Scientists from the Search for Extraterrestrial Intelligence Institute (SETI – USA) have discovered a “treasure” in the data left by the Arecibo Observatory.
According to Live Science, SETI scientists successfully unlocked the secrets of signals from the “cosmic lighthouse”, powered by dead stars, while analyzing data collected by the Arecibo Observatory before its collapse.
Arecibo was one of the most powerful radio observatories in the world, famous for its mission to send messages to the M13 star cluster in hopes that extraterrestrials would receive them.
However, on December 1, 2020, the main 305-meter dish of Arecibo shattered due to a cable failure, ending nearly four decades of service.
The Arecibo International Observatory located in Puerto Rico with its main dish shattered after the 2020 incident due to the combined effects of a storm and deterioration – (Photo: GIZMODO).
Reviewing the vast data archive left by this sky-watching warrior, the team led by Dr. Sofia Sheikh from the SETI Institute focused on how signals from pulsars are distorted as they travel through space.
Pulsars are a type of neutron star, remnants of massive stars that have died. Compared to other neutron stars, pulsars are more powerful and peculiar because they rotate extremely fast—up to 700 times per second—and continuously emit intense beams of radiation sweeping through space as they spin.
Arecibo captured many “signals from the dead” before its collapse. Accompanying this was a significant skepticism: It seemed that something was interfering with these signals on their journey to Earth.
Researchers specifically examined 23 pulsars, including 6 that had never been studied before.
They discovered the interference in these signals, a finding of great value for astronomy, although not due to extraterrestrials as expected.
This interference is referred to as “interstellar diffraction scintillation” (DISS), caused by charged particles in the interstellar medium, which create distortion in the radio signals transmitted from the pulsars to Earth-based observatories.
The study also showed that the bandwidth of the pulsar signals is broader than current models suggest, indicating that to continue accurate cosmic research, humanity needs to adjust some widely accepted cosmological models.
Additionally, galactic structures such as the spiral arms of the Milky Way Galaxy also contribute to DISS.
Understanding how pulsar signals work is crucial because, when considered over large arrays, these highly precise periodic signals from pulsars can be used as a timing mechanism.
For example, this mechanism is used as a foundation to measure tiny distortions in space-time caused by gravitational waves.
“Years after the collapse of Arecibo, its data continues to unlock important information that could enhance our understanding of the galaxy and improve our ability to study phenomena like gravitational waves,” the authors wrote in The Astrophysical Journal.
