PPT-Hot Excess around Main Sequence Stars: Statement of the problem and programmatic implications

Statement of the problem and programmatic implications for N ASA Bertrand Mennesson JPL May 20 2015 Outline Brief Review of Observational evidence over the last 10 years Ancillary measurements and . Fall 2014. . Lecture11; November 13, 2014. Tonight!. Astro. 1 Observing Session (Optional, Just for Fun). WHEN: November 13. th. at 7-9pm . Same time Nov. 20. th. if the 13. th. is cloudy. WHERE: . A little bit on its . metallicity. (. Z. ). Sometimes influenced by nearby stars. Low mass stars (. M < . 8. M. Sun. ) live a long life and die slowly. High mass stars (. M. > 8. M. Sun. ) live fast and die violently. B-V color index way of quantifying this - determining spectral class - using two different filters. one a blue (B) filter that only lets a narrow range of colors or wavelengths through centered on the blue colors, . of Low-mass . Stars. After birth, newborn stars are very large, so they are very bright. Gravity causes them to contract, and they become fainter because of their smaller sizes.. After contracting for millions of years, stars eventually become hot enough to fuse hydrogen, which halts their contraction. They now maintain a stable size and luminosity until they run out of hydrogen fuel. This is the . PROTOSTAR. Region of . gas. and . dust . create a nebula. Gravity . causes the gas and dust to condense creating a . protostar. The prefix “proto” means . first. or . original. A . How big are stars?. How far . away?. How . luminous?. How hot?. How old, and how much longer to . live?. C. hemical . composition?. How are they moving?. Are they isolated or in clusters?. 1. How Far Away are the Stars?. The main sequence. Evolution off the main sequence. Nucleosynthesis. PHY111. Stellar Evolution and . Nucleosynthesis. Basics. On the . Hertzsprung. -Russell Diagram. Observations. Evolution on to the Main Sequence. HR-Diagram- What is it?. Stands for the . Hertzsprung. -Russell Diagram. Graphs surface temperature (color) vs. Absolute Brightness (Luminosity). Horizontal Axis- Surface Temp/Color. Vertical Axis- Absolute Brightness . . Objective:. I can outline the life cycle of a star.. Honors HW. : Work on your check off sheet. Turn in all missing assignments so you can go to reward day Thursday!! . H - Tuesday, May 8, 2012. Chapter 2 Review of Literature This chapter serves as the foundation on which the study is built and as a basis for tions It summarizes what isrtation study The more extensive the previous work the th. Grade. This is a Hubble Heritage image of Sagittarius Star field. From left to right the image is 13.3 light-years across. What do you notice by looking at this image? . From the picture you should have noticed that stars have _______________.The different colors indicate the __________________ of a star.. PowerPoint Created by: Alexander J. Hawkins. Information documented from . DK Smithsonian UNIVERSE Definitive Visual Guide. Stellar Life. As human beings go through cyclic lives, maturing from birth to maturity to old age, stars also follow a series of stages from their creation until death. Stars follow varying sequences of change depending greatly on their solar mass, or their gravitational weight . A . star is a massive ball of plasma that emits . light and electromagnetic energy . throughout the universe. . While . there is only one star in our solar system, there are billions upon billions of stars throughout our galaxy and exponentially more in the billions of galaxies in the universe. Stage 1. Stage 3. Stage 2. Stage. 1. Stage. . 2. Stage 3. Main sequence stage, last. the longest. Star stays until all H. 2 . fuel . is used up (converted to He). He core shrinks and . Contracts to produce .