Two studies led by NASA astrophysicists show in new detail how the future space observatory LISA (Laser Interferometer Space Antenna) could reveal a brand-new population of exoplanets — worlds beyond our Solar System — across the Milky Way. The papers were published on Tuesday, November 10, 2026, in The Astrophysical Journal.
How a planet leaves its mark on gravitational waves
The most common source of signals for LISA is expected to be double white dwarf systems — pairs of white dwarfs in tight orbits. If an exoplanet also orbits one of these systems, its gravity makes the pair wobble slightly, and that presence becomes imprinted on the gravitational-wave signal in a way scientists will be able to uncover, explains Casey McGrath, a researcher at the University of Maryland and NASA's Goddard Space Flight Center and author of the first study.
The method resembles the radial velocity technique already used to find exoplanets from starlight. For LISA, the modulation will appear as sidebands — secondary signals at frequencies slightly above and below the main frequency. McGrath likens the effect to modern radio, where some of the energy of a main frequency forms sidebands that carry the message: in gravitational waves, the sidebands carry the message about a planet's presence.
A brand-new population of planets
Exoplanets have already been found around a few isolated white dwarfs, but none has yet been found around a binary white dwarf. LISA's detections would therefore represent a distinct, previously unknown population of exoplanets. According to the studies, the observatory could detect a Jupiter-mass planet in such systems thousands of light-years away.
Astronomers estimate that the Milky Way contains 10 million double white dwarf systems with orbital periods of less than an hour, which generate gravitational waves in the right range for LISA to find. The observatory is expected to resolve about 10,000 individual systems, plus around 100 mixed binaries — with white dwarfs, neutron stars, or black holes.
The Webb telescope will confirm the detections
The second study describes how to confirm these planets with the James Webb Space Telescope. A planet in a double white dwarf system produces a larger share of infrared light than expected from the stars alone, and Webb's instruments can detect this infrared excess out to at least 500 light-years. In a test-case system at that distance, Webb could detect an exoplanet about five times Jupiter's mass, while LISA, under ideal circumstances, could detect a sub-Jupiter planet.
The LISA observatory
LISA will consist of three spacecraft following Earth in its orbit around the Sun, in a vast triangular formation 2.5 million kilometers on each side. Each spacecraft will carry two telescopes that use infrared laser beams to measure minuscule changes — smaller than the width of a helium atom — in their relative distances: the signals of passing gravitational waves.
The mission is led by the European Space Agency (ESA), with launch slated for the mid-2030s, and NASA is contributing telescopes, the laser system, charge management devices, and data analysis. The possibility of detecting exoplanets around double white dwarf systems with LISA was first proposed by Japanese astronomer Naoki Seto in 2008.
Sources: NASA — NASA Scientists Show How Gravitational Waves Can Reveal New Worlds; Phys.org — How ripples in space-time can reveal new exoplanets; Casey McGrath, The Astrophysical Journal (2026), DOI: 10.3847/1538-4357/aea216; Casey McGrath et al., The Astrophysical Journal (2026), DOI: 10.3847/1538-4357/aea07d.
Image credit: artist's impression of the James Webb Space Telescope, ESA/Hubble. Webb is the telescope that will be able to confirm the planets detected by LISA, by measuring the infrared excess of these systems.
Transparency: this article was produced with the assistance of artificial intelligence, based on cross-checking public posts and internet sources, including NASA's official release and science press coverage. We recommend consulting the original sources to confirm the details.
By Muse
