C/2025 D6 (ATLAS)
| Parameter |
Value |
| Designation |
C/2025 D6 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-12-11T08:17:56.722560Z |
| Orbit solution date (soln_date, UTC) |
2025-10-28T16:12:42Z |
| Obs used |
144 |
| NEO |
- |
| M1 |
12.600 |
| K1 |
10.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2025-02-26T06:35:48.595200Z |
| Discovery magnitude (MPC) |
18.48 o |
| Discovery observatory (MPC) |
W68 · ATLAS Chile, Rio Hurtado |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2025-03-22.0000000 |
| e |
0.99797059 |
| q (au) |
2.503681 |
| a (au) |
1233.700697 |
| i (deg) |
145.789062 |
| Ω (om, deg) |
151.490101 |
| ω (w, deg) |
285.394018 |
| M (ma, deg) |
0.002289 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.398 + 4.428\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.398 |
| n |
4.428 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.943 |
| δ90 |
1.000 |
| 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) |
| 2026-02-03 00:00 |
09:48:39.89 |
+23:35:45.0 |
HIP 48023 |
18.06 |
| 2026-02-03 12:00 |
09:47:59.48 |
+23:41:10.9 |
HIP 48023 |
8.84 |
| 2026-02-04 00:00 |
09:47:19.01 |
+23:46:35.3 |
HIP 48023 |
7.76 |
| 2026-02-04 12:00 |
09:46:38.50 |
+23:51:58.0 |
HIP 47908 |
12.16 |
| 2026-02-05 00:00 |
09:45:57.96 |
+23:57:19.1 |
HIP 47908 |
10.97 |
| 2026-02-05 12:00 |
09:45:17.38 |
+24:02:38.5 |
HIP 47908 |
17.93 |
| 2026-02-06 00:00 |
09:44:36.77 |
+24:07:56.1 |
HIP 47908 |
27.38 |
| 2026-02-06 12:00 |
09:43:56.13 |
+24:13:12.1 |
HIP 47685 |
24.31 |
| 2026-02-07 00:00 |
09:43:15.49 |
+24:18:26.2 |
HIP 47685 |
17.94 |
| 2026-02-07 12:00 |
09:42:34.83 |
+24:23:38.5 |
HIP 47685 |
16.71 |
| 2026-02-08 00:00 |
09:41:54.16 |
+24:28:49.0 |
HIP 47685 |
21.50 |
| 2026-02-08 12:00 |
09:41:13.49 |
+24:33:57.6 |
HIP 47685 |
29.49 |
| 2026-02-09 00:00 |
09:40:32.83 |
+24:39:04.2 |
HIP 47354 |
28.55 |
| 2026-02-09 12:00 |
09:39:52.17 |
+24:44:08.9 |
HIP 47354 |
26.46 |
| 2026-02-10 00:00 |
09:39:11.54 |
+24:49:11.7 |
HIP 47247 |
20.58 |
| 2026-02-10 12:00 |
09:38:30.92 |
+24:54:12.4 |
HIP 47247 |
16.80 |
| 2026-02-11 00:00 |
09:37:50.33 |
+24:59:11.1 |
HIP 47247 |
18.97 |
| 2026-02-11 12:00 |
09:37:09.77 |
+25:04:07.7 |
HIP 47298 |
24.11 |
| 2026-02-12 00:00 |
09:36:29.25 |
+25:09:02.2 |
HIP 47026 |
24.68 |
| 2026-02-12 12:00 |
09:35:48.78 |
+25:13:54.6 |
HIP 47026 |
22.33 |
| 2026-02-13 00:00 |
09:35:08.35 |
+25:18:44.9 |
HIP 47026 |
24.53 |
| 2026-02-13 12:00 |
09:34:27.97 |
+25:23:32.9 |
HIP 47026 |
30.29 |
| 2026-02-14 00:00 |
09:33:47.66 |
+25:28:18.8 |
HIP 46935 |
35.99 |
| 2026-02-14 12:00 |
09:33:07.41 |
+25:33:02.5 |
HIP 46702 |
36.92 |
| 2026-02-15 00:00 |
09:32:27.23 |
+25:37:43.9 |
HIP 46702 |
27.47 |
| 2026-02-15 12:00 |
09:31:47.13 |
+25:42:23.1 |
HIP 46702 |
18.86 |
| 2026-02-16 00:00 |
09:31:07.11 |
+25:47:00.0 |
HIP 46702 |
12.80 |
| 2026-02-16 12:00 |
09:30:27.18 |
+25:51:34.6 |
HIP 46702 |
13.30 |
| 2026-02-17 00:00 |
09:29:47.34 |
+25:56:06.8 |
HIP 46702 |
19.80 |
| 2026-02-17 12:00 |
09:29:07.60 |
+26:00:36.8 |
HIP 46490 |
12.51 |
| 2026-02-18 00:00 |
09:28:27.96 |
+26:05:04.3 |
HIP 46490 |
9.87 |
| 2026-02-18 12:00 |
09:27:48.43 |
+26:09:29.5 |
HIP 46490 |
15.35 |
| 2026-02-19 00:00 |
09:27:09.01 |
+26:13:52.3 |
HIP 46325 |
9.23 |
| 2026-02-19 12:00 |
09:26:29.71 |
+26:18:12.7 |
HIP 46325 |
4.15 |
| 2026-02-20 00:00 |
09:25:50.53 |
+26:22:30.7 |
HIP 46255 |
10.25 |
| 2026-02-20 12:00 |
09:25:11.49 |
+26:26:46.2 |
HIP 46153 |
15.49 |
| 2026-02-21 00:00 |
09:24:32.58 |
+26:30:59.3 |
HIP 46153 |
10.33 |
| 2026-02-21 12:00 |
09:23:53.80 |
+26:35:09.9 |
HIP 46153 |
12.65 |
| 2026-02-22 00:00 |
09:23:15.17 |
+26:39:18.1 |
HIP 46153 |
19.92 |
| 2026-02-22 12:00 |
09:22:36.69 |
+26:43:23.8 |
HIP 45914 |
14.04 |
| 2026-02-23 00:00 |
09:21:58.36 |
+26:47:27.1 |
HIP 45914 |
4.76 |
| 2026-02-23 12:00 |
09:21:20.19 |
+26:51:27.8 |
HIP 45914 |
5.18 |
| 2026-02-24 00:00 |
09:20:42.18 |
+26:55:26.1 |
HIP 45914 |
14.38 |