Copy week schedule into your agenda and answer the Question of the Day

Progression of Theories Over nearly 2000 years humans have gone through several ideas about the universe. From… Geocentric to… Heliocentric to… The Big Bang

Why? Because new technology creates new evidence

Because new technology creates new evidence Why? Because new technology creates new evidence

Scientists and innovation In the 1880s scientists began to make theories and discoveries that would prove that light was transmitted in the form of a wave. This discovery would eventually allow scientists to see further into space and make many discoveries about the universe.

Using Electromagnetic Waves in Space

Parts of a wave The crest is the highest point of the wave. The trough is the lowest point.

Wavelength is the distance between the two of the same adjacent points on the diagram. Amplitude is the height of the wave from its resting position.

The higher the amplitude of a wave, the more energy the wave has. The shorter the wavelength of a wave, the more energy the wave has. Slinky Demonstration

Frequency The frequency and wavelength of a wave determines how much energy a wave has. Frequency is the number of wave crests that pass a point during one second. A frequency of one cycle per second is measured in a unit called Hertz ( Hz).

The Electromagnetic Wave The magnetic and electric fields of an electromagnetic wave are perpendicular to each other and to the direction of the wave.

Electromagnetic waves are created by the vibration of photons Electromagnetic waves are created by the vibration of photons . Photons………... --They have zero mass. --They have no electric charge. --They are stable. --When in empty space, they travel at the speed of light. --They carry energy and momentum which are dependent on the frequency. --They can have interactions with other particles such as electrons. --They can be destroyed or created by many natural processes.

Draw in the wave on your paper now

What tools are used to collect and focus this electromagnetic radiation from space? Telescopes Satellites

Objects in space, such as planets and comets, giant clouds of gas and dust (nebulae), and stars and galaxies, emit light at many different wavelengths.

By studying the radio waves originating from these sources, astronomers can learn about their composition, structure, and motion. Radio astronomy has the advantage that sunlight, clouds, and rain do not affect observations.

Radio Telescopes

Images from Radio Telescopes The above image shows the Carbon Monoxide (CO) gases in our Milky Way galaxy. By studying the radio waves originating from these sources, astronomers can learn about their composition, structure, and motion. Radio astronomy has the advantage that sunlight, clouds, and rain do not affect observations.

Because microwaves can penetrate haze, light rain and snow, clouds and smoke, these waves are good for viewing the Earth from space. (Satellite images of Earth) Scientists have discovered cosmic microwave background radiation. This radiation, which fills the entire Universe, is believed to be a clue to it's beginning, something known as the Big Bang.

Satellite image of Amazon river using microwaves

Satellites, like the Infrared Astronomy Satellite (IRAS) look up into space and measure the infrared waves coming from things like large clouds of dust and gas, stars, and galaxies.

Satellite that collects infrared waves If near infrared is reflected off of healthy vegetation, what do you think the red square shaped areas are in the lower left of the image?

Images using Visible Light Clouds Jupiter

Many scientists are interested in studying the invisible universe of ultraviolet light, since the hottest and the most active objects in the cosmos give off large amounts of ultraviolet energy.

Top images are Ultraviolet Waves Bottom are Visible Light waves Three different galaxies taken by NASA's Ultraviolet Imaging Telescope (UIT) on the Astro-2 mission.

Image of the Sun taken at an Extreme Ultraviolet wavelength

Many things in space emit X-rays , among them are black holes, neutron stars, binary star systems, supernova remnants, stars, the Sun, and even some comets! Since almost no X-rays are able to penetrate our atmosphere from outer space, we have to put X-ray telescopes and detectors on satellites.

Here is what the Sun looked like in X-rays on April 27th, 2000 Here is what the Sun looked like in X-rays on April 27th, 2000. (Taken by the Yokoh satellite.)

When one of the stars in a binary star system is a black hole or a neutron star, material is pulled off the normal star. This materials spirals into the black hole or neutron star and heats up to very high temperatures. When something is heated to over a million degrees, it will give off X-rays!

X-ray Images of objects in space Comet Remains of a Supernova Remains of a Supernova

Gamma ray astronomy did not develop until it was possible to get our detectors above all or most of the atmosphere. The first gamma-ray telescope (1961) picked up fewer than 100 cosmic gamma-ray photons. Gamma-ray telescopes use a process called Compton scattering, where a gamma-ray strikes an electron and loses energy, similar to a cue ball striking an eight ball.

Satellite that collects Gamma Waves

The Moon seen with Gamma Waves

Gamma Visible

Gamma Ray Bursts from Deep Space Gamma-ray bursts can release more energy in 10 seconds than the Sun will emit in its entire 10 billion-year lifetime! So far, it appears that all of the bursts we have observed have come from outside the Milky Way Galaxy.