| Parameter |
Value |
| Designation |
C/2021 L3 (Borisov) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2022-02-13T15:37:30.763200Z |
| Orbit solution date (soln_date, UTC) |
2024-04-20T20:42:18Z |
| Obs used |
215 |
| NEO |
- |
| M1 |
9.500 |
| K1 |
6.000 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2021-06-08T21:44:52.224000Z |
| Discovery magnitude (MPC) |
20.20 R |
| Discovery observatory (MPC) |
L51 · MARGO, Nauchnyi |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2022-03-04.0000000 |
| e |
1.00141430 |
| q (au) |
8.457762 |
| a (au) |
-5980.195992 |
| i (deg) |
78.580039 |
| Ω (om, deg) |
344.969335 |
| ω (w, deg) |
91.593885 |
| M (ma, deg) |
0.000039 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.235 + 2.109\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.235 |
| n |
2.109 |
| gf |
0.990 |
| gb |
-0.789 |
| 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 |
11:18:29.94 |
+30:10:21.3 |
HIP 55362 |
22.11 |
| 2026-03-26 12:00 |
11:18:18.30 |
+30:10:02.3 |
HIP 55362 |
24.56 |
| 2026-03-27 00:00 |
11:18:06.70 |
+30:09:42.6 |
HIP 55054 |
24.45 |
| 2026-03-27 12:00 |
11:17:55.14 |
+30:09:22.0 |
HIP 55054 |
22.01 |
| 2026-03-28 00:00 |
11:17:43.63 |
+30:09:00.8 |
HIP 55054 |
19.61 |
| 2026-03-28 12:00 |
11:17:32.15 |
+30:08:38.7 |
HIP 55054 |
17.25 |
| 2026-03-29 00:00 |
11:17:20.73 |
+30:08:16.0 |
HIP 55054 |
14.96 |
| 2026-03-29 12:00 |
11:17:09.35 |
+30:07:52.4 |
HIP 55054 |
12.75 |
| 2026-03-30 00:00 |
11:16:58.01 |
+30:07:28.1 |
HIP 55054 |
10.69 |
| 2026-03-30 12:00 |
11:16:46.73 |
+30:07:03.1 |
HIP 55054 |
8.85 |
| 2026-03-31 00:00 |
11:16:35.49 |
+30:06:37.3 |
HIP 55054 |
7.42 |
| 2026-03-31 12:00 |
11:16:24.30 |
+30:06:10.8 |
HIP 55054 |
6.64 |
| 2026-04-01 00:00 |
11:16:13.16 |
+30:05:43.6 |
HIP 55054 |
6.73 |
| 2026-04-01 12:00 |
11:16:02.07 |
+30:05:15.5 |
HIP 55054 |
7.67 |
| 2026-04-02 00:00 |
11:15:51.03 |
+30:04:46.8 |
HIP 55054 |
9.18 |
| 2026-04-02 12:00 |
11:15:40.05 |
+30:04:17.3 |
HIP 55054 |
11.02 |
| 2026-04-03 00:00 |
11:15:29.11 |
+30:03:47.0 |
HIP 55054 |
13.06 |
| 2026-04-03 12:00 |
11:15:18.24 |
+30:03:16.1 |
HIP 55054 |
15.21 |
| 2026-04-04 00:00 |
11:15:07.41 |
+30:02:44.3 |
HIP 55054 |
17.42 |
| 2026-04-04 12:00 |
11:14:56.65 |
+30:02:11.9 |
HIP 55054 |
19.68 |
| 2026-04-05 00:00 |
11:14:45.94 |
+30:01:38.7 |
HIP 55054 |
21.95 |
| 2026-04-05 12:00 |
11:14:35.28 |
+30:01:04.7 |
HIP 55054 |
24.25 |
| 2026-04-06 00:00 |
11:14:24.69 |
+30:00:30.0 |
HIP 55054 |
26.55 |
| 2026-04-06 12:00 |
11:14:14.15 |
+29:59:54.6 |
HIP 54729 |
28.49 |
| 2026-04-07 00:00 |
11:14:03.68 |
+29:59:18.5 |
HIP 54729 |
26.81 |
| 2026-04-07 12:00 |
11:13:53.26 |
+29:58:41.6 |
HIP 54729 |
25.26 |
| 2026-04-08 00:00 |
11:13:42.91 |
+29:58:04.0 |
HIP 54729 |
23.85 |
| 2026-04-08 12:00 |
11:13:32.62 |
+29:57:25.7 |
HIP 54729 |
22.61 |
| 2026-04-09 00:00 |
11:13:22.39 |
+29:56:46.6 |
HIP 54729 |
21.56 |
| 2026-04-09 12:00 |
11:13:12.22 |
+29:56:06.9 |
HIP 54729 |
20.74 |
| 2026-04-10 00:00 |
11:13:02.12 |
+29:55:26.4 |
HIP 54729 |
20.17 |
| 2026-04-10 12:00 |
11:12:52.09 |
+29:54:45.1 |
HIP 54729 |
19.86 |
| 2026-04-11 00:00 |
11:12:42.12 |
+29:54:03.2 |
HIP 54729 |
19.82 |
| 2026-04-11 12:00 |
11:12:32.21 |
+29:53:20.5 |
HIP 54729 |
20.06 |
| 2026-04-12 00:00 |
11:12:22.38 |
+29:52:37.1 |
HIP 54729 |
20.55 |
| 2026-04-12 12:00 |
11:12:12.61 |
+29:51:53.0 |
HIP 54729 |
21.28 |
| 2026-04-13 00:00 |
11:12:02.91 |
+29:51:08.2 |
HIP 54778 |
21.67 |
| 2026-04-13 12:00 |
11:11:53.28 |
+29:50:22.7 |
HIP 54778 |
22.16 |
| 2026-04-14 00:00 |
11:11:43.73 |
+29:49:36.5 |
HIP 54778 |
22.83 |
| 2026-04-14 12:00 |
11:11:34.24 |
+29:48:49.5 |
HIP 54778 |
23.67 |
| 2026-04-15 00:00 |
11:11:24.82 |
+29:48:01.9 |
HIP 54778 |
24.66 |
| 2026-04-15 12:00 |
11:11:15.48 |
+29:47:13.6 |
HIP 54778 |
25.78 |
| 2026-04-16 00:00 |
11:11:06.21 |
+29:46:24.5 |
HIP 54778 |
27.02 |