| Parameter |
Value |
| Designation |
C/2014 R1 (Borisov) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2014-11-19T05:45:38.039040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:59Z |
| Obs used |
523 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
13.250 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2015-01-09.0000000 |
| e |
0.99249938 |
| q (au) |
1.345431 |
| a (au) |
179.376061 |
| i (deg) |
9.932908 |
| Ω (om, deg) |
104.051786 |
| ω (w, deg) |
55.649107 |
| M (ma, deg) |
0.020825 |
Magnitude
Scatter + Global Linear
$$
M_a = (9.468 + 5.229\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
9.468 |
| n |
5.229 |
| gf |
1.000 |
| gb |
-0.935 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2014-09-05 |
2014-11-18 |
+15.2936 |
-3.191 |
| 2014-11-19 |
2015-08-06 |
+3.9121 |
-1.721 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
21:16:24.18 |
-21:23:09.1 |
HIP 104993 |
8.04 |
| 2026-07-29 12:00 |
21:16:19.98 |
-21:23:29.2 |
HIP 104993 |
7.01 |
| 2026-07-30 00:00 |
21:16:15.77 |
-21:23:49.4 |
HIP 104993 |
5.98 |
| 2026-07-30 12:00 |
21:16:11.55 |
-21:24:09.5 |
HIP 104993 |
4.95 |
| 2026-07-31 00:00 |
21:16:07.32 |
-21:24:29.5 |
HIP 104993 |
3.93 |
| 2026-07-31 12:00 |
21:16:03.09 |
-21:24:49.5 |
HIP 104993 |
2.91 |
| 2026-08-01 00:00 |
21:15:58.86 |
-21:25:09.5 |
HIP 104993 |
1.92 |
| 2026-08-01 12:00 |
21:15:54.61 |
-21:25:29.4 |
HIP 104993 |
1.02 |
| 2026-08-02 00:00 |
21:15:50.37 |
-21:25:49.4 |
HIP 104993 |
0.76 |
| 2026-08-02 12:00 |
21:15:46.12 |
-21:26:09.2 |
HIP 104993 |
1.51 |
| 2026-08-03 00:00 |
21:15:41.86 |
-21:26:29.0 |
HIP 104993 |
2.49 |
| 2026-08-03 12:00 |
21:15:37.60 |
-21:26:48.8 |
HIP 104993 |
3.50 |
| 2026-08-04 00:00 |
21:15:33.34 |
-21:27:08.5 |
HIP 104993 |
4.53 |
| 2026-08-04 12:00 |
21:15:29.07 |
-21:27:28.2 |
HIP 104993 |
5.57 |
| 2026-08-05 00:00 |
21:15:24.80 |
-21:27:47.8 |
HIP 104993 |
6.61 |
| 2026-08-05 12:00 |
21:15:20.52 |
-21:28:07.4 |
HIP 104993 |
7.65 |
| 2026-08-06 00:00 |
21:15:16.25 |
-21:28:27.0 |
HIP 104993 |
8.69 |
| 2026-08-06 12:00 |
21:15:11.97 |
-21:28:46.4 |
HIP 104993 |
9.74 |
| 2026-08-07 00:00 |
21:15:07.69 |
-21:29:05.9 |
HIP 104993 |
10.78 |
| 2026-08-07 12:00 |
21:15:03.41 |
-21:29:25.2 |
HIP 104993 |
11.83 |
| 2026-08-08 00:00 |
21:14:59.13 |
-21:29:44.5 |
HIP 104926 |
12.58 |
| 2026-08-08 12:00 |
21:14:54.85 |
-21:30:03.8 |
HIP 104926 |
13.21 |
| 2026-08-09 00:00 |
21:14:50.57 |
-21:30:22.9 |
HIP 104926 |
13.88 |
| 2026-08-09 12:00 |
21:14:46.28 |
-21:30:42.1 |
HIP 104926 |
14.60 |
| 2026-08-10 00:00 |
21:14:42.00 |
-21:31:01.1 |
HIP 104926 |
15.35 |
| 2026-08-10 12:00 |
21:14:37.72 |
-21:31:20.1 |
HIP 104926 |
16.13 |
| 2026-08-11 00:00 |
21:14:33.44 |
-21:31:39.0 |
HIP 104926 |
16.95 |
| 2026-08-11 12:00 |
21:14:29.17 |
-21:31:57.9 |
HIP 104926 |
17.78 |
| 2026-08-12 00:00 |
21:14:24.89 |
-21:32:16.6 |
HIP 104926 |
18.64 |
| 2026-08-12 12:00 |
21:14:20.62 |
-21:32:35.3 |
HIP 104908 |
19.09 |
| 2026-08-13 00:00 |
21:14:16.35 |
-21:32:54.0 |
HIP 104908 |
19.36 |
| 2026-08-13 12:00 |
21:14:12.08 |
-21:33:12.5 |
HIP 104908 |
19.69 |
| 2026-08-14 00:00 |
21:14:07.82 |
-21:33:31.0 |
HIP 104908 |
20.06 |
| 2026-08-14 12:00 |
21:14:03.56 |
-21:33:49.4 |
HIP 104908 |
20.48 |
| 2026-08-15 00:00 |
21:13:59.31 |
-21:34:07.7 |
HIP 104908 |
20.95 |
| 2026-08-15 12:00 |
21:13:55.06 |
-21:34:25.9 |
HIP 104908 |
21.45 |
| 2026-08-16 00:00 |
21:13:50.81 |
-21:34:44.0 |
HIP 104908 |
21.99 |
| 2026-08-16 12:00 |
21:13:46.57 |
-21:35:02.1 |
HIP 104908 |
22.57 |
| 2026-08-17 00:00 |
21:13:42.34 |
-21:35:20.0 |
HIP 104908 |
23.17 |
| 2026-08-17 12:00 |
21:13:38.11 |
-21:35:37.9 |
HIP 104908 |
23.81 |
| 2026-08-18 00:00 |
21:13:33.89 |
-21:35:55.7 |
HIP 104908 |
24.47 |
| 2026-08-18 12:00 |
21:13:29.68 |
-21:36:13.4 |
HIP 104908 |
25.15 |
| 2026-08-19 00:00 |
21:13:25.48 |
-21:36:31.0 |
HIP 104908 |
25.86 |