C/2022 Q2 (ATLAS)
| Parameter |
Value |
| Designation |
C/2022 Q2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2023-01-31T14:05:21.716160Z |
| Orbit solution date (soln_date, UTC) |
2023-08-06T18:13:02Z |
| Obs used |
591 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
9.750 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2022-08-27T14:05:17.059200Z |
| Discovery magnitude (MPC) |
19.06 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-11-02.0000000 |
| e |
0.94987994 |
| q (au) |
1.644140 |
| a (au) |
32.804037 |
| i (deg) |
151.486615 |
| Ω (om, deg) |
352.943256 |
| ω (w, deg) |
44.060185 |
| M (ma, deg) |
359.524797 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.015 + 3.982\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.015 |
| n |
3.982 |
| gf |
1.000 |
| gb |
-0.839 |
| k |
0.998 |
| 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 |
| 2022-08-27 |
2022-12-21 |
+0.4118 |
-0.203 |
| 2023-04-03 |
2023-07-16 |
-8.5392 |
+4.736 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
11:51:15.39 |
+01:18:16.3 |
HIP 57757 |
28.93 |
| 2026-02-03 12:00 |
11:51:04.08 |
+01:19:12.2 |
HIP 57757 |
27.32 |
| 2026-02-04 00:00 |
11:50:52.69 |
+01:20:08.6 |
HIP 57757 |
25.94 |
| 2026-02-04 12:00 |
11:50:41.23 |
+01:21:05.5 |
HIP 57757 |
24.83 |
| 2026-02-05 00:00 |
11:50:29.68 |
+01:22:02.9 |
HIP 57757 |
24.05 |
| 2026-02-05 12:00 |
11:50:18.07 |
+01:23:00.8 |
HIP 57757 |
23.63 |
| 2026-02-06 00:00 |
11:50:06.37 |
+01:23:59.1 |
HIP 57757 |
23.61 |
| 2026-02-06 12:00 |
11:49:54.60 |
+01:24:57.9 |
HIP 57757 |
23.99 |
| 2026-02-07 00:00 |
11:49:42.75 |
+01:25:57.2 |
HIP 57757 |
24.75 |
| 2026-02-07 12:00 |
11:49:30.84 |
+01:26:56.9 |
HIP 57757 |
25.88 |
| 2026-02-08 00:00 |
11:49:18.84 |
+01:27:57.0 |
HIP 57757 |
27.34 |
| 2026-02-08 12:00 |
11:49:06.78 |
+01:28:57.6 |
HIP 57757 |
29.08 |
| 2026-02-09 00:00 |
11:48:54.65 |
+01:29:58.7 |
HIP 57757 |
31.05 |
| 2026-02-09 12:00 |
11:48:42.44 |
+01:31:00.2 |
HIP 57757 |
33.24 |
| 2026-02-10 00:00 |
11:48:30.17 |
+01:32:02.1 |
HIP 57525 |
32.96 |
| 2026-02-10 12:00 |
11:48:17.83 |
+01:33:04.4 |
HIP 57525 |
30.63 |
| 2026-02-11 00:00 |
11:48:05.42 |
+01:34:07.2 |
HIP 57525 |
28.46 |
| 2026-02-11 12:00 |
11:47:52.95 |
+01:35:10.3 |
HIP 57525 |
26.51 |
| 2026-02-12 00:00 |
11:47:40.41 |
+01:36:13.9 |
HIP 57525 |
24.84 |
| 2026-02-12 12:00 |
11:47:27.80 |
+01:37:17.8 |
HIP 57525 |
23.50 |
| 2026-02-13 00:00 |
11:47:15.14 |
+01:38:22.2 |
HIP 57525 |
22.58 |
| 2026-02-13 12:00 |
11:47:02.41 |
+01:39:26.9 |
HIP 57525 |
22.13 |
| 2026-02-14 00:00 |
11:46:49.62 |
+01:40:32.0 |
HIP 57525 |
22.18 |
| 2026-02-14 12:00 |
11:46:36.77 |
+01:41:37.5 |
HIP 57525 |
22.74 |
| 2026-02-15 00:00 |
11:46:23.86 |
+01:42:43.3 |
HIP 57315 |
21.14 |
| 2026-02-15 12:00 |
11:46:10.89 |
+01:43:49.5 |
HIP 57315 |
18.70 |
| 2026-02-16 00:00 |
11:45:57.87 |
+01:44:56.1 |
HIP 57315 |
16.59 |
| 2026-02-16 12:00 |
11:45:44.79 |
+01:46:03.0 |
HIP 57315 |
14.98 |
| 2026-02-17 00:00 |
11:45:31.66 |
+01:47:10.2 |
HIP 57315 |
14.06 |
| 2026-02-17 12:00 |
11:45:18.47 |
+01:48:17.8 |
HIP 57315 |
13.95 |
| 2026-02-18 00:00 |
11:45:05.24 |
+01:49:25.6 |
HIP 57315 |
14.71 |
| 2026-02-18 12:00 |
11:44:51.95 |
+01:50:33.8 |
HIP 57315 |
16.20 |
| 2026-02-19 00:00 |
11:44:38.61 |
+01:51:42.3 |
HIP 57315 |
18.27 |
| 2026-02-19 12:00 |
11:44:25.22 |
+01:52:51.1 |
HIP 57315 |
20.74 |
| 2026-02-20 00:00 |
11:44:11.79 |
+01:54:00.2 |
HIP 57315 |
23.50 |
| 2026-02-20 12:00 |
11:43:58.30 |
+01:55:09.6 |
HIP 57315 |
26.46 |
| 2026-02-21 00:00 |
11:43:44.78 |
+01:56:19.2 |
HIP 57315 |
29.56 |
| 2026-02-21 12:00 |
11:43:31.21 |
+01:57:29.1 |
HIP 57107 |
29.27 |
| 2026-02-22 00:00 |
11:43:17.60 |
+01:58:39.3 |
HIP 57107 |
26.49 |
| 2026-02-22 12:00 |
11:43:03.95 |
+01:59:49.7 |
HIP 57107 |
23.91 |
| 2026-02-23 00:00 |
11:42:50.26 |
+02:01:00.3 |
HIP 57107 |
21.62 |
| 2026-02-23 12:00 |
11:42:36.53 |
+02:02:11.2 |
HIP 57107 |
19.74 |
| 2026-02-24 00:00 |
11:42:22.76 |
+02:03:22.3 |
HIP 57107 |
18.37 |