| Parameter |
Value |
| Designation |
C/2024 D1 (Lemmon) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2027-12-03T06:40:33.049920Z |
| Orbit solution date (soln_date, UTC) |
2026-06-09T11:12:28Z |
| Obs used |
72 |
| NEO |
- |
| M1 |
6.100 |
| K1 |
10.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-02-16T07:22:35.817600Z |
| Discovery magnitude (MPC) |
21.96 G |
| Discovery observatory (MPC) |
G96 · University of Arizona Mt. Lemmon Survey |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-10-07.0000000 |
| e |
0.99894213 |
| q (au) |
6.696186 |
| a (au) |
6329.900246 |
| i (deg) |
132.456254 |
| Ω (om, deg) |
179.676744 |
| ω (w, deg) |
125.753045 |
| M (ma, deg) |
359.997745 |
Magnitude
Scatter + Global Linear
$$
M_a = (3.802 + 4.676\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
3.802 |
| n |
4.676 |
| gf |
0.997 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.995 |
| 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) |
| 2026-09-25 00:00 |
06:59:41.76 |
+70:33:26.1 |
HIP 33827 |
17.17 |
| 2026-09-25 12:00 |
06:59:28.36 |
+70:36:48.9 |
HIP 33827 |
14.96 |
| 2026-09-26 00:00 |
06:59:14.45 |
+70:40:12.5 |
HIP 33827 |
13.36 |
| 2026-09-26 12:00 |
06:59:00.01 |
+70:43:36.8 |
HIP 33573 |
11.42 |
| 2026-09-27 00:00 |
06:58:45.06 |
+70:47:02.0 |
HIP 33573 |
7.86 |
| 2026-09-27 12:00 |
06:58:29.57 |
+70:50:27.9 |
HIP 33573 |
4.41 |
| 2026-09-28 00:00 |
06:58:13.55 |
+70:53:54.5 |
HIP 33573 |
2.00 |
| 2026-09-28 12:00 |
06:57:56.97 |
+70:57:21.9 |
HIP 33573 |
4.00 |
| 2026-09-29 00:00 |
06:57:39.85 |
+71:00:50.0 |
HIP 33573 |
7.49 |
| 2026-09-29 12:00 |
06:57:22.16 |
+71:04:18.8 |
HIP 33573 |
11.17 |
| 2026-09-30 00:00 |
06:57:03.91 |
+71:07:48.2 |
HIP 33573 |
14.93 |
| 2026-09-30 12:00 |
06:56:45.08 |
+71:11:18.3 |
HIP 33573 |
18.72 |
| 2026-10-01 00:00 |
06:56:25.66 |
+71:14:49.0 |
HIP 33573 |
22.56 |
| 2026-10-01 12:00 |
06:56:05.65 |
+71:18:20.3 |
HIP 33573 |
26.42 |
| 2026-10-02 00:00 |
06:55:45.05 |
+71:21:52.3 |
HIP 33573 |
30.32 |
| 2026-10-02 12:00 |
06:55:23.83 |
+71:25:24.7 |
HIP 33335 |
27.69 |
| 2026-10-03 00:00 |
06:55:01.99 |
+71:28:57.8 |
HIP 33335 |
24.41 |
| 2026-10-03 12:00 |
06:54:39.53 |
+71:32:31.3 |
HIP 33335 |
21.36 |
| 2026-10-04 00:00 |
06:54:16.44 |
+71:36:05.3 |
HIP 33335 |
18.68 |
| 2026-10-04 12:00 |
06:53:52.70 |
+71:39:39.9 |
HIP 33335 |
16.55 |
| 2026-10-05 00:00 |
06:53:28.30 |
+71:43:14.8 |
HIP 33335 |
15.24 |
| 2026-10-05 12:00 |
06:53:03.25 |
+71:46:50.2 |
HIP 33335 |
14.98 |
| 2026-10-06 00:00 |
06:52:37.53 |
+71:50:25.9 |
HIP 33335 |
15.85 |
| 2026-10-06 12:00 |
06:52:11.13 |
+71:54:02.1 |
HIP 33335 |
17.71 |
| 2026-10-07 00:00 |
06:51:44.04 |
+71:57:38.5 |
HIP 33335 |
20.29 |
| 2026-10-07 12:00 |
06:51:16.26 |
+72:01:15.3 |
HIP 33335 |
23.39 |
| 2026-10-08 00:00 |
06:50:47.77 |
+72:04:52.3 |
HIP 33335 |
26.82 |
| 2026-10-08 12:00 |
06:50:18.57 |
+72:08:29.6 |
HIP 32313 |
29.82 |
| 2026-10-09 00:00 |
06:49:48.64 |
+72:12:07.1 |
HIP 32704 |
29.36 |
| 2026-10-09 12:00 |
06:49:17.98 |
+72:15:44.7 |
HIP 32704 |
25.67 |
| 2026-10-10 00:00 |
06:48:46.58 |
+72:19:22.5 |
HIP 32704 |
22.21 |
| 2026-10-10 12:00 |
06:48:14.43 |
+72:23:00.4 |
HIP 32704 |
19.12 |
| 2026-10-11 00:00 |
06:47:41.52 |
+72:26:38.4 |
HIP 32704 |
16.63 |
| 2026-10-11 12:00 |
06:47:07.84 |
+72:30:16.4 |
HIP 32534 |
12.98 |
| 2026-10-12 00:00 |
06:46:33.38 |
+72:33:54.4 |
HIP 32534 |
9.94 |
| 2026-10-12 12:00 |
06:45:58.13 |
+72:37:32.4 |
HIP 32534 |
8.33 |
| 2026-10-13 00:00 |
06:45:22.09 |
+72:41:10.3 |
HIP 32534 |
8.99 |
| 2026-10-13 12:00 |
06:44:45.24 |
+72:44:48.1 |
HIP 32534 |
11.58 |
| 2026-10-14 00:00 |
06:44:07.58 |
+72:48:25.7 |
HIP 32534 |
15.17 |
| 2026-10-14 12:00 |
06:43:29.10 |
+72:52:03.1 |
HIP 32534 |
19.22 |
| 2026-10-15 00:00 |
06:42:49.78 |
+72:55:40.3 |
HIP 31723 |
21.01 |
| 2026-10-15 12:00 |
06:42:09.63 |
+72:59:17.3 |
HIP 31723 |
19.35 |
| 2026-10-16 00:00 |
06:41:28.62 |
+73:02:53.9 |
HIP 31723 |
18.70 |