The low rate of star formation in the CMZ has puzzled astronomers for decades. Because the physical conditions there differ from those in normal giant molecular clouds, astronomers generally have concluded that the responsibility must lie with some combination of their properties, in particular the high values of gas density, temperature, pressure, motion, and magnetic field strength. CfA astronomers Qizhou Zhang, Cara Battersby, and Eric Keto, and their colleagues used the Submillimeter Array (SMA) to undertake a large and comprehensive study of the CMZ in search of answers. They discovered a sample of thirteen high-mass cores with between 50-2200 solar-masses of material that could be incipient young stars, and two objects that appear to be previously unknown young, massive stars. The SMA also observed the spectral lines of the molecules formaldehyde and methyl cyanide to measure the temperature of the gas and its kinematics, including turbulent motions. The scientists conclude, in agreement with previous speculation, that the turbulent environment of the CMZ is responsible for inhibiting star formation there. Reference: “Star formation in a high-pressure environment: an SMA view of the Galactic Centre dust ridge” by D L Walker, S N Longmore, Q Zhang, C Battersby, E Keto, J M D Kruijssen, A Ginsburg, X Lu, J D Henshaw, J Kauffmann, T Pillai, E A C Mills, A J Walsh, J Bally, L C Ho, K Immer and K G Johnston, 21 February 2018, Monthly Notices of the Royal Astronomical Society.DOI: 10.1093/mnras/stx2898
