1 2020 Div. C (High School) Astronomy Help Session Sunday, Feb. 23th, 2020 Star and Galaxy Formation and Evolution Scott Jackson Mt. Cuba Astronomical Observatory • SO competition on March 7th . • Resources – two computers or two 3 ring binders or one laptop plus one 3 ring binder – Programmable calculator – Connection to the internet is not allowed! – Help session before competition at Mt. Cuba Astronomical Observatory 2 3 4 Study aid -1 • Google each object, – Have a good qualitative feel for what the object is doing or has done within the astrophysical concepts that the student is being asked to know. – → No JS9 questions for the State competition 5 Study aid - 2 • Know the algebra behind the physics – Just because you think you have the right “equation” to use does not mean you know how to use it!!! – Hint for math problems: Solve equations symbolically BEFORE you put in numbers. Things tend to cancel out including parameters you do not need to have values for. – Know how to use scientific notation. The test – 2 parts 6 • Part 1 – multiple choice and a couple fill in the blanks • Part 2 – word problems for astrophysics there will be some algebra →Solve the equations symbolically first then put in numbers!!!! →Hint: most problems will not need a calculator if done this way 7 Stellar and galatic evolution stellar classification, spectral features and chemical composition, luminosity, Topics blackbody radiation, color index Emphasis from rules H-R diagram transitions, Neutron stars Stellar Mass and supermassive black holes, , Galactic structure and interactions, Quasars, AGNs, Galaxy Clusters ad groups of galaxies gravitational waves. Gravitational lensing, Dark Matter and dark energy, \ Warm-hot intergalactic medium (WHIM) Cosmic Microwave Background (CMB) • Kepler’s laws to answer questions relating to the orbital motions of galaxies; Use the distance modulus, Type Ia supernovas, Hubble’s law and redshift and recessional velocities and distances to galaxies 8 Quasars (AGN) Blazars – quasars with jet pointed at us One of the most intrinsically bright objects in the universe. Believed to be super massive black holes devouring matter – accelerating it – as it gets sucked into the black hole, gets hot, gives off radiation and part of the material comes out as a jet traveling at a significant fraction of the speed of light. 9 Concepts / themes 1. Very distant colliding galaxies clusters can show • Baryonic or normal matter as light from stars • And dark matter which causes gravitational lensing of distant objects. • They are not in the same spot – because dark matter is not slowed down by interaction with normal matter 2. Quasars and active galactic nuclei (AGN) are supermassive black holes [SMBH] (millions of suns) with an accretion disk and possible jets. SMBH may have formed by collapse of matter at the earliest time of the universe. All galaxies have SMBH at their cores. 3. Distant quasars or blazars used to detect Warm Hot Intergalactic Medium (WHIM) diffuse normal matter that could be part of dark matter SN UDS10Wil – Early Universe – furthest type 1a discovered. 10 NGC 2623 – Merging galaxies, star formation, tidal tails, AGN ~ quasar GRB 150101B – Gamma Ray burst – likely two neutron stars merging like GW170817 JKCS 041 – most distant galaxy cluster – not forming stars Suggests new stars formed from galaxy collisions. MACS J0717.5+3745 -- colliding galaxy cluster lensing mass distribution MACS J1149.5+2223 – Galaxy cluster w lensing & furthest star found Bullet Cluster (1E 0657-56) -colliding galaxy cluster shows evidence of dark matter H1821+643 Quasar used to detect WHIM GOODS-S 29323 – Black hole collapsed directly from gas clouds Very red due to re-emmision of light from disk. H2356-309 Quasar with jet pointed directly at us – evidence of WHIM 3 Quasars 152156.48+520238.5 -- thick disk of gas and dust hides the quasar 153714.26+271611.6 222256.11-094636.2 black hole growing rapidly PSS 0133+0400 PSS 0955+5940 -- very distant quasars, can be used as standard candles to determine distances in the early universe GW151226 – 2nd confirmed gravity wave event M87 – Giant elliptical galaxy in Virgo, AGN with jet, first image of a black hole 3C 273 – First quasar discovered Furthest type 1a supernovae 11 SN UDS10Wil observed by Hubble telescope Redshift, Z, = 1.914 ~3200 Mpc for Ho = 72 km/sec/MPc www.nasa.gov/mission_pages/hubble/science/sn-wilson.html Hubble space telescope image12 NGC 2623 Redshift, Z, = 0.01847 255 mly = 78 MPc Colliding / merging galaxies AGN Represents later star formation due to galaxy collision www.spacetelescope.org/images/potw1742a/ 13 GRB 150101B Gamma Ray Burst or Kilonova Detected Jan 1, 2015 using the Swift Satellite and the Fermi Gamma Ray space telescope. Z= 0.125 (?) Distance = 520 MPc Likely caused by Neutron star merger like that with gravity waves detected https://www.space.com/42158- (GW170817) another-neutron-star-crash- chandra.harvard.edu/photo/2018/kilonova/ detected.html?jwsource=cl 14 JKCS 041 One of the most distant galaxy clusters seen. Z=1.9 ~10 billion L.Y away Star formation in these early galaxies appears to have stopped. Later star formation then caused by colliding galaxies? bib jvno 15 MACS J0717.5+3745 Massive Cluster Survey Large galaxy cluster 5.4 Billion LY away Z~0.545 In Auriga Merger of four galaxy clusters. Hot gas is color coded Mass distribution inferred by lensing of more distant object https://www.spacetelescope.org/images/op o0917a/ 16 MACS J0717.5+3745 Evidence of Dark matter in and around it Map of the likely dark matter around this galaxy cluster show in blue – inferred by gravitational lensing 17 MACS J1149.5+2223 Massive Cluster Survey Galaxy cluster ~5 Billion LY away Redshift, Z, = 0.543 In Leo https://chandra.harvard.edu/photo/2017/macsj1149 18 Gravitational lensing https://www.nasa.gov/content/d iscoveries-highlights-shining- a-light-on-dark-matter • Mass along the line of sight from a distant object will distort the image of the distant object – arcs or multiple images • Used to measure dark matter 19 20 Bullet Cluster (1E 0657-56) Galaxy collision Gravitational lensing in this galaxy is evidence for the existence of dark matter. 3.8 Billion LY Z ~ 0.296 https://chandra.harvard.edu /photo/2006/1e0657/1e065 7_hand.html 21 • Pink is normal matter • Light blue is dark matter measured by gravitational lensing • Offset because normal matter is slowed by interaction with itself • While dark matter was not impeded 22 H1821+643 Quasar in Draco 30 billion solar mass black hole that powers the Quasar Z=0.297 3.4 billion LY Absorption of light by intervening warm hot intergalactic medium (WHIM) 23 GOODS-S 29323 Likely example of where a supermassive black hole was created by the condensation/ collapse of gas Great Observatories Origins Deep Survey … Cluster of galaxies around supermassive black hole Z >~ 6 – very early ~ 500 million years after the big bang(!) https://chandra.harvard.edu/photo/2016/bhseeds/ 24 GOODS consists of data from the following space-based observatories: • The Hubble Space Telescope (optical imaging with the Advanced Camera for Surveys) • The Spitzer Space Telescope (infrared imaging) • The Chandra X-Ray Observatory (X-ray) • XMM-Newton (an X-ray telescope belonging to the European Space Agency) • The Herschel Space Observatory (an infrared telescope belonging to the ESA) 25 H2356-309 Active Galactic Nuclei or Blazar Growing supermassive black hole X-ray light from a Quasar passing through a wall of galaxies (“Sculptor Wall”) Absorption from warm-hot intergalactic media (WHIM) ➔ missing matter Redshift, Z, = 0.165 613 MPc (2 Billion LY) https://chandra.harvard.edu/photo/2010/h2356 26 Sculptor wall (blue line) Direction of Quasar – red dotted line 27 Quasar 152156.48+520238.5 Observed in Xray (Chandra) Quasar 153714.26+271611.6 Rapidly consuming matter Quasar 222256.11-094636.2 through an “accretion disk” Outer cavities that obscures the light from the black hole. X-rays get out. Inner cavities https://chandra.harvard.edu/photo/2015/3quasars// 28 PSS 0955+5940 One of two most distance quasars observed Quasars as “standard candles” https://arxiv.org/pdf/1712.07515.pdf 29 30 GW151226 Gravitational wave signal resulting in a 20.8 sun mass black hole Gravity waves 31 https://www.ligo.caltech.edu/page/what-is-interferometer 32 https://www.ligo.caltech.edu/page/press-release-gw170817 https://www.youtube.com/watch?time_continue=1&v=4X1j2b2atGM Net mass loss in black hole 33 mergers • When lack holes merge they give off a tremendous amount of energy as a result of producing gravity waves. • The energy from producing these energy waves comes from conversion of the mass of the black hole to energy • E=mc2 • The amount of mass lost observed by Ligo is ~3 solar masses(!) https://physicstoday.scitation.org/d oi/full/10.1063/PT.3.1294 34 M87 35 M87 36 M87 Close up of Jet • Z (redshift) = 0.00428 • ~ 16.4 Mpc • Relatively close by • ~53 million light years away 37 M87 Event Horizon telescope view of the core of M87 First supermassive black hole to be imaged (at least its event horizon) 38 M87 39 3C 273 https://chandra.harvard.edu/xray_sources/3c273/i ndex.html One of the first quasars ever detected. 40 41 Remnant radiation let over from the early in the universe – VERY uniform across the sky. Very slight variations (below) is an indication of slight initial variations in the universe that lead to large scale structures The Sculpture wall is an example (H2356-309) of a large scale structure Microwave background Brightness of Stars • Brightness measured as luminosity or magnitude – Luminosity is the total energy output of a star • Depends on size and surface temperature • Usually measure relative to our sun, e.g., 4 times our sun.