Analysis: Science & Technology — 10 October 2026
NC State laser plasma filament transmits 30 MHz radio waves
Researchers at North Carolina State University have shown that a laser-generated plasma filament in air can act as a radio antenna, transmitting at 30 megahertz in the VHF band. The work, published in the IEEE Journal of Microwaves, uses a contactless capacitive feed: a metal ring couples a radio-frequency signal into a thin ionized channel created by the laser. The result stands out because antenna length, which sets operating frequency, can in principle be changed by adjusting the laser rather than moving metal. Reception and a broad frequency sweep have not been demonstrated.
Conventional antennas are sized to the wavelengths they handle, so retuning often needs mechanical deployment—an awkward constraint for satellites. Plasma is electrically conductive, so a filament can radiate if energy can be coupled into it without a physical contact that would disrupt the beam. Analysis of the experiment indicates a single-frequency laboratory proof; co-author Paul Franzon notes that low Earth orbit still has enough residual air to form plasma, but vacuum operation is untested.
Open questions include efficiency, noise, filament stability, and whether the same channel can receive. The paper does not show that laser steering already produces a practical radar sweep. Behavior in thinner air, wind, or at higher power remains unresolved.
Sources: ScienceDaily; IEEE Journal of Microwaves; North Carolina State University.
Caltech and Yale calculate the Kondo effect from real atomic structure
Scientists at Caltech and Yale report in Science a method to calculate the Kondo effect in specific metals rather than in simplified model Hamiltonians. They treated magnetic impurities almost as molecules, using quantum-chemistry tools on the full atomic and electronic structure of seven transition-metal atoms in copper. For most of those cases the predicted resistance upturn was up to two orders of magnitude more accurate than conventional orbital-reduced models. Senior author Garnet Chan frames the impurities as a prototype on the path to high-temperature superconductors and quantum magnets.
The Kondo effect appears when a magnetic atom in a metal is cooled below a characteristic temperature: resistance stops falling and then rises as conduction electrons screen the impurity spin. Kenneth Wilson and others solved the general many-body problem in the 1970s, but material-specific Kondo temperatures were not reliably computed from first principles. The new calculations keep the chemical complexity that model Hamiltonians discard.
The gap is that Kondo impurities are still a comparatively simple correlated system. Whether the same machinery can rank competing phases in cuprates or other quantum magnets is unproven. Experiment remains the test of whether “faithful predictive” descriptions of real materials are now in reach.
Sources: ScienceDaily; Science; California Institute of Technology.
Hubble niobium around white dwarf HS 0209+0832 hints at a second-generation planet
A Nature Astronomy study of 1999 Hubble spectra of white dwarf HS 0209+0832 reports a high abundance of niobium, an element not previously identified in any other white dwarf. Lead author Jamie Williams of the University of Warwick matched many previously unidentified lines using an updated chemical database; NASA’s retired FUSE mission independently showed strong niobium features. TESS brightness variations over four months are consistent with a Jupiter-sized body about 6 million kilometers from the star, far inside Mercury’s orbit. The proposed picture is a gas giant assembled from material expelled as the star died, now losing atmosphere onto the hot remnant.
Ordinary planets form with their stars. Niobium and other nuclei heavier than iron are not made by steady core fusion; they mark brief, extreme conditions in dying stars. If leftover ejecta later coalesced, the white-dwarf phase would not be a simple epilogue to planetary systems. The candidate appears to be shedding gas that could form a disk and pollute the stellar atmosphere, which would explain why Hubble sees niobium at the star.
The planet is not confirmed: TESS shows a periodic signal, not a resolved orbit or mass. Alternative sources of niobium and of the light curve have not been fully excluded. How common such objects are, and whether they persist once the white dwarf cools, remain open.
Sources: ScienceDaily; Nature Astronomy; NASA.