Unveiling the First Stars: How Population III Stars Impact the 21cm Signal
Ventura et al. investigate how Population III stars influence the 21cm signal by using the meraxes semi-analytical model. They find that while Pop. III stars do not significantly alter reionization, their strong X-ray emissions heat the intergalactic medium at z ≥ 15, affecting the 21cm signal. Their simulations suggest that SKA1-low could detect these effects, potentially providing indirect evidence of the first stars in the universe.
Building a Window into the Galaxy: Designing a Home Radio Telescope for Detecting 21 cm Hydrogen Emission
Phelps’ study outlines the design of a low-cost, home-built radio telescope capable of detecting the 21 cm hydrogen line, allowing for the observation of neutral hydrogen distribution and motion within the Milky Way. By measuring Doppler shifts, the setup captures velocity data for hydrogen clouds, revealing details about the galaxy's structure and rotational dynamics. Through effective signal processing and interference reduction, this project makes advanced galactic observations accessible to amateur astronomers, helping map the motion of hydrogen gas in the Milky Way's spiral arms.