| Parameter |
Value |
| Designation |
414P/STEREO |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-01-25T07:45:13.775040Z |
| Orbit solution date (soln_date, UTC) |
2026-01-07T20:33:37Z |
| Obs used |
300 |
| NEO |
Yes |
| M1 |
20.500 |
| K1 |
39.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-04T02:11:29.184000Z |
| Discovery magnitude (MPC) |
19.10 R |
| Discovery observatory (MPC) |
I41 · Palomar Mountain–ZTF |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-11-22.0000000 |
| e |
0.81171958 |
| q (au) |
0.525961 |
| a (au) |
2.793500 |
| i (deg) |
23.392649 |
| Ω (om, deg) |
257.794317 |
| ω (w, deg) |
210.708294 |
| M (ma, deg) |
140.522045 |
Magnitude
Scatter + Global Linear
$$
M_a = (19.811 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
19.811 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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 |
| 2025-07-28 |
2025-09-23 |
+7.7015 |
+0.046 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
16:26:36.33 |
-19:23:23.1 |
HIP 80544 |
15.49 |
| 2026-07-29 12:00 |
16:26:28.90 |
-19:22:18.4 |
HIP 80544 |
14.64 |
| 2026-07-30 00:00 |
16:26:21.82 |
-19:21:15.0 |
HIP 80544 |
14.04 |
| 2026-07-30 12:00 |
16:26:15.08 |
-19:20:12.7 |
HIP 80544 |
13.68 |
| 2026-07-31 00:00 |
16:26:08.68 |
-19:19:11.5 |
HIP 80544 |
13.55 |
| 2026-07-31 12:00 |
16:26:02.63 |
-19:18:11.6 |
HIP 80544 |
13.62 |
| 2026-08-01 00:00 |
16:25:56.91 |
-19:17:12.8 |
HIP 80544 |
13.87 |
| 2026-08-01 12:00 |
16:25:51.52 |
-19:16:15.2 |
HIP 80544 |
14.26 |
| 2026-08-02 00:00 |
16:25:46.47 |
-19:15:18.7 |
HIP 80544 |
14.75 |
| 2026-08-02 12:00 |
16:25:41.75 |
-19:14:23.4 |
HIP 80544 |
15.32 |
| 2026-08-03 00:00 |
16:25:37.36 |
-19:13:29.2 |
HIP 80544 |
15.93 |
| 2026-08-03 12:00 |
16:25:33.30 |
-19:12:36.2 |
HIP 80544 |
16.56 |
| 2026-08-04 00:00 |
16:25:29.57 |
-19:11:44.3 |
HIP 80544 |
17.20 |
| 2026-08-04 12:00 |
16:25:26.16 |
-19:10:53.5 |
HIP 80544 |
17.82 |
| 2026-08-05 00:00 |
16:25:23.07 |
-19:10:03.8 |
HIP 80544 |
18.43 |
| 2026-08-05 12:00 |
16:25:20.31 |
-19:09:15.2 |
HIP 80544 |
19.01 |
| 2026-08-06 00:00 |
16:25:17.86 |
-19:08:27.8 |
HIP 80544 |
19.54 |
| 2026-08-06 12:00 |
16:25:15.73 |
-19:07:41.4 |
HIP 80544 |
20.04 |
| 2026-08-07 00:00 |
16:25:13.92 |
-19:06:56.2 |
HIP 80544 |
20.49 |
| 2026-08-07 12:00 |
16:25:12.42 |
-19:06:12.0 |
HIP 80544 |
20.90 |
| 2026-08-08 00:00 |
16:25:11.23 |
-19:05:28.8 |
HIP 80544 |
21.25 |
| 2026-08-08 12:00 |
16:25:10.35 |
-19:04:46.8 |
HIP 80544 |
21.55 |
| 2026-08-09 00:00 |
16:25:09.78 |
-19:04:05.8 |
HIP 80544 |
21.79 |
| 2026-08-09 12:00 |
16:25:09.52 |
-19:03:25.9 |
HIP 80544 |
21.98 |
| 2026-08-10 00:00 |
16:25:09.56 |
-19:02:47.0 |
HIP 80544 |
22.11 |
| 2026-08-10 12:00 |
16:25:09.91 |
-19:02:09.1 |
HIP 80544 |
22.19 |
| 2026-08-11 00:00 |
16:25:10.56 |
-19:01:32.3 |
HIP 80544 |
22.21 |
| 2026-08-11 12:00 |
16:25:11.50 |
-19:00:56.4 |
HIP 80544 |
22.18 |
| 2026-08-12 00:00 |
16:25:12.75 |
-19:00:21.6 |
HIP 80544 |
22.09 |
| 2026-08-12 12:00 |
16:25:14.29 |
-18:59:47.8 |
HIP 80544 |
21.95 |
| 2026-08-13 00:00 |
16:25:16.12 |
-18:59:15.0 |
HIP 80544 |
21.76 |
| 2026-08-13 12:00 |
16:25:18.25 |
-18:58:43.1 |
HIP 80544 |
21.53 |
| 2026-08-14 00:00 |
16:25:20.67 |
-18:58:12.2 |
HIP 80544 |
21.24 |
| 2026-08-14 12:00 |
16:25:23.37 |
-18:57:42.3 |
HIP 80544 |
20.92 |
| 2026-08-15 00:00 |
16:25:26.36 |
-18:57:13.3 |
HIP 80544 |
20.55 |
| 2026-08-15 12:00 |
16:25:29.63 |
-18:56:45.3 |
HIP 80544 |
20.15 |
| 2026-08-16 00:00 |
16:25:33.19 |
-18:56:18.2 |
HIP 80544 |
19.72 |
| 2026-08-16 12:00 |
16:25:37.02 |
-18:55:52.0 |
HIP 80544 |
19.27 |
| 2026-08-17 00:00 |
16:25:41.13 |
-18:55:26.7 |
HIP 80544 |
18.80 |
| 2026-08-17 12:00 |
16:25:45.52 |
-18:55:02.3 |
HIP 80544 |
18.32 |
| 2026-08-18 00:00 |
16:25:50.18 |
-18:54:38.8 |
HIP 80544 |
17.84 |
| 2026-08-18 12:00 |
16:25:55.11 |
-18:54:16.2 |
HIP 80544 |
17.38 |
| 2026-08-19 00:00 |
16:26:00.30 |
-18:53:54.4 |
HIP 80544 |
16.95 |