| Parameter |
Value |
| Designation |
C/2016 R3 (Borisov) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2016-10-10T23:59:06.622080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:26Z |
| Obs used |
60 |
| NEO |
- |
| M1 |
16.700 |
| K1 |
4.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2016-09-15.0000000 |
| e |
0.99548615 |
| q (au) |
0.446783 |
| a (au) |
98.980564 |
| i (deg) |
53.067840 |
| Ω (om, deg) |
78.669399 |
| ω (w, deg) |
118.135919 |
| M (ma, deg) |
359.973978 |
Magnitude
Scatter + Global Linear
$$
M_a = (17.476 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
17.476 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| 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) |
| 2026-07-29 00:00 |
02:27:54.56 |
-41:14:53.0 |
HIP 11454 |
4.28 |
| 2026-07-29 12:00 |
02:27:54.99 |
-41:15:49.6 |
HIP 11454 |
5.20 |
| 2026-07-30 00:00 |
02:27:55.37 |
-41:16:46.3 |
HIP 11454 |
6.12 |
| 2026-07-30 12:00 |
02:27:55.69 |
-41:17:43.2 |
HIP 11454 |
7.05 |
| 2026-07-31 00:00 |
02:27:55.97 |
-41:18:40.2 |
HIP 11454 |
7.99 |
| 2026-07-31 12:00 |
02:27:56.19 |
-41:19:37.4 |
HIP 11454 |
8.93 |
| 2026-08-01 00:00 |
02:27:56.37 |
-41:20:34.7 |
HIP 11454 |
9.87 |
| 2026-08-01 12:00 |
02:27:56.49 |
-41:21:32.1 |
HIP 11454 |
10.81 |
| 2026-08-02 00:00 |
02:27:56.56 |
-41:22:29.6 |
HIP 11454 |
11.76 |
| 2026-08-02 12:00 |
02:27:56.58 |
-41:23:27.3 |
HIP 11454 |
12.71 |
| 2026-08-03 00:00 |
02:27:56.55 |
-41:24:25.1 |
HIP 11393 |
13.37 |
| 2026-08-03 12:00 |
02:27:56.47 |
-41:25:23.0 |
HIP 11393 |
13.56 |
| 2026-08-04 00:00 |
02:27:56.34 |
-41:26:21.0 |
HIP 11393 |
13.81 |
| 2026-08-04 12:00 |
02:27:56.16 |
-41:27:19.1 |
HIP 11393 |
14.11 |
| 2026-08-05 00:00 |
02:27:55.92 |
-41:28:17.3 |
HIP 11393 |
14.46 |
| 2026-08-05 12:00 |
02:27:55.63 |
-41:29:15.6 |
HIP 11393 |
14.86 |
| 2026-08-06 00:00 |
02:27:55.30 |
-41:30:14.0 |
HIP 11393 |
15.31 |
| 2026-08-06 12:00 |
02:27:54.91 |
-41:31:12.5 |
HIP 11393 |
15.79 |
| 2026-08-07 00:00 |
02:27:54.46 |
-41:32:11.1 |
HIP 11393 |
16.31 |
| 2026-08-07 12:00 |
02:27:53.97 |
-41:33:09.7 |
HIP 11393 |
16.87 |
| 2026-08-08 00:00 |
02:27:53.43 |
-41:34:08.4 |
HIP 11393 |
17.46 |
| 2026-08-08 12:00 |
02:27:52.83 |
-41:35:07.2 |
HIP 11393 |
18.07 |
| 2026-08-09 00:00 |
02:27:52.18 |
-41:36:06.1 |
HIP 11393 |
18.71 |
| 2026-08-09 12:00 |
02:27:51.48 |
-41:37:05.0 |
HIP 11393 |
19.38 |
| 2026-08-10 00:00 |
02:27:50.73 |
-41:38:04.0 |
HIP 11393 |
20.07 |
| 2026-08-10 12:00 |
02:27:49.92 |
-41:39:03.0 |
HIP 11393 |
20.78 |
| 2026-08-11 00:00 |
02:27:49.07 |
-41:40:02.1 |
HIP 11393 |
21.50 |
| 2026-08-11 12:00 |
02:27:48.16 |
-41:41:01.2 |
HIP 11393 |
22.25 |
| 2026-08-12 00:00 |
02:27:47.20 |
-41:42:00.4 |
HIP 11393 |
23.00 |
| 2026-08-12 12:00 |
02:27:46.18 |
-41:42:59.6 |
HIP 11609 |
23.64 |
| 2026-08-13 00:00 |
02:27:45.12 |
-41:43:58.8 |
HIP 11609 |
23.49 |
| 2026-08-13 12:00 |
02:27:44.00 |
-41:44:58.0 |
HIP 11609 |
23.39 |
| 2026-08-14 00:00 |
02:27:42.83 |
-41:45:57.2 |
HIP 11609 |
23.34 |
| 2026-08-14 12:00 |
02:27:41.61 |
-41:46:56.5 |
HIP 11609 |
23.35 |
| 2026-08-15 00:00 |
02:27:40.34 |
-41:47:55.8 |
HIP 11609 |
23.41 |
| 2026-08-15 12:00 |
02:27:39.01 |
-41:48:55.0 |
HIP 11575 |
23.27 |
| 2026-08-16 00:00 |
02:27:37.64 |
-41:49:54.3 |
HIP 11575 |
22.82 |
| 2026-08-16 12:00 |
02:27:36.21 |
-41:50:53.5 |
HIP 11575 |
22.41 |
| 2026-08-17 00:00 |
02:27:34.73 |
-41:51:52.8 |
HIP 11575 |
22.04 |
| 2026-08-17 12:00 |
02:27:33.20 |
-41:52:52.0 |
HIP 11575 |
21.73 |
| 2026-08-18 00:00 |
02:27:31.62 |
-41:53:51.2 |
HIP 11575 |
21.47 |
| 2026-08-18 12:00 |
02:27:29.98 |
-41:54:50.4 |
HIP 11575 |
21.27 |
| 2026-08-19 00:00 |
02:27:28.30 |
-41:55:49.5 |
HIP 11575 |
21.12 |