C/2022 T1 (Lemmon)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2022 T1 (Lemmon) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2024-02-17T12:18:13.901760Z |
| Orbit solution date (soln_date, UTC) | 2024-07-22T18:42:14Z |
| Obs used | 587 |
| NEO | - |
| M1 | 13.100 |
| K1 | 4.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2022-10-03T11:55:57.561600Z |
| Discovery magnitude (MPC) | 21.24 G |
| Discovery observatory (MPC) | G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2023-10-10.0000000 |
| e | 0.99971338 |
| q (au) | 3.444855 |
| a (au) | 12018.953434 |
| i (deg) | 22.543649 |
| Ω (om, deg) | 236.919592 |
| ω (w, deg) | 324.316453 |
| M (ma, deg) | 359.999902 |
Magnitude
Scatter + Global Linear
$$ M_a = (11.928 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
Model Parameters
| Parameter | Value |
|---|---|
| H0 | 11.928 |
| n | 2.000 |
| gf | 0.991 |
| gb | -0.786 |
| k | 1.000 |
| δ90 | 9.981 |
| 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 |
|---|---|---|---|
| 2022-10-03 | 2023-01-17 | +12.9256 | -9.332 |
| 2023-01-17 | 2023-05-12 | +7.4343 | -5.338 |
| 2023-05-12 | 2024-02-14 | -1.8398 | +0.708 |
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) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 19:39:13.55 | +01:35:28.2 | HIP 96589 | 18.89 |
| 2026-07-29 12:00 | 19:39:03.13 | +01:34:55.4 | HIP 96589 | 17.13 |
| 2026-07-30 00:00 | 19:38:52.75 | +01:34:21.8 | HIP 96567 | 15.47 |
| 2026-07-30 12:00 | 19:38:42.42 | +01:33:47.6 | HIP 96567 | 12.83 |
| 2026-07-31 00:00 | 19:38:32.13 | +01:33:12.8 | HIP 96567 | 10.21 |
| 2026-07-31 12:00 | 19:38:21.90 | +01:32:37.3 | HIP 96567 | 7.60 |
| 2026-08-01 00:00 | 19:38:11.70 | +01:32:01.1 | HIP 96567 | 5.01 |
| 2026-08-01 12:00 | 19:38:01.56 | +01:31:24.3 | HIP 96567 | 2.50 |
| 2026-08-02 00:00 | 19:37:51.47 | +01:30:46.9 | HIP 96567 | 0.96 |
| 2026-08-02 12:00 | 19:37:41.43 | +01:30:08.8 | HIP 96567 | 3.00 |
| 2026-08-03 00:00 | 19:37:31.45 | +01:29:30.2 | HIP 96567 | 5.51 |
| 2026-08-03 12:00 | 19:37:21.52 | +01:28:50.9 | HIP 96567 | 8.05 |
| 2026-08-04 00:00 | 19:37:11.64 | +01:28:11.0 | HIP 96567 | 10.59 |
| 2026-08-04 12:00 | 19:37:01.82 | +01:27:30.5 | HIP 96567 | 13.12 |
| 2026-08-05 00:00 | 19:36:52.06 | +01:26:49.4 | HIP 96567 | 15.65 |
| 2026-08-05 12:00 | 19:36:42.36 | +01:26:07.7 | HIP 96567 | 18.17 |
| 2026-08-06 00:00 | 19:36:32.72 | +01:25:25.4 | HIP 96567 | 20.67 |
| 2026-08-06 12:00 | 19:36:23.14 | +01:24:42.6 | HIP 96378 | 21.43 |
| 2026-08-07 00:00 | 19:36:13.62 | +01:23:59.2 | HIP 96378 | 21.12 |
| 2026-08-07 12:00 | 19:36:04.17 | +01:23:15.2 | HIP 96378 | 21.11 |
| 2026-08-08 00:00 | 19:35:54.78 | +01:22:30.7 | HIP 96378 | 21.40 |
| 2026-08-08 12:00 | 19:35:45.46 | +01:21:45.6 | HIP 96270 | 20.03 |
| 2026-08-09 00:00 | 19:35:36.20 | +01:21:00.0 | HIP 96270 | 18.21 |
| 2026-08-09 12:00 | 19:35:27.02 | +01:20:13.8 | HIP 96270 | 16.57 |
| 2026-08-10 00:00 | 19:35:17.90 | +01:19:27.1 | HIP 96270 | 15.15 |
| 2026-08-10 12:00 | 19:35:08.85 | +01:18:39.9 | HIP 96270 | 14.03 |
| 2026-08-11 00:00 | 19:34:59.88 | +01:17:52.2 | HIP 96270 | 13.26 |
| 2026-08-11 12:00 | 19:34:50.98 | +01:17:04.0 | HIP 96270 | 12.91 |
| 2026-08-12 00:00 | 19:34:42.15 | +01:16:15.3 | HIP 96270 | 13.00 |
| 2026-08-12 12:00 | 19:34:33.40 | +01:15:26.1 | HIP 96270 | 13.51 |
| 2026-08-13 00:00 | 19:34:24.73 | +01:14:36.4 | HIP 96270 | 14.40 |
| 2026-08-13 12:00 | 19:34:16.14 | +01:13:46.2 | HIP 96270 | 15.59 |
| 2026-08-14 00:00 | 19:34:07.62 | +01:12:55.6 | HIP 96270 | 17.00 |
| 2026-08-14 12:00 | 19:33:59.18 | +01:12:04.5 | HIP 96270 | 18.59 |
| 2026-08-15 00:00 | 19:33:50.83 | +01:11:13.0 | HIP 96270 | 20.31 |
| 2026-08-15 12:00 | 19:33:42.56 | +01:10:21.1 | HIP 96270 | 22.12 |
| 2026-08-16 00:00 | 19:33:34.37 | +01:09:28.7 | HIP 96270 | 24.00 |
| 2026-08-16 12:00 | 19:33:26.26 | +01:08:35.9 | HIP 96270 | 25.92 |
| 2026-08-17 00:00 | 19:33:18.24 | +01:07:42.7 | HIP 96270 | 27.88 |
| 2026-08-17 12:00 | 19:33:10.31 | +01:06:49.1 | HIP 96270 | 29.86 |
| 2026-08-18 00:00 | 19:33:02.46 | +01:05:55.1 | HIP 96270 | 31.86 |
| 2026-08-18 12:00 | 19:32:54.70 | +01:05:00.7 | HIP 96121 | 30.66 |
| 2026-08-19 00:00 | 19:32:47.02 | +01:04:05.9 | HIP 96121 | 29.54 |