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Technical Data of the Effelsberg Radio Telescope Reflector Diameter 100 m Aperture7,850 m² Number of Surface Elements (Panels)2,352 Accuracy of Surface<0.5 mm Focal Length in Prime Focus 30 m Secondary Mirror Diameter 6.5 m Resolution (Beam Width) 21cm (1.4 GHz) 9.4' (arc min) 3cm wavelength (10 GHz)1.15'(arc min) 3.5mm wavelength (86 GHz)10" (arc sec) Setting Accuracy of Track+/ mm Maximum Rotation Speed32°/min. Maximum Tilt Speed16°/min. Total Weight3,200 t Construction Period

Computer-generated image of an Airy disk. The outer rings of the Airy pattern have been enhanced in intensity. From Wikipedia

Full width at half maximum FWHM =1.03 /R

Computer-generated image of an Airy disk. The outer rings of the Airy pattern have been enhanced in intensity. From Wikipedia

/R

image at: /R /R

1.22 /R /R

Resolution Angular Resolution Resolving Power

Harry Kroto 2004 * * All stars are so far away that all rays from the same star are effectively parallel * Focus *

Harry Kroto 2004 * * * * The angular resolution  is determined by the angle between two just-resolved objects and is interference limited i.e.  = ( /R)

Harry Kroto 2004  * * d> R * * Essentially the opposite side of the triangle d > or ideally 1.22 

Harry Kroto 2004  * * R  = ( /R) * * The angular resolution  is determined by the angle between two just resolved objects and is interference limited i.e.  = ( /R)

Harry Kroto 2004  *  d

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

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image at: /R /R

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Computer-generated image of an Airy disk. The gray scale intensities have been adjusted to enhance the brightness of the outer rings of the Airy pattern.

The total project costs of about 34 million DM were essentially covered by a foundation (Volkswagen-Stiftung). Additional financing was provided by the state of Nordrhine-Westfalia and the Max-Planck-Gesellschaft. The federal ministery for science and technology ( Bundesministerium für Bildung und Forschung paid for some special parts of the equipment.Volkswagen-StiftungNordrhine-WestfaliaMax-Planck-Gesellschaft Bundesministerium für Bildung und Forschung Technical Data of the Effelsberg Radio Telescope Reflector Diameter100 m Aperture7,850 m² Number of Surface Elements (Panels)2,352Shape Accuracy of Surface< 0.5 mm Focal Length in Prime Focus30 m Secondary Mirror Diameter (Gregory-Reflector)6.5 m Aperture Stop - in Prime Focusf/0.3- in Secondary Focusf/3.85Angular Resolution (Beam Width) - at 21cm wavelength (1.4 GHz)9.4' (arc minutes)- at 3cm wavelength (10 GHz)1.15' (arc minutes)- at 3.5mm wavelength (86 GHz)10" (arc seconds) Azimuth Track Diameter64 m Setting Accuracy of Track+/ mm Azimuth Range480° Maximum Rotation Speed32°/min. Power Output of the 16 Azimuth-Drives17.5 kW each Radius of Elevation Gear Track28 mElevation Movementfrom 7° to 94° Maximum Tilt Speed16°/min. Power Output of the 4 Elevation-Drives17.5 kW each Total Weight3,200 t Construction Period Height of Track above Sea Level 319m Commencement of OperationAugust 1st, 1972 Constructed byArbeitsgemeinschaft KRUPP/MAN

The total project costs of about 34 million DM were essentially covered by a foundation (Volkswagen-Stiftung). Additional financing was provided by the state of Nordrhine-Westfalia and the Max- Planck-Gesellschaft. The federal ministery for science and technology ( Bundesministerium für Bildung und Forschung paid for some special parts of the equipment.Volkswagen-StiftungNordrhine-WestfaliaMax- Planck-GesellschaftBundesministerium für Bildung und Forschung Technical Data of the Effelsberg Radio Telescope Reflector Diameter100 m Aperture7,850 m² Number of Surface Elements (Panels)2,352Shape Accuracy of Surface< 0.5 mm Focal Length in Prime Focus30 m Secondary Mirror Diameter (Gregory-Reflector)6.5 m Resolution (Beam Width) - at 21cm wavelength (1.4 GHz)9.4' (arc minutes)- at 3cm wavelength (10 GHz)1.15' (arc minutes)- at 3.5mm wavelength (86 GHz)10" (arc seconds) Setting Accuracy of Track+/ mm Maximum Rotation Speed32°/min. Maximum Tilt Speed16°/min. Total Weight3,200 t Construction Period

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Computer-generated image of an Airy disk. The outer rings of the Airy pattern have been enhanced in intensity. From Wikipedia

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

From Wikipedia, the free encyclopedia (Redirected from Airy pattern)Airy pattern Longitudinal sections through a focused beam with (top) negative, (center) zero, and (bottom) positive spherical aberration. The lens is to the left. In optics, the Airy disk (or Airy disc) and Airy pattern are descriptions of the best focused spot of light that a perfect lens with a circular aperture can make, limited by the diffraction of light.opticslensaperturediffractionlight The diffraction pattern resulting from a uniformly-illuminated circular aperture has a bright region in the center, known as the Airy disk which together with the series of concentric bright rings around is called the Airy pattern. Both are named after George Biddell Airy, who first described the phenomenon. The diameter of this pattern is related to the wavelength of the illuminating light and the size of the circular aperture.George Biddell Airy The most important application of this concept is in cameras and telescopes. Due to diffraction, the smallest point to which one can focus a beam of light using a lens is the size of the Airy disk. Even if one were able to make a perfect lens, there is still a limit to the resolution of an image created by this lens. An optical system in which the resolution is no longer limited by imperfections in the lenses but only by diffraction is said to be diffraction limited.diffraction limited The Airy disk is of importance in physics, optics, and astronomy.physicsopticsastronomy

Harry Kroto 2004 HOMEWORK Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 HOMEWORK Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  or R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120 GHz ≡ = 3x10 10 /120 x 10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120GHz ≡ = 3x10 10 /120x10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120GHz ≡ = 3x10 10 /120x10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120GHz ≡ = 3x10 10 /120x10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120GHz ≡ = 3x10 10 /120x10 9 cm = 0.25 cm

Harry Kroto 2004 Consider the resolution  = ( /R) of: a) The Bonn 100m Radio Telescope operating at the 21cm H spin flip line b) Kitt Peak 12m Radio Telescope operating at the J=1 - 0 rotational line of CO at 120 GHz c) Galileo's 2cm optical telescope observing Saturn in the visible at 500nm.  R (cm) R(cm) /R  (rad)  ( o ) 21cm 100m / x GHz 12m /12x x nm 2cm 500x x10 -5 /2 2.5x NB  = c = 3x10 10 cm thus 120GHz ≡ = 3x10 10 /120x10 9 cm = 0.25 cm