Life Cycle of a Star Introduction to Stellar

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Life Cycle of a Star Introduction to Stellar Stages & Blackbody Spectrum

Life Cycle of a Star Introduction to Stellar Stages & Blackbody Spectrum

Table Talk w/Chalk 1. 2. 3. 4. 5. How does the sun produce energy?

Table Talk w/Chalk 1. 2. 3. 4. 5. How does the sun produce energy? How is fusion different from bonding? Do small stars or large stars burn faster? Do small stars or large stars burn hotter? When does fusion stop in a red supergiant? Why? 6. What determines the life cycle of a star? 7. Where do stars begin to form?

The Big Bang and Soon After The “Cosmic Microwave Background Radiation” (CMB), Present Day

The Big Bang and Soon After The “Cosmic Microwave Background Radiation” (CMB), Present Day "Ilc 9 yr moll 4096" by NASA / WMAP Science Team - http: //map. gsfc. nasa. gov/media/121238/ilc_9 yr_moll 4096. png. Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Ilc_9 yr_moll 4096. png#mediaviewer/File: Ilc_9 yr_moll 4096. png

The Big Bang and Soon After (ctd. ) Temp Cools from 10 Billion K

The Big Bang and Soon After (ctd. ) Temp Cools from 10 Billion K to 1 Billion K "Scheme of nuclear reaction chains for Big Bang nucleosynthesis" by Pamputt - Own work ; vectorisation de The main nuclear reaction chains for Big Bang nucleosynthesis. jpg. Licensed under CC BY-SA 4. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Scheme_of_nuclear_reaction_chains_for_Big_Bang_nucleosynthesis. svg#mediaviewer/File: Scheme_of_nuclear_reaction_chains_for_Big_Bang_nucleosynthesis. svg

Life and Death of Stars Recapitulation of How Elements are Formed

Life and Death of Stars Recapitulation of How Elements are Formed

Life Cycle of a Star

Life Cycle of a Star

Life of a Small Star Around the mass of 1 Sun up to ~5

Life of a Small Star Around the mass of 1 Sun up to ~5 Solar Masses

“Before she became a star…” Nebula – Cloud of Gas (mostly H) "Eagle nebula

“Before she became a star…” Nebula – Cloud of Gas (mostly H) "Eagle nebula pillars" by Credit: NASA, Jeff Hester, and Paul Scowen (Arizona State University) - http: //hubblesite. org/newscenter/newsdesk/archive/releases/2003/34/image/a. Licensed under Public Domain via Wikimedia Commons - http: //commons. wikimedia. org/wiki/File: Eagle_nebula_pillars. jpg#mediaviewer/File: Eagle_nebula_pillars. jpg

“On her way to the audition…” Protostar (NOT A STAR YET) "Witness the Birth

“On her way to the audition…” Protostar (NOT A STAR YET) "Witness the Birth of a Star" by NASA/JPL-Caltech/R. Hurt (SSC) - Image of the day gallery. Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Witness_the_Birth_of_a_Star. jpg#mediaviewer/File: Witness_the_Birth_of_a_Star. jpg

Once it’s hot enough… NUCLEAR FUSION "Fusioninthe. Sun" by Borb. Licensed under CC BY-SA

Once it’s hot enough… NUCLEAR FUSION "Fusioninthe. Sun" by Borb. Licensed under CC BY-SA 3. 0 via Wikimedia Commons - http: //commons. wikimedia. org/wiki/File: Fusioninthe. Sun. svg#mediaviewer/File: Fusioninthe. Sun. svg

How Fusion Works (Yes, you can actually know this. ) • Need very high

How Fusion Works (Yes, you can actually know this. ) • Need very high temperatures, ~10 -15 million K • Protons overcome repulsion – Stick due to “Strong Nuclear Force” • Mass of 4 p+ > Mass of 1 He – Where did the missing mass go?

How Fusion Works (ctd. ) • E = mc 2 • Lost mass is

How Fusion Works (ctd. ) • E = mc 2 • Lost mass is converted to energy! • Basis for all fusion processes that release (or absorb) energy

“A star is born!” Main Sequence – Doing H Fusion "The Sun in extreme

“A star is born!” Main Sequence – Doing H Fusion "The Sun in extreme ultraviolet" by NASA - [1]. Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: The_Sun_in_extreme_ultraviolet. jpg#mediaviewer/File: Th e_Sun_in_extreme_ultraviolet. jpg "Sirius A and B Hubble photo" by NASA, ESA, H. Bond (STSc. I), and M. Barstow (University of Leicester) - http: //www. spacetelescope. org/images/html/heic 0516 a. html. Licensed under CC BY 3. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Sirius_A_and_B_Hubble_photo. jpg#mediaviewer/File: Siri us_A_and_B_Hubble_photo. jpg

After billions of years… • H fuel runs out in the middle, He accumulates

After billions of years… • H fuel runs out in the middle, He accumulates • Not hot enough to fuse together He atoms • Gravity starts to take over!

“She suffered a partial collapse…” A Small Star Evolves • Outside comes in, REHEATING

“She suffered a partial collapse…” A Small Star Evolves • Outside comes in, REHEATING DUE TO GRAVITATIONAL POTENTIAL • It’s Red Giant time! • Hot enough to fuse He into C, N • (See next slide for size comparison)

Red Giant Stage – An Old “Small” Star "The life cycle of a Sun-like

Red Giant Stage – An Old “Small” Star "The life cycle of a Sun-like star (annotated)" by ESO/M. Kornmesser - http: //www. eso. org/public/images/eso 1337 a/. Licensed under CC BY 4. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: The_life_cycle_of_a_Sun-like_star_(annotated). jpg#mediaviewer/File: The_life_cycle_of_a_Sun-like_star_(annotated). jpg

“So explosive!” Losing the Shell – Planetary Nebula • Fusion of He to C,

“So explosive!” Losing the Shell – Planetary Nebula • Fusion of He to C, N releases much more energy • Gravity can’t hold it together • Loses the outer gases – Planetary Nebula – NOTHING TO DO WITH PLANETS "Seeing into the Heart of Mira A and its Partner" by ESO/S. Ramstedt (Uppsala University, Sweden) & W. Vlemmings (Chalmers University of Technology, Sweden) http: //www. eso. org/public/images/potw 1447 a/. Licensed under CC BY 4. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Seeing_into_the_Heart_of_Mira_A_and_its_Partner. jpg# mediaviewer/File: Seeing_into_the_Heart_of_Mira_A_and_its_Partner. jpg

Another Planetary Nebula Colors = different elements • helium (blue) • oxygen (green) •

Another Planetary Nebula Colors = different elements • helium (blue) • oxygen (green) • nitrogen (red) "M 57 The Ring Nebula" by The Hubble Heritage Team (AURA/STSc. I/NASA) - http: //hubblesite. org/newscenter/archive/releases/1999/01/image/a/ (direct link). Licensed under Public Domain via Wikimedia Commons - http: //commons. wikimedia. org/wiki/File: M 57_The_Ring_Nebula. JPG#mediaviewer/File: M 57_The_Ring_Nebula. JPG

“How do you feel inside? ” The Leftover Core – White Dwarf • Core

“How do you feel inside? ” The Leftover Core – White Dwarf • Core is white hot, but NOT hot enough to fuse C with C • Most white dwarfs simply fade out over a LONG time – Theoretical “black dwarf” is typical fate • But there may be another way to go out! "Sirius A and B Hubble photo. editted" by Bokus http: //upload. wikimedia. org/wikipedia/commons/f/f 3/Sirius_A_and_B_Hubble_photo. jpg. Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Sirius_A_and_B_Hubble_photo. editted. PNG#mediaviewe r/File: Sirius_A_and_B_Hubble_photo. editted. PNG

Type Ia Supernova “She got help from a friend…” Enough energy is released to

Type Ia Supernova “She got help from a friend…” Enough energy is released to fuse C into elements heavier than C. "Progenitor IA supernova" by NASA, ESA and A. Feild (STSc. I); vectorisation by chris 論 - http: //hubblesite. org/newscenter/archive/releases/star/supernova/2004/34/image/d/. Licensed under CC BY 3. 0 via Wikimedia Commons - http: //commons. wikimedia. org/wiki/File: Progenitor_IA_supernova. svg#mediaviewer/File: Progenitor_IA_supernova. svg

Type Ia Supernova – Example High-Z Supernova Search Team/HST/NASA

Type Ia Supernova – Example High-Z Supernova Search Team/HST/NASA

Life of a Large Star Around the mass of 8 Suns and up

Life of a Large Star Around the mass of 8 Suns and up

Life Cycle of a Star

Life Cycle of a Star

Large Stars on the Main Sequence More mass → More gravitational energy → Higher

Large Stars on the Main Sequence More mass → More gravitational energy → Higher core temperature → Faster fusion rate → Shorter time on the main sequence "Hot and brilliant O stars in star-forming regions" by ESO - http: //www. eso. org/public/images/eso 1230 b/. Licensed under CC BY 3. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Hot_and_brilliant_O_stars_in_star-forming_regions. jpg#mediaviewer/File: Hot_and_brilliant_O_stars_in_star-forming_regions. jpg

A Large Star Evolves – Red Supergiant Stage(s) • Akin to small mass star,

A Large Star Evolves – Red Supergiant Stage(s) • Akin to small mass star, fuel runs out, core reheats, fusing He to C • Enough mass to repeat the process, fusing heavier and heavier elements – Ne, Mg, Al, for example – All the way up to Fe • Resembles an onion Betelgeuse at upper left is a red supergiant "Orion Head to Toe" by Rogelio Bernal Andreo - http: //deepskycolors. com/astro/JPEG/RBA_Orion_Head. Toes. jpg. Licensed under CC BY-SA 3. 0 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Orion_Head_to_Toe. jpg#mediaviewer/File: Orion_Head_to_Toe. jpg

“A total collapse!” End of a Large Star • Fe builds up in the

“A total collapse!” End of a Large Star • Fe builds up in the core • Not enough outward pressure – Gravity takes over • Outer layers rush in, and BOUNCE off the core – Enough energy released to fuse ANY naturally occurring element – Surplus of energy can form Au, Pb, I, etc. "HST SN 1987 A 20 th anniversary" by NASA, ESA, P. Challis, and R. Kirshner (Harvard. Smithsonian Center for Astrophysics) http: //hubblesite. org/newscenter/archive/releases/2007/10/image/a/ (direct link). Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: HST_SN_1987 A_20 th_anniversary. jpg#mediaviewer/File: HST_SN_1987 A_20 th_anniversary. jpg

The Aftermath – Neutron Stars and Black Holes "Isolated. Neutron. Star" by Original uploader

The Aftermath – Neutron Stars and Black Holes "Isolated. Neutron. Star" by Original uploader was Northgrove at en. wikipedia - Transferred from en. wikipedia. Licensed under Public Domain via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: Isolated. Neutron. Star. jpg#mediaviewer/File: Isolated. Neutro n. Star. jpg "BH LMC" by User: Alain r - Own work. Licensed under CC BY-SA 2. 5 via Wikimedia Commons http: //commons. wikimedia. org/wiki/File: BH_LMC. png#mediaviewer/File: BH_LMC. png

Other Element Formation – Cosmic Rays • High-energy particles either left over from the

Other Element Formation – Cosmic Rays • High-energy particles either left over from the Big Bang or ejected from stars/supernovae • Slam into heavier elements occasionally and split them into smaller nuclei – E. g. , Li, Be, B Earth’s Moon blocks muon cosmic rays "Moon's shadow in muons" by http: //hepweb. rl. ac. uk/pp. UKpics/POW/pr_990602. html. Licensed under Fair use via Wikipedia http: //en. wikipedia. org/wiki/File: Moon%27 s_shadow_in_muons. gif#mediaviewer/File: Moon%27 s_ shadow_in_muons. gif

Life Cycle of a Star

Life Cycle of a Star

Summary – Different Processes Make Elements • Big Bang – H, He, Li (a

Summary – Different Processes Make Elements • Big Bang – H, He, Li (a little) • Small Mass Stars – He (main sequence) – C, N (red giant) – Heavier than C (only type Ia supernova) • Large Mass Stars – He (main sequence) – C, N, etc. , all the way up to Fe (red supergiant) – All natural elements (only type II supernova) • Cosmic Rays – Li, Be, B (split off from larger atoms)

Stellar Nursery Eagle Nebula Pillars from Hubble, opposite. stsci. edu Columns: H gas What

Stellar Nursery Eagle Nebula Pillars from Hubble, opposite. stsci. edu Columns: H gas What do you notice at the top? Pillars are slowly eroded away by UV light = Evaporating Gas Globules (Eggs) denser gas uncovered

Can the color of a glowing object tell us the temperature of the object?

Can the color of a glowing object tell us the temperature of the object? Hot……. . . Hotter…. . . Hottest!

The electromagnetic spectrum Google images

The electromagnetic spectrum Google images

Blackbody Simulation

Blackbody Simulation

How do we sample the universe? Betelgeuse Red Giant making Ca and beyond. Future

How do we sample the universe? Betelgeuse Red Giant making Ca and beyond. Future supernova. p 3 steadily making He. Future C, N Orion Nebula New stars getting heavy elements. Future Earths? Rigel - Blue Supergiant making, He, C, N. Future heavy elements.

What is light?

What is light?

What do you see? By The copyright holder of this image, Christopher Down, allows

What do you see? By The copyright holder of this image, Christopher Down, allows anyone to use it, Attribution, https: //commons. wikimedia. org/w/index. php? curid=3642142

What accounts for sunlight? By The copyright holder of this image, Christopher Down, allows

What accounts for sunlight? By The copyright holder of this image, Christopher Down, allows anyone to use it, Attribution, https: //commons. wikimedia. org/w/index. php? curid=3642142

Recapitulate the Bohr Model : Shown above – Red line is 656 nm transition

Recapitulate the Bohr Model : Shown above – Red line is 656 nm transition By A_hidrogen_szinkepei. jpg: User: Szdoriderivative work: Orange. Dog (talk • contribs) A_hidrogen_szinkepei. jpg, CC BY 2. 5, https: //commons. wikimedia. org/w/index. php? curid=6273602 By Jan Homann - Own work, CC BY-SA 3. 0, https: //commons. wikimedia. org/w/index. php? curid=6504291

Sample Emissions (Plasma Light Version) • You need… – Diffraction tools (rough spectrometers) –

Sample Emissions (Plasma Light Version) • You need… – Diffraction tools (rough spectrometers) – Reference sheet of emission/absorption spectra • Your teacher will energize a few gaseous elements with an electric current • Observe the distinct wavelengths – Sample A is _______ and overall appears _______ – Sample B is _______ and overall appears _______ – Sample C is _______ and overall appears _______

Sunlight Through a Spectroscope By Fraunhofer_lines. jpg: nl: Gebruiker: Maureen. VSpectrum-s. RGB. svg: Phrood.

Sunlight Through a Spectroscope By Fraunhofer_lines. jpg: nl: Gebruiker: Maureen. VSpectrum-s. RGB. svg: Phrood. Fraunhofer_lines_DE. svg: *Fraunhofer_lines. jpg: Saperaud 19: 26, 5. Jul. 2005 derivative work: Cepheiden (talk) - Fraunhofer_lines. jpg. Spectrum-s. RGB. svg. Fraunhofer_lines_DE. svg, Public Domain, https: //commons. wikimedia. org/w/index. php? curid=7003857 Discuss: What do you think determines this pattern of light?

How do these compare to what we just saw? Richmond, Michael. http: //spiff. rit.

How do these compare to what we just saw? Richmond, Michael. http: //spiff. rit. edu/classes/phys 301/lectures/class. html

Putting the Moves Together (Pictorially) http: //www. uni. edu/morgans/astro/course/Notes/section 1/new 4. html

Putting the Moves Together (Pictorially) http: //www. uni. edu/morgans/astro/course/Notes/section 1/new 4. html

Putting the Moves Together (Verbally) • Stars release many energies of light – The

Putting the Moves Together (Verbally) • Stars release many energies of light – The spread based on temperature • Elements can absorb light on its way out – The colors based on electron transitions • Between the kinds of light released and absorbed, we can draw conclusions about the star’s temperature, composition, and other features

Challenge: 1. Order these like a human 2. Identify some present elements 3. Infer

Challenge: 1. Order these like a human 2. Identify some present elements 3. Infer some other star features Richmond, Michael. http: //spiff. rit. edu/classes/phys 301/lectures/class. html

Ordering Created by Annie Jump Cannon (a Human) Note: Not the exact spectra you

Ordering Created by Annie Jump Cannon (a Human) Note: Not the exact spectra you used. Richmond, Michael. http: //spiff. rit. edu/classes/phys 301/lectures/class. html

Further mysteries await…

Further mysteries await…

What is happening in the lower spectra? NOAO/AURA/NSF

What is happening in the lower spectra? NOAO/AURA/NSF

Univ. Chicago Press (1943) http: //ned. ipac. caltech. edu/level 5/ASS_Atlas/Plate 23. html

Univ. Chicago Press (1943) http: //ned. ipac. caltech. edu/level 5/ASS_Atlas/Plate 23. html

Stellar Spectra – Summary • A mystery star is far away and hard to

Stellar Spectra – Summary • A mystery star is far away and hard to access directly • Star emits a continuum (spectrum) of light – Based on temperature, particles release many wavelengths • Only particular elements are present in the star • Elements absorb only particular wavelengths as the light is leaving – Energy absorbed to cause electron jumps (same as emission lines) • Based on the blanks (absorption lines), we can deduce what elements are present in greater abundance