Every galaxy in the universe produces new stars , some running at a furious pace, while others barely ‘give birth’ to a few baby stars compared to massive stellar nurseries. Even throughout the life of a galaxy, the rate of star production changes. Finding out why this happens will help us understand how stars work in order to provide the ingredients for life, or not.
“Star formation determines the character of a galaxy,” said Mark Morris, UCLA professor of astronomy and astrophysics and co-author of the new study published in the journal Nature, in a statement. “And that’s something that matters to us because stars produce the heavy elements from which planets and life are made.”
At the center of our galaxy is a super massive black hole 4 million times the size of our Sun , which releases enormous amounts of energy as it consumes interstellar dust and debris. Using the European Space Agency’s XMM-Newton satellite, the team of astronomers found two escape channels that are funneling matter and energy away from this frenzied activity.
“We hypothesize that these (newly discovered) vents are escape conduits for all the energy released at the center of the galaxy,” Morris said.
Each plume of cosmic X-rays extends in opposite directions from the center, starting about 160 light-years away from massive black holes and stretching for more than 500 light-years.
The chimneys are fed by two huge structures that we already knew, the Fermi bubbles. They are cavities in galactic gas that are filled with high-speed particles and extend for about 25,000 light-years.
Astronomers have previously suggested that the bubbles are the remnants of massive supermassive black hole explosions or that the bubbles are launched by newborn stars. This discovery points to the possibility that the chimneys are the conduits for the high-speed particles within the bubbles.
“We know that the flows and winds of material and energy emanating from a galaxy are crucial in sculpting and altering the shape of that galaxy over time; they are key players in the way galaxies and other structures form and evolve. throughout the cosmos “, clear Gabriele Ponti from the Max Planck Institute for Extraterrestrial Physics in Garching (Germany) and leader of the work.
Even though our galaxy’s supermassive black hole is supermassive, it is quite ‘domestic’ compared to other galaxies. But that makes it the perfect test case to discover the process that is powering much more energetic galaxies.
“The amount of energy that comes out of the center of our galaxy is limited, but it is a very good example of a galactic center that we can observe and try to understand,” Morris concluded.
Referencia: An X-ray chimney extending hundreds of parsecs above and below the Galactic Centre, Nature (2019). DOI: 10.1038/s41586-019-1009-6 , https://www.nature.com/articles/s41586-019-1009-6
Crédito imagen: Gabriele Ponti/MPE/INAF and Mark Morris/UCLA
