| Parameter |
Value |
| Designation |
C/2023 K1 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-09-07T17:57:17.956800Z |
| Orbit solution date (soln_date, UTC) |
2024-04-13T16:42:46Z |
| Obs used |
218 |
| NEO |
- |
| M1 |
6.200 |
| K1 |
27.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2023-05-27T02:15:06.998400Z |
| Discovery magnitude (MPC) |
18.64 c |
| Discovery observatory (MPC) |
M22 · ATLAS South Africa, Sutherland |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-07-23.0000000 |
| e |
0.99718017 |
| q (au) |
2.039540 |
| a (au) |
723.284257 |
| i (deg) |
137.998404 |
| Ω (om, deg) |
223.706343 |
| ω (w, deg) |
337.472407 |
| M (ma, deg) |
359.997631 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.725 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.725 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.553 |
| k |
1.000 |
| 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 |
| 2023-05-27 |
2023-09-02 |
+17.2597 |
-6.056 |
| 2023-09-09 |
2024-03-19 |
+19.3353 |
-8.589 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
08:21:18.24 |
+58:54:28.8 |
HIP 40976 |
11.62 |
| 2026-06-01 12:00 |
08:21:27.36 |
+58:52:44.2 |
HIP 40976 |
13.08 |
| 2026-06-02 00:00 |
08:21:36.60 |
+58:51:00.1 |
HIP 40976 |
14.69 |
| 2026-06-02 12:00 |
08:21:45.95 |
+58:49:16.5 |
HIP 40976 |
16.40 |
| 2026-06-03 00:00 |
08:21:55.42 |
+58:47:33.5 |
HIP 40976 |
18.19 |
| 2026-06-03 12:00 |
08:22:05.00 |
+58:45:50.9 |
HIP 40976 |
20.04 |
| 2026-06-04 00:00 |
08:22:14.70 |
+58:44:08.8 |
HIP 40976 |
21.92 |
| 2026-06-04 12:00 |
08:22:24.50 |
+58:42:27.3 |
HIP 40976 |
23.84 |
| 2026-06-05 00:00 |
08:22:34.42 |
+58:40:46.2 |
HIP 40976 |
25.79 |
| 2026-06-05 12:00 |
08:22:44.45 |
+58:39:05.7 |
HIP 40976 |
27.76 |
| 2026-06-06 00:00 |
08:22:54.58 |
+58:37:25.7 |
HIP 40976 |
29.74 |
| 2026-06-06 12:00 |
08:23:04.82 |
+58:35:46.2 |
HIP 40976 |
31.74 |
| 2026-06-07 00:00 |
08:23:15.17 |
+58:34:07.2 |
HIP 40976 |
33.75 |
| 2026-06-07 12:00 |
08:23:25.62 |
+58:32:28.8 |
HIP 41481 |
34.06 |
| 2026-06-08 00:00 |
08:23:36.17 |
+58:30:50.9 |
HIP 41481 |
33.30 |
| 2026-06-08 12:00 |
08:23:46.82 |
+58:29:13.5 |
HIP 41481 |
32.63 |
| 2026-06-09 00:00 |
08:23:57.58 |
+58:27:36.7 |
HIP 41481 |
32.07 |
| 2026-06-09 12:00 |
08:24:08.43 |
+58:26:00.4 |
HIP 41468 |
30.45 |
| 2026-06-10 00:00 |
08:24:19.39 |
+58:24:24.7 |
HIP 41468 |
28.44 |
| 2026-06-10 12:00 |
08:24:30.44 |
+58:22:49.5 |
HIP 41468 |
26.43 |
| 2026-06-11 00:00 |
08:24:41.58 |
+58:21:14.8 |
HIP 41468 |
24.45 |
| 2026-06-11 12:00 |
08:24:52.82 |
+58:19:40.7 |
HIP 41468 |
22.48 |
| 2026-06-12 00:00 |
08:25:04.15 |
+58:18:07.2 |
HIP 41468 |
20.54 |
| 2026-06-12 12:00 |
08:25:15.58 |
+58:16:34.2 |
HIP 41468 |
18.64 |
| 2026-06-13 00:00 |
08:25:27.10 |
+58:15:01.7 |
HIP 41468 |
16.78 |
| 2026-06-13 12:00 |
08:25:38.70 |
+58:13:29.9 |
HIP 41468 |
15.00 |
| 2026-06-14 00:00 |
08:25:50.40 |
+58:11:58.6 |
HIP 41468 |
13.32 |
| 2026-06-14 12:00 |
08:26:02.18 |
+58:10:27.9 |
HIP 41468 |
11.78 |
| 2026-06-15 00:00 |
08:26:14.04 |
+58:08:57.7 |
HIP 41468 |
10.45 |
| 2026-06-15 12:00 |
08:26:26.00 |
+58:07:28.2 |
HIP 41468 |
9.42 |
| 2026-06-16 00:00 |
08:26:38.03 |
+58:05:59.2 |
HIP 41468 |
8.79 |
| 2026-06-16 12:00 |
08:26:50.15 |
+58:04:30.8 |
HIP 41468 |
8.67 |
| 2026-06-17 00:00 |
08:27:02.35 |
+58:03:03.0 |
HIP 41468 |
9.06 |
| 2026-06-17 12:00 |
08:27:14.62 |
+58:01:35.7 |
HIP 41468 |
9.92 |
| 2026-06-18 00:00 |
08:27:26.98 |
+58:00:09.1 |
HIP 41468 |
11.13 |
| 2026-06-18 12:00 |
08:27:39.41 |
+57:58:43.1 |
HIP 41468 |
12.59 |
| 2026-06-19 00:00 |
08:27:51.92 |
+57:57:17.6 |
HIP 41468 |
14.23 |
| 2026-06-19 12:00 |
08:28:04.50 |
+57:55:52.8 |
HIP 41468 |
16.00 |
| 2026-06-20 00:00 |
08:28:17.15 |
+57:54:28.6 |
HIP 41468 |
17.85 |
| 2026-06-20 12:00 |
08:28:29.87 |
+57:53:04.9 |
HIP 41468 |
19.77 |
| 2026-06-21 00:00 |
08:28:42.67 |
+57:51:41.9 |
HIP 41468 |
21.73 |
| 2026-06-21 12:00 |
08:28:55.53 |
+57:50:19.5 |
HIP 41468 |
23.73 |
| 2026-06-22 00:00 |
08:29:08.47 |
+57:48:57.7 |
HIP 41468 |
25.75 |