| Parameter |
Value |
| Designation |
P/1996 R2 (Lagerkvist) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
1997-01-19T04:33:27.567360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:50Z |
| Obs used |
137 |
| NEO |
- |
| M1 |
6.900 |
| K1 |
20.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1996-10-08.0000000 |
| e |
0.30999078 |
| q (au) |
2.609642 |
| a (au) |
3.782040 |
| i (deg) |
2.605342 |
| Ω (om, deg) |
40.240561 |
| ω (w, deg) |
334.042486 |
| M (ma, deg) |
346.172231 |
Magnitude
Scatter + Global Linear
$$
M_a = (8.462 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
8.462 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.998 |
| 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
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
03:45:40.73 |
+19:48:17.8 |
HIP 17503 |
11.33 |
| 2026-09-20 12:00 |
03:45:49.09 |
+19:49:12.4 |
HIP 17503 |
13.21 |
| 2026-09-21 00:00 |
03:45:57.07 |
+19:50:05.9 |
HIP 17503 |
15.07 |
| 2026-09-21 12:00 |
03:46:04.65 |
+19:50:58.2 |
HIP 17503 |
16.89 |
| 2026-09-22 00:00 |
03:46:11.85 |
+19:51:49.5 |
HIP 17503 |
18.65 |
| 2026-09-22 12:00 |
03:46:18.65 |
+19:52:39.6 |
HIP 17503 |
20.34 |
| 2026-09-23 00:00 |
03:46:25.06 |
+19:53:28.6 |
HIP 17503 |
21.95 |
| 2026-09-23 12:00 |
03:46:31.08 |
+19:54:16.4 |
HIP 17503 |
23.48 |
| 2026-09-24 00:00 |
03:46:36.70 |
+19:55:03.2 |
HIP 17503 |
24.93 |
| 2026-09-24 12:00 |
03:46:41.93 |
+19:55:48.8 |
HIP 17503 |
26.30 |
| 2026-09-25 00:00 |
03:46:46.76 |
+19:56:33.2 |
HIP 17503 |
27.57 |
| 2026-09-25 12:00 |
03:46:51.19 |
+19:57:16.6 |
HIP 17503 |
28.76 |
| 2026-09-26 00:00 |
03:46:55.22 |
+19:57:58.8 |
HIP 17503 |
29.86 |
| 2026-09-26 12:00 |
03:46:58.85 |
+19:58:39.9 |
HIP 17503 |
30.87 |
| 2026-09-27 00:00 |
03:47:02.09 |
+19:59:19.8 |
HIP 17503 |
31.79 |
| 2026-09-27 12:00 |
03:47:04.92 |
+19:59:58.6 |
HIP 17503 |
32.62 |
| 2026-09-28 00:00 |
03:47:07.35 |
+20:00:36.3 |
HIP 17503 |
33.36 |
| 2026-09-28 12:00 |
03:47:09.37 |
+20:01:12.8 |
HIP 17503 |
34.01 |
| 2026-09-29 00:00 |
03:47:10.99 |
+20:01:48.2 |
HIP 17503 |
34.57 |
| 2026-09-29 12:00 |
03:47:12.21 |
+20:02:22.4 |
HIP 17503 |
35.04 |
| 2026-09-30 00:00 |
03:47:13.02 |
+20:02:55.4 |
HIP 17503 |
35.41 |
| 2026-09-30 12:00 |
03:47:13.42 |
+20:03:27.3 |
HIP 17503 |
35.70 |
| 2026-10-01 00:00 |
03:47:13.42 |
+20:03:58.1 |
HIP 17503 |
35.90 |
| 2026-10-01 12:00 |
03:47:13.01 |
+20:04:27.7 |
HIP 17503 |
36.00 |
| 2026-10-02 00:00 |
03:47:12.19 |
+20:04:56.1 |
HIP 17503 |
36.02 |
| 2026-10-02 12:00 |
03:47:10.96 |
+20:05:23.4 |
HIP 17503 |
35.95 |
| 2026-10-03 00:00 |
03:47:09.32 |
+20:05:49.5 |
HIP 17503 |
35.80 |
| 2026-10-03 12:00 |
03:47:07.28 |
+20:06:14.4 |
HIP 17503 |
35.56 |
| 2026-10-04 00:00 |
03:47:04.82 |
+20:06:38.1 |
HIP 17503 |
35.23 |
| 2026-10-04 12:00 |
03:47:01.96 |
+20:07:00.7 |
HIP 17503 |
34.83 |
| 2026-10-05 00:00 |
03:46:58.68 |
+20:07:22.1 |
HIP 17503 |
34.34 |
| 2026-10-05 12:00 |
03:46:55.00 |
+20:07:42.3 |
HIP 17503 |
33.78 |
| 2026-10-06 00:00 |
03:46:50.91 |
+20:08:01.4 |
HIP 17503 |
33.14 |
| 2026-10-06 12:00 |
03:46:46.41 |
+20:08:19.2 |
HIP 17503 |
32.43 |
| 2026-10-07 00:00 |
03:46:41.51 |
+20:08:35.9 |
HIP 17503 |
31.65 |
| 2026-10-07 12:00 |
03:46:36.20 |
+20:08:51.4 |
HIP 17503 |
30.82 |
| 2026-10-08 00:00 |
03:46:30.49 |
+20:09:05.7 |
HIP 17503 |
29.92 |
| 2026-10-08 12:00 |
03:46:24.37 |
+20:09:18.9 |
HIP 17503 |
28.98 |
| 2026-10-09 00:00 |
03:46:17.85 |
+20:09:30.8 |
HIP 17503 |
28.01 |
| 2026-10-09 12:00 |
03:46:10.93 |
+20:09:41.6 |
HIP 17503 |
27.01 |
| 2026-10-10 00:00 |
03:46:03.62 |
+20:09:51.2 |
HIP 17503 |
26.00 |
| 2026-10-10 12:00 |
03:45:55.90 |
+20:09:59.6 |
HIP 17503 |
24.99 |
| 2026-10-11 00:00 |
03:45:47.79 |
+20:10:06.9 |
HIP 17503 |
24.02 |