C/2024 D1 (Lemmon)
| Parameter |
Value |
| Designation |
C/2024 D1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2027-12-03T05:29:55.415040Z |
| Orbit solution date (soln_date, UTC) |
2026-01-13T08:12:18Z |
| Obs used |
61 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
6.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-02-16T07:22:35.817600Z |
| Discovery magnitude (MPC) |
21.96 G |
| Discovery observatory (MPC) |
G96 · Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-09-09.0000000 |
| e |
0.99899109 |
| q (au) |
6.696522 |
| a (au) |
6637.408819 |
| i (deg) |
132.456969 |
| Ω (om, deg) |
179.678196 |
| ω (w, deg) |
125.749232 |
| M (ma, deg) |
359.997849 |
Magnitude
Scatter + Global Linear
$$
M_a = (2.228 + 5.319\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
2.228 |
| n |
5.319 |
| gf |
0.924 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
8.533 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
07:43:24.01 |
+73:26:30.5 |
HIP 37205 |
22.58 |
| 2026-02-03 12:00 |
07:42:07.74 |
+73:26:39.3 |
HIP 37205 |
17.70 |
| 2026-02-04 00:00 |
07:40:51.66 |
+73:26:44.9 |
HIP 37205 |
13.30 |
| 2026-02-04 12:00 |
07:39:35.78 |
+73:26:47.0 |
HIP 37205 |
10.00 |
| 2026-02-05 00:00 |
07:38:20.11 |
+73:26:45.9 |
HIP 37205 |
9.04 |
| 2026-02-05 12:00 |
07:37:04.67 |
+73:26:41.4 |
HIP 37205 |
11.05 |
| 2026-02-06 00:00 |
07:35:49.48 |
+73:26:33.7 |
HIP 36954 |
10.05 |
| 2026-02-06 12:00 |
07:34:34.55 |
+73:26:22.7 |
HIP 36954 |
11.27 |
| 2026-02-07 00:00 |
07:33:19.89 |
+73:26:08.4 |
HIP 36954 |
14.46 |
| 2026-02-07 12:00 |
07:32:05.52 |
+73:25:50.9 |
HIP 36954 |
18.62 |
| 2026-02-08 00:00 |
07:30:51.46 |
+73:25:30.3 |
HIP 36954 |
23.23 |
| 2026-02-08 12:00 |
07:29:37.71 |
+73:25:06.4 |
HIP 36142 |
23.74 |
| 2026-02-09 00:00 |
07:28:24.30 |
+73:24:39.5 |
HIP 36142 |
20.97 |
| 2026-02-09 12:00 |
07:27:11.23 |
+73:24:09.4 |
HIP 36142 |
19.25 |
| 2026-02-10 00:00 |
07:25:58.52 |
+73:23:36.2 |
HIP 36132 |
18.83 |
| 2026-02-10 12:00 |
07:24:46.19 |
+73:23:00.0 |
HIP 36132 |
19.68 |
| 2026-02-11 00:00 |
07:23:34.24 |
+73:22:20.7 |
HIP 35557 |
18.00 |
| 2026-02-11 12:00 |
07:22:22.69 |
+73:21:38.5 |
HIP 35557 |
14.86 |
| 2026-02-12 00:00 |
07:21:11.56 |
+73:20:53.2 |
HIP 35557 |
13.10 |
| 2026-02-12 12:00 |
07:20:00.85 |
+73:20:05.1 |
HIP 35557 |
13.27 |
| 2026-02-13 00:00 |
07:18:50.57 |
+73:19:14.0 |
HIP 35197 |
10.48 |
| 2026-02-13 12:00 |
07:17:40.74 |
+73:18:20.1 |
HIP 35197 |
5.69 |
| 2026-02-14 00:00 |
07:16:31.37 |
+73:17:23.3 |
HIP 35197 |
2.61 |
| 2026-02-14 12:00 |
07:15:22.47 |
+73:16:23.8 |
HIP 35157 |
3.99 |
| 2026-02-15 00:00 |
07:14:14.05 |
+73:15:21.4 |
HIP 35157 |
8.58 |
| 2026-02-15 12:00 |
07:13:06.12 |
+73:14:16.4 |
HIP 35157 |
13.48 |
| 2026-02-16 00:00 |
07:11:58.69 |
+73:13:08.7 |
HIP 35157 |
18.43 |
| 2026-02-16 12:00 |
07:10:51.78 |
+73:11:58.3 |
HIP 35157 |
23.37 |
| 2026-02-17 00:00 |
07:09:45.38 |
+73:10:45.2 |
HIP 34124 |
26.95 |
| 2026-02-17 12:00 |
07:08:39.51 |
+73:09:29.7 |
HIP 34124 |
24.00 |
| 2026-02-18 00:00 |
07:07:34.18 |
+73:08:11.5 |
HIP 34124 |
21.81 |
| 2026-02-18 12:00 |
07:06:29.40 |
+73:06:50.9 |
HIP 34124 |
20.61 |
| 2026-02-19 00:00 |
07:05:25.16 |
+73:05:27.9 |
HIP 34014 |
18.87 |
| 2026-02-19 12:00 |
07:04:21.50 |
+73:04:02.4 |
HIP 34014 |
15.90 |
| 2026-02-20 00:00 |
07:03:18.40 |
+73:02:34.5 |
HIP 34014 |
13.99 |
| 2026-02-20 12:00 |
07:02:15.87 |
+73:01:04.3 |
HIP 34014 |
13.59 |
| 2026-02-21 00:00 |
07:01:13.93 |
+72:59:31.8 |
HIP 34014 |
14.79 |
| 2026-02-21 12:00 |
07:00:12.57 |
+72:57:57.1 |
HIP 34014 |
17.24 |
| 2026-02-22 00:00 |
06:59:11.81 |
+72:56:20.1 |
HIP 33589 |
17.89 |
| 2026-02-22 12:00 |
06:58:11.65 |
+72:54:41.0 |
HIP 33589 |
16.25 |
| 2026-02-23 00:00 |
06:57:12.09 |
+72:52:59.7 |
HIP 33589 |
15.86 |
| 2026-02-23 12:00 |
06:56:13.14 |
+72:51:16.4 |
HIP 33589 |
16.79 |
| 2026-02-24 00:00 |
06:55:14.81 |
+72:49:31.0 |
HIP 33589 |
18.83 |