P/2024 S2 (Rankin)
| Parameter |
Value |
| Designation |
P/2024 S2 (Rankin) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2024-09-16T12:34:51.294720Z |
| Orbit solution date (soln_date, UTC) |
2025-01-13T08:43:47Z |
| Obs used |
154 |
| NEO |
- |
| M1 |
14.700 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2024-09-30T10:08:03.696000Z |
| Discovery magnitude (MPC) |
17.60 G |
| Discovery observatory (MPC) |
V11 · Saguaro Observatory, Tucson |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-10-04.0000000 |
| e |
0.59215299 |
| q (au) |
2.047742 |
| a (au) |
5.020858 |
| i (deg) |
7.523796 |
| Ω (om, deg) |
8.352672 |
| ω (w, deg) |
49.240931 |
| M (ma, deg) |
1.530996 |
Magnitude
Scatter + Global Linear
$$
M_a = (12.271 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
12.271 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.501 |
| k |
1.000 |
| δ90 |
10.000 |
| 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) |
| 2026-02-03 00:00 |
12:14:17.70 |
+01:02:48.3 |
HIP 59771 |
31.31 |
| 2026-02-03 12:00 |
12:14:08.23 |
+01:03:36.5 |
HIP 59500 |
30.79 |
| 2026-02-04 00:00 |
12:13:58.55 |
+01:04:26.0 |
HIP 59500 |
28.25 |
| 2026-02-04 12:00 |
12:13:48.65 |
+01:05:16.6 |
HIP 59500 |
25.65 |
| 2026-02-05 00:00 |
12:13:38.54 |
+01:06:08.6 |
HIP 59500 |
23.01 |
| 2026-02-05 12:00 |
12:13:28.21 |
+01:07:01.7 |
HIP 59500 |
20.32 |
| 2026-02-06 00:00 |
12:13:17.68 |
+01:07:56.0 |
HIP 59500 |
17.58 |
| 2026-02-06 12:00 |
12:13:06.94 |
+01:08:51.6 |
HIP 59500 |
14.81 |
| 2026-02-07 00:00 |
12:12:55.98 |
+01:09:48.3 |
HIP 59500 |
12.02 |
| 2026-02-07 12:00 |
12:12:44.83 |
+01:10:46.2 |
HIP 59500 |
9.25 |
| 2026-02-08 00:00 |
12:12:33.46 |
+01:11:45.3 |
HIP 59500 |
6.58 |
| 2026-02-08 12:00 |
12:12:21.90 |
+01:12:45.6 |
HIP 59500 |
4.34 |
| 2026-02-09 00:00 |
12:12:10.13 |
+01:13:47.0 |
HIP 59500 |
3.64 |
| 2026-02-09 12:00 |
12:11:58.16 |
+01:14:49.5 |
HIP 59500 |
5.24 |
| 2026-02-10 00:00 |
12:11:45.99 |
+01:15:53.1 |
HIP 59500 |
7.91 |
| 2026-02-10 12:00 |
12:11:33.63 |
+01:16:57.9 |
HIP 59500 |
10.93 |
| 2026-02-11 00:00 |
12:11:21.07 |
+01:18:03.7 |
HIP 59500 |
14.11 |
| 2026-02-11 12:00 |
12:11:08.31 |
+01:19:10.7 |
HIP 59500 |
17.40 |
| 2026-02-12 00:00 |
12:10:55.37 |
+01:20:18.7 |
HIP 59500 |
20.77 |
| 2026-02-12 12:00 |
12:10:42.23 |
+01:21:27.8 |
HIP 59500 |
24.20 |
| 2026-02-13 00:00 |
12:10:28.91 |
+01:22:37.9 |
HIP 59500 |
27.70 |
| 2026-02-13 12:00 |
12:10:15.41 |
+01:23:49.0 |
HIP 59500 |
31.25 |
| 2026-02-14 00:00 |
12:10:01.72 |
+01:25:01.2 |
HIP 59285 |
29.33 |
| 2026-02-14 12:00 |
12:09:47.85 |
+01:26:14.3 |
HIP 59285 |
27.71 |
| 2026-02-15 00:00 |
12:09:33.80 |
+01:27:28.4 |
HIP 59285 |
26.49 |
| 2026-02-15 12:00 |
12:09:19.57 |
+01:28:43.5 |
HIP 59285 |
25.75 |
| 2026-02-16 00:00 |
12:09:05.17 |
+01:29:59.6 |
HIP 59145 |
22.11 |
| 2026-02-16 12:00 |
12:08:50.60 |
+01:31:16.6 |
HIP 59145 |
18.26 |
| 2026-02-17 00:00 |
12:08:35.86 |
+01:32:34.5 |
HIP 59145 |
14.36 |
| 2026-02-17 12:00 |
12:08:20.95 |
+01:33:53.3 |
HIP 59145 |
10.43 |
| 2026-02-18 00:00 |
12:08:05.88 |
+01:35:13.0 |
HIP 59145 |
6.49 |
| 2026-02-18 12:00 |
12:07:50.65 |
+01:36:33.5 |
HIP 59145 |
2.64 |
| 2026-02-19 00:00 |
12:07:35.26 |
+01:37:54.9 |
HIP 59145 |
2.15 |
| 2026-02-19 12:00 |
12:07:19.71 |
+01:39:17.1 |
HIP 59145 |
6.00 |
| 2026-02-20 00:00 |
12:07:04.01 |
+01:40:40.2 |
HIP 59145 |
10.11 |
| 2026-02-20 12:00 |
12:06:48.16 |
+01:42:04.0 |
HIP 59145 |
14.28 |
| 2026-02-21 00:00 |
12:06:32.16 |
+01:43:28.6 |
HIP 59145 |
18.51 |
| 2026-02-21 12:00 |
12:06:16.02 |
+01:44:53.9 |
HIP 59145 |
22.78 |
| 2026-02-22 00:00 |
12:05:59.74 |
+01:46:20.0 |
HIP 59145 |
27.09 |
| 2026-02-22 12:00 |
12:05:43.31 |
+01:47:46.7 |
HIP 58944 |
24.61 |
| 2026-02-23 00:00 |
12:05:26.75 |
+01:49:14.2 |
HIP 58944 |
22.14 |
| 2026-02-23 12:00 |
12:05:10.06 |
+01:50:42.3 |
HIP 58944 |
20.31 |
| 2026-02-24 00:00 |
12:04:53.25 |
+01:52:11.1 |
HIP 58944 |
19.33 |