| Parameter |
Value |
| Designation |
478P/ATLAS |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2024-05-01T18:15:32.791680Z |
| Orbit solution date (soln_date, UTC) |
2024-10-10T17:58:36Z |
| Obs used |
494 |
| NEO |
- |
| M1 |
10.000 |
| K1 |
19.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2017-01-28T11:47:24Z |
| Discovery magnitude (MPC) |
20.80 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-08-06.0000000 |
| e |
0.34362489 |
| q (au) |
2.394062 |
| a (au) |
3.647398 |
| i (deg) |
12.523311 |
| Ω (om, deg) |
127.279868 |
| ω (w, deg) |
13.107152 |
| M (ma, deg) |
321.831235 |
Magnitude
Scatter + Global Linear
$$
M_a = (14.333 + 5.191\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
14.333 |
| n |
5.191 |
| gf |
0.966 |
| gb |
-0.669 |
| k |
0.801 |
| δ90 |
1.339 |
| 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) |
| 2026-09-20 00:00 |
18:31:07.40 |
-19:11:06.9 |
HIP 90801 |
4.28 |
| 2026-09-20 12:00 |
18:31:14.47 |
-19:12:01.8 |
HIP 90801 |
3.41 |
| 2026-09-21 00:00 |
18:31:21.76 |
-19:12:56.3 |
HIP 90801 |
3.47 |
| 2026-09-21 12:00 |
18:31:29.27 |
-19:13:50.4 |
HIP 90801 |
4.49 |
| 2026-09-22 00:00 |
18:31:36.99 |
-19:14:44.1 |
HIP 90801 |
6.03 |
| 2026-09-22 12:00 |
18:31:44.92 |
-19:15:37.5 |
HIP 90801 |
7.82 |
| 2026-09-23 00:00 |
18:31:53.06 |
-19:16:30.4 |
HIP 90836 |
9.00 |
| 2026-09-23 12:00 |
18:32:01.41 |
-19:17:23.0 |
HIP 90836 |
10.06 |
| 2026-09-24 00:00 |
18:32:09.97 |
-19:18:15.1 |
HIP 90870 |
10.84 |
| 2026-09-24 12:00 |
18:32:18.74 |
-19:19:06.9 |
HIP 90870 |
11.75 |
| 2026-09-25 00:00 |
18:32:27.72 |
-19:19:58.3 |
HIP 90870 |
13.00 |
| 2026-09-25 12:00 |
18:32:36.90 |
-19:20:49.3 |
HIP 90870 |
14.51 |
| 2026-09-26 00:00 |
18:32:46.29 |
-19:21:39.8 |
HIP 90870 |
16.24 |
| 2026-09-26 12:00 |
18:32:55.89 |
-19:22:30.0 |
HIP 90870 |
18.13 |
| 2026-09-27 00:00 |
18:33:05.68 |
-19:23:19.8 |
HIP 90870 |
20.16 |
| 2026-09-27 12:00 |
18:33:15.68 |
-19:24:09.2 |
HIP 90870 |
22.30 |
| 2026-09-28 00:00 |
18:33:25.88 |
-19:24:58.1 |
HIP 90870 |
24.54 |
| 2026-09-28 12:00 |
18:33:36.28 |
-19:25:46.7 |
HIP 91051 |
24.23 |
| 2026-09-29 00:00 |
18:33:46.88 |
-19:26:34.8 |
HIP 91051 |
22.41 |
| 2026-09-29 12:00 |
18:33:57.68 |
-19:27:22.5 |
HIP 91051 |
20.75 |
| 2026-09-30 00:00 |
18:34:08.68 |
-19:28:09.8 |
HIP 91051 |
19.32 |
| 2026-09-30 12:00 |
18:34:19.87 |
-19:28:56.7 |
HIP 91051 |
18.18 |
| 2026-10-01 00:00 |
18:34:31.26 |
-19:29:43.2 |
HIP 91051 |
17.41 |
| 2026-10-01 12:00 |
18:34:42.84 |
-19:30:29.3 |
HIP 91051 |
17.10 |
| 2026-10-02 00:00 |
18:34:54.62 |
-19:31:14.9 |
HIP 91135 |
16.62 |
| 2026-10-02 12:00 |
18:35:06.59 |
-19:32:00.1 |
HIP 91135 |
16.40 |
| 2026-10-03 00:00 |
18:35:18.75 |
-19:32:44.9 |
HIP 91135 |
16.68 |
| 2026-10-03 12:00 |
18:35:31.11 |
-19:33:29.3 |
HIP 91135 |
17.47 |
| 2026-10-04 00:00 |
18:35:43.65 |
-19:34:13.2 |
HIP 91135 |
18.71 |
| 2026-10-04 12:00 |
18:35:56.39 |
-19:34:56.7 |
HIP 91135 |
20.35 |
| 2026-10-05 00:00 |
18:36:09.31 |
-19:35:39.7 |
HIP 91135 |
22.32 |
| 2026-10-05 12:00 |
18:36:22.42 |
-19:36:22.3 |
HIP 91344 |
21.13 |
| 2026-10-06 00:00 |
18:36:35.72 |
-19:37:04.5 |
HIP 91344 |
18.03 |
| 2026-10-06 12:00 |
18:36:49.21 |
-19:37:46.2 |
HIP 91344 |
14.92 |
| 2026-10-07 00:00 |
18:37:02.88 |
-19:38:27.5 |
HIP 91344 |
11.84 |
| 2026-10-07 12:00 |
18:37:16.73 |
-19:39:08.3 |
HIP 91344 |
8.88 |
| 2026-10-08 00:00 |
18:37:30.77 |
-19:39:48.7 |
HIP 91344 |
6.25 |
| 2026-10-08 12:00 |
18:37:44.99 |
-19:40:28.6 |
HIP 91344 |
4.69 |
| 2026-10-09 00:00 |
18:37:59.39 |
-19:41:08.1 |
HIP 91344 |
5.31 |
| 2026-10-09 12:00 |
18:38:13.97 |
-19:41:47.1 |
HIP 91344 |
7.66 |
| 2026-10-10 00:00 |
18:38:28.73 |
-19:42:25.6 |
HIP 91344 |
10.68 |
| 2026-10-10 12:00 |
18:38:43.67 |
-19:43:03.7 |
HIP 91344 |
13.98 |
| 2026-10-11 00:00 |
18:38:58.78 |
-19:43:41.3 |
HIP 91344 |
17.42 |