Download The Moon - Highland High School

CH
The Sun-Earth-Moon System
Section 27.1: Tools of Astronomy
Section 27.2: The Moon
Section 27.3: The Sun-Earth-Moon System
Section 27.1
Tools of Astronomy
Objectives
Define electromagnetic radiation.
Explain how telescopes work.
Describe how space exploration helps scientists
learn about the universe.
Section 27.1
Tools of Astronomy
Radiation emitted or reflected by distant
objects allows scientists to study the universe.
Review Vocabulary
refraction: occurs when a light ray
changes direction as it passes from one
material into another
Section 27.1
Tools of Astronomy
New Vocabulary
electromagnetic
spectrum
refracting telescope
reflecting telescope
interferometry
Section 27.1
Tools of Astronomy
Radiation
The radiation from bodies throughout the
universe that scientists study is called
electromagnetic radiation.
This includes visible light, infrared and
ultraviolet radiation, radio waves,
microwaves, X rays, and gamma rays.
Section 27.1
Tools of Astronomy
Radiation
The electromagnetic spectrum
consists of all types of electromagnetic
radiation arranged according to
wavelength and frequency.
Section 27.1
Tools of Astronomy
Radiation
Wavelength and frequency
Electromagnetic radiation is classified by
wavelength, the distance between peaks
on a wave, and frequency, the number of
waves or oscillations that pass a given
point per second.
Section 27.1
Tools of Astronomy
Radiation
Wavelength and frequency
Frequency is related to wavelength by the
mathematical relationship c = λf, where c
is the speed of light (3.0 × 108 m/s), λ is
the wavelength, and f is the frequency.
Section 27.1
Tools of Astronomy
Telescopes
Telescopes provide the ability to observe
wavelengths beyond what the human eye
can detect. They collect electromagnetic
radiation from distant objects and focus it so
that an image of the object can be recorded.
Telescopes can also collect light over periods
of minutes or hours.
Section 27.1
Tools of Astronomy
Telescopes
Refracting and reflecting telescopes
Refracting telescopes
use lenses to focus
visible light.
Section 27.1
Tools of Astronomy
Telescopes
Refracting and reflecting telescopes
Reflecting telescopes
use mirrors to focus
visible light.
Section 27.1
Tools of Astronomy
Telescopes
Telescopes using non-visible wavelengths
For all telescopes, the goal is to bring as
much electromagnetic radiation as possible
into focus.
Infrared and ultraviolet radiation can be
focused by mirrors in a way similar to that
used for visible light.
Section 27.1
Tools of Astronomy
Telescopes
Telescopes using non-visible wavelengths
X rays cannot be focused by normal mirrors,
and thus special designs must be used.
Gamma rays cannot be focused, so
telescopes designed to detect this type of
radiation can determine only the direction
from which the rays come.
Section 27.1
Tools of Astronomy
Telescopes
Telescopes using non-visible wavelengths
A radio telescope collects the longer
wavelengths of radio waves with a large
dish antenna and reflects them to a point
above the dish. There, a receiver converts
the radio waves into electric signals that
can be stored in a computer for analysis.
Section 27.1
Tools of Astronomy
Telescopes
Telescopes using non-visible wavelengths
The data collected from radio telescopes are
converted into visual images by a computer.
The image resolution can be improved using
interferometry, a process that links separate
telescopes so they act as one telescope,
producing more detailed images as the
distance between the telescopes increases.
Section 27.1
Tools of Astronomy
Space-Based Astronomy
Space-based telescopes allow astronomers
to study radiation that would be blurred by
our atmosphere.
Section 27.1
Tools of Astronomy
Space-Based Astronomy
Hubble Space Telescope
The Hubble Space Telescope was
designed to obtain sharp visible-light
images without atmospheric interference
and to make observations in infrared and
ultraviolet wavelengths.
Section 27.1
Tools of Astronomy
Please click the image above to view the interactive table.
Section 27.1
Tools of Astronomy
Space-Based Astronomy
Spacecraft
Spacecraft make observations from above
Earth’s atmosphere and can also be sent
directly to the bodies being observed.
Robotic probes are spacecraft that can
make close-up observations and sometimes
land to collect information directly.
Section 27.1
Tools of Astronomy
Space-Based Astronomy
Human spaceflight
The space shuttle provides an environment
for scientists to study the effects of
weightlessness on humans, plants, the
growth of crystals, and other phenomena.
Because shuttle missions last a maximum of
just 17 days, long-term effects must be
studied in space stations.
Section 27.1
Tools of Astronomy
Space-Based Astronomy
Spinoff technology
Many technologies that were originally
developed for use in space programs are
now used by people around the world. More
than 1400 different NASA technologies, such
as cordless tools, have been passed on to
commercial industries for common use; these
are called spinoffs.
Section 27.2
The Moon
Objectives
Describe the history of lunar exploration.
Recognize lunar properties and structures.
Identify features of the Moon.
Explain the theory of how the Moon formed.
Section 27.2
The Moon
The Moon, Earth’s nearest neighbor in
space, is unique among the moons in our
solar system.
Review Vocabulary
lava: magma that flows onto the surface
from the interior of an astronomical body
Section 27.2
The Moon
New Vocabulary
albedo
ejecta
highland
ray
maria
rille
impact crater
regolith
Section 27.2
The Moon
Exploring the Moon
Most knowledge of the Moon comes from
explorations by space probes and from
landings by astronauts.
Section 27.2
The Moon
Exploring the Moon
The first step toward reaching the Moon was
in 1957, when the Soviet Union launched
the first artificial satellite, Sputnik I.
Four years later, Soviet cosmonaut Yuri A.
Gagarin became the first human in space.
Section 27.2
The Moon
Exploring the Moon
In 1957, the United States launched the first
American, Alan B. Shepard, Jr., into space
during Project Mercury.
This was followed by Project Gemini that
launched two-person crews.
Section 27.2
The Moon
Exploring the Moon
On July 20, 1969, the Apollo program landed
Neil Armstrong and Edwin “Buzz” Aldrin on
the Moon during the Apollo 11 mission.
After a gap of many years, scientists hope to
return to the Moon before 2029.
Section 27.2
The Moon
The Lunar Surface
The albedo of the Moon, the percentage of
incoming sunlight that its surface reflects, is
very small—only about 7 percent.
In contrast, Earth has an average albedo of
nearly 31 percent.
Section 27.2
The Moon
The Lunar Surface
Lunar highlands are heavily cratered
regions of the Moon that are light in
color and mountainous.
Maria are dark, smooth plains, which
average 3 km lower in elevation and
have few craters.
Section 27.2
The Moon
The Lunar Surface
Lunar craters
The craters on the Moon, called impact
craters, formed when objects from space
crashed into the lunar surface.
The material blasted out during these
impacts fell back to the Moon’s surface as
ejecta.
Section 27.2
The Moon
The Lunar Surface
Lunar craters
Some craters have long trails of ejecta,
called rays, that radiate outward from the
impact site.
Rilles are meandering, valleylike structures
that might be collapsed lava tubes.
Section 27.2
The Moon
The Lunar Surface
Lunar properties
Earth’s moon is unique among all the moons
in the solar system.
1.It is one of the largest moons compared to
the radius and mass of the planet it orbits.
2. It is a solid, rocky body, in contrast with the
icy compositions of other moons of the solar
system.
Section 27.2
The Moon
The Lunar Surface
Lunar properties
3.The Moon’s orbit is farther from Earth
relative to the distance of most moons
from the planets they orbit.
4. Moon’s albedo is 7%. Earth’s 31%.
Section 27.2
The Moon
The Lunar Surface
Lunar properties
5.The Moon is made up of minerals similar
to those of Earth—mostly silicates.
The highlands are mostly lunar breccias,
which are rocks formed by the fusion of
smaller rocks during impacts. The maria are
predominantly basalt that contains no water.
Section 27.2
The Moon
Please click the image above to view the interactive table.
Section 27.2
The Moon
History of the Moon
The Moon is approximately 3.8 to 4.6 billion
years old, about the same age as Earth.
Scientists theorize that the Moon was heavily
bombarded during its first 800 million years.
This caused the breaking and heating of
surface rocks and resulted in a layer of loose,
ground-up rock called regolith on the surface.
Section 27.2
The Moon
History of the Moon
Layered structure
Scientists infer from
seismic data that the
Moon, like Earth, has a
layered structure, which
consists of the crust,
upper mantle, lower
mantle, and core.
Section 27.2
The Moon
History of the Moon
Formation of maria
After the period of intense bombardment
that formed the highlands, lava welled
up from the Moon’s interior and filled in
the large impact basins.
This lava fill created the dark, smooth
plains of the maria.
Section 27.2
The Moon
History of the Moon
Tectonics
Scientists think that the Moon is not
tectonically active because the Moon has
no active volcanoes and no significant
magnetic field.
Section 27.2
The Moon
Formation
The Moon probably formed as the result of a
collision between Earth and a Mars-sized
object about 4.5 bya when the solar system
was forming.
Section 27.2
The Moon
Formation
The impact theory of the Moon’s formation
states that material ejected from Earth and
from the striking object eventually merged to
form the Moon.
CH
Study Guide
Key Concepts
Section 27.1 Tools of
Astronomy
Radiation emitted or reflected
by distant objects allows scientists to study
the universe.
 Telescopes collect and focus
electromagnetic radiation emitted or
reflected from distant objects.
 Electromagnetic radiation is classified by
wavelength and frequency.
CH
Study Guide
Key Concepts
Section 27.1 Tools of
Astronomy
 The two main types of optical telescopes are
refractors and reflectors.
 Space-based astronomy includes the study
of orbiting telescopes, satellites, and probes.
 Technology originally developed to explore
space is now used by people on Earth.
CH
Study Guide
Key Concepts
Section 27.2 The Moon
The Moon, Earth’s nearest
neighbor in space, is unique among the
moons in our solar system.
 Astronomers have gathered information
about the Moon using telescopes, space
probes, and astronaut exploration.
 Like Earth’s crust, the Moon’s crust is
composed mostly of silicates.
CH
Study Guide
Key Concepts
Section 27.2 The Moon
 Surface features on the Moon include
highlands, maria, ejecta, rays, and rilles.
It is heavily cratered.
 The Moon probably formed about 4.5 bya
in a collision between Earth and a Marssize object.
CH
The Sun-Earth-Moon System
27.1 Section Questions
Gamma rays move through space at a greater
speed than do radio waves.
a. true
b. false
CH
The Sun-Earth-Moon System
27.1 Section Questions
Which objects produce the image in a
refracting telescope?
a. mirrors
b. lamps
c. lenses
d. prisms
CH
The Sun-Earth-Moon System
27.1 Section Questions
What advantage do telescopes in space have
over similar instruments on Earth’s surface?
a. The telescopes are closer to the object.
b. The telescopes are above the atmosphere.
c. The telescopes are safe from damage.
d. The telescopes are always in the dark.
CH
The Sun-Earth-Moon System
27.2 Section Questions
The Moon has a lower density than that of Earth.
a. true
b. false
CH
The Sun-Earth-Moon System
27.2 Section Questions
Which term refers to valleylike structures on the
Moon that might be lava tubes?
a. ejecta
b. rays
c. rilles
d. highlands
CH
The Sun-Earth-Moon System
27.2 Section Questions
Which theory about how the Moon formed
is most accepted?
a. The Moon was captured by Earth.
b. The Moon condensed with Earth.
c. A Mars-sized object struck Earth.
d. A piece broke off of Earth.