help

Two Questions About How Radio Telescopes Work

-- Dave | October 23, 2019

Question:

Two questions I have about radio astronomy.

1) Does a radio observatory focus on one specific and limited spot in space (What size)?
2) If a person stands directly in front of a radio telescope, can it cause physical harm?

Thank you.

-- Dave

Answer:

Regarding your first question, yes, a radio telescope makes measurements of a specific position in the sky. The size of this region is dependent upon how the radio telescope is designed and how it operates. For example, a radio telescope that operates as an interferometer (a bunch of telescopes electronically-connected to perform the measurements of the equivalent of one big telescope), the region in the sky that is measured can be quite small. A typical high-resolution measurement might only cover a few milli-arcseconds on the sky. On the other end of the scale, a radio telescope can also measure regions that are many 10s of degrees in size on the sky.

As for your second question, there is no harm due to radiation or other emission from a radio telescope to a person who stands in front of a radio telescope. Remember that radio telescopes, with very few exceptions, operate as receivers of radio signals, not as transmitters.

-- Jeff Mangum

The National Radio Astronomy Observatory is a facility of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc.
	Founded in 1956, the NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media.
	The U.S. National Science Foundation (NSF) is an independent federal agency created by Congress in 1950 "to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense..."
	AUI collaborates with the scientific community and research sponsors to plan, build, and operate cutting-edge facilities. We cultivate excellence, deliver value, enhance education, and engage the public.