| 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
$$
M_a = (6.726 + 4.555\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.726 |
| n |
4.555 |
| gf |
0.943 |
| gb |
-0.999 |
| 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 |
+4.2939 |
-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) |
| 2026-05-12 00:00 |
06:34:48.63 |
+31:28:53.9 |
HIP 31414 |
4.01 |
| 2026-05-12 12:00 |
06:35:13.99 |
+31:28:34.9 |
HIP 31414 |
3.58 |
| 2026-05-13 00:00 |
06:35:39.45 |
+31:28:15.8 |
HIP 31520 |
4.28 |
| 2026-05-13 12:00 |
06:36:05.01 |
+31:27:56.5 |
HIP 31520 |
1.45 |
| 2026-05-14 00:00 |
06:36:30.67 |
+31:27:37.1 |
HIP 31520 |
6.77 |
| 2026-05-14 12:00 |
06:36:56.42 |
+31:27:17.5 |
HIP 31520 |
12.25 |
| 2026-05-15 00:00 |
06:37:22.27 |
+31:26:57.8 |
HIP 31643 |
15.69 |
| 2026-05-15 12:00 |
06:37:48.21 |
+31:26:38.0 |
HIP 31643 |
17.02 |
| 2026-05-16 00:00 |
06:38:14.24 |
+31:26:18.0 |
HIP 31643 |
19.88 |
| 2026-05-16 12:00 |
06:38:40.37 |
+31:25:57.9 |
HIP 31816 |
20.73 |
| 2026-05-17 00:00 |
06:39:06.59 |
+31:25:37.6 |
HIP 31816 |
20.34 |
| 2026-05-17 12:00 |
06:39:32.90 |
+31:25:17.1 |
HIP 31988 |
19.84 |
| 2026-05-18 00:00 |
06:39:59.30 |
+31:24:56.6 |
HIP 31988 |
14.29 |
| 2026-05-18 12:00 |
06:40:25.78 |
+31:24:35.8 |
HIP 31988 |
8.83 |
| 2026-05-19 00:00 |
06:40:52.36 |
+31:24:14.9 |
HIP 31988 |
3.99 |
| 2026-05-19 12:00 |
06:41:19.02 |
+31:23:53.9 |
HIP 31988 |
4.29 |
| 2026-05-20 00:00 |
06:41:45.76 |
+31:23:32.7 |
HIP 32083 |
6.14 |
| 2026-05-20 12:00 |
06:42:12.59 |
+31:23:11.4 |
HIP 32083 |
4.19 |
| 2026-05-21 00:00 |
06:42:39.50 |
+31:22:49.9 |
HIP 32083 |
7.96 |
| 2026-05-21 12:00 |
06:43:06.49 |
+31:22:28.2 |
HIP 32215 |
5.55 |
| 2026-05-22 00:00 |
06:43:33.57 |
+31:22:06.4 |
HIP 32215 |
0.40 |
| 2026-05-22 12:00 |
06:44:00.72 |
+31:21:44.4 |
HIP 32215 |
6.07 |
| 2026-05-23 00:00 |
06:44:27.95 |
+31:21:22.3 |
HIP 32215 |
11.89 |
| 2026-05-23 12:00 |
06:44:55.27 |
+31:21:00.0 |
HIP 32215 |
17.73 |
| 2026-05-24 00:00 |
06:45:22.65 |
+31:20:37.6 |
HIP 32482 |
17.78 |
| 2026-05-24 12:00 |
06:45:50.12 |
+31:20:15.0 |
HIP 32482 |
11.95 |
| 2026-05-25 00:00 |
06:46:17.66 |
+31:19:52.2 |
HIP 32482 |
6.20 |
| 2026-05-25 12:00 |
06:46:45.27 |
+31:19:29.3 |
HIP 32482 |
1.87 |
| 2026-05-26 00:00 |
06:47:12.96 |
+31:19:06.2 |
HIP 32482 |
6.21 |
| 2026-05-26 12:00 |
06:47:40.71 |
+31:18:42.9 |
HIP 32482 |
12.01 |
| 2026-05-27 00:00 |
06:48:08.55 |
+31:18:19.5 |
HIP 32651 |
7.04 |
| 2026-05-27 12:00 |
06:48:36.45 |
+31:17:55.9 |
HIP 32651 |
2.04 |
| 2026-05-28 00:00 |
06:49:04.42 |
+31:17:32.1 |
HIP 32651 |
5.50 |
| 2026-05-28 12:00 |
06:49:32.46 |
+31:17:08.2 |
HIP 32651 |
11.33 |
| 2026-05-29 00:00 |
06:50:00.57 |
+31:16:44.1 |
HIP 32651 |
17.30 |
| 2026-05-29 12:00 |
06:50:28.75 |
+31:16:19.8 |
HIP 32651 |
23.31 |
| 2026-05-30 00:00 |
06:50:56.99 |
+31:15:55.4 |
HIP 32651 |
29.34 |
| 2026-05-30 12:00 |
06:51:25.30 |
+31:15:30.7 |
HIP 33049 |
24.45 |
| 2026-05-31 00:00 |
06:51:53.68 |
+31:15:06.0 |
HIP 33049 |
19.62 |
| 2026-05-31 12:00 |
06:52:22.12 |
+31:14:41.0 |
HIP 33049 |
15.67 |
| 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 |