Porphyrion Giant Jet System (IMAGE) California Institute of Technology Caption An artist's illustration of the longest black hole jet system ever observed. Nicknamed Porphyrion after a mythological Greek giant, these jets span roughly 7 megaparsecs, or 23 million light-years. That is equivalent to lining up 140 Milky Way galaxies back-to-back. Porphyrion dates back to a time when our universe was less than half its present age. During this early epoch, the wispy filaments that connect and feed galaxies, known as the cosmic web, were closer together than they are now. Consequently, this colossal jet pair extended across a larger portion of the cosmic web compared to similar jets in our nearby universe. Porphyrion's discovery thus implies that jets in the early universe may have influenced the formation of galaxies to a greater extent than previously believed. Credit E. Wernquist / D. Nelson (IllustrisTNG Collaboration) / M. Oei Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.