Cosmic Origins of Life: ngVLA Key Science Goal 2
January 31st, 2019
The ngVLA will detect predicted, but as yet unobserved, complex prebiotic species that are the basis of our understanding of chemical evolution toward amino acids and other biogenic molecules. The ngVLA will enable the detection and study of chiral molecules, testing ideas on the origins of homochirality in biological systems. The detection of such complex organic molecules will provide the chemical initial conditions of forming solar systems and planets.
Simulations of three biogenic molecules in a typical hot core source, based on existing upper limits, assuming T = 80 K, dV = 3 km/s, and a 5" source. The ngVLA’s sensitivity to detect these lines for the first time in a 10 hour-long integration is shown as a dashed blue line. The key capabilities for this science are high-sensitivity and continuous spectral coverage at frequencies of 20-50 GHz. High spatial resolution is also necessary to remove spectral confusion created by Doppler line broadening and variation of physical conditions within the beam. For comparison, diminishing returns with a very large single-dish facility such as the GBT are hit at a sensitivity of approximately 2,500 microJy, and pushing below that limit would require 100s to 1000s of hours of observations. This makes the ngVLA uniquely suited to carry out this science, as well as other chemistry-related science such as resolving snow-lines in protoplanetary disks.