data, studies, study, learning, evidence, methods, techniques, research, skills, results, method, errors, work, material, astronomy, measures, procedures, error, terms, approach, science, period, facts, constraints, technique, analysis, consequences, knowledge, systems, basis, records, assessment, notes, procedure, tests, equivalence, language, statements, reports, powers, units, instruments, test, fact, support, approaches, record, cosmology, findings, designs, categories, adequacy, program, sciences, tools, unit, accuracy, base, strategies, measure, instrument, periods, methodology, bias, concepts, conditioning, limits, tool, experiences, series, selection, astronomer, assessments, report, uncertainties, ratings, network, difficulties, astronomers, criteria, confirmation