Earth-Based Telescope Detects Light from the Universe’s ‘Cosmic Dawn’ for the First Time
Understanding the cosmic dawn helps us understand the early stages of the cosmos and its origins.
The “Cosmic Dawn” is the early time in the universe’s history, around 800 million years after the Big Bang, when the first stars and galaxies formed and began to radiate light that put an end to the cosmic dark ages. Astronomers have observed this event using Earth-based observatories.
Because of the formation of huge stars and galaxies as well as the shaping of the universe’s composition and structure, this era was a crucial turning point in the universe’s evolution.
To learn more about the cosmic dawn, scientists have analysed observations of distant galaxies made by the James Webb Space Telescope (JWST). Understanding the genesis and evolution of galaxies is also aided by computational models.
“People believed that this was impossible to accomplish from the ground. “Microwave signals from the Cosmic Dawn are notoriously hard to measure, and astronomy is a technology-limited field,” study leader and Johns Hopkins professor of physics and astronomy Tobias Marriage said in a statement.
“Compared to space, ground-based observations have more difficulties. This measurement is a noteworthy accomplishment because those challenges have been overcome,” Marriage continued.
Understanding the cosmic dawn helps us understand the early stages of the cosmos and its origins.
The Cosmology Large Angular Scale Surveyor (CLASS), a collection of telescopes situated high in Northern Chile’s Atacama Desert, allowed the scientists to catch a fresh view of Cosmic Dawn.
CLASS’s primary goal is to observe the Cosmic Microwave Background (CMB), a cosmic remnant of an event that occurred shortly after the Big Bang.
The light, radio waves, radar, and satellites’ signals can all be distorted by variations in the atmosphere, weather, and temperature.
Given that its wavelength is in millimetres, the light from Cosmic Dawn is quite dim, which is evident given that it has been travelling to us for at least 13 billion years. Polarised microwave light produces a signal that is around a million times weaker.
The orientation of oscillations or vibrations in a wave, such light or electromagnetic waves, is referred to as polarisation. When light strikes an object and scatters off of it, this can occur.
“Polarisation occurs when light strikes your car’s hood and causes a glare. “You can wear polarised glasses to reduce glare and see clearly,” Yunyang Li, a team member and former Johns Hopkins PhD student, stated.
Yunyang, who was a fellow at the University of Chicago at the time this study was conducted, continued, “We can use the new common signal to determine how much of what we’re seeing is cosmic glare from light bouncing off the hood of the Cosmic Dawn, so to speak.”
