| Parameter |
Value |
| Designation |
C/2021 A6 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-05-04T03:17:13.050240Z |
| Orbit solution date (soln_date, UTC) |
2024-08-02T01:42:19Z |
| Obs used |
167 |
| NEO |
- |
| M1 |
5.100 |
| K1 |
12.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-08T14:28:45.120000Z |
| Discovery magnitude (MPC) |
20.89 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-03-24.0000000 |
| e |
0.99923094 |
| q (au) |
7.928456 |
| a (au) |
10309.304354 |
| i (deg) |
75.612049 |
| Ω (om, deg) |
164.079307 |
| ω (w, deg) |
351.692611 |
| M (ma, deg) |
0.000305 |
Magnitude
Scatter + Global Linear
$$
M_a = (5.230 + 4.625\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
5.230 |
| n |
4.625 |
| gf |
0.981 |
| gb |
-0.874 |
| k |
1.000 |
| δ90 |
9.949 |
| 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 |
15:39:24.08 |
+53:44:51.2 |
HIP 76893 |
23.30 |
| 2026-03-26 12:00 |
15:39:19.24 |
+53:46:51.9 |
HIP 76893 |
24.19 |
| 2026-03-27 00:00 |
15:39:14.28 |
+53:48:51.9 |
HIP 76893 |
25.24 |
| 2026-03-27 12:00 |
15:39:09.21 |
+53:50:51.2 |
HIP 76893 |
26.43 |
| 2026-03-28 00:00 |
15:39:04.04 |
+53:52:49.7 |
HIP 76893 |
27.74 |
| 2026-03-28 12:00 |
15:38:58.75 |
+53:54:47.6 |
HIP 76893 |
29.15 |
| 2026-03-29 00:00 |
15:38:53.36 |
+53:56:44.7 |
HIP 76893 |
30.66 |
| 2026-03-29 12:00 |
15:38:47.86 |
+53:58:41.0 |
HIP 76311 |
31.32 |
| 2026-03-30 00:00 |
15:38:42.26 |
+54:00:36.6 |
HIP 76311 |
30.76 |
| 2026-03-30 12:00 |
15:38:36.54 |
+54:02:31.4 |
HIP 76509 |
29.54 |
| 2026-03-31 00:00 |
15:38:30.73 |
+54:04:25.5 |
HIP 76509 |
27.47 |
| 2026-03-31 12:00 |
15:38:24.81 |
+54:06:18.8 |
HIP 76509 |
25.41 |
| 2026-04-01 00:00 |
15:38:18.78 |
+54:08:11.3 |
HIP 76509 |
23.36 |
| 2026-04-01 12:00 |
15:38:12.66 |
+54:10:03.0 |
HIP 76509 |
21.32 |
| 2026-04-02 00:00 |
15:38:06.43 |
+54:11:53.9 |
HIP 76509 |
19.29 |
| 2026-04-02 12:00 |
15:38:00.10 |
+54:13:43.9 |
HIP 76509 |
17.28 |
| 2026-04-03 00:00 |
15:37:53.67 |
+54:15:33.2 |
HIP 76509 |
15.30 |
| 2026-04-03 12:00 |
15:37:47.13 |
+54:17:21.6 |
HIP 76509 |
13.35 |
| 2026-04-04 00:00 |
15:37:40.50 |
+54:19:09.2 |
HIP 76509 |
11.44 |
| 2026-04-04 12:00 |
15:37:33.78 |
+54:20:56.0 |
HIP 76509 |
9.60 |
| 2026-04-05 00:00 |
15:37:26.95 |
+54:22:41.9 |
HIP 76509 |
7.86 |
| 2026-04-05 12:00 |
15:37:20.03 |
+54:24:26.9 |
HIP 76509 |
6.32 |
| 2026-04-06 00:00 |
15:37:13.01 |
+54:26:11.1 |
HIP 76509 |
5.15 |
| 2026-04-06 12:00 |
15:37:05.90 |
+54:27:54.3 |
HIP 76509 |
4.61 |
| 2026-04-07 00:00 |
15:36:58.69 |
+54:29:36.7 |
HIP 76509 |
4.93 |
| 2026-04-07 12:00 |
15:36:51.39 |
+54:31:18.3 |
HIP 76509 |
5.95 |
| 2026-04-08 00:00 |
15:36:43.99 |
+54:32:58.9 |
HIP 76509 |
7.39 |
| 2026-04-08 12:00 |
15:36:36.51 |
+54:34:38.6 |
HIP 76376 |
6.54 |
| 2026-04-09 00:00 |
15:36:28.93 |
+54:36:17.3 |
HIP 76376 |
4.86 |
| 2026-04-09 12:00 |
15:36:21.26 |
+54:37:55.2 |
HIP 76376 |
3.50 |
| 2026-04-10 00:00 |
15:36:13.51 |
+54:39:32.1 |
HIP 76376 |
2.92 |
| 2026-04-10 12:00 |
15:36:05.67 |
+54:41:08.1 |
HIP 76376 |
3.53 |
| 2026-04-11 00:00 |
15:35:57.74 |
+54:42:43.1 |
HIP 76376 |
4.89 |
| 2026-04-11 12:00 |
15:35:49.72 |
+54:44:17.2 |
HIP 76376 |
6.54 |
| 2026-04-12 00:00 |
15:35:41.62 |
+54:45:50.3 |
HIP 76376 |
8.31 |
| 2026-04-12 12:00 |
15:35:33.44 |
+54:47:22.5 |
HIP 76376 |
10.13 |
| 2026-04-13 00:00 |
15:35:25.17 |
+54:48:53.6 |
HIP 76376 |
11.98 |
| 2026-04-13 12:00 |
15:35:16.82 |
+54:50:23.8 |
HIP 76376 |
13.84 |
| 2026-04-14 00:00 |
15:35:08.39 |
+54:51:53.0 |
HIP 76376 |
15.71 |
| 2026-04-14 12:00 |
15:34:59.88 |
+54:53:21.2 |
HIP 76376 |
17.58 |
| 2026-04-15 00:00 |
15:34:51.29 |
+54:54:48.4 |
HIP 76376 |
19.44 |
| 2026-04-15 12:00 |
15:34:42.63 |
+54:56:14.5 |
HIP 76376 |
21.31 |
| 2026-04-16 00:00 |
15:34:33.88 |
+54:57:39.7 |
HIP 76164 |
22.68 |