C/2021 L3 (Borisov)
| 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) |
| 2026-02-03 00:00 |
11:38:27.25 |
+29:45:49.2 |
HIP 56794 |
2.08 |
| 2026-02-03 12:00 |
11:38:17.33 |
+29:46:27.1 |
HIP 56794 |
4.32 |
| 2026-02-04 00:00 |
11:38:07.35 |
+29:47:04.7 |
HIP 56794 |
6.57 |
| 2026-02-04 12:00 |
11:37:57.29 |
+29:47:42.1 |
HIP 56794 |
8.84 |
| 2026-02-05 00:00 |
11:37:47.16 |
+29:48:19.2 |
HIP 56662 |
9.11 |
| 2026-02-05 12:00 |
11:37:36.97 |
+29:48:56.2 |
HIP 56662 |
6.96 |
| 2026-02-06 00:00 |
11:37:26.71 |
+29:49:32.8 |
HIP 56662 |
4.92 |
| 2026-02-06 12:00 |
11:37:16.39 |
+29:50:09.3 |
HIP 56662 |
3.26 |
| 2026-02-07 00:00 |
11:37:06.00 |
+29:50:45.4 |
HIP 56662 |
2.79 |
| 2026-02-07 12:00 |
11:36:55.55 |
+29:51:21.3 |
HIP 56662 |
3.98 |
| 2026-02-08 00:00 |
11:36:45.03 |
+29:51:56.9 |
HIP 56662 |
5.91 |
| 2026-02-08 12:00 |
11:36:34.46 |
+29:52:32.2 |
HIP 56662 |
8.08 |
| 2026-02-09 00:00 |
11:36:23.82 |
+29:53:07.2 |
HIP 56662 |
10.35 |
| 2026-02-09 12:00 |
11:36:13.12 |
+29:53:41.9 |
HIP 56662 |
12.66 |
| 2026-02-10 00:00 |
11:36:02.36 |
+29:54:16.3 |
HIP 56662 |
15.01 |
| 2026-02-10 12:00 |
11:35:51.54 |
+29:54:50.4 |
HIP 56662 |
17.39 |
| 2026-02-11 00:00 |
11:35:40.67 |
+29:55:24.1 |
HIP 56662 |
19.78 |
| 2026-02-11 12:00 |
11:35:29.73 |
+29:55:57.5 |
HIP 56662 |
22.18 |
| 2026-02-12 00:00 |
11:35:18.74 |
+29:56:30.6 |
HIP 56524 |
23.39 |
| 2026-02-12 12:00 |
11:35:07.70 |
+29:57:03.3 |
HIP 56524 |
23.04 |
| 2026-02-13 00:00 |
11:34:56.61 |
+29:57:35.6 |
HIP 56524 |
22.95 |
| 2026-02-13 12:00 |
11:34:45.46 |
+29:58:07.5 |
HIP 56524 |
23.14 |
| 2026-02-14 00:00 |
11:34:34.25 |
+29:58:39.1 |
HIP 56401 |
23.56 |
| 2026-02-14 12:00 |
11:34:23.00 |
+29:59:10.3 |
HIP 56401 |
23.07 |
| 2026-02-15 00:00 |
11:34:11.70 |
+29:59:41.0 |
HIP 56401 |
22.84 |
| 2026-02-15 12:00 |
11:34:00.35 |
+30:00:11.4 |
HIP 56401 |
22.87 |
| 2026-02-16 00:00 |
11:33:48.95 |
+30:00:41.3 |
HIP 56401 |
23.16 |
| 2026-02-16 12:00 |
11:33:37.51 |
+30:01:10.9 |
HIP 56401 |
23.72 |
| 2026-02-17 00:00 |
11:33:26.02 |
+30:01:40.0 |
HIP 56265 |
22.50 |
| 2026-02-17 12:00 |
11:33:14.48 |
+30:02:08.6 |
HIP 56265 |
20.19 |
| 2026-02-18 00:00 |
11:33:02.90 |
+30:02:36.8 |
HIP 56265 |
17.94 |
| 2026-02-18 12:00 |
11:32:51.28 |
+30:03:04.5 |
HIP 56265 |
15.79 |
| 2026-02-19 00:00 |
11:32:39.62 |
+30:03:31.8 |
HIP 56265 |
13.78 |
| 2026-02-19 12:00 |
11:32:27.92 |
+30:03:58.6 |
HIP 56265 |
11.97 |
| 2026-02-20 00:00 |
11:32:16.18 |
+30:04:24.9 |
HIP 56265 |
10.50 |
| 2026-02-20 12:00 |
11:32:04.40 |
+30:04:50.7 |
HIP 56265 |
9.52 |
| 2026-02-21 00:00 |
11:31:52.59 |
+30:05:16.1 |
HIP 56265 |
9.19 |
| 2026-02-21 12:00 |
11:31:40.74 |
+30:05:40.9 |
HIP 56265 |
9.59 |
| 2026-02-22 00:00 |
11:31:28.86 |
+30:06:05.2 |
HIP 56265 |
10.63 |
| 2026-02-22 12:00 |
11:31:16.94 |
+30:06:29.0 |
HIP 56265 |
12.16 |
| 2026-02-23 00:00 |
11:31:04.99 |
+30:06:52.3 |
HIP 56265 |
14.03 |
| 2026-02-23 12:00 |
11:30:53.02 |
+30:07:15.0 |
HIP 56109 |
14.08 |
| 2026-02-24 00:00 |
11:30:41.01 |
+30:07:37.3 |
HIP 56088 |
11.90 |