Chapter 28 – Sun-Earth-Moon System

Space, the final frontier...

-Cpt. James T. Kirk-

USS Enterprise

28.1 Tools of Astronomy

OBJECTIVES

Describe electromagnetic radiation.Explain how telescopes work.Describe space exploration.

28.1 Electromagnetic spectrum

The arrangement of waves that includes gamma rays, X rays, ultraviolet radiation, visible light, infrared radiation, microwaves, and radio waves according to wavelength and frequency is called the electromagnetic spectrum.

28.1 Refracting Telescopes

The telescope that uses lenses to bring visible light to a focus is a refracting telescope.

28.1 Reflecting Telescopes

Telescopes that uses mirrors to bring visible light to a focus

28.1 Interferometry

Interferometry is the process of linking many separate telescopes together to act as one

28.1 Satellites

Telescopes are placed above the atmosphere in order to most effectively collect infrared and ultraviolet radiation, X-rays, and gamma rays.

Hubble Space Telescope

28.1 Mars Probe (unpublished)

28.1 Space spinoff

Cell phones, PCs, flat screen TV are a few examples of this.

28.2 The Moon

OBJECTIVES

Describe the development of exploration of the Moon

Identify features on the Moon.

Explain the theories about how Moon was created.

Space Race

Yuri Gagarin was the first man in space.

Project Mercury

Alan Shepard was the first American man in space.

Project Mercury launched the first American into space on May 5, 1960.

Project Gemini

Project Gemini launched a two-person spacecraft into orbit in 1965.

Project ApolloThe space exploration program

that landed astronauts on the Moon was Apollo.

Apollo Missions

July 20, 1969Neil Armstrong was the first

man to step foot on the Moon.

Moon’s Features

The Moon’s surface is very different from the surface of Earth because the Moon has no erosion.

Ejecta

Ejecta is the material blasted out of the Moon’s surface as a result of space-object impacts.

Mare

Dark, smooth plains on the Moon's surface (Maria, pl.)

Albedo

The portion of sunlight reflected by the Moon’s surface.

(actually from any satellite or planet that cannot produce its own light)

Rilles

Valley-like structures on the Moon's surface

Synchronous Rotation

The Moon's state, in which its rotational and orbital periods are equal

Simultaneous formation

theory

The theory that suggests the Moon was formed at about the same time as Earth and from similar materials is called the simultaneous formation theory.

Moon Tracks – Features & HistoryWeb-site:

http://trackstar.4teachers.org/trackstar/Find A Track – View Track # 317121

28.2 Moon Tracks

28.3 The Sun-Earth-Moon System

OBJECTIVES

Identify the relative positions and motions of Earth, the Sun , and the Moon.

Describe the phases of the moon.Explain eclipses of the Sun and Moon.

Earth’s Rotation

The daily rising and setting of heavenly objects like the Sun is caused by the rotation of Earth.

Solar Day

Our timekeeping system is based on the solar day.

Foucault pendulumHanging-weight system that helps demonstrate the rotation of

Earth

Ecliptic

Plane of the Earth's orbit about the Sun called the ecliptic

Earth’s Tilt

Different seasons occur because of Earth’s tilt and Earth’s orbital motion around the Sun.

Solstice

Earth’s position near or on December 21, at which the northern hemisphere has its minimum daylight hours

Earth’s position around June 21, at which the northern hemisphere has its maximum daylight hours

Equinox

Earth’s position when the lengths of day and night are equal

‘Vernal’

‘Autumnal’

Earth-Sun Relations

Apogee vs. perigee

Apogee - Farthest point from Earth in the Moon’s orbit

Perigee - Closest point to Earth in the Moon’s orbit

Lunar Phases

The sequential changes in the appearance of the Moon are called lunar phases.

Sun

Waxing

When the Moon waxes during its lunar cycle, the amount of its sunlight portion that we see appears to increase in size.

“Blue Moon”

When 2 full moons occur in the same calendar month..

Year MonthFirst Full Moon

Blue Moon

2009 December 2nd at 07:29 31st at 19:11

Year MonthFirst Full Moon

Blue Moon

2012 August 2nd at 03:25 31st at 13:56

Lunar Eclipse

A lunar eclipse occurs when the Moon passes through Earth's shadow.

Can only occur during the phase of the full moon.

Solar Eclipse

Occurs when the Moon passes directly between the Sun and Earth (Solar eclipses can only occur at time of New Moon)

Partial Eclipse

People who see a partial solar eclipse are located in the penumbra portion of the Moon's shadow.

Eclipses - Why not every month?

The orbit of the Moon is tilted 5° relative to the ecliptic plane of the Earth-Sun. ie. Most months its shadow passes north or south of the Earth.

Coming Eclipses (2001-2005)

A lunar eclipse occurs when the Earth passes directly between the Sun and the Moon and blocks some or all of the light of the Full Moon.

(Lunar eclipes can only occur at time of Full Moon)