| Parameter |
Value |
| Designation |
C/2023 Q1 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2024-12-01T03:06:18.527040Z |
| Orbit solution date (soln_date, UTC) |
2025-09-30T13:39:24Z |
| Obs used |
1450 |
| NEO |
- |
| M1 |
11.200 |
| K1 |
9.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2023-08-20T13:18:30.182400Z |
| Discovery magnitude (MPC) |
22.04 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2024-12-04.0000000 |
| e |
1.00529337 |
| q (au) |
2.575719 |
| a (au) |
-486.593364 |
| i (deg) |
36.643014 |
| Ω (om, deg) |
7.131719 |
| ω (w, deg) |
84.409436 |
| M (ma, deg) |
0.000264 |
Magnitude
Scatter + Global Linear
$$
M_a = (10.831 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
10.831 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.794 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2023-07-25 |
2023-11-14 |
+13.9933 |
-9.563 |
| 2023-11-14 |
2024-07-30 |
+1.1915 |
-1.285 |
| 2024-07-30 |
2024-12-01 |
-28.2334 |
+12.220 |
| 2024-12-01 |
2025-05-15 |
+2.7850 |
-1.351 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
12:19:28.21 |
+00:38:57.6 |
HIP 60062 |
31.74 |
| 2026-03-26 12:00 |
12:19:09.04 |
+00:39:08.6 |
HIP 60062 |
30.88 |
| 2026-03-27 00:00 |
12:18:49.90 |
+00:39:19.4 |
HIP 60062 |
30.76 |
| 2026-03-27 12:00 |
12:18:30.81 |
+00:39:30.0 |
HIP 59890 |
29.52 |
| 2026-03-28 00:00 |
12:18:11.75 |
+00:39:40.4 |
HIP 59890 |
26.08 |
| 2026-03-28 12:00 |
12:17:52.74 |
+00:39:50.5 |
HIP 59890 |
23.13 |
| 2026-03-29 00:00 |
12:17:33.77 |
+00:40:00.3 |
HIP 59890 |
20.85 |
| 2026-03-29 12:00 |
12:17:14.85 |
+00:40:09.9 |
HIP 59890 |
19.48 |
| 2026-03-30 00:00 |
12:16:55.99 |
+00:40:19.3 |
HIP 59890 |
19.20 |
| 2026-03-30 12:00 |
12:16:37.18 |
+00:40:28.3 |
HIP 59890 |
20.06 |
| 2026-03-31 00:00 |
12:16:18.42 |
+00:40:37.1 |
HIP 59890 |
21.90 |
| 2026-03-31 12:00 |
12:15:59.72 |
+00:40:45.6 |
HIP 59890 |
24.50 |
| 2026-04-01 00:00 |
12:15:41.09 |
+00:40:53.7 |
HIP 59890 |
27.64 |
| 2026-04-01 12:00 |
12:15:22.52 |
+00:41:01.6 |
HIP 59890 |
31.15 |
| 2026-04-02 00:00 |
12:15:04.02 |
+00:41:09.1 |
HIP 59890 |
34.90 |
| 2026-04-02 12:00 |
12:14:45.58 |
+00:41:16.2 |
HIP 59890 |
38.83 |
| 2026-04-03 00:00 |
12:14:27.22 |
+00:41:23.0 |
HIP 59890 |
42.87 |
| 2026-04-03 12:00 |
12:14:08.93 |
+00:41:29.5 |
HIP 59500 |
41.69 |
| 2026-04-04 00:00 |
12:13:50.71 |
+00:41:35.6 |
HIP 59500 |
38.44 |
| 2026-04-04 12:00 |
12:13:32.58 |
+00:41:41.3 |
HIP 59500 |
35.50 |
| 2026-04-05 00:00 |
12:13:14.52 |
+00:41:46.6 |
HIP 59500 |
32.93 |
| 2026-04-05 12:00 |
12:12:56.55 |
+00:41:51.5 |
HIP 59500 |
30.83 |
| 2026-04-06 00:00 |
12:12:38.66 |
+00:41:56.1 |
HIP 59500 |
29.28 |
| 2026-04-06 12:00 |
12:12:20.86 |
+00:42:00.2 |
HIP 59376 |
27.88 |
| 2026-04-07 00:00 |
12:12:03.15 |
+00:42:03.8 |
HIP 59376 |
24.72 |
| 2026-04-07 12:00 |
12:11:45.54 |
+00:42:07.1 |
HIP 59376 |
22.00 |
| 2026-04-08 00:00 |
12:11:28.01 |
+00:42:09.9 |
HIP 59376 |
19.90 |
| 2026-04-08 12:00 |
12:11:10.59 |
+00:42:12.2 |
HIP 59376 |
18.61 |
| 2026-04-09 00:00 |
12:10:53.26 |
+00:42:14.1 |
HIP 59376 |
18.28 |
| 2026-04-09 12:00 |
12:10:36.03 |
+00:42:15.5 |
HIP 59376 |
18.95 |
| 2026-04-10 00:00 |
12:10:18.90 |
+00:42:16.5 |
HIP 59376 |
20.50 |
| 2026-04-10 12:00 |
12:10:01.88 |
+00:42:16.9 |
HIP 59376 |
22.74 |
| 2026-04-11 00:00 |
12:09:44.97 |
+00:42:16.9 |
HIP 59376 |
25.47 |
| 2026-04-11 12:00 |
12:09:28.16 |
+00:42:16.3 |
HIP 59164 |
22.45 |
| 2026-04-12 00:00 |
12:09:11.47 |
+00:42:15.3 |
HIP 59164 |
18.40 |
| 2026-04-12 12:00 |
12:08:54.89 |
+00:42:13.7 |
HIP 59164 |
14.45 |
| 2026-04-13 00:00 |
12:08:38.42 |
+00:42:11.6 |
HIP 59164 |
10.66 |
| 2026-04-13 12:00 |
12:08:22.07 |
+00:42:08.9 |
HIP 59164 |
7.25 |
| 2026-04-14 00:00 |
12:08:05.84 |
+00:42:05.7 |
HIP 59164 |
4.99 |
| 2026-04-14 12:00 |
12:07:49.73 |
+00:42:02.0 |
HIP 59142 |
3.02 |
| 2026-04-15 00:00 |
12:07:33.74 |
+00:41:57.6 |
HIP 59142 |
1.15 |
| 2026-04-15 12:00 |
12:07:17.88 |
+00:41:52.8 |
HIP 59142 |
5.02 |
| 2026-04-16 00:00 |
12:07:02.14 |
+00:41:47.3 |
HIP 59142 |
8.94 |