C/2022 E2 (ATLAS)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2022 E2 (ATLAS) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2024-09-14T02:57:25.395840Z |
| Orbit solution date (soln_date, UTC) | 2026-05-05T09:12:15Z |
| Obs used | 5563 |
| NEO | - |
| M1 | 8.400 |
| K1 | 5.750 |
| PC | - |
| Discovery observation (MPC, UTC) | 2022-03-07T02:52:22.339200Z |
| Discovery magnitude (MPC) | 18.76 c |
| Discovery observatory (MPC) | W68 · ATLAS Chile, Rio Hurtado |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2024-07-19.0000000 |
| e | 1.00094336 |
| q (au) | 3.666303 |
| a (au) | -3886.442244 |
| i (deg) | 137.127877 |
| Ω (om, deg) | 125.372051 |
| ω (w, deg) | 41.720283 |
| M (ma, deg) | -0.000232 |
Magnitude
Scatter + Global Linear
$$ M_a = (6.610 + 3.024\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 6.610 |
| n | 3.024 |
| gf | 0.999 |
| gb | -0.872 |
| k | 0.999 |
| 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 |
|---|---|---|---|
| 2022-02-23 | 2024-01-05 | +2.2356 | -1.999 |
| 2024-01-05 | 2024-09-14 | +6.6644 | -4.398 |
| 2024-09-15 | 2026-05-15 | +3.9923 | -2.465 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 23:14:37.37 | +30:23:20.3 | HIP 114886 | 27.44 |
| 2026-05-12 12:00 | 23:14:39.19 | +30:24:45.2 | HIP 114886 | 26.28 |
| 2026-05-13 00:00 | 23:14:40.87 | +30:26:10.1 | HIP 114886 | 25.17 |
| 2026-05-13 12:00 | 23:14:42.41 | +30:27:35.0 | HIP 114886 | 24.12 |
| 2026-05-14 00:00 | 23:14:43.81 | +30:28:59.9 | HIP 114886 | 23.15 |
| 2026-05-14 12:00 | 23:14:45.08 | +30:30:24.7 | HIP 114886 | 22.25 |
| 2026-05-15 00:00 | 23:14:46.20 | +30:31:49.5 | HIP 114886 | 21.44 |
| 2026-05-15 12:00 | 23:14:47.18 | +30:33:14.3 | HIP 114886 | 20.73 |
| 2026-05-16 00:00 | 23:14:48.02 | +30:34:39.0 | HIP 114886 | 20.12 |
| 2026-05-16 12:00 | 23:14:48.71 | +30:36:03.6 | HIP 114886 | 19.63 |
| 2026-05-17 00:00 | 23:14:49.26 | +30:37:28.1 | HIP 114886 | 19.26 |
| 2026-05-17 12:00 | 23:14:49.66 | +30:38:52.5 | HIP 114886 | 19.03 |
| 2026-05-18 00:00 | 23:14:49.92 | +30:40:16.8 | HIP 114886 | 18.92 |
| 2026-05-18 12:00 | 23:14:50.03 | +30:41:41.0 | HIP 114886 | 18.95 |
| 2026-05-19 00:00 | 23:14:49.99 | +30:43:05.1 | HIP 114886 | 19.12 |
| 2026-05-19 12:00 | 23:14:49.81 | +30:44:29.0 | HIP 114886 | 19.42 |
| 2026-05-20 00:00 | 23:14:49.48 | +30:45:52.7 | HIP 114886 | 19.84 |
| 2026-05-20 12:00 | 23:14:48.99 | +30:47:16.3 | HIP 114886 | 20.38 |
| 2026-05-21 00:00 | 23:14:48.36 | +30:48:39.7 | HIP 114886 | 21.02 |
| 2026-05-21 12:00 | 23:14:47.57 | +30:50:02.9 | HIP 114886 | 21.76 |
| 2026-05-22 00:00 | 23:14:46.64 | +30:51:25.8 | HIP 114886 | 22.60 |
| 2026-05-22 12:00 | 23:14:45.55 | +30:52:48.6 | HIP 114886 | 23.51 |
| 2026-05-23 00:00 | 23:14:44.31 | +30:54:11.2 | HIP 114886 | 24.49 |
| 2026-05-23 12:00 | 23:14:42.92 | +30:55:33.5 | HIP 114886 | 25.54 |
| 2026-05-24 00:00 | 23:14:41.37 | +30:56:55.5 | HIP 114886 | 26.64 |
| 2026-05-24 12:00 | 23:14:39.66 | +30:58:17.3 | HIP 114886 | 27.79 |
| 2026-05-25 00:00 | 23:14:37.81 | +30:59:38.8 | HIP 114886 | 28.98 |
| 2026-05-25 12:00 | 23:14:35.79 | +31:01:00.1 | HIP 114886 | 30.22 |
| 2026-05-26 00:00 | 23:14:33.62 | +31:02:21.0 | HIP 114886 | 31.49 |
| 2026-05-26 12:00 | 23:14:31.30 | +31:03:41.7 | HIP 114886 | 32.79 |
| 2026-05-27 00:00 | 23:14:28.81 | +31:05:02.0 | HIP 114886 | 34.13 |
| 2026-05-27 12:00 | 23:14:26.17 | +31:06:22.0 | HIP 114886 | 35.49 |
| 2026-05-28 00:00 | 23:14:23.37 | +31:07:41.7 | HIP 114838 | 36.83 |
| 2026-05-28 12:00 | 23:14:20.41 | +31:09:01.0 | HIP 114838 | 35.96 |
| 2026-05-29 00:00 | 23:14:17.29 | +31:10:19.9 | HIP 114838 | 35.14 |
| 2026-05-29 12:00 | 23:14:14.01 | +31:11:38.5 | HIP 114838 | 34.40 |
| 2026-05-30 00:00 | 23:14:10.57 | +31:12:56.7 | HIP 114838 | 33.73 |
| 2026-05-30 12:00 | 23:14:06.97 | +31:14:14.5 | HIP 114838 | 33.14 |
| 2026-05-31 00:00 | 23:14:03.21 | +31:15:31.9 | HIP 114838 | 32.63 |
| 2026-05-31 12:00 | 23:13:59.28 | +31:16:48.9 | HIP 114838 | 32.22 |
| 2026-06-01 00:00 | 23:13:55.19 | +31:18:05.5 | HIP 114838 | 31.90 |
| 2026-06-01 12:00 | 23:13:50.94 | +31:19:21.6 | HIP 114838 | 31.69 |
| 2026-06-02 00:00 | 23:13:46.53 | +31:20:37.3 | HIP 114838 | 31.58 |