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) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 19:28:07.97 | -00:01:26.5 | HIP 95715 | 23.70 |
| 2026-09-20 12:00 | 19:28:07.23 | -00:02:29.1 | HIP 95715 | 22.65 |
| 2026-09-21 00:00 | 19:28:06.61 | -00:03:31.7 | HIP 95715 | 21.60 |
| 2026-09-21 12:00 | 19:28:06.10 | -00:04:34.0 | HIP 95715 | 20.56 |
| 2026-09-22 00:00 | 19:28:05.71 | -00:05:36.3 | HIP 95715 | 19.53 |
| 2026-09-22 12:00 | 19:28:05.43 | -00:06:38.4 | HIP 95715 | 18.49 |
| 2026-09-23 00:00 | 19:28:05.27 | -00:07:40.3 | HIP 95715 | 17.46 |
| 2026-09-23 12:00 | 19:28:05.22 | -00:08:42.1 | HIP 95715 | 16.43 |
| 2026-09-24 00:00 | 19:28:05.29 | -00:09:43.7 | HIP 95715 | 15.40 |
| 2026-09-24 12:00 | 19:28:05.48 | -00:10:45.2 | HIP 95715 | 14.38 |
| 2026-09-25 00:00 | 19:28:05.78 | -00:11:46.5 | HIP 95715 | 13.36 |
| 2026-09-25 12:00 | 19:28:06.19 | -00:12:47.6 | HIP 95715 | 12.34 |
| 2026-09-26 00:00 | 19:28:06.72 | -00:13:48.5 | HIP 95715 | 11.32 |
| 2026-09-26 12:00 | 19:28:07.37 | -00:14:49.2 | HIP 95715 | 10.32 |
| 2026-09-27 00:00 | 19:28:08.13 | -00:15:49.8 | HIP 95715 | 9.32 |
| 2026-09-27 12:00 | 19:28:09.00 | -00:16:50.1 | HIP 95715 | 8.34 |
| 2026-09-28 00:00 | 19:28:09.99 | -00:17:50.2 | HIP 95715 | 7.37 |
| 2026-09-28 12:00 | 19:28:11.09 | -00:18:50.1 | HIP 95715 | 6.43 |
| 2026-09-29 00:00 | 19:28:12.31 | -00:19:49.8 | HIP 95715 | 5.55 |
| 2026-09-29 12:00 | 19:28:13.64 | -00:20:49.3 | HIP 95715 | 4.74 |
| 2026-09-30 00:00 | 19:28:15.08 | -00:21:48.5 | HIP 95715 | 4.06 |
| 2026-09-30 12:00 | 19:28:16.64 | -00:22:47.5 | HIP 95715 | 3.59 |
| 2026-10-01 00:00 | 19:28:18.31 | -00:23:46.3 | HIP 95715 | 3.42 |
| 2026-10-01 12:00 | 19:28:20.10 | -00:24:44.8 | HIP 95715 | 3.60 |
| 2026-10-02 00:00 | 19:28:22.00 | -00:25:43.1 | HIP 95715 | 4.10 |
| 2026-10-02 12:00 | 19:28:24.01 | -00:26:41.1 | HIP 95715 | 4.82 |
| 2026-10-03 00:00 | 19:28:26.14 | -00:27:38.8 | HIP 95715 | 5.68 |
| 2026-10-03 12:00 | 19:28:28.37 | -00:28:36.3 | HIP 95715 | 6.63 |
| 2026-10-04 00:00 | 19:28:30.73 | -00:29:33.5 | HIP 95715 | 7.65 |
| 2026-10-04 12:00 | 19:28:33.19 | -00:30:30.4 | HIP 95715 | 8.71 |
| 2026-10-05 00:00 | 19:28:35.77 | -00:31:27.1 | HIP 95715 | 9.81 |
| 2026-10-05 12:00 | 19:28:38.46 | -00:32:23.4 | HIP 95715 | 10.93 |
| 2026-10-06 00:00 | 19:28:41.26 | -00:33:19.5 | HIP 95715 | 12.08 |
| 2026-10-06 12:00 | 19:28:44.17 | -00:34:15.3 | HIP 95715 | 13.24 |
| 2026-10-07 00:00 | 19:28:47.19 | -00:35:10.7 | HIP 95715 | 14.43 |
| 2026-10-07 12:00 | 19:28:50.33 | -00:36:05.9 | HIP 95715 | 15.63 |
| 2026-10-08 00:00 | 19:28:53.58 | -00:37:00.7 | HIP 95715 | 16.85 |
| 2026-10-08 12:00 | 19:28:56.94 | -00:37:55.2 | HIP 95715 | 18.09 |
| 2026-10-09 00:00 | 19:29:00.41 | -00:38:49.4 | HIP 95715 | 19.34 |
| 2026-10-09 12:00 | 19:29:03.99 | -00:39:43.2 | HIP 95886 | 20.00 |
| 2026-10-10 00:00 | 19:29:07.68 | -00:40:36.7 | HIP 95886 | 19.92 |
| 2026-10-10 12:00 | 19:29:11.48 | -00:41:29.9 | HIP 95886 | 19.90 |
| 2026-10-11 00:00 | 19:29:15.39 | -00:42:22.7 | HIP 95886 | 19.95 |