1. Alchemy of The Heavens Lecture Eight, Feb. 3, 2003 View, low in the East, early in the morning of July 5, 1054 shows the Crab Supernova

3. Columbia’s Final Flight 8:53 a.m. Shuttle had just 8:53 a.m. Shuttle had just completed a roll reversal, completed a roll reversal, a procedure to bleed a procedure to bleed energy before landing. energy before landing. Four left wing temperature Four left wing temperature sensor readings in the sensor readings in the hydraulic system hydraulic system suddenly were lost. suddenly were lost. 8:56 a.m. Sensors in 8:56 a.m. Sensors in main left wheel well failed, main left wheel well failed, and tire temperatures and tire temperatures were not available. Shuttle were not available. Shuttle was performing well was performing well otherwise. otherwise. 8:58 a.m. Three left wing temperature sensor readings are lost. Because sensors are independent and not linked to a common avionics box, Mission Control becomes concerned. 8:59 a.m. Eight tire temperature and pressure readings are lost. An on board alert message is sent to the crew. In their last transmission, crew members said they had received the alert. 9 a.m. All communication with the shuttle is lost.

4. Alchemy of The Heavens How did God make the chemical elements? How did God make the chemical elements? Chemical element has atomic number Z (number of electrons orbiting nucleus). Chemical element has atomic number Z (number of electrons orbiting nucleus). Chemical reactions do not change the # or type of atomic nuclei. Many alchemists tried and failed to convert Lead (Z=82) into Gold (Z=79). Chemical reactions do not change the # or type of atomic nuclei. Many alchemists tried and failed to convert Lead (Z=82) into Gold (Z=79).

5. Big Bang Nucleosynthesis Nucleosynthesis: origin of the atomic nuclei, (which capture electrons to form chemical elements). Nucleosynthesis: origin of the atomic nuclei, (which capture electrons to form chemical elements). Nuclei are made of protons and neutrons. These particles have similar mass but only protons have an electric charge. Nuclei are made of protons and neutrons. These particles have similar mass but only protons have an electric charge. Protons and neutrons are each made of three quarks. Protons and neutrons are each made of three quarks. By about 3 min. after Big Bang all of the neutrons are bound into 4 He nuclei which have two protons (Helium has Z=2) and 2 neutrons. By about 3 min. after Big Bang all of the neutrons are bound into 4 He nuclei which have two protons (Helium has Z=2) and 2 neutrons. Remaining protons are free to form Hydrogen (Z=1). Remaining protons are free to form Hydrogen (Z=1). Thus Universe was about 25% He and 75% H and little heavier elements (those with Z>2). Thus Universe was about 25% He and 75% H and little heavier elements (those with Z>2).

6. Early Stars First generation stars were made out of only H and He. First generation stars were made out of only H and He. Even if they had planets there was no Si (Z=14) for rocks, no O (Z=8) for H 2 O and no C (Z=6) for life. Planets would be gas balls like our gas giants. Even if they had planets there was no Si (Z=14) for rocks, no O (Z=8) for H 2 O and no C (Z=6) for life. Planets would be gas balls like our gas giants. Need to make these elements with nuclear reactions in first generation stars. Need to make these elements with nuclear reactions in first generation stars. There could not be rocky planets like Jupiter’s Moons (above) but only gas balls like Jupiter (below).

7. Nuclear Reactions Can make new nuclei. Can make new nuclei. However, nuclei are normally kept apart by strong electric repulsion. However, nuclei are normally kept apart by strong electric repulsion. Need great heat and or density to overcome this repulsion and allow nuclear rxns. Need great heat and or density to overcome this repulsion and allow nuclear rxns. These extreme conditions are reached in the center of normal stars. These extreme conditions are reached in the center of normal stars.

8. How to get new elements out? Problem, nuclear rxns, in general, only take place deep within a star. Thus the new elements are locked deep in the stars core. Problem, nuclear rxns, in general, only take place deep within a star. Thus the new elements are locked deep in the stars core. How to get the elements out to form rocky planets and life? How to get the elements out to form rocky planets and life? Answer: Wait for the star to die. Answer: Wait for the star to die.

9. Life of a Star Birth: collapse of gas cloud forms protostar. Birth: collapse of gas cloud forms protostar. Main sequence: center of star becomes hot enough to burn Hydrogen into Helium. Our Sun will be on main sequence for 10 billion years. Main sequence: center of star becomes hot enough to burn Hydrogen into Helium. Our Sun will be on main sequence for 10 billion years. Red Giant: Outer part of star expands and cools. Core contracts and starts to burn He into Carbon and other heavier elements. Red Giant: Outer part of star expands and cools. Core contracts and starts to burn He into Carbon and other heavier elements. Star dies: either as a planetary nebula (low mass star) or as a supernova (high mass star). Star dies: either as a planetary nebula (low mass star) or as a supernova (high mass star).

10. Planetary Nebula Stars with mass less then about 8 times the mass of the Sun die as planetary nebula. Stars with mass less then about 8 times the mass of the Sun die as planetary nebula. Intense stellar wind ejects lots of gas from surface of red giant. Note, Sun has solar wind which is stream of particles from surface. Intense stellar wind ejects lots of gas from surface of red giant. Note, Sun has solar wind which is stream of particles from surface. Note, planetary nebula name has nothing to do with planets. Note, planetary nebula name has nothing to do with planets.

11. Planetary Nebula M27 Image by J. Newton

12. Jack Newton’s House Furniture salesman and amateur astronomer

13. The Universe From My Driveway On the course web site I have added some images taken with a small 8” telescope and a sensitive CCD camera. On the course web site I have added some images taken with a small 8” telescope and a sensitive CCD camera. http://physics.indiana.edu /~life and click on driveway universe. http://physics.indiana.edu /~life and click on driveway universe. http://physics.indiana.edu /~life http://physics.indiana.edu /~life One evening during the class, those interested can observe with me. One evening during the class, those interested can observe with me.

14. Supernova Stars with more then 8 solar masses die in gigantic explosions called supernovae. Note, plural of supernova is supernovae. Stars with more then 8 solar masses die in gigantic explosions called supernovae. Note, plural of supernova is supernovae. A single star that explodes as a supernova can outshine an entire galaxy (billions of stars). A single star that explodes as a supernova can outshine an entire galaxy (billions of stars). Hard to imagine the violence of the explosion. Hard to imagine the violence of the explosion. Core of star imploded to form neutron star or black hole. Core of star imploded to form neutron star or black hole. Outer part of star ejected into space with new chemical elements. Outer part of star ejected into space with new chemical elements.

15. Supernova viewed from my driveway SN1998S in Ngc 3877, April 2, 1998 (8” SCT homemade CCD)

16. A Supernova is very bright Note, foreground stars are typically 100s of light years away. Note, foreground stars are typically 100s of light years away. Galaxy and supernova are ~100 million light years away. Galaxy and supernova are ~100 million light years away. That one can see it at all implies the explosion is very bright. That one can see it at all implies the explosion is very bright.

17. Supernova Simulation Computer simulation by Adam Burrows of a supernova in a binary star system (two stars orbiting each other). Computer simulation by Adam Burrows of a supernova in a binary star system (two stars orbiting each other). You are looking at the 2 nd star which is many times larger then the Earth. The exploding star is just off the top of the screen. You are looking at the 2 nd star which is many times larger then the Earth. The exploding star is just off the top of the screen. Real Video of Burrows Simulation Real Video of Burrows Simulation Real Video of Burrows Simulation Real Video of Burrows Simulation

18. The Crab Supernova Simulation of view early in the morning, July 5, 1054 Moon Supernova

19. Native American Paintings of Crab Well recorded in China, Korea and Middle East but not in Europe (middle ages). Well recorded in China, Korea and Middle East but not in Europe (middle ages).

20. Crab Nebula Today Exploding star has thrown material out into space at about 1/300 speed of light. Exploding star has thrown material out into space at about 1/300 speed of light. In 1000 years nebula is now about 3 light years across. In 1000 years nebula is now about 3 light years across. Nebula enriches interstellar medium with chemical elements. Nebula enriches interstellar medium with chemical elements.

21. Vela: 10000 year old SN Remnant Vela Pulsar

22. Crab pulsar Hubble space telescope image (in visible light) of neutron star (base of arrow) at heart of Crab nebula. Hubble space telescope image (in visible light) of neutron star (base of arrow) at heart of Crab nebula. Neutron star spins 30 times a second and emits pulses of radio waves  pulsar. Neutron star spins 30 times a second and emits pulses of radio waves  pulsar.

23. Neutron Star Collapsed object 1.5 times mass of Sun but only about 10 miles across. It is one gigantic atomic nucleus! Collapsed object 1.5 times mass of Sun but only about 10 miles across. It is one gigantic atomic nucleus! Squeeze all of the empty space out of an atom. Squeeze electrons onto protons to form neutrons. Squeeze all of the empty space out of an atom. Squeeze electrons onto protons to form neutrons. Gives neutron star. Densest form of matter before black hole. Gives neutron star. Densest form of matter before black hole.

24. Supernovae Gigantic stellar explosions. Gigantic stellar explosions. Eject new chemical elements into space. Eject new chemical elements into space. Make neutron stars and black holes. Make neutron stars and black holes. Accelerate cosmic rays (energetic particles constantly hitting Earth’s atmosphere from space). Accelerate cosmic rays (energetic particles constantly hitting Earth’s atmosphere from space). Shock waves can help gas clouds to collapse and form new stars. Shock waves can help gas clouds to collapse and form new stars. Deadly to life (within say ~1-300 light years???) Deadly to life (within say ~1-300 light years???)

25. 2 nd Generation Stars 2 nd generation stars, made from the collapse of a gas cloud enriched in chemical elements, can have rocky planets and perhaps life. 2 nd generation stars, made from the collapse of a gas cloud enriched in chemical elements, can have rocky planets and perhaps life. Sun formed 4.6 Billion years ago. Sun formed 4.6 Billion years ago. Needed 1 st generation stars to be formed, live, and die all before 4.6 Billion years ago. Needed 1 st generation stars to be formed, live, and die all before 4.6 Billion years ago. These provided the Carbon, Oxygen, Nitrogen … of which we are made. These provided the Carbon, Oxygen, Nitrogen … of which we are made. We are literally “star dust”. All of the atoms in our body were made in other stars. We are literally “star dust”. All of the atoms in our body were made in other stars.

26. For next time Read chap. 4 of Jakosky about the earliest life and read “Vital Dust", pages 1-23 in course packet about origin of life. Read chap. 4 of Jakosky about the earliest life and read “Vital Dust", pages 1-23 in course packet about origin of life. Next lecture, Wend Feb 5, 2003, “Formation of Earth”. Next lecture, Wend Feb 5, 2003, “Formation of Earth”.