In a groundbreaking revelation grounded in Einstein's century-old theories, astronomers have detected radiation emanating from the core of a distant quasar, where a supermassive black hole resides.

Led by Matus Rybak from Leiden University, the research team focused on the galaxy RXJ1131-1231, an active galaxy housing a quasar approximately 6 billion light-years away from Earth. RXJ1131-1231 has become a coveted target for astronomers due to a phenomenon known as gravitational lensing, predicted by Einstein's 1915 theory of general relativity.

Gravitational lensing occurs when a massive object, like another galaxy, distorts the fabric of spacetime, bending light from more distant sources. In this scenario, RXJ1131-1231 is magnified to appear three times its actual size. However, a fascinating twist arises with the occurrence of microlensing, which is similar but involves smaller, less massive objects.

While utilizing the Atacama Large Millimeter/submillimeter Array (ALMA) in northern Chile, the team observed three distinct images of RXJ1131-1231, each varying in brightness independently—a strong indicator of microlensing.

Rybak noted, "This is a smoking gun for microlensing, happening when a star is positioned between the galaxy and our observation point. We knew we had to delve deeper into this discovery."

The combination of macrolensing and microlensing created a stunning "double zoom" effect, unveiling details about RXJ1131-1231 that were previously concealed. Rybak compared it to stacking two magnifying glasses.

Upon revisiting RXJ1131-1231 five years after their 2015 study, the researchers captured the quasar’s brightness changing over years but were particularly intrigued by its flickering in millimeter wavelength radiation—a sign of tumultuous activity.

This unexpected radiation suggests the presence of a hot, magnetically charged doughnut-shaped band of material, or "corona," engulfing the supermassive black hole.

Known for their innovative microlensing studies since 2008, the team is now pushing the envelope further by examining the microlensing of millimeter radiation for the first time.

But the journey doesn't end here. The researchers are gearing up to utilize the Chandra X-ray telescope, employing microlensing to probe the temperature and magnetic fields near supermassive black holes. This deeper investigation could ultimately enhance our understanding of how these colossal entities shape their galactic environments.