In the center of most galaxies inhabits a supermassive black hole that emits large amounts of radiation while devouring everything around it.
In others, their ‘monster’ remains asleep and goes unnoticed. However, astronomers have detected unprecedented activity in six of these ‘dead‘ galaxies.
A team of researchers observed a group of LINER galaxies , which are characterized by having heated gas in their center and expelling very little radiation, and saw six of them “ignite” in a period of nine months.
The scientists used the Zwicky Transient Facility (ZTF), a new camera installed at the Palomar Observatory in California , to examine several LINER galaxies. In addition, they used data from the Hubble, Spitzer and Swift telescopes, and US observatories. UU.
When analyzing all this information, they realized that six galaxies went from their “weak” state to being incredibly energetic, forming what is known as quasars at a disconcerting speed.
The quasars are phenomena that often arise when the black hole core (center) of a galaxy starts to gobble up all matter in its path. This causes a disk that spins at high speeds to form around and releases such an amount of energy that its brightness can be detected from Earth.
“The theory suggests that a quasar should take thousands of years to activate, but these observations suggest that it can happen very quickly (nine months).
“It tells us that the theory is completely wrong,” said Suvi Gezari, associate professor of astronomy at the University of Maryland and co-author of the study.
The team of researchers does not explain why these black holes went from being ‘sleeping beauty’ to ‘hungry spawn’ so suddenly.
In addition, they have encountered another mystery: the brightness only came from the gas and debris closest to the center of these LINER galaxies, while the quasars previously observed shone in regions far from the nucleus.
One of their hypotheses is that they have just captured the moments before and after the birth of a quasar, which means an unmatched achievement for astronomers, since it would allow them to know much more about the evolution of galaxies.
“It is surprising that any galaxy can change its appearance on human time scales,” said Sara Frederick, an astronomer at the University of Maryland and first author of the article.
“These changes are happening much faster than we can explain with the current theory of quasar,” he added.