| Parameter |
Value |
| Designation |
C/2022 R2 (ATLAS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-10-25T05:16:07.564800Z |
| Orbit solution date (soln_date, UTC) |
2025-01-14T17:42:12Z |
| Obs used |
295 |
| NEO |
- |
| M1 |
16.600 |
| K1 |
16.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2022-09-14T14:22:04.569600Z |
| Discovery magnitude (MPC) |
17.63 o |
| Discovery observatory (MPC) |
T08 · ATLAS-MLO, Mauna Loa |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-09-29.0000000 |
| e |
0.99850301 |
| q (au) |
0.632587 |
| a (au) |
422.571115 |
| i (deg) |
52.894812 |
| Ω (om, deg) |
60.403612 |
| ω (w, deg) |
78.376566 |
| M (ma, deg) |
359.997025 |
Magnitude
Scatter + Global Linear
$$
M_a = (15.906 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
15.906 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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 |
| 2022-09-06 |
2022-09-18 |
-9.2857 |
+0.236 |
| 2022-09-18 |
2022-10-04 |
+15.1692 |
+0.457 |
| 2022-10-04 |
2022-10-22 |
-10.7635 |
-2.029 |
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 |
19:23:06.33 |
-64:35:16.2 |
HIP 95567 |
41.98 |
| 2026-06-01 12:00 |
19:22:50.23 |
-64:36:34.5 |
HIP 95567 |
41.74 |
| 2026-06-02 00:00 |
19:22:33.99 |
-64:37:52.2 |
HIP 95567 |
41.62 |
| 2026-06-02 12:00 |
19:22:17.61 |
-64:39:09.1 |
HIP 94693 |
40.99 |
| 2026-06-03 00:00 |
19:22:01.08 |
-64:40:25.4 |
HIP 94693 |
38.96 |
| 2026-06-03 12:00 |
19:21:44.41 |
-64:41:40.9 |
HIP 94693 |
36.94 |
| 2026-06-04 00:00 |
19:21:27.61 |
-64:42:55.7 |
HIP 94693 |
34.93 |
| 2026-06-04 12:00 |
19:21:10.66 |
-64:44:09.8 |
HIP 94693 |
32.93 |
| 2026-06-05 00:00 |
19:20:53.58 |
-64:45:23.1 |
HIP 94693 |
30.94 |
| 2026-06-05 12:00 |
19:20:36.37 |
-64:46:35.7 |
HIP 94693 |
28.97 |
| 2026-06-06 00:00 |
19:20:19.02 |
-64:47:47.6 |
HIP 94693 |
27.03 |
| 2026-06-06 12:00 |
19:20:01.54 |
-64:48:58.7 |
HIP 94693 |
25.12 |
| 2026-06-07 00:00 |
19:19:43.93 |
-64:50:09.0 |
HIP 94693 |
23.25 |
| 2026-06-07 12:00 |
19:19:26.20 |
-64:51:18.5 |
HIP 94693 |
21.43 |
| 2026-06-08 00:00 |
19:19:08.33 |
-64:52:27.2 |
HIP 94693 |
19.69 |
| 2026-06-08 12:00 |
19:18:50.35 |
-64:53:35.2 |
HIP 94693 |
18.03 |
| 2026-06-09 00:00 |
19:18:32.23 |
-64:54:42.3 |
HIP 94693 |
16.49 |
| 2026-06-09 12:00 |
19:18:14.00 |
-64:55:48.7 |
HIP 94693 |
15.11 |
| 2026-06-10 00:00 |
19:17:55.65 |
-64:56:54.2 |
HIP 94693 |
13.94 |
| 2026-06-10 12:00 |
19:17:37.18 |
-64:57:58.9 |
HIP 94693 |
13.02 |
| 2026-06-11 00:00 |
19:17:18.59 |
-64:59:02.7 |
HIP 94693 |
12.44 |
| 2026-06-11 12:00 |
19:16:59.89 |
-65:00:05.7 |
HIP 94693 |
12.22 |
| 2026-06-12 00:00 |
19:16:41.08 |
-65:01:07.9 |
HIP 94693 |
12.39 |
| 2026-06-12 12:00 |
19:16:22.16 |
-65:02:09.2 |
HIP 94770 |
12.19 |
| 2026-06-13 00:00 |
19:16:03.13 |
-65:03:09.6 |
HIP 94770 |
12.11 |
| 2026-06-13 12:00 |
19:15:44.00 |
-65:04:09.1 |
HIP 94770 |
12.45 |
| 2026-06-14 00:00 |
19:15:24.76 |
-65:05:07.8 |
HIP 94770 |
13.19 |
| 2026-06-14 12:00 |
19:15:05.42 |
-65:06:05.6 |
HIP 94770 |
14.26 |
| 2026-06-15 00:00 |
19:14:45.98 |
-65:07:02.5 |
HIP 94770 |
15.60 |
| 2026-06-15 12:00 |
19:14:26.44 |
-65:07:58.5 |
HIP 94770 |
17.14 |
| 2026-06-16 00:00 |
19:14:06.81 |
-65:08:53.6 |
HIP 94770 |
18.84 |
| 2026-06-16 12:00 |
19:13:47.08 |
-65:09:47.7 |
HIP 94770 |
20.65 |
| 2026-06-17 00:00 |
19:13:27.27 |
-65:10:41.0 |
HIP 94219 |
20.07 |
| 2026-06-17 12:00 |
19:13:07.37 |
-65:11:33.3 |
HIP 94219 |
18.91 |
| 2026-06-18 00:00 |
19:12:47.38 |
-65:12:24.7 |
HIP 94219 |
17.95 |
| 2026-06-18 12:00 |
19:12:27.31 |
-65:13:15.1 |
HIP 94219 |
17.23 |
| 2026-06-19 00:00 |
19:12:07.16 |
-65:14:04.7 |
HIP 94219 |
16.76 |
| 2026-06-19 12:00 |
19:11:46.94 |
-65:14:53.2 |
HIP 94219 |
16.58 |
| 2026-06-20 00:00 |
19:11:26.63 |
-65:15:40.8 |
HIP 94219 |
16.70 |
| 2026-06-20 12:00 |
19:11:06.26 |
-65:16:27.5 |
HIP 94219 |
17.10 |
| 2026-06-21 00:00 |
19:10:45.81 |
-65:17:13.2 |
HIP 94008 |
16.73 |
| 2026-06-21 12:00 |
19:10:25.29 |
-65:17:57.9 |
HIP 94008 |
15.26 |
| 2026-06-22 00:00 |
19:10:04.71 |
-65:18:41.6 |
HIP 94008 |
13.99 |