| 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 |
-0.502 |
| 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) |
| 2026-03-26 00:00 |
23:44:30.03 |
-03:13:36.2 |
HIP 117112 |
3.14 |
| 2026-03-26 12:00 |
23:45:20.77 |
-03:07:57.4 |
HIP 117112 |
12.32 |
| 2026-03-27 00:00 |
23:46:11.50 |
-03:02:18.5 |
HIP 117112 |
26.04 |
| 2026-03-27 12:00 |
23:47:02.22 |
-02:56:39.6 |
HIP 117375 |
17.43 |
| 2026-03-28 00:00 |
23:47:52.93 |
-02:51:00.6 |
HIP 117375 |
5.39 |
| 2026-03-28 12:00 |
23:48:43.63 |
-02:45:21.6 |
HIP 117375 |
11.78 |
| 2026-03-29 00:00 |
23:49:34.33 |
-02:39:42.6 |
HIP 117375 |
25.16 |
| 2026-03-29 12:00 |
23:50:25.02 |
-02:34:03.5 |
HIP 117614 |
11.55 |
| 2026-03-30 00:00 |
23:51:15.70 |
-02:28:24.4 |
HIP 117614 |
3.17 |
| 2026-03-30 12:00 |
23:52:06.37 |
-02:22:45.3 |
HIP 117614 |
16.46 |
| 2026-03-31 00:00 |
23:52:57.03 |
-02:17:06.2 |
HIP 117614 |
30.27 |
| 2026-03-31 12:00 |
23:53:47.68 |
-02:11:27.1 |
HIP 117881 |
19.43 |
| 2026-04-01 00:00 |
23:54:38.33 |
-02:05:48.0 |
HIP 117881 |
9.03 |
| 2026-04-01 12:00 |
23:55:28.96 |
-02:00:08.9 |
HIP 117881 |
13.01 |
| 2026-04-02 00:00 |
23:56:19.59 |
-01:54:29.8 |
HIP 117881 |
25.32 |
| 2026-04-02 12:00 |
23:57:10.21 |
-01:48:50.7 |
HIP 118156 |
16.49 |
| 2026-04-03 00:00 |
23:58:00.82 |
-01:43:11.6 |
HIP 118199 |
7.85 |
| 2026-04-03 12:00 |
23:58:51.42 |
-01:37:32.6 |
HIP 118199 |
6.28 |
| 2026-04-04 00:00 |
23:59:42.02 |
-01:31:53.6 |
HIP 118293 |
19.19 |
| 2026-04-04 12:00 |
00:00:32.60 |
-01:26:14.6 |
HIP 134 |
24.89 |
| 2026-04-05 00:00 |
00:01:23.18 |
-01:20:35.7 |
HIP 134 |
13.08 |
| 2026-04-05 12:00 |
00:02:13.75 |
-01:14:56.9 |
HIP 134 |
10.28 |
| 2026-04-06 00:00 |
00:03:04.31 |
-01:09:18.1 |
HIP 236 |
15.77 |
| 2026-04-06 12:00 |
00:03:54.86 |
-01:03:39.3 |
HIP 236 |
17.58 |
| 2026-04-07 00:00 |
00:04:45.40 |
-00:58:00.7 |
HIP 236 |
27.43 |
| 2026-04-07 12:00 |
00:05:35.93 |
-00:52:22.1 |
HIP 417 |
23.60 |
| 2026-04-08 00:00 |
00:06:26.46 |
-00:46:43.6 |
HIP 417 |
26.48 |
| 2026-04-08 12:00 |
00:07:16.97 |
-00:41:05.2 |
HIP 752 |
29.28 |
| 2026-04-09 00:00 |
00:08:07.48 |
-00:35:26.9 |
HIP 752 |
19.02 |
| 2026-04-09 12:00 |
00:08:57.98 |
-00:29:48.7 |
HIP 752 |
15.77 |
| 2026-04-10 00:00 |
00:09:48.46 |
-00:24:10.6 |
HIP 752 |
22.76 |
| 2026-04-10 12:00 |
00:10:38.94 |
-00:18:32.6 |
HIP 968 |
20.64 |
| 2026-04-11 00:00 |
00:11:29.41 |
-00:12:54.7 |
HIP 968 |
7.52 |
| 2026-04-11 12:00 |
00:12:19.87 |
-00:07:17.0 |
HIP 968 |
8.29 |
| 2026-04-12 00:00 |
00:13:10.32 |
-00:01:39.5 |
HIP 1082 |
8.46 |
| 2026-04-12 12:00 |
00:14:00.75 |
+00:03:58.0 |
HIP 1127 |
6.02 |
| 2026-04-13 00:00 |
00:14:51.18 |
+00:09:35.2 |
HIP 1127 |
16.53 |
| 2026-04-13 12:00 |
00:15:41.60 |
+00:15:12.3 |
HIP 1397 |
27.10 |
| 2026-04-14 00:00 |
00:16:32.00 |
+00:20:49.3 |
HIP 1397 |
14.27 |
| 2026-04-14 12:00 |
00:17:22.40 |
+00:26:26.0 |
HIP 1397 |
7.35 |
| 2026-04-15 00:00 |
00:18:12.78 |
+00:32:02.6 |
HIP 1437 |
10.44 |
| 2026-04-15 12:00 |
00:19:03.15 |
+00:37:38.9 |
HIP 1545 |
7.25 |
| 2026-04-16 00:00 |
00:19:53.51 |
+00:43:15.1 |
HIP 1632 |
14.88 |