telescopes donna kubik phys162 spring, 2006. purpose of telescopes to do what our eyes cannot...
TRANSCRIPT
![Page 1: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/1.jpg)
Telescopes
Donna Kubik PHYS162 Spring, 2006
![Page 2: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/2.jpg)
Purpose of telescopes
To do what our eyes cannot
Collect photons (from radio to gamma ray)
Achieve higher resolution
Record the received photons
Images
Spectra
![Page 3: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/3.jpg)
Recording
Rarely are your eyes usedto directly look througha telescope, even for an
optical telescope!
![Page 4: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/4.jpg)
Types of EM radiation
Astronomers have constructed telescopes that have detected all forms of EM radiation, both visible and non-visible, emitted by objects in space.
![Page 5: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/5.jpg)
Types of EM radiation
Radio
Millimeter
Sub-millimeter
Infrared
Optical
Ultraviolet
Xray
Gamma ray
![Page 6: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/6.jpg)
Types of astronomers
Radio astronomers
Millimeter astronomers
Sub-millimeter astronomers
Infrared astronomers
Optical astronomers
Ultraviolet astronomers
X-ray astronomers
Gamma ray astronomers
![Page 7: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/7.jpg)
Types of astronomy
Radio astronomy
Millimeter astronomy
Sub-millimeter astronomy
Infrared astronomy
Optical astronomy
Ultraviolet astronomy
X-ray astronomy
Gamma ray astronomy
![Page 8: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/8.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 9: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/9.jpg)
The telescopes look very different!
Effelsberg radio telescope, Germany
![Page 10: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/10.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 11: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/11.jpg)
The telescopes look very different!
NRAO 12 meter telescope, Kitt Peak Observatory
![Page 12: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/12.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 13: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/13.jpg)
The telescopes look very different!
Sub Millimeter Telescope (SMT), Mt. Graham, AZ
![Page 14: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/14.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 15: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/15.jpg)
The telescopes look very different!
SIRTF Space Infra Red Telescope Facility
![Page 16: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/16.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 17: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/17.jpg)
The telescopes look very different!
Yerkes 40-inch telescope,Williams Bay, WI
World’s largest refractor
![Page 18: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/18.jpg)
KPNOKitt Peak National Observatory
2.1 meter telescope
The telescopes look very different!
![Page 19: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/19.jpg)
The telescopes look very different!
Keck optical telescopes
Mauna Kea, Hawaii
![Page 20: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/20.jpg)
The telescopes look very different!
HST Hubble Space Telescope
![Page 21: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/21.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 22: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/22.jpg)
The telescopes look very different!
HUT Hopkins Ultraviolet Telescope
![Page 23: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/23.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 24: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/24.jpg)
The telescopes look very different!
XMM Xray MultiMirror telescope
![Page 25: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/25.jpg)
Types of telescopes
Radio telescopes
Millimeter telescopes
Sub-millimeter telescopes
Infrared telescope
Optical telescopes
Ultraviolet telescopes
X-ray telescopes
Gamma ray telescopes
![Page 26: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/26.jpg)
The telescopes look very different!
CGRO Compton Gamma Ray Observatory
![Page 27: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/27.jpg)
And…..the images from the different types of telescopes look very
different!
![Page 28: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/28.jpg)
The images look very different
Ultraviolet Visible Infrared
NGC1512 barred spiral
galaxy
HST images
![Page 29: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/29.jpg)
The images look very different
M87 giant elliptical galaxy in Virgo cluster
![Page 30: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/30.jpg)
The images look very different
Cygnus A
X-ray (Chandra)
Radio
![Page 31: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/31.jpg)
The images look very different
red=xraygreen=opticalblue=UV
30 DoradusOpen cluster
in LMC
![Page 32: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/32.jpg)
Types of EM radiation
Why do the telescopes and images look so different?
![Page 33: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/33.jpg)
Types of EM radiation
The difference between each type of EM radiation in each region is its energy!
![Page 34: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/34.jpg)
Types of EM radiation
Because of their different energies, each type of EM radiation interacts differently with matter.
That’s why the telescopes look so different.
That’s why the images look so different.
And that’s also why the telescopes are located at very different places...
![Page 35: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/35.jpg)
Types of EM radiation
The energy (or freq or wavelength) determines how the radiation will react with the atmosphere.
![Page 36: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/36.jpg)
Atmospheric windowsRadio,
millimeter,sub-millimeter
Infrared andoptical
Ultravioletxrays, gamma rays
Water and CO2Ozone and oxygen
![Page 37: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/37.jpg)
Location of radio, millimeter, and sub-millimeter telescopes
Radio
Ground-based
Millimeter wave
High and dry
Sub-millimeter
Even higher and drier
![Page 38: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/38.jpg)
Location of infrared and optical telescopes
Infrared
High and dry
Optical
Ground-based
![Page 39: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/39.jpg)
Location of ultraviolet, xray, and gamma ray telescopes
Ultraviolet
Space
Xray
Space
Gamma ray
Ground-based and Space
![Page 40: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/40.jpg)
Types of EM radiation
Astronomers often group the different types of EM radiation into 3 groups according to their energy.
![Page 41: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/41.jpg)
Types of EM radiation
Low frequency/long wavelength LOW ENERGY
Radio
Millimeter
Sub-millimeter
Mid frequency/mid wavelength MID ENERGY
Infrared
Optical
High frequency/short wavelength HIGH ENERGY
Ultraviolet
X-ray
Gamma ray
![Page 42: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/42.jpg)
Types of telescopes
For each energy range, we’ll discuss:
Single telescopes
InterferometersMore than one telescope linked together
![Page 43: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/43.jpg)
Types of EM radiation
Low frequency/long wavelength LOW ENERGY
Radio
Millimeter
Sub-millimeter
Mid frequency/mid wavelength MID ENERGY
Infrared
Optical
High frequency/short wavelength HIGH ENERGY
Ultraviolet
X-ray
Gamma ray
![Page 44: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/44.jpg)
Radio, millimeter, and submillimeter astronomyThe place of radio, millimeter, and submillimeter
astronomy the study of astronomy
The parts of a radio telescope and how it works
The two big challenges of radio astronomy overcome by radio astronomers
Tiny signal strength of radio signals
Low angular resolution
Next generation radio, millimeter, and submillimeter telescopes
![Page 45: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/45.jpg)
Low energy EM radiation
frequency wavelength
Radio
100MHz - 100GHz
3m-3mm
Millimeter
100GHz-300GHz
3mm-1mm
Submillimeter
300GHz-1000GHz
1mm-0.3mm
![Page 46: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/46.jpg)
Discovery of CMB
Arno Penzias and Robert Wilson (1965)
![Page 47: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/47.jpg)
Discovery of pulsars
Jocelyn Bell and 81.5 MHz radio telescope (1967)
![Page 48: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/48.jpg)
Sources of radio, millimeter, and sub-millimeter radiation
HII regions
Synchrotron radiation
Interstellar atoms and molecules
Pulsars, quasars, radio galaxies
Cosmic microwave background
![Page 49: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/49.jpg)
Carl Jansky’s telescopeJansky's vertically polarized beam antenna was built in 1931 to study the direction of thunderstorms, which were suspected to cause signal-to-noise problems in Bell Lab’s initial transoceanic radio-telephone circuits.
In addition to detecting lightning, Jansky detected a signal that that appeared 4 minutes earlier each day and was strongest when Sagittarius was high in the sky.
The center of the Galaxy is in the direction of Sagittarius, so Jansky concluded that he was detecting radio waves from an astronomical source
![Page 50: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/50.jpg)
Grote Reber’s telescope
Grote Reber read about Jansky's discovery.
In 1937, Reber built his own 32-foot-diameter parabolic dish antenna in his backyard in Wheaton, Illinois to seek cosmic radio emissions.
![Page 51: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/51.jpg)
Grote Reber’s telescope
In the spring of 1939, he was able to detect cosmic radio emissions with his equipment. In 1941, he made the first survey of the sky at radio wavelengths (160MHz).
![Page 52: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/52.jpg)
Reber’s telescope
On display at Greenbank Radio ObservatoryGreenbank, WV
![Page 53: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/53.jpg)
Radio, millimeter, and submillimeter astronomyThe place of radio, millimeter, and submillimeter
astronomy the study of astronomy
The parts of a radio telescope and how it works
The two big challenges of radio astronomy overcome by radio astronomers
Tiny signal strength of radio signals
Low angular resolution
Next generation radio, millimeter, and submillimeter telescopes
![Page 54: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/54.jpg)
Parts of a radio telescope
AntennaCollects the radiation
Focuses the radiation on the receiver horn
ReceiverHorn
Amplifies the signal
Converts the radio-frequency signal to signals (current/voltage) we can record and analyze
Steering gear
Moves the telescope as it tracks the observed object
![Page 55: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/55.jpg)
Parts of a radio telescope
Antenna
Receiver
Antenna
Receiver
Steering gear
Parkes 64-meter radio telescope
![Page 56: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/56.jpg)
Film clip of Parkes Radio Telescopefrom
“The Dish”
![Page 57: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/57.jpg)
Parts of a radio telescope
Receivers
Primary antennaSecondaryreflector
Hat Creek Radio Observatory
Steering gear
![Page 58: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/58.jpg)
Parts of a radio telescope
Antenna
Collects the radiation
Focuses the radiation on the receiver horn
Receiver
Horn
Amplifies the signal
Converts the radio-frequency signal to signals (current/voltage) we can record and analyze
Steering gear
Moves the telescope as it tracks the observed object
![Page 59: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/59.jpg)
Antenna surface errors
The surface error (accuracy of antenna surface and shape) should be less than 1/20 wavelength to keep losses to less than 30%
This results in much more stringent requirements for
sub-millimeter telescopes than for radio telescopes.
![Page 60: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/60.jpg)
Antenna surface errors
1/20=0.05mmMillimeter
1/20=0.015mmSub-millimeter
Smoother
Smooth Smoothest
NRAO 12 meter (1mm-3mm)
Kitt Peak
JCMT (0.3mm-2.0mm)Mauna Kea
1/20=0.15mmRadioVLBA (3mm-3m)
Mauna Kea
![Page 61: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/61.jpg)
Antenna surface errors
This image was taken during the SMT reflector's holographic testing showing that the deviations of the reflector are nearing the targeted 0.015 microns (about the thickness of a human hair)
![Page 62: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/62.jpg)
Parts of a radio telescope
Antenna
Collects the radiation
Focuses the radiation on the receiver horn
Receiver
Horn
Amplifies the signal
Converts the radio-frequency signal to signals (current/voltage) we can record and analyze
Steering gear
Moves the telescope as it tracks the observed object
![Page 63: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/63.jpg)
ReceiversHorn
Purpose of the horn is to collect the radiation directed to it from the antenna.
Amplifier
Increases the amplitude of the signal
Mixer
Used to change the frequency to a more easily used frequency
![Page 64: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/64.jpg)
Receivers
Store data
Radio Amplifiermixer (mix to baseband freq) Convert to
desired form to record/analyze
Store data
Millimeter Convert to
desired form to record/analyze
Submillimeter
Store dataConvert to
desired form to record/analyze
Mixer (mix to lower freq)
Horn
![Page 65: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/65.jpg)
Reasons to use a mixer
Amplifiers don’t work at very high frequencies, so must change to a lower frequency before amplifying
Want all of the electronics that change the signal to forms we can record and analyze to only have to be designed for one frequency (called baseband frequency).
If the signal must be transmitted a long distance, there will be less loss if the frequency is first shifted to a lower frequency
![Page 66: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/66.jpg)
Receivers
The design of the receiver is effected greatly by whether the radiation observed is radio, millimeter, or submillimeter.
![Page 67: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/67.jpg)
Receivers
The size of the electronics gets smaller as the wavelength gets shorter (higher frequencies)
So devices associated with radio telescope receivers
(long wavelength) are larger than the devices associated with millimeter and submillimeter receivers (shorter wavelengths).
![Page 68: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/68.jpg)
Radio receivers
Radio
100MHz - 100GHz
3m-3mm
![Page 69: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/69.jpg)
Radio receivers
Arecibo Observatory
receivers
![Page 70: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/70.jpg)
Arecibo radio telescope
Receivers are inside the dome
![Page 71: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/71.jpg)
Radio receivers
receivers
![Page 72: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/72.jpg)
Radio receivers
![Page 73: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/73.jpg)
Radio receivers
VLBA telescope
receivers
![Page 74: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/74.jpg)
Radio receivers
VLBA telescope
![Page 75: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/75.jpg)
Radio horns
VLBA telescope
~1 meter
![Page 76: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/76.jpg)
Millimeter receivers
Millimeter
100GHz-300GHz
3mm-1mm
![Page 77: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/77.jpg)
Millimeter wave receiver
ReceiversHat Creek Radio Observatory
![Page 78: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/78.jpg)
Millimeter wave receiver
![Page 79: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/79.jpg)
Millimeter wave receiverHorns
Amplifiers~0.5 m
![Page 80: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/80.jpg)
Millimeter wave horns
~2cm
![Page 81: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/81.jpg)
Millimeter wave receiver electronics
Intermediate frequency (IF) plate
![Page 82: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/82.jpg)
Millimeter wave electronics
Local oscillator
![Page 83: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/83.jpg)
Submillimeter receivers
Submillimeter
300GHz-1000GHz
1mm-0.3mm
![Page 84: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/84.jpg)
Submillimeter receiver
230 GHz mixer block CSO, Mauna Kea
![Page 85: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/85.jpg)
Submillimeter receiver
CSO, Mauna Kea
![Page 86: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/86.jpg)
Submillimeter receivers
All of the receivers shown are called COHERENT detectors.
COHERENT detectors preserve the phase information and spectral information is retained.
Another type of receiver is called INCOHERENT detector.
INCOHERENT detectors respond only to the total power of the signal.
![Page 87: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/87.jpg)
Submillimeter receivers
A type of INCOHERENT detector is called a bolometer.
A bolometer is a device that changes its electrical resistivity in response to heating by illuminating radiation.
Bolometers may be made of cooled semiconductors coated with an appropriate absorber for the wavelength which is to be observed.
![Page 88: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/88.jpg)
Submillimeter receivers
SCUBA The Submillimeter Common-User Bolometer
Array
JCMT, Mauna Kea
![Page 89: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/89.jpg)
Submillimeter receivers
SCUBA The Submillimeter Common-User Bolometer
Array
JCMT, Mauna Kea
![Page 90: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/90.jpg)
Parts of a radio telescope
Antenna
Collects the radiation
Focuses the radiation on the receiver horn
Receiver
Horn
Amplifies the signal
Converts the radio-frequency signal to signals (current/voltage) we can record and analyze
Steering gear
Moves the telescope as it tracks the observed object
![Page 91: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/91.jpg)
Steering gear
There are 2 styles of steering gear:
Altitude-azimuth mount
Equatorial mount
![Page 92: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/92.jpg)
Altitude azimuth mount
Antenna
Receiver
Altitude track
Azimuth axisVLA Very Large Array
![Page 93: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/93.jpg)
Equatorial mount
Antenna
Receiver
Polar axis
Polaris
Declination track
Right ascension track
Green Bank 140 ft
![Page 94: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/94.jpg)
Radio, millimeter, and submillimeter astronomy
The place of radio, millimeter, and submillimeter astronomy the study of astronomy
The parts of a radio telescope and how it works
The two big challenges of radio astronomy overcome by radio astronomers
Tiny signal strength of radio signals
Low angular resolution
Next generation radio, millimeter, and submillimeter telescopes
![Page 95: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/95.jpg)
Cosmic radio signals are very weak!
All the energy collected by all the radio telescopes on Earth during the >60 year history of radio astronomy amounts to no more than the energy released when a few raindrops hit the ground!
![Page 96: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/96.jpg)
Cosmic radio signals are very weak!
This places strict requirements on the design of a radio telescope!
![Page 97: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/97.jpg)
Design to overcome small signal strength
Antenna
LARGE COLLECTING AREA
Receiver
LOW NOISE
![Page 98: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/98.jpg)
Design to overcome small signal strength
Antenna
LARGE COLLECTING AREA
Receiver
LOW NOISE
![Page 99: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/99.jpg)
Large collecting area
Parkes 64-meter radio telescope
![Page 100: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/100.jpg)
Larger collecting area
100-meter GBT Green Bank Telescope (Great Big Telescope)
![Page 101: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/101.jpg)
Largest collecting area
300 meter radio telescope, Arecibo Observatory
![Page 102: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/102.jpg)
Largest dish (but not fully steerable)
300 meter radio telescope at Arecibo Observatory
![Page 103: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/103.jpg)
Arecibo radio telescope
Since Arecibo’s dish is not moveable, tracking is accomplished by moving the receivers instead.
Receivers are inside the dome
Receiver
![Page 104: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/104.jpg)
Arecibo radio telescope
Altitude track
Azimuth track
![Page 105: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/105.jpg)
Requirements of a radio telescope
Antenna
LARGE COLLECTING AREA
Receiver
LOW NOISE
![Page 106: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/106.jpg)
Cryogenics
One way to lower noise is to operate all the electronics at low temperatures.
This lowers the thermal noise resulting in a higher signal to noise S/N ratio.
![Page 107: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/107.jpg)
Cryogenics
The desired cooling to less than 20K is accomplished with high pressure helium gas.
Most telescopes are equipped with helium compressors.
The electronics are operated in a cryostat (thermos) containing high pressure helium gas.
![Page 108: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/108.jpg)
Receiver/cryostat
Helium pump
Cryostat
![Page 109: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/109.jpg)
Cryogenics
Helium manifold
Helium from compressor
![Page 110: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/110.jpg)
Radio, millimeter, and submillimeter astronomy
The place of radio, millimeter, and submillimeter astronomy the study of astronomy
The parts of a radio telescope and how it works
The two big challenges of radio astronomy overcome by radio astronomers
Tiny signal strength of radio signals
Low angular resolution
Next generation radio, millimeter, and submillimeter telescopes
![Page 111: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/111.jpg)
What is resolution?
High resolutionLow resolution
Andromeda galaxy
![Page 112: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/112.jpg)
What is resolution?
The resolution of a telescope is expressed as an angle.
![Page 113: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/113.jpg)
What is resolution?
10 arc sec 5 arc sec
Greatly magnified views
![Page 114: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/114.jpg)
What is resolution?
The resolution of a telescope is equal to:
wavelength telescope diameter
Since radio waves have longer wavelengthsthan all other forms of EM waves,the resolution of radio images in inherentlylower.
![Page 115: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/115.jpg)
What is resolution?
The resolution of a telescope is equal to:
wavelengthtelescope diameter
One way to increase the resolution is to increase the diameter of the telescope.
![Page 116: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/116.jpg)
What is resolution?
Arecibo Observatory
300 meters
This is about the biggest diameter that is practical to build
![Page 117: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/117.jpg)
What is resolution?
The resolution of an interferometer is equal to:
wavelengthbaseline
Another way to increase the resolution is to build an interferometer.
![Page 118: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/118.jpg)
Radio interferometer
baseline
VLA
![Page 119: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/119.jpg)
Film clip of the Very Large Array (VLA)from
“Contact”
![Page 120: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/120.jpg)
Interference
![Page 121: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/121.jpg)
Sea interferometer
The "Sea Interferometer", was formed by combining Yagi arrays with the surface of the sea near Syndey, Australia.
The antenna could observe both direct radiation from the sun and those reflected from the surface of the sea. The direct and reflected waves interfered with each other producing the characteristic fringe pattern of an interferometer with a baseline roughly twice that of the cliff.
1947 First radio interferometric observations by McCready (Sydney, Australia)
![Page 122: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/122.jpg)
Resolution of an interferometer
Field of view = Wavelength / dish diameter
Resolution = Wavelength / baseline
![Page 123: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/123.jpg)
Resolution of an interferometer
30arc sec
10 arc sec
30arc sec
5 arc sec
Greatly magnified views
Longer baseline
![Page 124: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/124.jpg)
Resolution of an interferometer
BIMA observations of the emission from HCN and C4H in IRC+10216. The synthesized beamsizes are shown in the lower
right of each panel.
![Page 125: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/125.jpg)
Aperture synthesis
Another name for interferometry is aperture synthesis.
One is trying to synthesize the aperture of a large single dish with several smaller dishes.
![Page 126: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/126.jpg)
Aperture synthesis
Advantage
Increased resolution
Disadvantage
Less sensitivity
![Page 127: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/127.jpg)
Aperture synthesis
baseline
VLA
![Page 128: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/128.jpg)
Some examples of interferometers
![Page 129: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/129.jpg)
Radio interferometer
baseline
Very Large Array (VLA),NM
27 25-meter telescopes
![Page 130: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/130.jpg)
Radio interferometer
baseline
RYLE telescope
England
8 14-meter telescopes
![Page 131: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/131.jpg)
Radio interferometer
baseline
Westerbork Synthesis Radio Telescope
(WSRT)
Netherlands
14 25-meter telescopes
![Page 132: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/132.jpg)
VLBA Very Long Baseline Array
10 telescopes from Hawaii to St. Croix
![Page 133: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/133.jpg)
Millimeter interferometer
baseline
Hat Creek Radio Observatory CA 10 elements, 6-meter telescopes
![Page 134: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/134.jpg)
Millimeter interferometer
baseline
Owen’s Valley Radio Observatory (OVRO), CA 6 10.4-meter telescopes
![Page 135: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/135.jpg)
Millimeter interferometer
baseline
Nobeyama Millimeter Array
(NMA)
Japan
6 10-meter telescopes
![Page 136: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/136.jpg)
Submillimeter interferometer
baseline
CSO/JCMT Interferometer, Mauna KeaFirst astronomical interferometer to operate at submillimeter frequencies
151.91m baseline, 1.1” resolution at 345GHz
![Page 137: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/137.jpg)
Aperture synthesis
What is the longest baseline achieved?.
![Page 138: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/138.jpg)
Aperture synthesis
.
HALCA, Highly Advanced Laboratory for Communications and Astronomy.
In Japanese, HALCA means `far away’
8-meter radio telescope in elliptical earth orbit
21,000 km at apogee
Provides baselines 3 times longerthan earth-based observations(earth’s radius = 6378 km)
1.6GHz, 5GHz, 22GHz
baseline
![Page 139: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/139.jpg)
Aperture synthesis
.
Resolution = 2cm/24,000km
Resolution = 0.002”
baseline
HALCA
![Page 140: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/140.jpg)
Space VLBI
Ground-based telescopes only
HALCA with 10 earth-based
telescopes
The strongest radio signals are produced near the center of a quasar where astronomers believe that hot gas and stars are interacting with a super-massive black hole.
The material which is being blown out from the quasar can be seen more clearly in the HALCA image.
![Page 141: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/141.jpg)
Radio, millimeter, and submillimeter astronomy
The place of radio, millimeter, and submillimeter astronomy the study of astronomy
The parts of a radio telescope and how it works
The two big challenges of radio astronomy overcome by radio astronomers
Tiny signal strength of radio signals
Low angular resolution
Next generation radio, millimeter, and submillimeter telescopes
![Page 142: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/142.jpg)
ALMAAtacama Large Millimeter Array
Increase current sensitivity of millimeter/submillimeter telescopes by 40 times.
Sixty-four 12-meter diameter antennas
![Page 143: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/143.jpg)
SKA Square Kilometer Array
To see galaxies during the earliest epochs of their formation requires at least 20 times more collecting than is provided by the largest radio telescope in operation today.
Such sensitivity would be provided by a radio telescope that has a collecting area one square kilometer.
![Page 144: Telescopes Donna Kubik PHYS162 Spring, 2006. Purpose of telescopes To do what our eyes cannot Collect photons (from radio to gamma ray) Achieve higher](https://reader035.vdocuments.us/reader035/viewer/2022062714/56649d045503460f949d76fe/html5/thumbnails/144.jpg)
Next lecture
Low frequency/long wavelength LOW ENERGY
Radio
Millimeter
Sub-millimeter
Mid frequency/mid wavelength MID ENERGY
Infrared
Optical
High frequency/short wavelength HIGH ENERGY
Ultraviolet
X-ray
Gamma ray