| Parameter |
Value |
| Designation |
C/2021 Q6 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-03-23T13:47:29.414400Z |
| Orbit solution date (soln_date, UTC) |
2025-09-16T12:42:41Z |
| Obs used |
388 |
| NEO |
- |
| M1 |
5.000 |
| K1 |
10.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-08-22T12:28:12.316800Z |
| Discovery magnitude (MPC) |
22.25 z |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2023-03-12.0000000 |
| e |
0.99972188 |
| q (au) |
8.709141 |
| a (au) |
31314.293105 |
| i (deg) |
161.847387 |
| Ω (om, deg) |
133.533757 |
| ω (w, deg) |
140.936211 |
| M (ma, deg) |
359.999933 |
Magnitude
Scatter + Global Linear
$$
M_a = (7.982 + 4.541\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
7.982 |
| n |
4.541 |
| gf |
0.922 |
| gb |
-0.776 |
| k |
0.812 |
| δ90 |
7.756 |
| 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 |
21:27:40.84 |
-14:20:56.4 |
HIP 105997 |
29.57 |
| 2026-03-26 12:00 |
21:27:44.61 |
-14:21:01.3 |
HIP 105997 |
29.34 |
| 2026-03-27 00:00 |
21:27:48.30 |
-14:21:06.5 |
HIP 105997 |
29.12 |
| 2026-03-27 12:00 |
21:27:51.93 |
-14:21:12.0 |
HIP 105997 |
28.93 |
| 2026-03-28 00:00 |
21:27:55.49 |
-14:21:17.9 |
HIP 105997 |
28.76 |
| 2026-03-28 12:00 |
21:27:58.99 |
-14:21:24.1 |
HIP 105997 |
28.61 |
| 2026-03-29 00:00 |
21:28:02.42 |
-14:21:30.6 |
HIP 106137 |
28.22 |
| 2026-03-29 12:00 |
21:28:05.77 |
-14:21:37.5 |
HIP 106137 |
27.47 |
| 2026-03-30 00:00 |
21:28:09.06 |
-14:21:44.7 |
HIP 106137 |
26.75 |
| 2026-03-30 12:00 |
21:28:12.28 |
-14:21:52.3 |
HIP 106137 |
26.05 |
| 2026-03-31 00:00 |
21:28:15.43 |
-14:22:00.2 |
HIP 106137 |
25.37 |
| 2026-03-31 12:00 |
21:28:18.51 |
-14:22:08.5 |
HIP 106137 |
24.72 |
| 2026-04-01 00:00 |
21:28:21.51 |
-14:22:17.1 |
HIP 106137 |
24.09 |
| 2026-04-01 12:00 |
21:28:24.45 |
-14:22:26.1 |
HIP 106137 |
23.49 |
| 2026-04-02 00:00 |
21:28:27.31 |
-14:22:35.4 |
HIP 106137 |
22.91 |
| 2026-04-02 12:00 |
21:28:30.10 |
-14:22:45.2 |
HIP 106137 |
22.36 |
| 2026-04-03 00:00 |
21:28:32.81 |
-14:22:55.3 |
HIP 106137 |
21.84 |
| 2026-04-03 12:00 |
21:28:35.46 |
-14:23:05.7 |
HIP 106137 |
21.34 |
| 2026-04-04 00:00 |
21:28:38.02 |
-14:23:16.6 |
HIP 106137 |
20.87 |
| 2026-04-04 12:00 |
21:28:40.51 |
-14:23:27.8 |
HIP 106137 |
20.43 |
| 2026-04-05 00:00 |
21:28:42.93 |
-14:23:39.4 |
HIP 106137 |
20.02 |
| 2026-04-05 12:00 |
21:28:45.27 |
-14:23:51.4 |
HIP 106137 |
19.64 |
| 2026-04-06 00:00 |
21:28:47.53 |
-14:24:03.7 |
HIP 106137 |
19.29 |
| 2026-04-06 12:00 |
21:28:49.71 |
-14:24:16.5 |
HIP 106137 |
18.97 |
| 2026-04-07 00:00 |
21:28:51.82 |
-14:24:29.7 |
HIP 106137 |
18.69 |
| 2026-04-07 12:00 |
21:28:53.85 |
-14:24:43.2 |
HIP 106137 |
18.43 |
| 2026-04-08 00:00 |
21:28:55.80 |
-14:24:57.2 |
HIP 106137 |
18.20 |
| 2026-04-08 12:00 |
21:28:57.66 |
-14:25:11.5 |
HIP 106137 |
18.01 |
| 2026-04-09 00:00 |
21:28:59.45 |
-14:25:26.3 |
HIP 106137 |
17.85 |
| 2026-04-09 12:00 |
21:29:01.16 |
-14:25:41.5 |
HIP 106137 |
17.72 |
| 2026-04-10 00:00 |
21:29:02.79 |
-14:25:57.1 |
HIP 106137 |
17.62 |
| 2026-04-10 12:00 |
21:29:04.33 |
-14:26:13.1 |
HIP 106137 |
17.55 |
| 2026-04-11 00:00 |
21:29:05.79 |
-14:26:29.5 |
HIP 106137 |
17.51 |
| 2026-04-11 12:00 |
21:29:07.17 |
-14:26:46.4 |
HIP 106137 |
17.51 |
| 2026-04-12 00:00 |
21:29:08.46 |
-14:27:03.7 |
HIP 106137 |
17.53 |
| 2026-04-12 12:00 |
21:29:09.67 |
-14:27:21.4 |
HIP 106137 |
17.58 |
| 2026-04-13 00:00 |
21:29:10.80 |
-14:27:39.6 |
HIP 106137 |
17.65 |
| 2026-04-13 12:00 |
21:29:11.84 |
-14:27:58.2 |
HIP 106137 |
17.76 |
| 2026-04-14 00:00 |
21:29:12.79 |
-14:28:17.2 |
HIP 106137 |
17.89 |
| 2026-04-14 12:00 |
21:29:13.66 |
-14:28:36.7 |
HIP 106137 |
18.04 |
| 2026-04-15 00:00 |
21:29:14.44 |
-14:28:56.6 |
HIP 106137 |
18.22 |
| 2026-04-15 12:00 |
21:29:15.13 |
-14:29:17.0 |
HIP 106137 |
18.43 |
| 2026-04-16 00:00 |
21:29:15.73 |
-14:29:37.8 |
HIP 106137 |
18.65 |