Transcript NS2-M3C12S2_-_The_Radiotelescopex

Module 3 – Nautical Science
Unit 4 – Astronomy
Chapter 12 - Astronomical Observations
Section 2 – The Radiotelescope
What You Will Learn to Do
Demonstrate an understanding of
astronomy and how it pertains to our solar
system and its related bodies: Moon, Sun,
stars and planets
Objectives
1. Explain the discovery and development
of the radiotelescope
2. Explain the special uses of the
radiotelescope and give its purpose
3. Identify the methods for using balloon
observatories
Key Terms
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
Opening Question
What is a
radiotelescope
and how is it
different from
an ordinary
telescope?
(Use CPS “Pick a Student” for this question.)
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
radiotelescop
e has a
diameter
of 1,000 feet.
Arecibo, Puerto Rico
The Radiotelescope
Radiotelescope photography of Jupiter
Jupiter: radio
(21 cm)
Jupiter: visible
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.
Check On Learning Questions
CPS Lesson
Question
3-4
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
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.
Transmitter
Radiotelescope
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.
Check On Learning Questions
CPS Lesson
Question
5-6
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.
It rotates, carrying
the Sun and the
planets with it.
Globula
Clusters
Arms
Sun
Halo
Nucleus
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 spacebased platforms for
celestial observation.
Review Question
Discuss how
radiotelescopes
are used to
observe celestial
bodies.
(Use CPS “Pick a Student” for this question.)
Check On Learning Questions
CPS Lesson
Question
7-8
Questions?