Topic 1 – History of the Skies:

Objects in the sky have fascinated humans throughout time. The explanations of how these celestial objects came to be are even more fascinating. Ancient civilizations developed their ideas of what was happening in the sky and explained it with their frame of reference. The constellations were patterns that seemed to tell stories about people.

Myths, folklore and legends were used to explain what ancient people observed in the night sky.First Nations people of the Pacific Northwest – believed the night sky was a pattern on a great blanket overhead, which was held up by a spinning ‘world pole’ resting on the chest of a woman named Stone Ribs. Aboriginal tribes – Algonquin, Iroquois and Narragansett believed the constellation Ursa Major was a bear running from hunters. Inuit in the high Arctic – used a mitt to determine when seal pups would be born, by holding the mitt at arm’s length at the horizon. Ancient Egyptians - The Sun God (Ra) was carried in a sacred boat across the sky every day.

Solstice represents the shortest and longest periods of daylight Winter solstice - shortest period of daylight (Northern hemisphere - Dec. 21) Summer solstice – longest period of daylight (Northern hemisphere - June 21)

Equinox represents periods of equal day and night Autumnal equinox – occurs in the fall (Northern hemisphere - Sept. 22)Vernal equinox – occurs in the spring (Northern hemisphere - Mar. 21)

Constellations are the groupings of stars we see as patterns in the night sky. There are 88 constellations and many are explained in Greek Mythology. Asterisms are also groupings of stars, but are not officially recognized as constellations.

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Sky Co-ordinates:

Altitude and Azimuth are calculated from the observer's position:

Altitude Azimuthtells you "how far above the horizon the object is"; the point straight overhead has an altitude of +90 degrees; straight underneath, an altitude of -90 degrees. Points on the horizon have 0 degree altitudes. An object halfway up in the sky has an altitude of 45 degrees.

determines "which compass direction it can be found in the sky." An azimuth of zero degrees puts the object in the North. An azimuth of 90 degrees puts the object in the East. An azimuth of 180 degrees puts the object in the South, and one of 270 degrees puts the object in the west.

measured with an astrolabe: measured with a compass:

Thus, if you are told that an object is at altitude 30 degrees, azimuth 80 degrees - look a little North of due East, about a third of the way from the horizon to the zenith.

Zenith is the position in the sky directly overhead.

Practice Questions:

1. You want to measure the co-ordinates of a celestial object. The first angle you measure is clockwise from north. What is the name for this angle? Next you measure the celestial objects angle above the horizon. What is this called?

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Models of the Solar System:

The Earth-Centered Model (Geocentric Model)

The Sun-Centered Model (Heliocentric Model)

The Earth was fixed and the center of the solar system with all celestial bodies in space rotating around it.

Nicholas Copernicus developed this model, in which the Sun was fixed and a rotating Earth revolved around it.

Aristotle’s Model - Assisted by Pythagoras and Euclid

Copernicus’ Model- Confirmed by Galileo and Kepler

Topic 2 – Telescopes:

Telescopes allow us to see objects that are very distant in space. In 1608, Hans Lippershey made one of the first telescopes – but it was Galileo Galilei who made practical use of it. The observations he made supported Copernicus’s Sun-Centered model (Heliocentric Model)

Optical telescopes are ‘light collectors’ that use lenses or mirrors to collect and focus the light from stars. There are two types of optical telescopes: Refracting and Reflecting.

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Refracting Telescope Reflecting TelescopeIt uses two lenses to gather and focus starlight. It uses mirrors instead of lenses to gather and

focus the light from the stars.

There is a limit to the size of lens that a refracting telescope can have. Diameters over 1 meter will cause the lens to warp.

An innovation for reflecting telescopes is the use of segmented mirrors (a segmented-mirror telescope uses several lightweight-segments to build one large mirror).

Copernicus’s Sun-Centered Revolution Continues:

Although Galileo’s observations helped to confirm the Sun-centered model of the universe, it was Johannes Kepler who performed the necessary calculations to determine the orbits of the planets. His calculations insisted that the orbits of the planets should be elliptical, instead of circular.

An ellipse is a figure that looks like a squashed circle.

Kepler mathematically worked out the orbit of Mars and found that it only worked if the orbit was elliptical. He also figured out the shape and scale of the entire known solar system.

Universal Gravitation:

Isaac Newton stated the law of universal gravitation eighty years after Kepler’s contribution about elliptical orbits of the planets. Newton’s law states that there is a gravitational force between all objects that pulls them together.

An orbit is the result of the attractive force of gravity balancing the straightforward movement of a planet because of velocity.

Practice Questions:

1. What are the two types of telescopes?

2. What shape are the orbits of the planets?

3. Describe how planets stay in stable orbits around the Sun.

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Topic 3 – Spectroscopy:

When a beam of light passes through a prism, it produces a spectrum of colors. Spectroscopy is the study of spectra (plural of

spectrum).

Different elements absorb and emit light differently because of their unique atomic structure. Each element has its own unique spectral lines. There are three different types of spectra: Continuous/Continuum, Emission and Absorption.

Astronomers refract (bend) the light from distant stars to determine what the star is made of. The spectra of the star are then compared to known spectra of elements to

determine the star’s composition. Every element absorbs and emits light differently. This means that each element has a spectra that is like a fingerprint: unique and useful for identification. 

Spectral Analysis of Stars: Scientists analyze spectra to determine the composition of a star. They look at the spectra of a star and compare the dark lines in the spectra to the dark lines in the spectra of different elements. The lines from the star spectrum result from the different elements that are present. Look at the example on the right. Starting from the left of the star spectrum, look at each dark line and find out which element it came from. In this star, the spectrum indicates the presence of iron and calcium, since all of the lines in the star spectrum line up with lines in one of those two spectra. In order for an element to be present, ALL lines would be seen in the star spectrum. 

The Doppler Effect & Red - Blue Shift: A change in the pitch (frequency) of sound waves because they are stretched or squeezed is known as the Doppler effect. Changes in the waves can be measured to determine how fast and in what direction a light-emitting object is moving. The position of the dark bands in a spectra shifts in the light waves of a moving

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star.

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Topic 4 - Exploring Space:

The Electromagnetic Spectrum:

Remember that visible light isn’t the only form of radiation coming from space. Radiation is a form of energy that does not require matter to travel. Light is a form of radiation, and its rays can have varying wavelengths and frequencies. The different types of electromagnetic radiation are outlined in the electromagnetic spectrum below.

We use a variety of instruments to observe many types of electromagnetic radiation in space.

Technology: Description: Example:

Optical Telescopes

Radio Telescopes

Space Telescopes

Satellites

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Space Probes

Space Stations

Practice Questions:

1. Create a Venn Diagram to compare/contrast:a. Optical Telescopes and Radio Telescopesb. Space Telescopes and Satellitesc. Space Probes and Space Stations

Triangulation:

We can use triangulation to estimate the distance to a star. If we take a known length of baseline, and measure the angle to a star on either end of that baseline, we can draw a scale diagram and use it to estimate the distance to the star.

Topic 5 – Space Debris:

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Satellites around Earth: - Earth has just one natural satellite orbiting it – the Moon!- Planet Earth has thousands of artificial satellites orbiting it.- The largest artificial satellite is the International Space Station- The smallest artificial satellites are debris – paint chips, fuel drops, bolts, spare parts and

other junk.

A geosynchronous orbit is an orbit that has the same orbital period as the rotation period of the Earth. The object in orbit will stay above the same location on the Earth

Space Debris Reflection:After reading and watching the resources in this topic (go online to the website!), articulate your thoughts and ideas on this important issue in written form (use full sentences and organize your thoughts into paragraphs). Use the guiding questions below to help you:1. What is space debris and why are people concerned?2. How big of a problem do you think this is?3. What do you think a potential solution to this problem might be?4. Is space travel worth all this pollution? Why or why not?

Topic 6 - Living in Space:

The Structure of the Universe:

Measurement in Space:

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The astronomical unit (AU) is used for measuring ‘local’ distances in the solar system. It is equal to the distance from the center of the Sun to the center of the Earth (approximately 149,599,000 kms). A light year is equal to the distance light travels in 1 year (approximately 9.5 trillion kms). It is used for longer distances – to stars and galaxies. The distance to our nearest star, Proxima Centauri is a little over 4 light years.

When you view an object in the sky you are seeing it as it was in the past. It has taken the light a very long time to reach the Earth. Light from the Sun takes about 5 minutes to reach the Earth, whereas light from Pluto takes about 5 hours. The farther away, the longer light takes to reach the Earth. Light from the stars in the center of the universe takes about 25,000 years to reach the Earth. The Hubble telescope is capturing light from 12 billion years ago.

The Sun: The Sun is made up of mostly hydrogen gas. It is 1.4 million km in diameter. Its temperature is about 15 million degrees Celsius. 600t of hydrogen are converted, by nuclear fusion, into helium per second. This is the energy released from the Sun. The Sun emits charged particles in all directions: this solar wind bombards the Earth at 400km/s, but the magnetic field of the Earth protects us.

Breaking Free of Earth’s Gravity: The energy it takes to get up into orbit and stay there is huge, since gravity must be overcome. To do this takes a speed of 8 km/s. This is called escape velocity, since 8 km/s (28,800 km/hr) is the velocity that is required to escape Earth's gravitational pull. 

The International Space Station - A Home In Space: Along with the United States, Russia, Europe and Japan, Canada is a partner in the International Space Station (ISS), an orbiting research laboratory. Since the first module of the Station was launched in 1998, the Station has circled the globe 16 times per day at 28,000 km/h at an altitude of about 370 km, covering a distance equivalent to the Moon and back daily. The Station is about as long as a Canadian football field, and has as much living space as a five-bedroom house.

Canada's contribution to the ISS is the Mobile Servicing System (MSS)—a sophisticated robotics suite that assembled the Station in space, module by module. Developed for the Canadian Space Agency by MDA of Brampton, Ontario, the MSS is comprised of:

Canadarm2, a 17-metre long robotic armDextre, the Station's two-armed robotic "handyman" andThe Mobile Base is a moveable work platform and storage facility.

Canada's investment gives Canadian scientists access to the ISS to conduct research for the benefit of Canadians.

Life in Space: Outside Earth’s atmosphere, life-support systems have to be artificially produced. Clean water, fresh air, comfortable temperatures and air pressure are essential to life. All these support systems, including a power supply to operate them, must be operational on the

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International Space Station at all times. Almost 100% of the water in the station must be recycled. Oxygen is produced by splitting water into its components, oxygen and hydrogen. The oxygen is used, and the hydrogen is vented into space. To survive in space, technologies have needed to be developed to overcome the hazards of this harsh environment. Space is a vacuum with no air or water. Cosmic and solar radiation, and meteoroids are the greatest dangers. Because there is no atmosphere, the temperatures in space have both extremes - from extremely hot to extremely cold. There is also no atmospheric pressure to help regulate the astronaut’s heartbeats. Long trips can present psychological difficulties, as can the claustrophobic feeling of such tight living conditions.

The Body and Microgravity:Living in microgravity (almost zero-gravity) can cause problems because of the effects of weightlessness on the human body.

- Bones have less pressure on them and so they expand. They also lose calcium and become more brittle.

- The heart doesn’t have to pump as hard to circulate blood. - Muscles weaken and shrink. - Depth perception is also affected.

Check Your Understanding:1. What does AU stand for and what is it?

2. How does the sun release energy?

3. What is the ISS? Who are the countries involved?

4. What is microgravity? Give three ways that microgravity can affect human bodies.

Topic 7 – Our Solar System

Our understanding of our solar system is constantly expanding as we learn more and more about space and develop new technologies to explore it. Our solar system is vast and fascinating. Check out the links on the website and explore them in depth.

Our Solar System: 10 Need-To-Know Things

(taken from NASA - http://solarsystem.nasa.gov/planets/solarsystem/needtoknow)

1. What is it? Our solar system is made up of the sun and everything that travels around it. This includes eight planets and their natural satellites such as Earth's moon, dwarf planets such as Pluto and Ceres, asteroids, comets and meteoroids.2. Sun-Centered: The sun is the center of our solar system. It contains almost all of the mass in our solar system and exerts a tremendous gravitational pull on planets and other bodies.

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3. Age: Our solar system formed about 4.6 billion years ago.4. Can Stand On Them: The four planets closest to the sun -- Mercury, Venus, Earth, and Mars -- are called the terrestrial planets because they have solid, rocky surfaces.5. Can't Stand on Them: Two of the outer planets beyond the orbit of Mars -- Jupiter and Saturn -- are known as gas giants; the more distant Uranus and Neptune are called ice giants.6. Beyond Neptune: Most of the known dwarf planets exist in an icy zone beyond Neptune called the Kuiper Belt, which is also the point of origin for many comets. Ceres is the exception. It is in the main asteroid belt.7. Hard to Breathe: Many objects in our solar system have atmospheres, including planets, some dwarf planets and even a couple moons. But none of them are suitable for humans.8. Spiral Galaxy: Our solar system is located in the Orion Arm of the Milky Way Galaxy. There are most likely billions of other solar systems in our galaxy. And there are billions of galaxies in the Universe.9. Taking Measure: We measure distances in our solar system by Astronomical Units (AU). One AU is equal to the distance between the sun and the Earth, which is about 93 million miles (150 million km).10. Going the Distance: NASA's twin Voyager 1 and Voyager 2 spacecraft are the first spacecraft to explore the outer reaches of

our solar system.

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