C/2014 UN271 (Bernardinelli-Bernstein)
Metadata
| Parameter | Value |
|---|---|
| Designation | C/2014 UN271 (Bernardinelli-Bernstein) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2031-01-27T20:16:44.492160Z |
| Orbit solution date (soln_date, UTC) | 2026-01-13T08:12:15Z |
| Obs used | 1746 |
| NEO | - |
| M1 | 5.500 |
| K1 | 4.500 |
| PC | - |
Osculating Elements
| Parameter | Value |
|---|---|
| Epoch (epoch_cal, TDB) | 2021-03-26.0000000 |
| e | 0.99820385 |
| q (au) | 10.932360 |
| a (au) | 6086.546509 |
| i (deg) | 95.451889 |
| Ω (om, deg) | 189.940067 |
| ω (w, deg) | 326.397004 |
| M (ma, deg) | 359.992538 |
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 | -0.743 |
| 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 |
|---|---|---|---|
| 2021-07-07 | 2024-05-22 | -4.0267 | +5.086 |
| 2024-05-22 | 2026-02-06 | +11.8792 | -13.895 |
log10 r = log10(heliocentric distance / AU), Δ = geocentric distance (AU)
Finding Chart
Ephemeris
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 04:44:29.30 | -73:38:13.5 | HIP 22219 | 19.34 |
| 2026-02-03 12:00 | 04:44:23.22 | -73:36:43.8 | HIP 22219 | 20.86 |
| 2026-02-04 00:00 | 04:44:17.37 | -73:35:13.6 | HIP 22219 | 22.38 |
| 2026-02-04 12:00 | 04:44:11.76 | -73:33:42.9 | HIP 22219 | 23.91 |
| 2026-02-05 00:00 | 04:44:06.39 | -73:32:11.6 | HIP 22219 | 25.45 |
| 2026-02-05 12:00 | 04:44:01.26 | -73:30:39.8 | HIP 22219 | 26.99 |
| 2026-02-06 00:00 | 04:43:56.37 | -73:29:07.6 | HIP 22219 | 28.53 |
| 2026-02-06 12:00 | 04:43:51.72 | -73:27:34.8 | HIP 22219 | 30.08 |
| 2026-02-07 00:00 | 04:43:47.31 | -73:26:01.6 | HIP 22219 | 31.63 |
| 2026-02-07 12:00 | 04:43:43.14 | -73:24:27.9 | HIP 22219 | 33.19 |
| 2026-02-08 00:00 | 04:43:39.21 | -73:22:53.7 | HIP 22219 | 34.75 |
| 2026-02-08 12:00 | 04:43:35.52 | -73:21:19.1 | HIP 22219 | 36.31 |
| 2026-02-09 00:00 | 04:43:32.07 | -73:19:44.0 | HIP 22219 | 37.88 |
| 2026-02-09 12:00 | 04:43:28.86 | -73:18:08.5 | HIP 22219 | 39.46 |
| 2026-02-10 00:00 | 04:43:25.90 | -73:16:32.6 | HIP 21300 | 39.88 |
| 2026-02-10 12:00 | 04:43:23.17 | -73:14:56.2 | HIP 21300 | 39.58 |
| 2026-02-11 00:00 | 04:43:20.68 | -73:13:19.5 | HIP 21300 | 39.37 |
| 2026-02-11 12:00 | 04:43:18.44 | -73:11:42.3 | HIP 21300 | 39.24 |
| 2026-02-12 00:00 | 04:43:16.43 | -73:10:04.8 | HIP 21300 | 39.19 |
| 2026-02-12 12:00 | 04:43:14.67 | -73:08:26.8 | HIP 21300 | 39.23 |
| 2026-02-13 00:00 | 04:43:13.14 | -73:06:48.5 | HIP 22102 | 37.89 |
| 2026-02-13 12:00 | 04:43:11.85 | -73:05:09.9 | HIP 22102 | 36.33 |
| 2026-02-14 00:00 | 04:43:10.80 | -73:03:30.9 | HIP 22102 | 34.77 |
| 2026-02-14 12:00 | 04:43:09.99 | -73:01:51.5 | HIP 22102 | 33.20 |
| 2026-02-15 00:00 | 04:43:09.42 | -73:00:11.8 | HIP 22102 | 31.63 |
| 2026-02-15 12:00 | 04:43:09.09 | -72:58:31.8 | HIP 22102 | 30.06 |
| 2026-02-16 00:00 | 04:43:08.99 | -72:56:51.4 | HIP 22102 | 28.50 |
| 2026-02-16 12:00 | 04:43:09.14 | -72:55:10.8 | HIP 22102 | 26.93 |
| 2026-02-17 00:00 | 04:43:09.52 | -72:53:29.8 | HIP 22102 | 25.36 |
| 2026-02-17 12:00 | 04:43:10.13 | -72:51:48.6 | HIP 22102 | 23.80 |
| 2026-02-18 00:00 | 04:43:10.98 | -72:50:07.1 | HIP 22102 | 22.25 |
| 2026-02-18 12:00 | 04:43:12.07 | -72:48:25.3 | HIP 22102 | 20.70 |
| 2026-02-19 00:00 | 04:43:13.39 | -72:46:43.3 | HIP 22102 | 19.17 |
| 2026-02-19 12:00 | 04:43:14.95 | -72:45:01.0 | HIP 22102 | 17.66 |
| 2026-02-20 00:00 | 04:43:16.74 | -72:43:18.5 | HIP 22102 | 16.17 |
| 2026-02-20 12:00 | 04:43:18.77 | -72:41:35.7 | HIP 22102 | 14.72 |
| 2026-02-21 00:00 | 04:43:21.02 | -72:39:52.7 | HIP 22102 | 13.32 |
| 2026-02-21 12:00 | 04:43:23.51 | -72:38:09.5 | HIP 22102 | 11.98 |
| 2026-02-22 00:00 | 04:43:26.23 | -72:36:26.1 | HIP 22102 | 10.75 |
| 2026-02-22 12:00 | 04:43:29.18 | -72:34:42.6 | HIP 22102 | 9.65 |
| 2026-02-23 00:00 | 04:43:32.35 | -72:32:58.8 | HIP 22102 | 8.74 |
| 2026-02-23 12:00 | 04:43:35.76 | -72:31:14.8 | HIP 22102 | 8.09 |
| 2026-02-24 00:00 | 04:43:39.39 | -72:29:30.7 | HIP 22102 | 7.77 |