Observational time refers to a period during which an astronomer or other observer is scheduled to use a telescope, observatory or other instrument for making observations. Full definition
Breakthrough Listen allotted tens of hours of observational time on the Green Bank Telescope to recording radio emissions from FRB 121102, and last August 26 detected 15 bursts over a relatively short period of five hours. (sciencedaily.com)
To better understand the work lives of principals, this study uses observational time - use data for all high school principals in Miami - Dade County Public Schools. (caldercenter.org)
This is precisely the problem with comparing short observational time series and model projections that was exemplified in the January 10 blog post («A Spot Check on Global Warming») by your colleague John Tierney. (dotearth.blogs.nytimes.com)