Scientists Detect Flickering Signal From Milky Way’s Supermassive Black Hole

Scientists detected strange signals originating from the center of Earth’s neighborhood, the Milky Way Galaxy. According to their investigation, the flickering signals were coming from the galaxy’s central supermassive black hole.

The scientists made their discovery using the Atacama Large Millimeter/Submillimeter Array Telescope in Chile. Details of their discovery were presented in The Astrophysical Journal Letters.

A supermassive black hole known as Sagittarius A*, which is believed to be about 4 million times more massive than the Sun, resides at the center of Milky Way. Although it cannot be observed directly since it absorbs everything including light, the black hole produces certain emissions that scientists can observe and study.

Recently, a team of scientists from Japan came across periodic flickers in millimeter waves coming from Sagittarius A*. Using the ALMA telescope, the scientists observed the center of Milky Way to collect data on the flickering signals.

“It has been known that [Sagittarius A*] sometimes flares up in millimeter wavelength,” the study’s lead author Yuhei Iwata of the Keio University in Japan said in a statement. “This time, using ALMA, we obtained high-quality data of radio-wave intensity variation of [Sagittarius A*] for 10 days, 70 minutes per day. Then we found two trends: quasi-periodic variations with a typical time scale of 30 minutes and hour-long slow variations.”

Based on their observations, the emissions or the flickering signals seems to be coming from Sagittarius A*’s accretion disk, which is the hot gaseous disk swirling around the black hole.

According to the scientists, the timescales of the signals can be compared to the orbital period of the accretion disk’s innermost edge. As noted by the scientists, this region rotates around the black hole at a much faster rate that the orbital period of Mercury, which is the innermost planet in the Solar System.

The scientists believe that the flickering signals coming from the center of Milky Way may have been caused by the rotation of the accretion disk around Sagittarius A*.

“The variation of the emission itself provides compelling insight for the gas motion,” the scientists stated. “We may witness the very moment of gas absorption by the black hole with a long-term monitoring campaign with ALMA.”