Module 3 – Nautical Science Unit 4 – Astronomy Chapter 12 - Astronomical Observations Section 2 – The Radiotelescope

Demonstrate an understanding of astronomy and how it pertains to our solar system and its related bodies: Moon, Sun, stars and planets

Explain the discovery and development of the radiotelescope Explain the special uses of the radiotelescope and give its purpose Identify the methods for using balloon observatories

CPS Key Term Question 1

Key Terms Radiotelescope - A system consisting of an antenna, either parabolic or dipolar, used to gather radio waves emitted by celestial sources and bring them to a receiver placed in the focus

What is a radiotelescope and how is it different from an ordinary telescope?

The Radiotelescope Radiotelescope

The Radiotelescope Radiotelescopes must be very sensitive to detect faint radio waves from space. They are very large and do not require the precision of optical telescopes.

The Radiotelescope The world's largest steerable radiotelescope, the Robert Byrd at Green Bank, West Virginia, has a dish 328 feet in diameter.

The Radiotelescope Radiotelescope at Jodrell Bank in Cheshire, England Eifel Mountain near Bonn, Germany

The Radiotelescope The world’s largest stationary radiotelescope has a diameter of 1,000 feet. Arecibo, Puerto Rico

Radiotelescope photography of Jupiter The Radiotelescope Radiotelescope photography of Jupiter Jupiter: radio (21 cm) Jupiter: visible

National Radio Astronomy Observatory The Radiotelescope National Radio Astronomy Observatory in Socorro, New Mexico With this telescope’s array of 30 receivers, images of the radio sky can be produced to rival those of optical telescopes.

The Radiotelescope A star map is also called a radio source map. Some celestial bodies are too far away or too cold to radiate visible energy, and therefore do not correspond with an actual map of the stars.

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The Radiotelescope Sunspots and the corona of the Sun give off radiowaves.

The Radiotelescope A corona is a white or colored circle or set of concentric circles of light seen around a luminous body like the Sun.

The Radiotelescope Pulsars are rapidly rotating compressed stars in the last stages of stellar life. Pulsar Quasar

Composition of the Cosmos The Radiotelescope Composition of the Cosmos Spectroscopes and radioscopes have found that hydrogen and helium make up 99% of all matter in the universe. Heavy Elements: 0.03% Ghostly Neutrinos: 0.3% Stars: 0.5% Free Hydrogen and Helium: 4% Dark Matter: 30% (Hydrogen) Dark Energy: 65% (Hydrogen)

The Radiotelescope No matter where astronomers have searched in space, the universe appears to be made up of the same elements.

The Radiotelescope Radiotelescopes have also found molecules such as amino acids in space. No optical device could have accomplished this feat. Amino Acids

Special Uses of the Radiotelescope By equipping a radiotelescope with a transmitter, scientists are able to direct powerful radio beams at a celestial object and then receive them when they rebound toward Earth. Radiotelescope Transmitter Radiotelescopes equipped with such transmitters are often called radar telescopes.

Special Uses of the Radiotelescope Because radio waves travel at the speed of light, radar telescopes can furnish accurate data about the distance of celestial bodies near Earth.

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Special Uses of the Radiotelescope By using various wavelengths, information about the composition of these bodies can be obtained.

Special Uses of the Radiotelescope Radiotelescope technology has also showed that not all radio waves from space come from swirling, excited gases and celestial bodies. A particular kind of wave was found to be emitted by the cool, quiet hydrogen clouds strewn throughout space.

Special Uses of the Radiotelescope Mapping these hydrogen radio signals has enabled astronomers to see that our Milky Way galaxy is shaped like a pinwheel. Globula Clusters Arms Sun Halo Nucleus It rotates, carrying the Sun and the planets with it.

Special Uses of the Radiotelescope Radiotelescopes have also been used to control and receive data from spacecraft exploring our solar system.

Airborne Observations Balloon observatories can go 20 miles above the Earth's surface, eliminating 99 percent of the Atmosphere interference.

Airborne Observations Much of the distortion is eliminated when using a balloon observatory.

Airborne Observations Advantages to using Balloons: Cheaper than spacecraft Easily carries people aloft in gondolas Carries up to 2 tons of equipment and instruments Brings photos and findings directly back to Earth

Airborne Observations There are also a few disadvantages to using balloons: Difficulty in stabilization Observational distortions caused by the upper atmosphere Lack of self propulsion

Airborne Observations MIR Astrophysicists and astronomers in recent years have used space-based platforms for celestial observation.

Discuss how radiotelescopes are used to observe celestial bodies.

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