José Antonio García Barreto
Radio Telescopes in the world: photo gallery
Several photos of different single parabolic antennas used as radio telescopes
are presented.
Angular Resolution of a (Radio) Telescope
La hability of a radio telescope to observe details from an object in the
sky is called, in the astronomical vocabulary, angular resolution.
The angular resolution of a single (parabolic in shape) radio telescope is defined
as proportional to the ratio between the wavelength (of the incoming radiation)
over the diameter de la aperture of the parabola. Thus, if wavelentgh is "lambda"
and diameter is "D", the angular resolution (angle theta) is theta=lambda/D multiplied
by a constant, say k. Theta is given in radians (1 radian is 57.2958 degrees).
For example: if lambda is 2.7mm [characteristic wavelength of the molecule carbon
monoxide, CO, in its transition between its rotational levels from level J=1 to
J=0] observed with a (single) radio telescope of 10.4m (de OVRO), the angular
is (if k=1.22) theta=0.000316 radians equivalent to theta=65 seconds of arc.
Angular Resolution of a (Radio) Interferometer
The angular resolution of an interferometer to observe detail from an
object in the sky is defined as proportional to the ratio between wavelength
over distance from one antenna to the other. Thus if the separation distance
between two antennas is "d", the angular resolution (angle theta) es theta=k
lambda/d.
For example: if lambda is 2.7mm observed with the radio interferometer
at OVRO with a maximum separation of 200m the angular resolution is (if k=1.22)
theta=0.0000165 radians equivalent to theta=3.4 seconds of arc.
- Radio Telescope
100m diameter in Effelsberg Germany, belongs to Max Planck Institute fur
Radio Astronomie. (Picture from the author JAGB)
- Azimuthal
system in the 100m radio telescope de Effelsberg (Picture from the author JAGB)
- Radio Telescope
42.7m (140 feet) diameter in West Virginia, USA, belongs to
National Radio Astronomy Observatory, NRAO, USA) (Picture: NRAO)
- Radio
Telescope 305m diameter in Arecibo, Puerto Rico, operated by National Astronomy and
Ionosphere Center, Cornell University (Picture from author JAGB)
- Receiver room
at the 305m radio telescope in Arecibo, Puerto Rico, operated by National Astronomy and
Ionosphere Center, Cornell University(Picture from author JAGB, )
- Individual
panel of the 305m radio telescope in Arecibo, Puerto Rico, operated by National
Astronomy and Ionosphere Center, Cornell University)(Picture from the
author JAGB)
- Radio Telescope
15m diameter belongs to the Institute de Radio Astronomie Milimetrique (IRAM) in
France. IRAM is a German, French, Spanish consortium. (Picture from the author
JAGB)
- Radio Telescope
30m diameter belongs to the Institute de Radio Astronomie Milimetrique (IRAM) in
France. IRAM is a German, French, Spanish consortium.(Picture from the author
JAGB)
- Back
structure of the Radio Telescope 30m diameter; it belongs to the Institute de
Radio Astronomie Milimetrique (IRAM) in Spain. IRAM is a German, French, Spanish
consortium.(Picture from the author JAGB)
-
Secundary Mirror of the 30m Radio Telescope belongs to the Institute de Radio Astronomie Milimetrique (IRAM) in
Spain. IRAM is a German, French, Spanish consortium.(Picture from the author
JAGB)
-
Radio Telescopes each 15m de diameter forming a radio interferometer in France.
It belongs to the Institute de Radio Astronomie Milimetrique (IRAM) in
France. IRAM is a German, French, Spanish consortium.(Picture from the author
JAGB)
-
Stations and rail tracks of the radio interferometer. It belongs to the Institute de Radio Astronomie Milimetrique (IRAM) in
France. IRAM is a German, French, Spanish consortium.(Picture from the author
JAGB)
-
(Radio Telescope) Original antenna used by Dr. Karl Jansky. (Picture:
National Radio Astronomy Observatory, USA)
-
Back Structure of the Radio Telescope 76.2m diameter in Jodrell Bank, England
(Picture from the author JAGB)
-
Reflector of the Radio Telescope 76.2m diameter that belongs to Jodrell Bank,
in England (Picture from the author JAGB)
- 27
radio telescopes forming the radio interferometer known as Very Large Array.
It belongs to the National Radio Astronomy Observatory, NRAO, in Nuevo Mexico, USA. (Picture: NRAO, USA)
- Radio
Telescopes of 10.4m diameter forming the Radio Interferometer in OVRO, California,
USA. OVRO means Owens Valley Radio Observatory, operated and owned by
California Institute of Technology (CALTECH), in Pasadena, Calif. USA
(Picture: OVRO, Caltech, USA)
- Radio
Telescopes 6m diameter forming the Radio Interferometer known as BIMA, in
California, USA. BIMA is a consortium of the University of California in Berkeley,
University of Illinois, University of Maryland, USA (Picture: Consortium BIMA)
- Esquematic
drawing of the system of 10 radio telescopes forming a Giant Radio
Interferometer with large separation distances between the antennas. Forms the
so called Very Long Baseline Array operated by the National Radio Astronomy
Observatory, USA (Picture NRAO)
Back to Main Page J.A. García Barreto .
Back to Main page of Instituto de Astronomía, UNAM .
J. Antonio García-Barreto / tony@astroscu.unam.mx
(Created: August 14, 1998| Last Update: July 15, 2003)
