A radio quiet zone is an area where

radio Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...

transmissions are restricted in order to protect a

radio telescope A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the r ...

or a communications station from radio frequency interference. The Radio Regulations of the

International Telecommunication Union The International Telecommunication Union (ITU)In the other common languages of the ITU: * * is a list of specialized agencies of the United Nations, specialized agency of the United Nations responsible for many matters related to information ...

(ITU) define interference as being detrimental to radio astronomy if it increases measurement uncertainty by 10%. In particular, the applicable regulation is known as ITU-R Recommendation RA.769, "Protection criteria used for radio astronomical measurements". Equipment that can cause interference includes

mobile phone A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This rad ...

television transmitter A television transmitter is a transmitter that is used for terrestrial television, terrestrial (over-the-air) television broadcasting. It is an electronic device that radiates radio waves that carry a video signal representing moving images, alon ...

s, and

CB radio Citizens band radio (CB radio) is a land mobile radio system, a system allowing short-distance one-to-many bidirectional voice communication among individuals, using two-way radios operating near 27 MHz (or the 11-m wavelength) in the high freq ...

s, as well as other

electrical equipment Electrical devices or electric devices are devices that functionally rely on electric energy ( AC or DC) to operate their core parts (electric motors, transformers, lighting, rechargeable batteries, control electronics). They can be contraste ...

. Quiet zones are located in areas that are sparsely populated, and may be enforced based on government legislation. A radio quiet zone is often divided into two zones: an exclusion zone where all radio emissions are prohibited, and a larger coordination zone of up to 100 km² where the power levels of radio transmissions are suitably limited so as not to interfere with the radio telescope. Formal radio quiet zones exist around many observatories, including the Murchison Radio-astronomy Observatory in Australia, the National Radio Astronomy Observatory and the Sugar Grove Station in West Virginia, United States (the United States National Radio Quiet Zone), the Itapetinga Radio Observatory in Brazil, and

MeerKAT The meerkat (''Suricata suricatta'') or suricate is a small mongoose found in southern Africa. It is characterised by a broad head, large eyes, a pointed snout, long legs, a thin tapering tail, and a brindled coat pattern. The head-and-body ...

in South Africa as examples. The ITU has recommended designating two locations in outer space as radio quiet zones: the shielded zone on the Moon's far side, and the Sun-Earth

Lagrangian point In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium (mechanics), equilibrium for small-mass objects under the gravity, gravitational influence of two massive orbit, orbiting b ...

L₂.

References

{{Reflist, 40em, refs= {{cite web, publisher=Australian Government, Department of Innovation, Industry, Science and, title=Radio quiet in the Mid West, url=http://www.ska.gov.au/Observatory/Pages/RadioQuiet.aspx, website=www.ska.gov.au, accessdate=13 April 2017, language=en {{cite web, title=National Radio Quiet Zone — Science Website, url=https://science.nrao.edu/facilities/gbt/interference-protection/nrqz/, website=science.nrao.edu, accessdate=13 April 2017, language=en {{cite journal, title=The importance of Radio Quiet Zone (RQZ) for radio astronomy, journal=AIP Conference Proceedings, date=8 May 2013, volume=1528, issue=1, pages=32–37, doi=10.1063/1.4803564, issn=0094-243X, last1=Umar, first1=Roslan, last2=Abidin, first2=Zamri Zainal, last3=Ibrahim, first3=Zainol Abidin, bibcode=2013AIPC.1528...32U, doi-access=free {{cite web, title=Radiobservatório do Itapetinga - ROI/INPE, url=http://www.cea.inpe.br/roi/zonasilencio.php, website=www.cea.inpe.br, accessdate=9 October 2017 {{citation , contribution=Radio quiet, please! - protecting radio astronomy from interference , last1=van Driel , first1=W. , postscript=. , title=The Role of Astronomy in Society and Culture, Proceedings of the International Astronomical Union, IAU Symposium, Volume 260, p. 457-464 , publisher=International Astronomical Union , date=June 2011 , volume=260 , page=457 , doi=10.1017/S1743921311002675 , bibcode=2011IAUS..260..457V , arxiv=0906.2268, s2cid=118632363 {{citation , postscript=. , contribution=Radio Quiet Zones , display-authors=1 , last1=Cohen , first1=J. , last2=Delgado , first2=G. , last3=Hardy , first3=E. , last4=Hasegawa , first4=T. , last5=Nyman , first5=L.-A. , title=Light Pollution: The Global View , editor1-first=H. E. , editor1-last=Schwarz , series=Astrophysics and Space Science Library , publisher=Kluwer Academic Publishers, Dordrecht , volume=284 , page=225 , date=April 2003 , doi=10.1007/978-94-017-0125-9_21 , bibcode=2003ASSL..284..225C , isbn=978-90-481-6242-0

External links

Radio quiet zones around observatories
CRAF Electromagnetic compatibility Radio astronomy

See also

References

External links