C/2023 TD22 (Lemmon)

Metadata

Parameter Value
Designation C/2023 TD22 (Lemmon)
Type C
Perihelion (tp_cal, UTC) 2024-09-16T06:57:35.680320Z
Orbit solution date (soln_date, UTC) 2026-04-27T13:42:20Z
Obs used 613
NEO -
M1 12.800
K1 9.250
PC 0.030
Osculating Elements
Parameter Value
Epoch (epoch_cal, TDB) 2024-08-15.0000000
e 0.95098531
q (au) 2.356801
a (au) 48.083568
i (deg) 170.489642
Ω (om, deg) 5.555951
ω (w, deg) 32.533345
M (ma, deg) 359.904550

Magnitude

C/2023 TD22 (Lemmon) · Magnitude (Full range)

Scatter + Global Linear

$$ M_a = (13.563 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

Model Parameters

Parameter Value
H0 13.563
n 2.000
gf 0.959
gb -1.000
k 1.000
δ90 3.114
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

Ephemeris

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-09-20 00:00 14:20:16.70 -08:42:17.8 HIP 70060 1.07
2026-09-20 12:00 14:20:23.79 -08:43:16.2 HIP 70060 2.94
2026-09-21 00:00 14:20:30.95 -08:44:14.7 HIP 70060 4.93
2026-09-21 12:00 14:20:38.18 -08:45:13.2 HIP 70060 6.95
2026-09-22 00:00 14:20:45.46 -08:46:11.9 HIP 70060 8.99
2026-09-22 12:00 14:20:52.81 -08:47:10.7 HIP 70060 11.05
2026-09-23 00:00 14:21:00.21 -08:48:09.6 HIP 70060 13.12
2026-09-23 12:00 14:21:07.67 -08:49:08.6 HIP 70060 15.21
2026-09-24 00:00 14:21:15.19 -08:50:07.8 HIP 70060 17.31
2026-09-24 12:00 14:21:22.77 -08:51:07.0 HIP 70060 19.42
2026-09-25 00:00 14:21:30.40 -08:52:06.2 HIP 70060 21.55
2026-09-25 12:00 14:21:38.09 -08:53:05.6 HIP 70302 21.27
2026-09-26 00:00 14:21:45.84 -08:54:05.1 HIP 70302 19.23
2026-09-26 12:00 14:21:53.63 -08:55:04.6 HIP 70302 17.21
2026-09-27 00:00 14:22:01.48 -08:56:04.2 HIP 70302 15.20
2026-09-27 12:00 14:22:09.39 -08:57:03.9 HIP 70302 13.24
2026-09-28 00:00 14:22:17.34 -08:58:03.6 HIP 70302 11.36
2026-09-28 12:00 14:22:25.35 -08:59:03.4 HIP 70302 9.60
2026-09-29 00:00 14:22:33.40 -09:00:03.3 HIP 70302 8.05
2026-09-29 12:00 14:22:41.51 -09:01:03.2 HIP 70302 6.88
2026-09-30 00:00 14:22:49.66 -09:02:03.1 HIP 70302 6.30
2026-09-30 12:00 14:22:57.87 -09:03:03.2 HIP 70302 6.50
2026-10-01 00:00 14:23:06.12 -09:04:03.2 HIP 70302 7.42
2026-10-01 12:00 14:23:14.41 -09:05:03.3 HIP 70302 8.84
2026-10-02 00:00 14:23:22.75 -09:06:03.4 HIP 70302 10.57
2026-10-02 12:00 14:23:31.14 -09:07:03.6 HIP 70302 12.49
2026-10-03 00:00 14:23:39.57 -09:08:03.8 HIP 70302 14.53
2026-10-03 12:00 14:23:48.05 -09:09:04.0 HIP 70302 16.65
2026-10-04 00:00 14:23:56.57 -09:10:04.3 HIP 70302 18.82
2026-10-04 12:00 14:24:05.13 -09:11:04.5 HIP 70302 21.04
2026-10-05 00:00 14:24:13.73 -09:12:04.8 HIP 70302 23.28
2026-10-05 12:00 14:24:22.38 -09:13:05.1 HIP 70302 25.56
2026-10-06 00:00 14:24:31.06 -09:14:05.3 HIP 70302 27.85
2026-10-06 12:00 14:24:39.78 -09:15:05.6 HIP 70302 30.16
2026-10-07 00:00 14:24:48.54 -09:16:05.9 HIP 70302 32.49
2026-10-07 12:00 14:24:57.34 -09:17:06.2 HIP 70302 34.84
2026-10-08 00:00 14:25:06.17 -09:18:06.4 HIP 70302 37.20
2026-10-08 12:00 14:25:15.04 -09:19:06.6 HIP 70302 39.57
2026-10-09 00:00 14:25:23.95 -09:20:06.9 HIP 70302 41.95
2026-10-09 12:00 14:25:32.89 -09:21:07.0 HIP 70302 44.34
2026-10-10 00:00 14:25:41.86 -09:22:07.2 HIP 70302 46.74
2026-10-10 12:00 14:25:50.87 -09:23:07.3 HIP 70302 49.15
2026-10-11 00:00 14:25:59.90 -09:24:07.4 HIP 70752 50.31