Researchers say the first stars left behind distinctive flares that can be detected by a new generation of space telescopes.
Astronomers at Yale and the University of Hong Kong have proposed a new strategy for finding the universe’s first stars — by looking for signs of their final, fiery flares.
For years, scientists have searched for direct evidence of “Population III” stars, the first generation of stars that lit up the universe just a few hundred million years after the
“We realized that the fireworks created by the ripping apart of a Population III star that strays too close to a
Detecting Cosmic Events Across Billions of Light Years
In the new study, the researchers suggest that if a “Population III” star encounters a black hole, the resulting “tidal disruption event” (TDE), in which the black hole tears the star apart, would create a particularly bright flare — bright enough and long-lived enough to reach across billions of light years to reach Earth today. What’s more, the flare would have an identifiable “signature” that is discernable to astronomers.
“As the energetic photons travel from a very faraway distance, the timescale of the flare will be stretched due to the expansion of the universe,” said astronomer Jane Dai of the University of Hong Kong, principal investigator of the research team. “These TDE flares will rise and decay over a very long period of time, which sets them apart from the TDEs of solar type stars in the nearby universe.”
Importantly, the wavelength of the flares’ light is also stretched, according to the study’s first author, Rudrani Kar Chowdhury from the University of Hong Kong. “The optical and ultraviolet light emitted by the TDE will be transferred to infrared wavelengths when reaching the Earth,” she said.
And that infrared light can be detected, the researchers said.
The Role of Modern Telescopes in Star Detection
They say that two flagship DOI: 10.3847/2041-8213/ad41b7