Celestial Bodies ERAU RET Erica Ajder

Andromeda galaxy

Crab Nebula

Sombrero Galaxy

Horsehead nebula

Ultra Deep Field

Based on the article write 3 interesting facts or comments that you found from the article Share 1 interesting fact or comment with the group Article Feedback Hubble Telescope

Black Body Radiation What you think a blackbody is? A blackbody is a surface that absorbs all electromagnetic radiation All bodies with temperature give off thermal radiation As temperature increases, blackbodies emit visible light from longer wavelength or lower frequency (red) to shorter wavelength or higher frequency (blue)

Star Color/composition What is a star made of? It is made up of various gaseous elements The center of a star is dense; the outer layers are less dense and make up the star’s atmosphere What does the spectrum of a star tell you about the star? The spectrum of a star gives information about the composition and temperature of a star

Emission Spectrum What do you think Emission Spectrum means? Emission lines are lines made when certain wavelengths, of light, or colors, are given off by hot gasses. Each elements produces a unique set of emission lines, which assists in identifying the elements in a star. This set of lines is known as the emission spectrum

Absorption spectrum What do you think absorption spectrum is? A star’s spectrum is made of dark emission lines. A star’s atmosphere absorbs certain colors of light, which causes black lines to appear. Because a star’s atmosphere absorbs some colors of light, the spectrum of a star is called an absorption spectrum.

Example of Each Spectrum Type What do you notice about the absorption & emission spectrum of hydrogen?

Emission Spectrum of Common Star Elements

Kirchoff’s Laws 1. A hot solid object produces light with a continuous spectrum 2. A hot gas at low pressure produces an emission spectrum 3. Light passing through a cool gas will produce an absorption spectrum

Examples of Laws 1. Light passing through Solid Object 2. Hot gas at low temperature 3. Light passing through a cooler gas

Write down which elements are observed in this star 1

2

Hertzsprung-Russell Diagram H-R Diagram

ParalLax the apparent shift in the position of an object when viewed from different locations Courtesy of Holt Reinhart

Apparent & Absolute magnitude What do you think is the difference between Apparent & Absolute Magnitude? Apparent Magnitude - the brightness of a star as seen from Earth (how bright it looks to you) Absolute Magnitude is the actual measured brightness of a star The absolute magnitude of our sun is 4.8 but because it is so close it appears to be a (extremely bright)

Types of Stars What stage of a star’s life cycle lasts the longest? Main sequence -2 nd & longest stage What stages could a star enter after main sequence? Red Giant or Red Supergiant Red Giants can be 10x larger than our sun Supergiants can be 100x larger than our sun

Types of stars Continued What stage could a star the size of our sun or smaller enter after being a Red Giant? White Dwarf – a small hot dim star that is leftover center of an old star White Dwarfs run out of hydrogen and no longer fuse hydrogen to make helium

When stars get old What happens when a massive star collapses and throws its outer layers into space? Supernova - can be brighter than an entire galaxy for several days Particles at the core collapse to form neutrons If the mass of this new star is about 2 times the mass of the sun, a neutron star may form A pulsar is a spinning neutron star

Name the type of star in each picture below

Sun Sizes compared

3 Types of Galaxies What are the 3 types of galaxies? Spiral, Elliptical, Irregular Identify the 3 types below Irregular- galaxies that do not fit into any other category Spiral- galaxies that have a bulge in center & arms that spiral outward Elliptical- 1/3 of all galaxies are massive blobs of stars & contain mostly older stars

Which of the following forces holds galaxies together? A. Electrical B. Electromagnetic C. Gravitational D. Magnetic

Which one of the following properties do astronomers use to determine temperature & Composition of stars? A.the apparent motion of stars B.the absolute magnitude of stars C.the apparent magnitude of stars D.the absorption spectrum of stars

What type of star? Astronomers estimate that in another 5 billion years, the Sun will burn up all of its hydrogen fuel. At the end of this 5- billion year pd., what kind of star will the Sun change into? A.red giantC. white dwarf B.red dwarfD. red supergiant Which of the following colors would indicate to an astronomer that a star has a very high surface temperature? F.blue G.orange H.red I.yellow

Properties of waves What does a wave carry? Energy What are the 4 properties of a wave? Frequency – # of waves per sec (Hertz) Wavelength – distance between any pt on a wave to identical pt on next wave Amplitude – distance particles vibrate from rest position Wavespeed – speed a wave travels wavelength

Types of waves What are the 2 main types (not examples) of waves? Transverse - waves in which the particles vibrate perpendicularly to the direction wave is traveling; has crest & troughs; medium not required – examples? Electromagnetic waves, rope waves Longitudinal - waves in which the particles vibrate back & forth along the path that waves move; has compressions and rarefactions; must have a medium – examples? Sound waves, seismic waves, spring waves

Electromagnetic (EM) Waves Name as many types of EM waves that you can in 2 min with your groups Visible Light Radio waves Microwaves X-rays Gamma Infrared Ultraviolet All waves produced by stars & galaxies

Electromagnetic spectrum Place the previously discussed electromagnetic waves on the spectrum chart

Use chart to give examples of each type of wave Insect use to see flowers

Dangers of waves Which waves are considered dangerous if exposed to large amounts? X-rays, Gamma & Ultraviolet Why? The higher the frequency and the shorter wavelength the more dangerous the wave because they have more ENERGY and can travel directly through matter Which of the 3 do we have most contact with on a regular basis? Ultraviolet

Protection How can we protect ourselves from dangerous waves? Sunblock Protective clothing UV blocking sunglasses Stay out of the sun Lead aprons when receiving x-rays

Planet introduction All planets are bound to stars because of _?_ Refresher: All planets move in an __________around a star Planets move fastest when ____________ (closer/further) to its star The further a planet is from the sun the _________ it takes to orbit the sun The further a planet is from the sun the _________ the gravitational pull ellipse closer longer weaker

Solar system sizing

Hodometer Lab Follow directions in order to create a scaled down version of the planets in order to envision planet spacing in our solar system

Celestial body project Each one of you is going to do a project on one celestial body You will be teaching your celestial body to the class through a power point presentation next week