If you live in a certain part of the United States, tornadoes are an annual threat carving a trail of destruction across tornado alley. In 1996, Twister introduced the world to stormchasing, the exciting and slightly unhinged practice of chasing down tornadoes to learn more about them. Nearly 30 years later, we collectively went stormchasing once again in Twisters, a standalone sequel which upped the danger and damage, complete with fire tornadoes.
If there’s ever a third film in the Twister franchise, filmmakers might need to raise the stakes again. Fortunately for fans of blockbuster action, astronomers recently discovered evidence of “space tornadoes” spinning around the black hole at the center of our galaxy, according to a study published in Astronomy & Astrophysics.
How astronomers discovered space tornadoes in the galactic center
Rather than using the fictional Dorothy device to measure these tornadoes from the inside, astronomers used the sensitive, high-resolution instruments at the Atacama Large Millimeter/submillimeter Array (ALMA), in the Atacama Desert, Chile.
The collection of 66 radio telescopes is a partnership between the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. Together, an international team of scientists observed the star-forming ring of gas and dust known as the Central Molecular Zone (CMZ).
The intensity of gravitational forces around a black hole sends gas, dust, and other material spinning violently around the event horizon, sending shockwaves through the morass. The CMZ is an area of intense interest, and these observations provided a view of the galactic center 100 times sharper than ever before. In their highly detailed observations, astronomers discovered previously unseen molecular filaments spinning out from the CMZ.
Mysterious space tornadoes swirl around the galactic core
Consider the way that flowing water in a stream moves sand and stones of different sizes and shapes in different ways. By looking at the distribution of sediments, you can tell something about the flow of the water. Something similar happens in the gas and dust around a black hole.
Different molecules are impacted by the forces around a black hole in different ways and they can be used as tracers to track different mechanisms. The newly discovered filaments are made of silicon monoxide (and eight other molecules) which are useful for detecting shockwaves.
“When we checked the ALMA images showing the outflows, we noticed these long and narrow filaments spatially offset from any star-forming regions. Unlike any objects we know, these filaments really surprised us. Since then, we have been pondering what they are,” said lead author Kai Yang, in a statement.
These filaments are unlike anything astronomers have seen before and don’t fit the profile of any other known type of dense gas filament, suggesting some previously unknown relationship or mechanism in the CMZ.
“Our research contributes to the fascinating Galactic Center landscape by uncovering these slim filaments as an important part of material circulation. We can envision these as space tornados: they are violent streams of gas, they dissipate shortly, and they distribute materials into the environment efficiently”, said corresponding author Xing Lu.
The filaments also suggest the existence of a cyclical material circulation process. First, shocks create filaments, releasing silicon monoxide and other complex molecules into the interstellar medium. Eventually, the filaments dissipate, the molecules freeze into dust grains, and the cycle starts over again.
Researchers hope that future observations will not only confirm the existence of these filaments in the CMZ but will also help to uncover their origin and influence on the galactic core.
Before we head to space for a third installment, check out Twisters, now streaming on Peacock!