11 Pages
Unlock Document

Astronomy & Astrophysics
Michael Reid

Astronomy Notes for the Final Exam Chapter 5 Key conceptsy Rate of energy flow is called power and its measured in watts y A spectrum is the rainbow of light split from a prism It forms white light when all the colours are mixed y Light interacts with matter in 4 basic ways o Emission when a light source emits visible light Ie A light bulb o Absorption when something is put near a light source and that thing absorbs some of the light warming the object Materials that absorb light are called opaque o Transmission some forms of matter transmit light letting it go through Materials that transmit light is called transparent o Reflectionscattering light can bounce off matter Reflection is when it bounced off in a general direction and scattering is when it goes in more than one direction y Properties of light o Wavelengths distance from one peak to the next or one trough to the next Their frequency is the number of peaks passing by any point each second o Wavelength X frequencyspeed o Light is called an electromagnetic wave because light waves are vibrations of both electric and magnetic fields caused by the motions of charged particleso speed of light300 000kmso the longer the wavelength the lower the frequency and vice versa o photons light particles Light is both a particle and a wave y Spectrumso Electromagnetic spectrum complete spectrum of light o Light itself is called electromagnetic radiation o Complete spectrum shortest to longest wavelengthGamma raysX raysUltravioletVisiblemiddle InfraredMicrowavesRadioy Wavelengths LongestShortest R M IVU X G Energylowest highesto The three basic types of spectra are called Continuous spectrum y Rainbow of colour broad range of wavelengths without interruptionEmission line spectrum y when a thin or low density cloud only emits light at specific wavelengths depending on the clouds composition and temperature Shows emission lines against a black backgroundAbsorption line spectrum y When a cloud of gas lies between the source of light The cloud absorbs light at specific wavelengths letting only a few go through Shows dark absorption lines y Spectra of objects depend on only one thing the objects temperaturey Blackbody radiation a type of continuous spectrum that depends only on the objects temperature Hotter objects emit more light at shorter wavelengths and emit more radiation per unit surface area are every wavelength y The sun emits about 5800 k y the Doppler effect o moving train and sound wave example o if an object is moving towards us the light waves bunch up between us and the object so that the entire spectrum is shifted to short wavelengths o The Doppler shift of an object coming towards us is called a blueshift o If an object is moving away from us its light is shifted to longer wavelengths and its called a redshifto Looking at pictures of spectrums when the red line moves more to the right its being redshifted if the blue line moves more to the left its being blueshifted o The Doppler shift can only tell us of stars that are coming closer or moving away from us not stars that are moving across our visionChapter 7 key concepts y Quick notes from chapter 6 o Telescopes have 3 powersLight gatheringseeing farther objectsResolutionseeing more detailMagnificationnot important because you can do it on photoshop latery Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune NO MORE PLUTO y My very eccentric mother just served us nachos y The solar system is divided into two main groups of planets the inner solar system and the outer solar system y The inner solar system has in order from closest to the sun Mercury Venus Earth Mars o These are the terrestrial planets y The outer solar system has Jupiter Saturn Uranus Neptune o These are the jovian planetsy Asteroids and comets o There is an asteroid belt between mars and Jupiter Asteroids are mostly made of metal and rock o There are comets in the kuiper belt located beyond Neptunes orbit o Beyond this even more comets orbit the sun in a distant spherical region called the Oort CloudSun98 hydrogen and helium 2 other elements
More Less

Related notes for AST101H1

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.