| 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 |
-0.999 |
| 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) |
| 2026-03-26 00:00 |
18:13:25.20 |
-27:01:47.8 |
HIP 89302 |
11.19 |
| 2026-03-26 12:00 |
18:13:30.28 |
-27:00:34.4 |
HIP 89302 |
12.58 |
| 2026-03-27 00:00 |
18:13:34.90 |
-26:59:20.8 |
HIP 89302 |
14.01 |
| 2026-03-27 12:00 |
18:13:39.08 |
-26:58:07.2 |
HIP 89302 |
15.44 |
| 2026-03-28 00:00 |
18:13:42.80 |
-26:56:53.6 |
HIP 89302 |
16.86 |
| 2026-03-28 12:00 |
18:13:46.07 |
-26:55:39.8 |
HIP 89302 |
18.26 |
| 2026-03-29 00:00 |
18:13:48.89 |
-26:54:25.9 |
HIP 89302 |
19.63 |
| 2026-03-29 12:00 |
18:13:51.25 |
-26:53:11.9 |
HIP 89302 |
20.97 |
| 2026-03-30 00:00 |
18:13:53.15 |
-26:51:57.8 |
HIP 89302 |
22.27 |
| 2026-03-30 12:00 |
18:13:54.59 |
-26:50:43.6 |
HIP 89302 |
23.55 |
| 2026-03-31 00:00 |
18:13:55.58 |
-26:49:29.3 |
HIP 89302 |
24.79 |
| 2026-03-31 12:00 |
18:13:56.11 |
-26:48:14.9 |
HIP 89302 |
26.00 |
| 2026-04-01 00:00 |
18:13:56.17 |
-26:47:00.4 |
HIP 89180 |
26.75 |
| 2026-04-01 12:00 |
18:13:55.78 |
-26:45:45.8 |
HIP 89180 |
26.34 |
| 2026-04-02 00:00 |
18:13:54.91 |
-26:44:31.0 |
HIP 89180 |
25.89 |
| 2026-04-02 12:00 |
18:13:53.59 |
-26:43:16.1 |
HIP 89180 |
25.38 |
| 2026-04-03 00:00 |
18:13:51.80 |
-26:42:01.1 |
HIP 89180 |
24.83 |
| 2026-04-03 12:00 |
18:13:49.54 |
-26:40:45.9 |
HIP 89180 |
24.23 |
| 2026-04-04 00:00 |
18:13:46.81 |
-26:39:30.6 |
HIP 89180 |
23.59 |
| 2026-04-04 12:00 |
18:13:43.61 |
-26:38:15.2 |
HIP 89180 |
22.91 |
| 2026-04-05 00:00 |
18:13:39.94 |
-26:36:59.6 |
HIP 89180 |
22.20 |
| 2026-04-05 12:00 |
18:13:35.80 |
-26:35:43.9 |
HIP 89180 |
21.47 |
| 2026-04-06 00:00 |
18:13:31.19 |
-26:34:28.0 |
HIP 89180 |
20.73 |
| 2026-04-06 12:00 |
18:13:26.10 |
-26:33:11.9 |
HIP 89180 |
19.99 |
| 2026-04-07 00:00 |
18:13:20.53 |
-26:31:55.7 |
HIP 89180 |
19.28 |
| 2026-04-07 12:00 |
18:13:14.49 |
-26:30:39.3 |
HIP 89180 |
18.62 |
| 2026-04-08 00:00 |
18:13:07.98 |
-26:29:22.7 |
HIP 89180 |
18.03 |
| 2026-04-08 12:00 |
18:13:00.98 |
-26:28:05.9 |
HIP 89180 |
17.56 |
| 2026-04-09 00:00 |
18:12:53.51 |
-26:26:48.9 |
HIP 89180 |
17.25 |
| 2026-04-09 12:00 |
18:12:45.55 |
-26:25:31.7 |
HIP 89180 |
17.13 |
| 2026-04-10 00:00 |
18:12:37.12 |
-26:24:14.3 |
HIP 89180 |
17.24 |
| 2026-04-10 12:00 |
18:12:28.20 |
-26:22:56.7 |
HIP 89180 |
17.62 |
| 2026-04-11 00:00 |
18:12:18.80 |
-26:21:38.8 |
HIP 89180 |
18.28 |
| 2026-04-11 12:00 |
18:12:08.92 |
-26:20:20.7 |
HIP 89180 |
19.23 |
| 2026-04-12 00:00 |
18:11:58.56 |
-26:19:02.4 |
HIP 89165 |
17.99 |
| 2026-04-12 12:00 |
18:11:47.71 |
-26:17:43.8 |
HIP 89165 |
16.52 |
| 2026-04-13 00:00 |
18:11:36.38 |
-26:16:25.0 |
HIP 89165 |
15.42 |
| 2026-04-13 12:00 |
18:11:24.57 |
-26:15:05.9 |
HIP 89165 |
14.83 |
| 2026-04-14 00:00 |
18:11:12.27 |
-26:13:46.5 |
HIP 89049 |
14.65 |
| 2026-04-14 12:00 |
18:10:59.48 |
-26:12:26.8 |
HIP 89032 |
11.67 |
| 2026-04-15 00:00 |
18:10:46.21 |
-26:11:06.8 |
HIP 89032 |
8.44 |
| 2026-04-15 12:00 |
18:10:32.46 |
-26:09:46.6 |
HIP 89032 |
5.16 |
| 2026-04-16 00:00 |
18:10:18.22 |
-26:08:26.0 |
HIP 89032 |
2.12 |