Objectives Give a brief overview of how scientists think stars and planets formed. List and describe evidence from our solar system that supports that overview. List and describe evidence from outside our solar system that supports that overview. What is a nebula? What is a protostar? Name an excellent example of a star birth region. Why are the Terrestrial planets dense but the Jovian planets are not? Name and describe the two most common ways to find exoplanets (1. Doppler Shift a.k.a. radial velocity, 2. Transit). DEMONSTRATION MATERIALS: Stool, green spinner and masses Sunlamp and radiometer

How Stars and Planets are Born Birth of Stars Nebular Hypothesis Solar Nebula Theory Bring paper scraps for attendance questions Orion video Star birth simulation video View the BBC clip at http://www.bbc.co.uk/programmes/p009gxf2 http://www.unm.edu/~astro1/101lab/lab9/lab9_C1.html (when searching, try: Nebular Hypothesis or Solar Nebula Theory or just birth of stars) Nasa-Jpl-CalTech

Star/Planet Birth Nebula = large gas and dust cloud From 1609 to early 1900s, almost every faint, fuzzy object was called a nebula. Modern definition on slide Plural: nebulae

Star/Planet Birth Piece of nebula contracts due to gravity and shock waves Often other stars forming at same time from other parts of gas cloud Shock wave is from a sudden change in pressure, density or temperature, similar to a sound shock wave but not from sound, instead from energy

Star/Planet Birth That piece of contracting gas cloud Flattens Rotates faster

Orion Nebula (video clip) - Great example of a Star Birth Region http://www.spitzer.caltech.edu/video-audio/381-hiddenuniverse026-Orion-Nebula-Gallery-Explorer- Orion Nebula is an excellent example of a star birth region – 2:16 video Handout paper to summarize steps of star/planet birth

Star/Planet Birth Center: Most matter Protostar  Star Protostar = Large object From contraction/collapse of part of a large gas cloud Will become a star Protostar is cooler pre-star seen in infrared Begins as invisible concentration of gas Contracts and grows hotter and hidden in cocoon but detectable in infrared Newborn star becomes visible as it blows the dust cocoon away

Star/Planet Birth Disk: Smaller objects stick and collide to form larger objects

Star/Planet Birth Disk: Warmer near protostar Light elements blown away Cooler further out Light elements like H stay around Water freezes Big, less dense planets form from H

Star/Planet Birth Happens within cocoon of gas and dust Often bi-polar jets Read title…happens within…

Star/Planet Birth Star Birth Protostar turns on: Fusion Protostar  Star Strong stellar winds Birth of stars when fusion turns on; this can happen throughout nebula, not just at center; need enough mass for fusion to start Strong stellar winds (star itself and neighbor stars)

Star/Planet Birth Nebula cleared: Heavy stuff by Light stuff by Collisions and close encounters Planet Birth Light stuff by Strong stellar winds Planet birth from heavy collisions How a nebula gets cleared: collisions and winds and then looks similar to our solar system From 1609 to early 1900s, almost every faint, fuzzy object was called a nebula. Modern definition on slide Plural: nebulae Nasa/JPL - Caltech

Star/Planet Birth Summary 1. 2. 3. 4. 5. 6.

Star/Planet Birth Summary Nebula Contracts, Flattens, Rotates Disk with Protostar Contracts to form Cocoon around Protostar Solar wind blows Cocoon away and left with Star Disk forms Planets

Star/Planet Birth Star Birth Simulation http://www.youtube.com/watch?v=YbdwTwB8jtc&playnext=1&list=PLFC84C8CBA3C1B6D6&feature=results_video 1.5 minute video of simulated star birth

Evidence for Star & Planet Birth a. From our solar system b. From outside our solar system

Evidence from our Solar System Model Today’s Solar System Sun at center (most of mass) Sun and planets – not much else Flat/planar for most part Preferred direction of rotation and revolution Composition (Mostly H, He like stars and gas clouds)

Evidence from our Solar System Model Today’s Solar System Smaller objects form larger objects Planet impacts, seen impacts on our moon, Hubble saw asteroid belt collision in 2010

Evidence from our Solar System Model Today’s Solar System Smaller objects form larger objects Meteoroids and comets Craters

Craters Moon Craters observation

Moon

Manicouagan Crater, Quebec, Canada; 215 million years old; largest visible caused by 5 km/3 mi meteorite (thought to be 6th largest); most visible ring is 40 mi wide with larger less visible ring at 60 mi wide

Mars

Gaspra http://www2.jpl.nasa.gov/galileo/images/gaspra.gif 12 mi X 7 mi Cratered asteroid in asteroid belt http://www2.jpl.nasa.gov/galileo/images/gaspra.gif 12 mi X 7 mi

Miranda (moon of Uranus) Big collision on Miranda Miranda (moon of Uranus)

Craterers Comets Meteoroids Comet image

Comet Tempel 1 Size ~ 1/2 Manhattan (14kmX4km) Probe crashed into comet Size ~ 1/2 Manhattan (14kmX4km) http://apod.nasa.gov/apod/ap110216.html Size: ~1/3 Manhattan ~8kmX5km Impacted on July 4, 2005 by part of the NASA Deep Impact probe

Evidence from our Solar System Model Today’s Solar System Asteroid belt Kuiper Belt Oort Cloud

Distant leftovers – Asteroid belt Kuiper Belt Oort Cloud Credit: NASA/JPL-Caltech/T. Pyle (SSC)

Evidence from our Solar System Model Today’s Solar System Smaller objects form larger objects Meteoroids and comets Craters Asteroid Belt, Kuiper Belt, Oort Cloud Mini “systems” like Saturn and Jupiter

Evidence from our Solar System Model Today’s Solar System Terrestrial vs. Jovian planets Outer solar system is cooler Big, less dense planets form from H Frost line where inside of it only metal and rock can condense; outside of it gases condense and Jovian can take on H and He condensing; rocky planets actually took longer time to form and collect more mass from collisions

Rotation and Revolution How does rotation and revolution happen? Everything is in motion. Random motion causes pockets of rotation/revolution. Why so fast? Angular momentum demo Can do demo standing on spinning platform with weights in hands and then pull arms in to go faster and stretch arms out to stop/slow down

Collisions, close encounters and solar wind clear nebula Demo – Crooke’s radiometer Video explanation https://www.youtube.com/watch?v=llxqNcipTwA Light pressure demo with sunlamp/light bulb and radiometer; temperature and pressure difference – black The thermal difference in the silver and black sides makes it spin Video is for at home watching – explanation of how Crooke’s radiometer works

Evidence from our Solar System Model Today’s Solar System Smaller objects form larger objects Meteoroids and comets Craters Asteroid Belt, Kuiper Belt, Oort Cloud Mini “systems” like Saturn and Jupiter Terrestrial vs. Jovian planets Rotation and revolution

Evidence for Star/Planet Birth a. From our solar system b. From outside our solar system Now outside SS

Evidence from beyond our solar system Gas clouds in Milky Way (H, He) http://apod.nasa.gov/apod/ap990224.html

Pipe Nebula Pipe Nebula – dark area in lower left http://apod.nasa.gov/apod/ap970621.html

Dark absorption nebula: Molecular Cloud Barnard 68 http://apod.nasa.gov/apod/ap990511.html

Horsehead Nebula in Milky Way and Orion

Orion constellation with nebula labels 200 to 1300 ly away M78 is Reflection Nebula (M or Messier object, 110 of them) http://wordlesstech.com/wp-content/uploads/2010/12/orion-over-snowy-ireland3.jpg

http://apod.nasa.gov/apod/ap131231.html

Orion Nebula – star birth! 1300 ly away http://www.telescopes.cc/m42.htm

North America nebula on left and Pelican nebula on right separated by dark absorption cloud (two emission nebulae, host star excites nearby gas) http://antwrp.gsfc.nasa.gov/apod/ap060816.html

Witch Head Nebula

http://apod.nasa.gov/apod/ap121101.html with Rigel Witch Head reflection (starlight scatter from dust) nebula near Rigel in Orion, 900 ly http://apod.nasa.gov/apod/ap121101.html with Rigel

Stars form in groups from the same gas cloud Pleiades, 7 Sisters, M45 In constellation Taurus All about same age, 100 million years ago Open cluster, hot blue stars with high luminosity

Stars form in groups from the same gas cloud http://antwrp.gsfc.nasa.gov/apod/ap060403.html Star cluster in constellation Sagittarius

M33 Strong stellar winds sculpt the nebulae Recall Crooke’s Radiometer Demo Triangulum Galaxy

50 ly across 4,500 ly away, Monoceros Nebula Rosette Nebula Monoceros nebula and constellation 50 ly across 4,500 ly away, Monoceros Nebula

Trifid Nebula - http://antwrp.gsfc.nasa.gov/apod/ap971208.html 3 dark clouds for trifid: Red emission nebula (excited atoms from recapture of electrons) and blue reflection nebula Trifid Nebula - http://antwrp.gsfc.nasa.gov/apod/ap971208.html

Part of Trifid

Evidence from beyond our solar system Gas clouds in Milky Way (H, He) Stars form in cocoons With bipolar jets

Cocoons from Hubble http://www.spacetelescope.org/images/screen/heic0917ab.jpg

Stars form in cocoons With bipolar jets

Stars form in cocoons With bipolar jets

Cocoons on edges of this nebula; Carina Nebula, stellar nursery 7500 ly away Sun to Oort Cloud is 100,000 AU = 1.87 LY http://hubblesite.org/newscenter/archive/releases/2010/13/image/a/

Infrared Spitzer view of west coast of Mexico in North America nebula – star birth area http://www.spitzer.caltech.edu/images/3513-ssc2011-03b-North-America-Nebula-Disappears

http://www. spitzer. caltech http://www.spitzer.caltech.edu/images/3511-ssc2011-03c-Babies-in-the-North-America-Nebula

Evidence from beyond our solar system Gas clouds in Milky Way (H, He) Stars form in cocoons With bipolar jets Disks of material around stars

Disks of material around stars

Disks of material around stars

Disks of material around stars

Evidence from beyond our solar system Gas clouds in Milky Way (H, He) Stars form in cocoons With bipolar jets Disks of material around stars Strong stellar winds sculpt birthing gas clouds

Strong stellar winds sculpt birthing gas clouds

M16 Eagle Nebula

Cloud broke off from (part of) Carina Nebula; imagine:  it could be perceived as a superhero flying through a cloud, arm up, with a saved person in tow below http://antwrp.gsfc.nasa.gov/apod/ap030630.html

Evidence for Star/Planet Birth from Beyond Our Solar System Gas clouds in Milky Way (H, He) Stars form in cocoons With bipolar jets Disks of material around stars Strong stellar winds sculpt birthing gas clouds Exoplanets

Exoplanets NASA Exoplanet Archive 11/1/2016 3,402 Confirmed Planets 575 Multi-Planets Systems 4,696 Kepler Candidates Kepler Spacecraft 2009 to look for Earth-like planets in the Milky Way Galaxy Kepler uses a Photometer and the transit method to find planets; launched in 2009 http://exoplanetarchive.ipac.caltech.edu/

http://exoplanetarchive.ipac.caltech.edu/

How to Find Planets Transit (most common) Doppler Shift (aka Radial Velocity) Others: http://planetquest.jpl.nasa.gov/page/methods Direct Imaging, taking pictures Gravitational microlensing Astrometry, miniscule movements Transit method (306 planets discovered) used to be the most common but now it is Radial Velocity (536 planets discovered) Astrometry, miniscule movements lead us to believe there is a planet 9 but not confirmed or found yet; also due to trans-Neptunian object locations Website has a great video representation of the 5 methods

Finding a planet – Transit Planets can block a little light from their parent star causing a slight dip in the light Searching for shadows http://kepler.nasa.gov/Mission/faq/

Finding a planet – Doppler Shift Planets tug on their parent stars causing a slight wobble in the star Watching for wobble http://planetquest.jpl.nasa.gov/page/methods

First visible light picture of an exo-planet (from Hubble)! - 2008 Explanation: Fomalhaut (sounds like "foam-a-lot") is a bright, young, star, a short 25 light-years from planet Earth in the direction of the constellation Piscis Austrinus. In this sharp composite from the Hubble Space Telescope, Fomalhaut's surrounding ring of dusty debris is imaged in detail, with overwhelming glare from the star masked by an occulting disk in the camera's coronagraph. Astronomers now identify, the tiny point of light in the small box at the right as a planet about 3 times the mass of Jupiter orbiting 10.7 billion miles from the star (almost 23 times the Sun-Jupiter distance). Designated Fomalhaut b, the massive planet probably shapes and maintains the ring's relatively sharp inner edge, while the ring itself is likely a larger, younger analog of our own Kuiper Belt - the solar system's outer reservoir of icy bodies. The Hubble data represent the first visible-light image of a planet circling another star. http://antwrp.gsfc.nasa.gov/apod/ap081114.html

Exoplanet Missions Kepler – transit method Spitzer – infrared Hubble – visible CoRoT – ESA decommissioned - transit Ground Based Telescopes Future: TESS (2017) and JWST (2018) Kepler – 2006 Spitzer – 2003 with other missions too CoRoT – first dedicated mission in 2006 TESS – Transiting Exoplanet Survey Satellite (NASA) JWST – James Webb Space Telescope (NASA)

Jupiter’s mass is over 300 times that of Earth; 10 times the diameter; about 12 Earth years to revolve ~ 4000 days (Earth is at 0.003 mass and 365 days) Show where Jupiter is and where Earth is on plot

Tutorials on temperature and solar system Earth

Exoplanets - Outside Our Solar System Many other planets are being found HUGE NEWS, SEVEN EARTH-SIZED WORLDS ORBITING A RED DWARF, THREE IN THE HABITABLE ZONE http://www.universetoday.com/133556/huge-news-seven-earth-sized-worlds-orbiting-red-dwarf-three-habitable-zone/ TRAPPIST-1 planetary system, about 40 LY away with a cooler, red dwarf star (12x less massive than our sun) E, f, g are habitable – Earth-like & could have liquid water; largest solar system found yet (outside ours); star is a little larger than Jupiter The initial discovery was made by TRAPPIST, the TRAnsiting Planets and PlanetesImals Small Telescope. Additional planets were subsequently identified using TRAPPIST and the Spitzer space telescope, the Very Large Telescope, UKIRT, the Liverpool Telescope and the William Herschel Telescope.

Sunset Part 2 10 Observation Points Started Tuesday, Mar. 28 Due: Apr. 25 Read details on class website about what to turn in for full credit.

Homework & Updates Watch this BBC clip about exoplanets: http://www.bbc.co.uk/programmes/p009gxf2 Observations: Star Gazing, Telescopes & Moon Craters (60 pt.) March 30, tonight, Eisenhower Community Center, Hopkins, MN Need reservation and ask a worker to show you some constellations in the sky April 1, Saturday, Baylor Park, Eagle Lake Observatory, Norwood-Young America, MN Raquel will be there about 8-9pm. Find her with the lit-up clipboard. If you miss me, have a volunteer at a telescope sign your paper. April 4 & 6, Tuesday & Thursday, Jackson Middle School, Champlin, MN April 7, Friday, Bell Museum, University of MN, Minneapolis, MN Times and directions on class website Observation Option: Univ. of MN Public Lectures – Only Do 1! Tues, Apr 4, 7pm, Bell Museum, Exploring the Mysteries of the Sun: Explosions on our Closest Star (find Raquel for 10 points) Thur, Apr 20, 7pm, Ted Mann Concert Hall, A Deeper Understanding of the Universe from 1.2 miles Underground (find Raquel for 10 points) View the BBC clip at http://www.bbc.co.uk/programmes/p009gxf2

Test 2 Results Multiple Choice curved by 2 points Average: 78% Test questions posted at front and on office doorway Check for Scantron mistakes One student got 100%