| Parameter |
Value |
| Designation |
C/2021 P1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-06-01T16:41:49.732800Z |
| Orbit solution date (soln_date, UTC) |
2024-03-19T12:12:38Z |
| Obs used |
104 |
| NEO |
- |
| M1 |
12.700 |
| K1 |
7.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-08-04T13:25:21.792000Z |
| Discovery magnitude (MPC) |
21.20 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-09-13.0000000 |
| e |
1.00024450 |
| q (au) |
4.374954 |
| a (au) |
-17893.332037 |
| i (deg) |
51.622012 |
| Ω (om, deg) |
359.671523 |
| ω (w, deg) |
40.363907 |
| M (ma, deg) |
-0.000108 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.879 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.879 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-0.791 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
11:05:43.94 |
+39:39:38.8 |
HIP 54267 |
9.19 |
| 2026-03-26 12:00 |
11:05:32.37 |
+39:39:12.9 |
HIP 54267 |
10.77 |
| 2026-03-27 00:00 |
11:05:20.86 |
+39:38:46.0 |
HIP 54267 |
12.57 |
| 2026-03-27 12:00 |
11:05:09.41 |
+39:38:18.1 |
HIP 54267 |
14.50 |
| 2026-03-28 00:00 |
11:04:58.02 |
+39:37:49.3 |
HIP 54267 |
16.52 |
| 2026-03-28 12:00 |
11:04:46.69 |
+39:37:19.5 |
HIP 54267 |
18.58 |
| 2026-03-29 00:00 |
11:04:35.43 |
+39:36:48.7 |
HIP 54267 |
20.68 |
| 2026-03-29 12:00 |
11:04:24.23 |
+39:36:16.9 |
HIP 54267 |
22.80 |
| 2026-03-30 00:00 |
11:04:13.10 |
+39:35:44.2 |
HIP 54105 |
24.56 |
| 2026-03-30 12:00 |
11:04:02.04 |
+39:35:10.6 |
HIP 54105 |
25.26 |
| 2026-03-31 00:00 |
11:03:51.04 |
+39:34:35.9 |
HIP 54105 |
26.14 |
| 2026-03-31 12:00 |
11:03:40.11 |
+39:34:00.3 |
HIP 54105 |
27.18 |
| 2026-04-01 00:00 |
11:03:29.26 |
+39:33:23.8 |
HIP 54105 |
28.36 |
| 2026-04-01 12:00 |
11:03:18.47 |
+39:32:46.3 |
HIP 54105 |
29.66 |
| 2026-04-02 00:00 |
11:03:07.75 |
+39:32:07.9 |
HIP 54105 |
31.07 |
| 2026-04-02 12:00 |
11:02:57.11 |
+39:31:28.5 |
HIP 53838 |
30.83 |
| 2026-04-03 00:00 |
11:02:46.54 |
+39:30:48.2 |
HIP 53838 |
28.81 |
| 2026-04-03 12:00 |
11:02:36.04 |
+39:30:07.0 |
HIP 53838 |
26.81 |
| 2026-04-04 00:00 |
11:02:25.62 |
+39:29:24.9 |
HIP 53838 |
24.83 |
| 2026-04-04 12:00 |
11:02:15.28 |
+39:28:41.8 |
HIP 53838 |
22.89 |
| 2026-04-05 00:00 |
11:02:05.01 |
+39:27:57.8 |
HIP 53838 |
20.97 |
| 2026-04-05 12:00 |
11:01:54.82 |
+39:27:12.8 |
HIP 53838 |
19.10 |
| 2026-04-06 00:00 |
11:01:44.71 |
+39:26:27.0 |
HIP 53838 |
17.27 |
| 2026-04-06 12:00 |
11:01:34.68 |
+39:25:40.3 |
HIP 53838 |
15.51 |
| 2026-04-07 00:00 |
11:01:24.73 |
+39:24:52.6 |
HIP 53838 |
13.84 |
| 2026-04-07 12:00 |
11:01:14.86 |
+39:24:04.1 |
HIP 53838 |
12.28 |
| 2026-04-08 00:00 |
11:01:05.07 |
+39:23:14.6 |
HIP 53838 |
10.89 |
| 2026-04-08 12:00 |
11:00:55.37 |
+39:22:24.3 |
HIP 53838 |
9.72 |
| 2026-04-09 00:00 |
11:00:45.75 |
+39:21:33.1 |
HIP 53838 |
8.87 |
| 2026-04-09 12:00 |
11:00:36.21 |
+39:20:40.9 |
HIP 53838 |
8.42 |
| 2026-04-10 00:00 |
11:00:26.76 |
+39:19:48.0 |
HIP 53838 |
8.43 |
| 2026-04-10 12:00 |
11:00:17.40 |
+39:18:54.1 |
HIP 53838 |
8.90 |
| 2026-04-11 00:00 |
11:00:08.12 |
+39:17:59.3 |
HIP 53838 |
9.74 |
| 2026-04-11 12:00 |
10:59:58.93 |
+39:17:03.7 |
HIP 53838 |
10.88 |
| 2026-04-12 00:00 |
10:59:49.82 |
+39:16:07.3 |
HIP 53838 |
12.22 |
| 2026-04-12 12:00 |
10:59:40.81 |
+39:15:09.9 |
HIP 53838 |
13.71 |
| 2026-04-13 00:00 |
10:59:31.89 |
+39:14:11.8 |
HIP 53838 |
15.29 |
| 2026-04-13 12:00 |
10:59:23.05 |
+39:13:12.7 |
HIP 53838 |
16.94 |
| 2026-04-14 00:00 |
10:59:14.31 |
+39:12:12.8 |
HIP 53620 |
15.07 |
| 2026-04-14 12:00 |
10:59:05.66 |
+39:11:12.1 |
HIP 53620 |
13.12 |
| 2026-04-15 00:00 |
10:58:57.11 |
+39:10:10.6 |
HIP 53620 |
11.18 |
| 2026-04-15 12:00 |
10:58:48.64 |
+39:09:08.2 |
HIP 53620 |
9.26 |
| 2026-04-16 00:00 |
10:58:40.27 |
+39:08:05.0 |
HIP 53620 |
7.34 |