| Parameter |
Value |
| Designation |
P/2013 YG46 (Spacewatch) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-01-19T12:53:16.437120Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:44Z |
| Obs used |
55 |
| NEO |
- |
| M1 |
10.600 |
| K1 |
10.000 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2014-01-29.0000000 |
| e |
0.45164645 |
| q (au) |
1.815243 |
| a (au) |
3.310351 |
| i (deg) |
8.219141 |
| Ω (om, deg) |
56.868085 |
| ω (w, deg) |
232.796581 |
| M (ma, deg) |
182.197613 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
08:37:58.92 |
+24:28:39.1 |
HIP 42423 |
14.61 |
| 2026-07-29 12:00 |
08:38:28.14 |
+24:26:53.9 |
HIP 42423 |
7.87 |
| 2026-07-30 00:00 |
08:38:57.35 |
+24:25:08.6 |
HIP 42423 |
2.25 |
| 2026-07-30 12:00 |
08:39:26.57 |
+24:23:23.2 |
HIP 42423 |
6.54 |
| 2026-07-31 00:00 |
08:39:55.77 |
+24:21:37.6 |
HIP 42423 |
13.23 |
| 2026-07-31 12:00 |
08:40:24.98 |
+24:19:51.9 |
HIP 42423 |
20.05 |
| 2026-08-01 00:00 |
08:40:54.18 |
+24:18:06.1 |
HIP 42684 |
15.38 |
| 2026-08-01 12:00 |
08:41:23.37 |
+24:16:20.2 |
HIP 42684 |
9.79 |
| 2026-08-02 00:00 |
08:41:52.56 |
+24:14:34.2 |
HIP 42684 |
7.05 |
| 2026-08-02 12:00 |
08:42:21.74 |
+24:12:48.0 |
HIP 42684 |
9.92 |
| 2026-08-03 00:00 |
08:42:50.92 |
+24:11:01.8 |
HIP 42783 |
3.90 |
| 2026-08-03 12:00 |
08:43:20.08 |
+24:09:15.4 |
HIP 42783 |
4.07 |
| 2026-08-04 00:00 |
08:43:49.25 |
+24:07:29.0 |
HIP 42816 |
9.31 |
| 2026-08-04 12:00 |
08:44:18.40 |
+24:05:42.4 |
HIP 42816 |
13.13 |
| 2026-08-05 00:00 |
08:44:47.54 |
+24:03:55.8 |
HIP 42816 |
18.78 |
| 2026-08-05 12:00 |
08:45:16.68 |
+24:02:09.1 |
HIP 43053 |
17.34 |
| 2026-08-06 00:00 |
08:45:45.80 |
+24:00:22.2 |
HIP 43053 |
11.28 |
| 2026-08-06 12:00 |
08:46:14.91 |
+23:58:35.3 |
HIP 43053 |
7.00 |
| 2026-08-07 00:00 |
08:46:44.02 |
+23:56:48.3 |
HIP 43053 |
8.10 |
| 2026-08-07 12:00 |
08:47:13.11 |
+23:55:01.2 |
HIP 43053 |
13.30 |
| 2026-08-08 00:00 |
08:47:42.19 |
+23:53:14.1 |
HIP 43242 |
18.89 |
| 2026-08-08 12:00 |
08:48:11.25 |
+23:51:26.8 |
HIP 43242 |
17.18 |
| 2026-08-09 00:00 |
08:48:40.31 |
+23:49:39.5 |
HIP 43242 |
18.10 |
| 2026-08-09 12:00 |
08:49:09.34 |
+23:47:52.1 |
HIP 43242 |
21.33 |
| 2026-08-10 00:00 |
08:49:38.37 |
+23:46:04.7 |
HIP 43242 |
26.01 |
| 2026-08-10 12:00 |
08:50:07.37 |
+23:44:17.2 |
HIP 43242 |
31.50 |
| 2026-08-11 00:00 |
08:50:36.36 |
+23:42:29.7 |
HIP 43242 |
37.45 |
| 2026-08-11 12:00 |
08:51:05.34 |
+23:40:42.1 |
HIP 43614 |
34.78 |
| 2026-08-12 00:00 |
08:51:34.29 |
+23:38:54.4 |
HIP 43614 |
28.77 |
| 2026-08-12 12:00 |
08:52:03.23 |
+23:37:06.7 |
HIP 43614 |
23.25 |
| 2026-08-13 00:00 |
08:52:32.15 |
+23:35:19.0 |
HIP 43614 |
18.64 |
| 2026-08-13 12:00 |
08:53:01.05 |
+23:33:31.2 |
HIP 43614 |
15.79 |
| 2026-08-14 00:00 |
08:53:29.92 |
+23:31:43.4 |
HIP 43614 |
15.65 |
| 2026-08-14 12:00 |
08:53:58.78 |
+23:29:55.6 |
HIP 43614 |
18.30 |
| 2026-08-15 00:00 |
08:54:27.61 |
+23:28:07.7 |
HIP 43614 |
22.78 |
| 2026-08-15 12:00 |
08:54:56.42 |
+23:26:19.9 |
HIP 43856 |
26.97 |
| 2026-08-16 00:00 |
08:55:25.20 |
+23:24:32.0 |
HIP 43856 |
22.13 |
| 2026-08-16 12:00 |
08:55:53.97 |
+23:22:44.1 |
HIP 43856 |
18.59 |
| 2026-08-17 00:00 |
08:56:22.70 |
+23:20:56.2 |
HIP 43856 |
17.19 |
| 2026-08-17 12:00 |
08:56:51.41 |
+23:19:08.3 |
HIP 43856 |
18.41 |
| 2026-08-18 00:00 |
08:57:20.10 |
+23:17:20.4 |
HIP 43856 |
21.82 |
| 2026-08-18 12:00 |
08:57:48.76 |
+23:15:32.5 |
HIP 43856 |
26.57 |
| 2026-08-19 00:00 |
08:58:17.39 |
+23:13:44.6 |
HIP 44120 |
28.37 |