Astronomy 110 Exam 2

What are the three components to measuring radiation?

Collect and focus light, sort the light/radiation by wavelengths, detect and record data

What are similarities between types of radiation?

Each type of radiation or wave is an emission of light.

What is the Ptolemaic model?

Earth at the center, with the sun, moon, planets, and stars revolving around it.

What is resolving power?

Focusing the light to pick up on more details

Ptolemaic Vs. Copernican

Galileo proved that the Ptolemaic model of the universe was actually incorrect. For Venus to exhibit phases as it does, it would actually have to revolve around the sun.

What did Galileo discover?

Galileo, while looking through his telescope, discovered that Venus displays phases like the Moon. If Venus were located closer to Earth than the Sun, as required in the Ptolemaic model, then Venus would always be illuminated from the back, allowing us to observe only various degrees of a crescent phase. The nearly full phases of Venus, can only occur if Venus is sometimes on the opposite side of the Sun from us.

How do Kepler's Laws apply?

Have been used, to a large extent, to accurately describe the true motion of the planets.

What is light gathering power?

How much light is gathered

What is Kepler's Third Law?

If you take the orbital period (t) of a planet and square it, you will get the same value as if you take the planet's average orbital radius (r) and cube it.

What makes a claim pseudo-science?

It is a collection of beliefs or practices mistakenly regarded as being based on scientific method. For example, astrology is something that cannot be proven or tested.

What is a blackbody?

It is a concept that hot things glow Blue is hotter than red The hotter it is, the more light it emits

How did Kepler use Tyco's data to determine the orbit of Mars?

Kepler created a method of triangulation to determine the distance of a planet from earth. Using Tycho's observations of Mars over that 2o year period, Kepler could use those points to accurately map the orbit of Mars.

What are the ways around atmosphere problems?

Location: Dry Climate, away from lights and not too cloudy

What are differences between types of radiation

Most of it is not visible light each wavelength emits a different color of light each has a different wavelength

Describe the scientific method and apply it to a topic we have learned in class recently

Spectrum. We determined that different elements emit different wavelengths which are in turn different colors. This can be used to determine the different types of elements contained in stars by looking at the wavelengths they emit.

What information is gleaned from starlight that has been separated by color?

Temperature, ingredients, distance to star

What is the concept of the electromagnetic (EM) spectrum?

The EM spectrum divides the different types of light, based on their wavelength.

What is the Copernican model?

The Earth and the other planets move around the sun.

What does the force of gravity depend on?

The mass of two objects and their distance

What is Kepler's Second Law?

The orbital speed of a planet is faster when closer to the sun and slower when farther away.

What are problems with relating astronomy to astrology?

The positions of the planets and the sun are constantly changing and none are in the same positions as when a person was born. Plus, astrology is more of a pseudo-science.

What is Kepler's First Law?

The sun is the focus and all planets revolved around it in and elliptical orbit

Why are the largest telescopes reflecting and not refracting

They are such, because it is cheaper, the bigger the telescope is, the more light it gathers, but it would be hard to create a giant lens without any imperfections. Plus, it would be too big and the glass would bend in the middle

Refracting Telescope

Uses a lens to gather and bend light

Reflecting Telescope

Uses a mirror to reflect light

In what ways is atmosphere not helpful to astronomy?

Weather, Atmosphere and light pollution

How do you apply trigonometric parallax?

You have the know distance between earth and earth on the opposite side of the sun, and then you know the angle between the two where the star is and then it is a simple matter of trigonometry to find the unknown distance

What is an absorption spectra?

a spectrum of electromagnetic radiation transmitted through a substance, showing dark lines or bands due to absorption of specific wavelengths.

What is an emission spectrum?

a spectrum of the electromagnetic radiation emitted by a source.

What is a continuous spectrum?

an emission spectrum that consists of a continuum of wavelengths.