227P/Catalina-LINEAR
| Parameter |
Value |
| Designation |
227P/Catalina-LINEAR |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2024-03-15T05:19:57.423360Z |
| Orbit solution date (soln_date, UTC) |
2025-01-10T09:12:26Z |
| Obs used |
1235 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
18.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-03-27.0000000 |
| e |
0.51043355 |
| q (au) |
1.742453 |
| a (au) |
3.559175 |
| i (deg) |
6.512508 |
| Ω (om, deg) |
48.592710 |
| ω (w, deg) |
90.858601 |
| M (ma, deg) |
200.853061 |
Magnitude
Scatter + Global Linear
$$
M_a = (11.892 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
11.892 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2023-10-09 |
2023-12-06 |
+3.9053 |
+0.883 |
| 2023-12-06 |
2024-03-15 |
+40.6801 |
-8.847 |
| 2024-03-15 |
2024-07-23 |
-1.7736 |
-0.021 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-02-03 00:00 |
20:02:08.83 |
-26:41:13.3 |
HIP 98521 |
32.35 |
| 2026-02-03 12:00 |
20:02:39.47 |
-26:40:01.5 |
HIP 98839 |
29.96 |
| 2026-02-04 00:00 |
20:03:10.05 |
-26:38:49.7 |
HIP 98839 |
24.40 |
| 2026-02-04 12:00 |
20:03:40.58 |
-26:37:37.9 |
HIP 98839 |
19.74 |
| 2026-02-05 00:00 |
20:04:11.06 |
-26:36:26.1 |
HIP 98839 |
16.75 |
| 2026-02-05 12:00 |
20:04:41.47 |
-26:35:14.4 |
HIP 98926 |
15.17 |
| 2026-02-06 00:00 |
20:05:11.83 |
-26:34:02.6 |
HIP 98926 |
14.75 |
| 2026-02-06 12:00 |
20:05:42.13 |
-26:32:50.9 |
HIP 99070 |
15.95 |
| 2026-02-07 00:00 |
20:06:12.36 |
-26:31:39.3 |
HIP 99070 |
9.49 |
| 2026-02-07 12:00 |
20:06:42.54 |
-26:30:27.6 |
HIP 99070 |
4.47 |
| 2026-02-08 00:00 |
20:07:12.66 |
-26:29:16.0 |
HIP 99070 |
6.62 |
| 2026-02-08 12:00 |
20:07:42.71 |
-26:28:04.5 |
HIP 99070 |
12.70 |
| 2026-02-09 00:00 |
20:08:12.71 |
-26:26:53.0 |
HIP 99273 |
17.87 |
| 2026-02-09 12:00 |
20:08:42.64 |
-26:25:41.6 |
HIP 99273 |
13.26 |
| 2026-02-10 00:00 |
20:09:12.50 |
-26:24:30.2 |
HIP 99273 |
11.19 |
| 2026-02-10 12:00 |
20:09:42.31 |
-26:23:18.9 |
HIP 99273 |
12.92 |
| 2026-02-11 00:00 |
20:10:12.04 |
-26:22:07.7 |
HIP 99273 |
17.32 |
| 2026-02-11 12:00 |
20:10:41.71 |
-26:20:56.5 |
HIP 99536 |
18.13 |
| 2026-02-12 00:00 |
20:11:11.32 |
-26:19:45.4 |
HIP 99536 |
11.65 |
| 2026-02-12 12:00 |
20:11:40.85 |
-26:18:34.5 |
HIP 99536 |
5.81 |
| 2026-02-13 00:00 |
20:12:10.32 |
-26:17:23.6 |
HIP 99536 |
4.70 |
| 2026-02-13 12:00 |
20:12:39.72 |
-26:16:12.8 |
HIP 99613 |
6.00 |
| 2026-02-14 00:00 |
20:13:09.05 |
-26:15:02.1 |
HIP 99613 |
4.63 |
| 2026-02-14 12:00 |
20:13:38.30 |
-26:13:51.5 |
HIP 99613 |
9.80 |
| 2026-02-15 00:00 |
20:14:07.49 |
-26:12:41.0 |
HIP 99613 |
16.09 |
| 2026-02-15 12:00 |
20:14:36.60 |
-26:11:30.6 |
HIP 99613 |
22.57 |
| 2026-02-16 00:00 |
20:15:05.64 |
-26:10:20.4 |
HIP 99613 |
29.11 |
| 2026-02-16 12:00 |
20:15:34.61 |
-26:09:10.3 |
HIP 99937 |
28.63 |
| 2026-02-17 00:00 |
20:16:03.50 |
-26:08:00.3 |
HIP 100038 |
24.72 |
| 2026-02-17 12:00 |
20:16:32.32 |
-26:06:50.4 |
HIP 100038 |
18.38 |
| 2026-02-18 00:00 |
20:17:01.06 |
-26:05:40.8 |
HIP 100038 |
12.31 |
| 2026-02-18 12:00 |
20:17:29.72 |
-26:04:31.2 |
HIP 100038 |
7.17 |
| 2026-02-19 00:00 |
20:17:58.30 |
-26:03:21.8 |
HIP 100038 |
6.06 |
| 2026-02-19 12:00 |
20:18:26.81 |
-26:02:12.6 |
HIP 100038 |
10.34 |
| 2026-02-20 00:00 |
20:18:55.23 |
-26:01:03.5 |
HIP 100182 |
9.97 |
| 2026-02-20 12:00 |
20:19:23.58 |
-25:59:54.6 |
HIP 100182 |
10.36 |
| 2026-02-21 00:00 |
20:19:51.84 |
-25:58:45.9 |
HIP 100182 |
14.09 |
| 2026-02-21 12:00 |
20:20:20.02 |
-25:57:37.4 |
HIP 100311 |
12.23 |
| 2026-02-22 00:00 |
20:20:48.12 |
-25:56:29.0 |
HIP 100311 |
12.56 |
| 2026-02-22 12:00 |
20:21:16.13 |
-25:55:20.9 |
HIP 100311 |
15.75 |
| 2026-02-23 00:00 |
20:21:44.06 |
-25:54:12.9 |
HIP 100474 |
18.68 |
| 2026-02-23 12:00 |
20:22:11.91 |
-25:53:05.2 |
HIP 100474 |
17.07 |
| 2026-02-24 00:00 |
20:22:39.67 |
-25:51:57.6 |
HIP 100474 |
17.73 |