| 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) |
| 2026-05-12 00:00 |
01:03:10.09 |
+05:27:07.9 |
HIP 4968 |
15.07 |
| 2026-05-12 12:00 |
01:03:59.52 |
+05:32:24.0 |
HIP 5074 |
14.94 |
| 2026-05-13 00:00 |
01:04:48.93 |
+05:37:39.5 |
HIP 5074 |
1.95 |
| 2026-05-13 12:00 |
01:05:38.32 |
+05:42:54.5 |
HIP 5074 |
11.90 |
| 2026-05-14 00:00 |
01:06:27.68 |
+05:48:08.9 |
HIP 5111 |
21.38 |
| 2026-05-14 12:00 |
01:07:17.02 |
+05:53:22.8 |
HIP 5346 |
21.69 |
| 2026-05-15 00:00 |
01:08:06.33 |
+05:58:36.1 |
HIP 5346 |
19.99 |
| 2026-05-15 12:00 |
01:08:55.62 |
+06:03:48.8 |
HIP 5346 |
26.14 |
| 2026-05-16 00:00 |
01:09:44.88 |
+06:09:00.9 |
HIP 5346 |
36.35 |
| 2026-05-16 12:00 |
01:10:34.11 |
+06:14:12.4 |
HIP 5511 |
30.83 |
| 2026-05-17 00:00 |
01:11:23.32 |
+06:19:23.3 |
HIP 5655 |
24.84 |
| 2026-05-17 12:00 |
01:12:12.50 |
+06:24:33.6 |
HIP 5655 |
12.87 |
| 2026-05-18 00:00 |
01:13:01.65 |
+06:29:43.3 |
HIP 5655 |
8.14 |
| 2026-05-18 12:00 |
01:13:50.77 |
+06:34:52.4 |
HIP 5655 |
17.83 |
| 2026-05-19 00:00 |
01:14:39.86 |
+06:40:00.8 |
HIP 5824 |
19.71 |
| 2026-05-19 12:00 |
01:15:28.92 |
+06:45:08.6 |
HIP 5884 |
12.28 |
| 2026-05-20 00:00 |
01:16:17.96 |
+06:50:15.7 |
HIP 5980 |
9.34 |
| 2026-05-20 12:00 |
01:17:06.96 |
+06:55:22.2 |
HIP 5980 |
7.29 |
| 2026-05-21 00:00 |
01:17:55.93 |
+07:00:28.0 |
HIP 6038 |
10.06 |
| 2026-05-21 12:00 |
01:18:44.87 |
+07:05:33.2 |
HIP 6038 |
17.81 |
| 2026-05-22 00:00 |
01:19:33.77 |
+07:10:37.7 |
HIP 6154 |
17.67 |
| 2026-05-22 12:00 |
01:20:22.65 |
+07:15:41.6 |
HIP 6205 |
18.47 |
| 2026-05-23 00:00 |
01:21:11.49 |
+07:20:44.7 |
HIP 6307 |
15.74 |
| 2026-05-23 12:00 |
01:22:00.30 |
+07:25:47.2 |
HIP 6454 |
14.00 |
| 2026-05-24 00:00 |
01:22:49.07 |
+07:30:49.0 |
HIP 6454 |
6.00 |
| 2026-05-24 12:00 |
01:23:37.82 |
+07:35:50.1 |
HIP 6454 |
14.79 |
| 2026-05-25 00:00 |
01:24:26.53 |
+07:40:50.6 |
HIP 6454 |
27.25 |
| 2026-05-25 12:00 |
01:25:15.20 |
+07:45:50.3 |
HIP 6731 |
28.96 |
| 2026-05-26 00:00 |
01:26:03.84 |
+07:50:49.3 |
HIP 6731 |
26.27 |
| 2026-05-26 12:00 |
01:26:52.45 |
+07:55:47.6 |
HIP 6868 |
22.46 |
| 2026-05-27 00:00 |
01:27:41.02 |
+08:00:45.3 |
HIP 6868 |
10.80 |
| 2026-05-27 12:00 |
01:28:29.55 |
+08:05:42.1 |
HIP 6868 |
8.19 |
| 2026-05-28 00:00 |
01:29:18.05 |
+08:10:38.3 |
HIP 6954 |
12.63 |
| 2026-05-28 12:00 |
01:30:06.52 |
+08:15:33.8 |
HIP 6954 |
11.35 |
| 2026-05-29 00:00 |
01:30:54.95 |
+08:20:28.5 |
HIP 6972 |
18.59 |
| 2026-05-29 12:00 |
01:31:43.34 |
+08:25:22.5 |
HIP 7243 |
26.77 |
| 2026-05-30 00:00 |
01:32:31.69 |
+08:30:15.7 |
HIP 7243 |
21.15 |
| 2026-05-30 12:00 |
01:33:20.01 |
+08:35:08.3 |
HIP 7243 |
22.61 |
| 2026-05-31 00:00 |
01:34:08.29 |
+08:40:00.0 |
HIP 7293 |
19.86 |
| 2026-05-31 12:00 |
01:34:56.53 |
+08:44:51.0 |
HIP 7293 |
21.06 |
| 2026-06-01 00:00 |
01:35:44.73 |
+08:49:41.3 |
HIP 7525 |
17.00 |
| 2026-06-01 12:00 |
01:36:32.89 |
+08:54:30.8 |
HIP 7525 |
5.74 |
| 2026-06-02 00:00 |
01:37:21.02 |
+08:59:19.5 |
HIP 7525 |
10.31 |