| Parameter |
Value |
| Designation |
475P/Spacewatch-LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2004-09-20T05:48:26.389440Z |
| Orbit solution date (soln_date, UTC) |
2025-06-26T10:13:27Z |
| Obs used |
159 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
15.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2023-11-11T05:51:29.030400Z |
| Discovery magnitude (MPC) |
20.80 G |
| Discovery observatory (MPC) |
J04 · ESA Optical Ground Station, Tenerife |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2012-08-10.0000000 |
| e |
0.43983107 |
| q (au) |
4.088003 |
| a (au) |
7.297804 |
| i (deg) |
14.525819 |
| Ω (om, deg) |
147.492673 |
| ω (w, deg) |
40.536988 |
| M (ma, deg) |
144.019928 |
Magnitude
Scatter + Global Linear
$$
M_a = (6.697 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
6.697 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
18:00:51.25 |
-10:03:17.7 |
HIP 88335 |
23.13 |
| 2026-07-29 12:00 |
18:00:42.40 |
-10:04:28.3 |
HIP 88335 |
25.15 |
| 2026-07-30 00:00 |
18:00:33.69 |
-10:05:39.2 |
HIP 88335 |
27.22 |
| 2026-07-30 12:00 |
18:00:25.12 |
-10:06:50.4 |
HIP 88048 |
29.00 |
| 2026-07-31 00:00 |
18:00:16.68 |
-10:08:02.0 |
HIP 88048 |
28.46 |
| 2026-07-31 12:00 |
18:00:08.39 |
-10:09:14.0 |
HIP 88048 |
28.14 |
| 2026-08-01 00:00 |
18:00:00.24 |
-10:10:26.3 |
HIP 88048 |
28.04 |
| 2026-08-01 12:00 |
17:59:52.24 |
-10:11:38.9 |
HIP 88048 |
28.16 |
| 2026-08-02 00:00 |
17:59:44.38 |
-10:12:51.9 |
HIP 88048 |
28.48 |
| 2026-08-02 12:00 |
17:59:36.66 |
-10:14:05.2 |
HIP 88048 |
29.00 |
| 2026-08-03 00:00 |
17:59:29.09 |
-10:15:18.8 |
HIP 88048 |
29.69 |
| 2026-08-03 12:00 |
17:59:21.67 |
-10:16:32.7 |
HIP 88048 |
30.55 |
| 2026-08-04 00:00 |
17:59:14.39 |
-10:17:46.9 |
HIP 88048 |
31.54 |
| 2026-08-04 12:00 |
17:59:07.27 |
-10:19:01.4 |
HIP 88048 |
32.65 |
| 2026-08-05 00:00 |
17:59:00.29 |
-10:20:16.2 |
HIP 88048 |
33.87 |
| 2026-08-05 12:00 |
17:58:53.47 |
-10:21:31.3 |
HIP 88048 |
35.18 |
| 2026-08-06 00:00 |
17:58:46.80 |
-10:22:46.7 |
HIP 87829 |
36.25 |
| 2026-08-06 12:00 |
17:58:40.28 |
-10:24:02.3 |
HIP 87829 |
35.16 |
| 2026-08-07 00:00 |
17:58:33.91 |
-10:25:18.3 |
HIP 87829 |
34.20 |
| 2026-08-07 12:00 |
17:58:27.70 |
-10:26:34.4 |
HIP 87829 |
33.37 |
| 2026-08-08 00:00 |
17:58:21.64 |
-10:27:50.9 |
HIP 87829 |
32.68 |
| 2026-08-08 12:00 |
17:58:15.74 |
-10:29:07.6 |
HIP 87829 |
32.13 |
| 2026-08-09 00:00 |
17:58:10.00 |
-10:30:24.5 |
HIP 87829 |
31.71 |
| 2026-08-09 12:00 |
17:58:04.42 |
-10:31:41.7 |
HIP 87829 |
31.44 |
| 2026-08-10 00:00 |
17:57:58.99 |
-10:32:59.1 |
HIP 87829 |
31.32 |
| 2026-08-10 12:00 |
17:57:53.73 |
-10:34:16.7 |
HIP 87829 |
31.33 |
| 2026-08-11 00:00 |
17:57:48.62 |
-10:35:34.5 |
HIP 87829 |
31.47 |
| 2026-08-11 12:00 |
17:57:43.68 |
-10:36:52.6 |
HIP 87829 |
31.75 |
| 2026-08-12 00:00 |
17:57:38.89 |
-10:38:10.8 |
HIP 87829 |
32.14 |
| 2026-08-12 12:00 |
17:57:34.27 |
-10:39:29.3 |
HIP 87829 |
32.65 |
| 2026-08-13 00:00 |
17:57:29.82 |
-10:40:47.9 |
HIP 87829 |
33.27 |
| 2026-08-13 12:00 |
17:57:25.53 |
-10:42:06.7 |
HIP 87829 |
33.98 |
| 2026-08-14 00:00 |
17:57:21.40 |
-10:43:25.7 |
HIP 87829 |
34.77 |
| 2026-08-14 12:00 |
17:57:17.43 |
-10:44:44.9 |
HIP 87829 |
35.64 |
| 2026-08-15 00:00 |
17:57:13.64 |
-10:46:04.2 |
HIP 87829 |
36.58 |
| 2026-08-15 12:00 |
17:57:10.00 |
-10:47:23.7 |
HIP 87829 |
37.58 |
| 2026-08-16 00:00 |
17:57:06.54 |
-10:48:43.3 |
HIP 87829 |
38.63 |
| 2026-08-16 12:00 |
17:57:03.24 |
-10:50:03.1 |
HIP 87829 |
39.73 |
| 2026-08-17 00:00 |
17:57:00.11 |
-10:51:23.0 |
HIP 87829 |
40.87 |
| 2026-08-17 12:00 |
17:56:57.14 |
-10:52:43.0 |
HIP 87921 |
40.42 |
| 2026-08-18 00:00 |
17:56:54.34 |
-10:54:03.1 |
HIP 87921 |
39.30 |
| 2026-08-18 12:00 |
17:56:51.71 |
-10:55:23.4 |
HIP 87921 |
38.18 |
| 2026-08-19 00:00 |
17:56:49.25 |
-10:56:43.7 |
HIP 87921 |
37.08 |