C/2025 W1 (Sankovich)
| Parameter |
Value |
| Designation |
C/2025 W1 (Sankovich) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2025-02-17T17:39:07.554240Z |
| Orbit solution date (soln_date, UTC) |
2025-12-18T15:12:26Z |
| Obs used |
80 |
| NEO |
- |
| M1 |
9.400 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-11-20T03:53:37.536000Z |
| Discovery magnitude (MPC) |
19.80 R |
| Discovery observatory (MPC) |
X19 · Santel Observatory, El Leoncito |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-11-26.0000000 |
| e |
0.99973624 |
| q (au) |
4.170169 |
| a (au) |
15810.455383 |
| i (deg) |
79.800605 |
| Ω (om, deg) |
95.890663 |
| ω (w, deg) |
250.634842 |
| M (ma, deg) |
0.000139 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.395 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.395 |
| n |
6.000 |
| gf |
0.915 |
| gb |
-0.828 |
| k |
0.806 |
| δ90 |
4.574 |
| 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) |
| 2026-02-03 00:00 |
04:44:58.29 |
-40:41:48.6 |
HIP 21998 |
26.14 |
| 2026-02-03 12:00 |
04:44:50.50 |
-40:33:51.1 |
HIP 21998 |
32.55 |
| 2026-02-04 00:00 |
04:44:43.00 |
-40:25:53.2 |
HIP 22281 |
35.70 |
| 2026-02-04 12:00 |
04:44:35.79 |
-40:17:54.9 |
HIP 22178 |
30.48 |
| 2026-02-05 00:00 |
04:44:28.87 |
-40:09:56.2 |
HIP 22178 |
26.05 |
| 2026-02-05 12:00 |
04:44:22.24 |
-40:01:57.0 |
HIP 22178 |
23.60 |
| 2026-02-06 00:00 |
04:44:15.90 |
-39:53:57.6 |
HIP 22178 |
23.74 |
| 2026-02-06 12:00 |
04:44:09.83 |
-39:45:57.8 |
HIP 22178 |
26.43 |
| 2026-02-07 00:00 |
04:44:04.05 |
-39:37:57.7 |
HIP 22144 |
27.14 |
| 2026-02-07 12:00 |
04:43:58.56 |
-39:29:57.4 |
HIP 22144 |
24.15 |
| 2026-02-08 00:00 |
04:43:53.34 |
-39:21:56.8 |
HIP 22144 |
23.62 |
| 2026-02-08 12:00 |
04:43:48.40 |
-39:13:56.1 |
HIP 22144 |
25.70 |
| 2026-02-09 00:00 |
04:43:43.73 |
-39:05:55.2 |
HIP 21911 |
18.95 |
| 2026-02-09 12:00 |
04:43:39.35 |
-38:57:54.2 |
HIP 21911 |
13.09 |
| 2026-02-10 00:00 |
04:43:35.23 |
-38:49:53.1 |
HIP 22030 |
10.21 |
| 2026-02-10 12:00 |
04:43:31.39 |
-38:41:51.9 |
HIP 22030 |
7.62 |
| 2026-02-11 00:00 |
04:43:27.82 |
-38:33:50.7 |
HIP 22030 |
11.86 |
| 2026-02-11 12:00 |
04:43:24.52 |
-38:25:49.4 |
HIP 22030 |
18.77 |
| 2026-02-12 00:00 |
04:43:21.49 |
-38:17:48.2 |
HIP 22030 |
26.31 |
| 2026-02-12 12:00 |
04:43:18.72 |
-38:09:47.1 |
HIP 21766 |
33.41 |
| 2026-02-13 00:00 |
04:43:16.22 |
-38:01:46.0 |
HIP 21869 |
28.35 |
| 2026-02-13 12:00 |
04:43:13.98 |
-37:53:45.0 |
HIP 21869 |
21.36 |
| 2026-02-14 00:00 |
04:43:12.01 |
-37:45:44.2 |
HIP 21869 |
15.47 |
| 2026-02-14 12:00 |
04:43:10.29 |
-37:37:43.5 |
HIP 21869 |
12.34 |
| 2026-02-15 00:00 |
04:43:08.83 |
-37:29:43.0 |
HIP 21869 |
13.96 |
| 2026-02-15 12:00 |
04:43:07.63 |
-37:21:42.8 |
HIP 21861 |
18.24 |
| 2026-02-16 00:00 |
04:43:06.69 |
-37:13:42.8 |
HIP 21861 |
13.56 |
| 2026-02-16 12:00 |
04:43:06.00 |
-37:05:43.1 |
HIP 21861 |
12.82 |
| 2026-02-17 00:00 |
04:43:05.56 |
-36:57:43.6 |
HIP 21861 |
16.54 |
| 2026-02-17 12:00 |
04:43:05.37 |
-36:49:44.6 |
HIP 21861 |
22.62 |
| 2026-02-18 00:00 |
04:43:05.43 |
-36:41:45.9 |
HIP 22043 |
21.36 |
| 2026-02-18 12:00 |
04:43:05.74 |
-36:33:47.5 |
HIP 22043 |
16.92 |
| 2026-02-19 00:00 |
04:43:06.29 |
-36:25:49.6 |
HIP 22043 |
15.57 |
| 2026-02-19 12:00 |
04:43:07.09 |
-36:17:52.2 |
HIP 22043 |
17.99 |
| 2026-02-20 00:00 |
04:43:08.13 |
-36:09:55.2 |
HIP 22043 |
23.01 |
| 2026-02-20 12:00 |
04:43:09.41 |
-36:01:58.7 |
HIP 22043 |
29.33 |
| 2026-02-21 00:00 |
04:43:10.92 |
-35:54:02.7 |
HIP 21872 |
28.42 |
| 2026-02-21 12:00 |
04:43:12.68 |
-35:46:07.3 |
HIP 21872 |
21.82 |
| 2026-02-22 00:00 |
04:43:14.66 |
-35:38:12.5 |
HIP 21872 |
16.48 |
| 2026-02-22 12:00 |
04:43:16.88 |
-35:30:18.2 |
HIP 21872 |
13.94 |
| 2026-02-23 00:00 |
04:43:19.34 |
-35:22:24.6 |
HIP 21872 |
15.61 |
| 2026-02-23 12:00 |
04:43:22.02 |
-35:14:31.7 |
HIP 21872 |
20.48 |
| 2026-02-24 00:00 |
04:43:24.92 |
-35:06:39.4 |
HIP 21956 |
16.20 |