Scientists believe they have discovered a unique and powerful detector in the ongoing search for dark matter in our universe: exoplanets. Dark matter, according to astrophysicists, could be detected by measuring the effect it has on the temperature of exoplanets, which are planets outside our solar system.
Scientists believe they have discovered a unique and powerful detector in the ongoing search for dark matter in our universe: exoplanets. Two astrophysicists propose in a new paper that dark matter could be detected by measuring the effect it has on the temperature of exoplanets, which are planets outside our solar system. This could provide new insights into dark matter, a mysterious substance that cannot be directly observed but accounts for roughly 80% of the universe’s mass.
“We believe there are approximately 300 billion exoplanets waiting to be discovered,” said Juri Smirnov, a fellow at The Ohio State University’s Center for Cosmology and Astroparticle Physics. “Even finding and studying a small number of them could provide us with a wealth of previously unknown information about dark matter.”
Astrophysicists suggest dark matter could be detected by measuring the effect it has on the temperature of exoplanets, which are planets outside our solar system.
Smirnov collaborated on the paper with Rebecca Leane, a postdoctoral researcher at Stanford University’s SLAC National Accelerator Laboratory. The findings were published in the journal Physical Review Letters.
When the gravity of exoplanets captures dark matter, the dark matter travels to the planetary core, where it “annihilates” and releases its energy as heat, according to Smirnov. The more dark matter that is captured, the hotter the exoplanet should be. NASA’s James Webb Space Telescope, an infrared telescope set to launch in October and capable of measuring the temperature of distant exoplanets, could measure this heating.
“If there is anomalous heating associated with the dark matter on exoplanets, we should be able to detect it,” Smirnov said. According to Smirnov, exoplanets may be especially useful in detecting light dark matter, which is the dark matter with a lower mass. Researchers have yet to investigate light-dark matter through direct detection or other experiments.
Scientists believe that the density of dark matter increases toward the center of our Milky Way galaxy. If this is correct, scientists should discover that the closer planets are to the galactic center, the higher their temperatures should rise.
“It would be incredible if we could find something like that. Obviously, we would have discovered dark matter “According to Smirnov. Smirnov and Leane propose one type of search, which would involve looking for evidence of dark matter heating in gas giants – so-called “Super Jupiters” – and brown dwarfs close to Earth. One advantage of using planets like this as dark matter detectors is that, unlike stars, they do not undergo nuclear fusion, so there is less “background heat” that would make finding a dark matter signal difficult.
Aside from this local search, the researchers recommend looking for distant rogue exoplanets that are no longer orbiting a star. The absence of radiation from a star reduces interference that could obscure a signal from dark matter. One of the most appealing aspects of using exoplanets as dark matter detectors is that it does not necessitate the use of new types of instrumentation, such as telescopes, or searches that are not currently being conducted, according to Smirnov.
Currently, researchers have identified over 4,300 confirmed exoplanets, with an additional 5,695 candidates being investigated. Gaia, the European Space Agency’s space observatory, is expected to identify tens of thousands of more potential candidates in the coming years.
“With so many exoplanets being studied, we will have a tremendous opportunity to learn more about dark matter than ever before,” Smirnov said.
One advantage of using planets as dark matter detectors is that, unlike stars, they do not undergo nuclear fusion, so there is less background heat that would make it difficult to detect a dark matter signal. Aside from this local search, the team recommends looking for distant rogue exoplanets that are no longer orbiting a star. The absence of radiation from a star reduces interference that could obscure a signal from dark matter.
