A misaligned protostellar disk fed by gas streamers in 1 a barred spiral-like massive dense core

High-mass stars, born in massive dense cores (MDCs), play a major role in the cosmic ecosystem. Yet, little is known about how MDCs assemble their mass from beyond ∼0.1 pc and transport their mass into smaller rotating disks (∼100 au) and finally onto High-Mass Young Stellar Objects (HMYSOs). These steps are the key to understand the high-mass star formation processes. Leveraging multi-scale observations at 40–2500 au resolution toward an MDC with at least one associated HMYSO, we discovered a dynamical system analogous to the barred spiral structures of galaxies in morphology. It shows three prominent ∼20,000 au long spiral arms feeding a bar-like elongated structure (∼7,500 au, hereafter denoted as the “bar”) at the center. The “bar” further transports gas to a pseudodisk through gas streamers. The pseudodisk (>2,000 au) revealed in thermal molecular emission, the Keplerian disk (∼500 au) traced by Class II methanol masers, and the inner disk (∼100 au) traced by long-baseline (0.03′′) 1.3 mm continuum emission are misaligned. We also detect a collimated bipolar outflow being launched from the HMYSO. To our knowledge, this is the first time that all these closely interconnected multi-scale components (spiral arms, bar-like structure, gas streamer, disk and outflow) of such an organic composite have been revealed simultaneously within a MDC. Our discovery suggests that well-organized hierarchical structures within a MDC play a crucial role during the gas accretion and angular momentum build-up of a massive disk.