| Parameter |
Value |
| Designation |
C/2013 N4 (Borisov) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2013-08-21T12:19:51.456000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:37Z |
| Obs used |
287 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
5.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2013-09-15.0000000 |
| e |
0.97480289 |
| q (au) |
1.210405 |
| a (au) |
48.037448 |
| i (deg) |
37.035278 |
| Ω (om, deg) |
322.609954 |
| ω (w, deg) |
142.280706 |
| M (ma, deg) |
0.072486 |
Magnitude
Scatter + Global Linear
$$
M_a = (13.680 + 4.775\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
13.680 |
| n |
4.775 |
| gf |
1.000 |
| gb |
-0.733 |
| 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
Residuals (Piecewise)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| Start (UTC) |
End (UTC) |
a |
b |
| 2013-07-08 |
2013-08-18 |
+21.8907 |
-2.670 |
| 2013-08-25 |
2013-12-11 |
-5.2553 |
-1.508 |
| 2013-12-11 |
2014-04-30 |
+14.2425 |
-6.622 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
18:16:29.81 |
-54:18:07.4 |
HIP 89698 |
16.23 |
| 2026-03-26 12:00 |
18:16:30.06 |
-54:18:39.6 |
HIP 89698 |
16.14 |
| 2026-03-27 00:00 |
18:16:30.25 |
-54:19:11.7 |
HIP 89698 |
16.07 |
| 2026-03-27 12:00 |
18:16:30.37 |
-54:19:43.8 |
HIP 89698 |
16.04 |
| 2026-03-28 00:00 |
18:16:30.43 |
-54:20:16.0 |
HIP 89698 |
16.03 |
| 2026-03-28 12:00 |
18:16:30.43 |
-54:20:48.1 |
HIP 89698 |
16.05 |
| 2026-03-29 00:00 |
18:16:30.36 |
-54:21:20.3 |
HIP 89698 |
16.09 |
| 2026-03-29 12:00 |
18:16:30.23 |
-54:21:52.4 |
HIP 89698 |
16.17 |
| 2026-03-30 00:00 |
18:16:30.03 |
-54:22:24.6 |
HIP 89698 |
16.27 |
| 2026-03-30 12:00 |
18:16:29.77 |
-54:22:56.8 |
HIP 89698 |
16.39 |
| 2026-03-31 00:00 |
18:16:29.45 |
-54:23:29.0 |
HIP 89698 |
16.54 |
| 2026-03-31 12:00 |
18:16:29.06 |
-54:24:01.1 |
HIP 89698 |
16.72 |
| 2026-04-01 00:00 |
18:16:28.60 |
-54:24:33.3 |
HIP 89698 |
16.92 |
| 2026-04-01 12:00 |
18:16:28.08 |
-54:25:05.4 |
HIP 89698 |
17.14 |
| 2026-04-02 00:00 |
18:16:27.50 |
-54:25:37.6 |
HIP 89698 |
17.39 |
| 2026-04-02 12:00 |
18:16:26.86 |
-54:26:09.7 |
HIP 89698 |
17.66 |
| 2026-04-03 00:00 |
18:16:26.15 |
-54:26:41.8 |
HIP 89698 |
17.95 |
| 2026-04-03 12:00 |
18:16:25.37 |
-54:27:13.8 |
HIP 89698 |
18.26 |
| 2026-04-04 00:00 |
18:16:24.53 |
-54:27:45.9 |
HIP 89698 |
18.59 |
| 2026-04-04 12:00 |
18:16:23.63 |
-54:28:17.9 |
HIP 89698 |
18.93 |
| 2026-04-05 00:00 |
18:16:22.67 |
-54:28:49.9 |
HIP 89698 |
19.30 |
| 2026-04-05 12:00 |
18:16:21.64 |
-54:29:21.9 |
HIP 89698 |
19.68 |
| 2026-04-06 00:00 |
18:16:20.54 |
-54:29:53.9 |
HIP 89698 |
20.07 |
| 2026-04-06 12:00 |
18:16:19.38 |
-54:30:25.8 |
HIP 89698 |
20.49 |
| 2026-04-07 00:00 |
18:16:18.16 |
-54:30:57.6 |
HIP 89698 |
20.91 |
| 2026-04-07 12:00 |
18:16:16.87 |
-54:31:29.5 |
HIP 89698 |
21.35 |
| 2026-04-08 00:00 |
18:16:15.52 |
-54:32:01.3 |
HIP 89698 |
21.81 |
| 2026-04-08 12:00 |
18:16:14.11 |
-54:32:33.0 |
HIP 89698 |
22.27 |
| 2026-04-09 00:00 |
18:16:12.63 |
-54:33:04.7 |
HIP 89698 |
22.75 |
| 2026-04-09 12:00 |
18:16:11.09 |
-54:33:36.4 |
HIP 89698 |
23.23 |
| 2026-04-10 00:00 |
18:16:09.49 |
-54:34:07.9 |
HIP 89698 |
23.73 |
| 2026-04-10 12:00 |
18:16:07.82 |
-54:34:39.5 |
HIP 89698 |
24.24 |
| 2026-04-11 00:00 |
18:16:06.09 |
-54:35:11.0 |
HIP 89698 |
24.76 |
| 2026-04-11 12:00 |
18:16:04.29 |
-54:35:42.4 |
HIP 89698 |
25.29 |
| 2026-04-12 00:00 |
18:16:02.43 |
-54:36:13.7 |
HIP 89698 |
25.82 |
| 2026-04-12 12:00 |
18:16:00.51 |
-54:36:45.0 |
HIP 89698 |
26.37 |
| 2026-04-13 00:00 |
18:15:58.52 |
-54:37:16.2 |
HIP 89698 |
26.92 |
| 2026-04-13 12:00 |
18:15:56.48 |
-54:37:47.4 |
HIP 89698 |
27.48 |
| 2026-04-14 00:00 |
18:15:54.36 |
-54:38:18.4 |
HIP 89698 |
28.05 |
| 2026-04-14 12:00 |
18:15:52.19 |
-54:38:49.4 |
HIP 89698 |
28.63 |
| 2026-04-15 00:00 |
18:15:49.95 |
-54:39:20.4 |
HIP 89698 |
29.21 |
| 2026-04-15 12:00 |
18:15:47.65 |
-54:39:51.2 |
HIP 89698 |
29.80 |
| 2026-04-16 00:00 |
18:15:45.29 |
-54:40:21.9 |
HIP 89281 |
29.49 |