LOFAR's radio push
Astronomers are using LOFAR’s low‑frequency array to scan radio wavelengths (~10 meters) for exoplanet‑style auroral bursts, monitoring over 100,000 nearby stars in parallel with a new “radio interferometric multiplexed spectroscopy” pipeline that produced ~200,000 dynamic spectra from petabytes of data — opening a whole new discovery channel for planets and technosignatures (x.com) (youtube.com).
The results are published as “The detection of circularly polarized radio bursts from stellar and exoplanetary systems” in Nature Astronomy on 27 January 2026, with Cyril Tasse (Paris Observatory) listed as lead author. (nature.com) The team applied their analysis to 1.4 years of LOFAR LoTSS survey data at ≈150 MHz drawn from a multi‑petabyte LOFAR archive, converting archival observations into time‑resolved spectra. (nature.com) Their pipeline synthesized roughly 200,000 dynamic spectra and found that about 25% of the 68 sources previously detected in LOFAR circular‑polarization maps also show significant variability on timescales of a few hours. (nature.com) The improved instantaneous sensitivity uncovered eight additional weak bursts, most varying on ~0.5–1‑hour timescales, that had been missed by traditional imaging analyses. (nature.com) Some detected bursts are consistent with magnetic star–planet interaction models rather than solely intrinsic stellar flares, and the paper highlights the nearby system GJ 687 where modeling constrains the companion GJ 687 b’s surface magnetic field to reach roughly 60 gauss if the emission is planetary in origin. (nature.com) GJ 687 b is a Neptune‑class world (≈17.2 Earth masses) orbiting at ~0.163 AU with a 38.1‑day period, making it a prime target for follow‑up to test the star–planet interaction hypothesis. (science.nasa.gov) The authors calculate that, without this multiplexed interferometric approach, achieving the same detection yield would have required nearly 180 years of targeted observations, and they note the technique’s scalability to next‑generation facilities such as the Square Kilometre Array. (astro.cornell.edu) The work is an international collaboration including the Paris Observatory team and Cornell co‑author Jake Turner, and the paper frames the method as a path to systematically probe exoplanet magnetospheres and star–planet interactions across large stellar samples. (nature.com)
