Most astronomers spend only a few weeks each year making observations with optical telescopes, radio telescopes, and other instruments. Contrary to the popular image, astronomers almost never make observations by looking directly through a telescope because enhanced photographic and electronic detecting equipment can see more than the human eye. However, all physics involves the same fundamental principles, so specialties may overlap, and physicists may switch from one subfield to another. Also, growing numbers of physicists work in combined fields such as biophysics, chemical physics, and geophysics. Research and development work is an integral part of most physicists' jobs.
Physicists often work regular hours in laboratories and offices.
At times, however, those who are deeply involved in research may work long or irregular hours. Most do not encounter unusual hazards in their work. Some physicists work away from home temporarily at national or international facilities with unique equipment such as particle accelerators. Astronomers who make observations may travel to observatories, which are usually in remote locations, and routinely work at night. Employment Physicists and astronomers held nearly 21,000 jobs in 1992.