31.84 |
+31:01:19.3 |
HIP 34229 |
24.23 |
| 2026-06-15 12:00 |
07:07:01.89 |
+31:00:49.0 |
HIP 34229 |
27.81 |
| 2026-06-16 00:00 |
07:07:31.98 |
+31:00:18.4 |
HIP 34456 |
30.63 |
| 2026-06-16 12:00 |
07:08:02.11 |
+30:59:47.7 |
HIP 34456 |
28.96 |
| 2026-06-17 00:00 |
07:08:32.28 |
+30:59:16.8 |
HIP 34456 |
28.69 |
| 2026-06-17 12:00 |
07:09:02.49 |
+30:58:45.8 |
HIP 34456 |
29.86 |
| 2026-06-18 00:00 |
07:09:32.74 |
+30:58:14.6 |
HIP 34456 |
32.31 |
| 2026-06-18 12:00 |
07:10:03.03 |
+30:57:43.1 |
HIP 34745 |
32.13 |
| 2026-06-19 00:00 |
07:10:33.35 |
+30:57:11.6 |
HIP 34745 |
28.95 |
| 2026-06-19 12:00 |
07:11:03.70 |
+30:56:39.8 |
HIP 34745 |
26.99 |
| 2026-06-20 00:00 |
07:11:34.10 |
+30:56:07.9 |
HIP 34883 |
23.54 |
| 2026-06-20 12:00 |
07:12:04.52 |
+30:55:35.8 |
HIP 34883 |
18.85 |
| 2026-06-21 00:00 |
07:12:34.98 |
+30:55:03.5 |
HIP 34883 |
15.55 |
| 2026-06-21 12:00 |
07:13:05.47 |
+30:54:31.1 |
HIP 34883 |
14.64 |
| 2026-06-22 00:00 |
07:13:35.99 |
+30:53:58.5 |
HIP 34883 |
16.52 |