| Parameter |
Value |
| Designation |
C/2014 UN271 (Bernardinelli-Bernstein) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2031-01-26T01:19:48.357120Z |
| Orbit solution date (soln_date, UTC) |
2026-05-08T13:42:10Z |
| Obs used |
2201 |
| NEO |
- |
| M1 |
5.700 |
| K1 |
4.250 |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2021-11-14.0000000 |
| e |
0.99904556 |
| q (au) |
10.936302 |
| a (au) |
11458.358536 |
| i (deg) |
95.438026 |
| Ω (om, deg) |
189.914478 |
| ω (w, deg) |
326.349947 |
| M (ma, deg) |
359.997300 |
Magnitude
Scatter + Global Linear
$$
M_a = (-5.000 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-5.000 |
| n |
6.000 |
| gf |
0.800 |
| gb |
-0.746 |
| 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
Finding Chart
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
05:27:49.74 |
-68:38:06.3 |
HIP 25482 |
4.61 |
| 2026-05-12 12:00 |
05:28:16.45 |
-68:37:10.6 |
HIP 25482 |
6.99 |
| 2026-05-13 00:00 |
05:28:43.22 |
-68:36:15.6 |
HIP 25482 |
9.49 |
| 2026-05-13 12:00 |
05:29:10.08 |
-68:35:21.3 |
HIP 25482 |
12.04 |
| 2026-05-14 00:00 |
05:29:37.00 |
-68:34:27.6 |
HIP 25482 |
14.63 |
| 2026-05-14 12:00 |
05:30:04.00 |
-68:33:34.5 |
HIP 25482 |
17.23 |
| 2026-05-15 00:00 |
05:30:31.06 |
-68:32:42.1 |
HIP 25482 |
19.84 |
| 2026-05-15 12:00 |
05:30:58.20 |
-68:31:50.3 |
HIP 25482 |
22.45 |
| 2026-05-16 00:00 |
05:31:25.41 |
-68:30:59.2 |
HIP 26181 |
24.60 |
| 2026-05-16 12:00 |
05:31:52.68 |
-68:30:08.7 |
HIP 26181 |
23.33 |
| 2026-05-17 00:00 |
05:32:20.03 |
-68:29:18.9 |
HIP 26181 |
22.29 |
| 2026-05-17 12:00 |
05:32:47.44 |
-68:28:29.7 |
HIP 26181 |
21.50 |
| 2026-05-18 00:00 |
05:33:14.91 |
-68:27:41.2 |
HIP 26181 |
21.00 |
| 2026-05-18 12:00 |
05:33:42.45 |
-68:26:53.4 |
HIP 26181 |
20.81 |
| 2026-05-19 00:00 |
05:34:10.06 |
-68:26:06.2 |
HIP 26181 |
20.94 |
| 2026-05-19 12:00 |
05:34:37.72 |
-68:25:19.7 |
HIP 26181 |
21.38 |
| 2026-05-20 00:00 |
05:35:05.45 |
-68:24:33.8 |
HIP 26181 |
22.12 |
| 2026-05-20 12:00 |
05:35:33.24 |
-68:23:48.7 |
HIP 26181 |
23.13 |
| 2026-05-21 00:00 |
05:36:01.09 |
-68:23:04.2 |
HIP 26181 |
24.38 |
| 2026-05-21 12:00 |
05:36:28.99 |
-68:22:20.3 |
HIP 26181 |
25.83 |
| 2026-05-22 00:00 |
05:36:56.96 |
-68:21:37.2 |
HIP 26181 |
27.45 |
| 2026-05-22 12:00 |
05:37:24.98 |
-68:20:54.7 |
HIP 26181 |
29.22 |
| 2026-05-23 00:00 |
05:37:53.06 |
-68:20:12.9 |
HIP 26181 |
31.11 |
| 2026-05-23 12:00 |
05:38:21.20 |
-68:19:31.8 |
HIP 26995 |
32.81 |
| 2026-05-24 00:00 |
05:38:49.38 |
-68:18:51.4 |
HIP 26995 |
30.18 |
| 2026-05-24 12:00 |
05:39:17.63 |
-68:18:11.6 |
HIP 26995 |
27.56 |
| 2026-05-25 00:00 |
05:39:45.92 |
-68:17:32.5 |
HIP 26995 |
24.96 |
| 2026-05-25 12:00 |
05:40:14.27 |
-68:16:54.1 |
HIP 26995 |
22.38 |
| 2026-05-26 00:00 |
05:40:42.67 |
-68:16:16.4 |
HIP 26995 |
19.84 |
| 2026-05-26 12:00 |
05:41:11.12 |
-68:15:39.3 |
HIP 26995 |
17.35 |
| 2026-05-27 00:00 |
05:41:39.62 |
-68:15:03.0 |
HIP 26995 |
14.95 |
| 2026-05-27 12:00 |
05:42:08.17 |
-68:14:27.3 |
HIP 26995 |
12.67 |
| 2026-05-28 00:00 |
05:42:36.77 |
-68:13:52.3 |
HIP 26995 |
10.62 |
| 2026-05-28 12:00 |
05:43:05.41 |
-68:13:18.0 |
HIP 26995 |
8.93 |
| 2026-05-29 00:00 |
05:43:34.11 |
-68:12:44.4 |
HIP 26995 |
7.86 |
| 2026-05-29 12:00 |
05:44:02.84 |
-68:12:11.5 |
HIP 26995 |
7.68 |
| 2026-05-30 00:00 |
05:44:31.63 |
-68:11:39.3 |
HIP 26995 |
8.44 |
| 2026-05-30 12:00 |
05:45:00.46 |
-68:11:07.7 |
HIP 26995 |
9.94 |
| 2026-05-31 00:00 |
05:45:29.33 |
-68:10:36.9 |
HIP 26995 |
11.89 |
| 2026-05-31 12:00 |
05:45:58.25 |
-68:10:06.7 |
HIP 26995 |
14.12 |
| 2026-06-01 00:00 |
05:46:27.21 |
-68:09:37.3 |
HIP 26995 |
16.51 |
| 2026-06-01 12:00 |
05:46:56.21 |
-68:09:08.5 |
HIP 27186 |
18.58 |
| 2026-06-02 00:00 |
05:47:25.26 |
-68:08:40.4 |
HIP 27186 |
19.34 |