Chapter 17 Measuring the Stars
... Measuring Stellar Masses in Binary Stars In order to measure stellar masses in a binary star, the period and semimajor axis of the orbit must be measured. Once this is done, Kepler’s third law gives the sum of the masses of the two stars. Then the relative speeds of the two stars can be measured usi ...
... Measuring Stellar Masses in Binary Stars In order to measure stellar masses in a binary star, the period and semimajor axis of the orbit must be measured. Once this is done, Kepler’s third law gives the sum of the masses of the two stars. Then the relative speeds of the two stars can be measured usi ...
Stars, Galaxies, and the Universe Section 1
... much light the star emits and how far the star is from Earth. • Absolute magnitude the brightness that a star would have at a distance of 32.6 light-years from Earth • The brighter a star is, the lower the number of its ...
... much light the star emits and how far the star is from Earth. • Absolute magnitude the brightness that a star would have at a distance of 32.6 light-years from Earth • The brighter a star is, the lower the number of its ...
26.4 Groups of Stars
... How are stars distributed in space? Astronomers have determined that more than half of all stars are members of star systems. ...
... How are stars distributed in space? Astronomers have determined that more than half of all stars are members of star systems. ...
Summary Of the Structure of the Milky Way
... has yielded the orbital speed of the Sun as it orbits the galactic center and the age of the Milky Way. • Finally, when knowledge of the orbital speed of Sun is combined with its distance from the galactic center an estimate of the mass of the galaxy can be obtained. ...
... has yielded the orbital speed of the Sun as it orbits the galactic center and the age of the Milky Way. • Finally, when knowledge of the orbital speed of Sun is combined with its distance from the galactic center an estimate of the mass of the galaxy can be obtained. ...
Light and shadow from distant worlds
... discovered two planets comparable to Neptune in size20,21, and one super-Earth only 70% larger in radius than our own Earth22. The recent launch of NASA’s Kepler mission23 will greatly increase the number of rocky and/or icy transiting planets known. Most exciting is that Kepler is designed to tell ...
... discovered two planets comparable to Neptune in size20,21, and one super-Earth only 70% larger in radius than our own Earth22. The recent launch of NASA’s Kepler mission23 will greatly increase the number of rocky and/or icy transiting planets known. Most exciting is that Kepler is designed to tell ...
The Mt John University Observatory search for Earth
... within 50 years. The α Centauri binary consists of a G2V primary (HR 5459, HD 128620, V = − 0.01) and a K1V secondary (HR 5460, HD 128621, V = 1.33) moving in an eccentric (e = 0.518) orbit with a semi-major axis of a = 23 AU and a period of almost 80 years (Heintz 1982; Pourbaix et al. 1999). The p ...
... within 50 years. The α Centauri binary consists of a G2V primary (HR 5459, HD 128620, V = − 0.01) and a K1V secondary (HR 5460, HD 128621, V = 1.33) moving in an eccentric (e = 0.518) orbit with a semi-major axis of a = 23 AU and a period of almost 80 years (Heintz 1982; Pourbaix et al. 1999). The p ...
Volume 2 - Euresis Journal
... opened the floodgates on extrasolar planet discoveries, with over 700 found to date, and the number rapidly growing. Let us review the various techniques that have made it possible, after more than 400 years, to confirm Bruno’s planetary conjecture. ...
... opened the floodgates on extrasolar planet discoveries, with over 700 found to date, and the number rapidly growing. Let us review the various techniques that have made it possible, after more than 400 years, to confirm Bruno’s planetary conjecture. ...
Discovery of the First Eclipsing Binary Barium Star
... characteristics of these systems. However, the relatiJely Large orbital separation (estimated as sevef8l AU) and the low lumlnos'ty of the companion (dictated by the SB1 nature of the system) Imply that photomettlc variations, if present, should b of rather small amplitude and have a long period. La ...
... characteristics of these systems. However, the relatiJely Large orbital separation (estimated as sevef8l AU) and the low lumlnos'ty of the companion (dictated by the SB1 nature of the system) Imply that photomettlc variations, if present, should b of rather small amplitude and have a long period. La ...
Lecture
... where nuclear fusion in their cores produces most of their energies. • It is possible to calculate an approximate star’s lifetime by determining its mass (tlife ~ 1/M2.5) • Cold (red ones) stars have longer lifetime than hot stars: – O star: ~ 1 million years – G star (Sun): ~ 10 billion years – M s ...
... where nuclear fusion in their cores produces most of their energies. • It is possible to calculate an approximate star’s lifetime by determining its mass (tlife ~ 1/M2.5) • Cold (red ones) stars have longer lifetime than hot stars: – O star: ~ 1 million years – G star (Sun): ~ 10 billion years – M s ...
Dynamics of elliptical galaxies
... Classification of stellar orbits in elliptical galaxies is much more complicated than for disk galaxies. Most important distinction is between axisymmetric galaxies (prolate or oblate) and triaxial galaxies. In an axisymmetric galaxy, there is a plane, perpendicular to the symmetry axis, in which gr ...
... Classification of stellar orbits in elliptical galaxies is much more complicated than for disk galaxies. Most important distinction is between axisymmetric galaxies (prolate or oblate) and triaxial galaxies. In an axisymmetric galaxy, there is a plane, perpendicular to the symmetry axis, in which gr ...
ExTRaSOLaR pLaNeTS
... The Optical Gravitational Lensing Experiment (OGLE) located at Las Campanas, Chile, was used to find the first planet through ...
... The Optical Gravitational Lensing Experiment (OGLE) located at Las Campanas, Chile, was used to find the first planet through ...
No Slide Title
... can also reveal the presence of planets through anomalous timings of the expected eclipses – A good example is the close eclipsing white dwarf + red dwarfs binary NN Ser, which appears to have 2 Jupiter mass planets ...
... can also reveal the presence of planets through anomalous timings of the expected eclipses – A good example is the close eclipsing white dwarf + red dwarfs binary NN Ser, which appears to have 2 Jupiter mass planets ...
The Cosmic Perspective Other Planetary Systems: The New Science
... so close to their stars? a) The nebular theory has been modified to allow for the formation of gas giant planets close to a star. b) The hot Jupiters are close to cool stars, and so are not actually very hot and have the same history as gas giants in our solar system. c) These gas giants formed f ...
... so close to their stars? a) The nebular theory has been modified to allow for the formation of gas giant planets close to a star. b) The hot Jupiters are close to cool stars, and so are not actually very hot and have the same history as gas giants in our solar system. c) These gas giants formed f ...
Science Across Disciplines
... The discovery of extra-solar planets is one of the greatest achievements of modern astronomy. There are now more than two hundred such objects known, and the recent detection of planets with masses approximately 5 times that of Earth demonstrates that extra-solar planets of low mass exist. In additi ...
... The discovery of extra-solar planets is one of the greatest achievements of modern astronomy. There are now more than two hundred such objects known, and the recent detection of planets with masses approximately 5 times that of Earth demonstrates that extra-solar planets of low mass exist. In additi ...
to access chapter 16
... Temperature of Stars The Sun is the closest star to Earth. It is by far the brightest star in the sky. It’s easy to think that the stars that look the brightest are the closest. However, Barnard’s Star is the third closest to Earth, but it can’t be seen without a telescope. So just what is it that m ...
... Temperature of Stars The Sun is the closest star to Earth. It is by far the brightest star in the sky. It’s easy to think that the stars that look the brightest are the closest. However, Barnard’s Star is the third closest to Earth, but it can’t be seen without a telescope. So just what is it that m ...
Stellar Populations of Galaxies- 2 Lectures H
... Classical indicators of what is going on: The limit of the Balmer series and the blending of the high-order Balmer lines produces a discontinuity of the spectrum blueward of 3650°A. (the Balmer break) –more important in young populations, The break amplitude and position is a proxy for the age of th ...
... Classical indicators of what is going on: The limit of the Balmer series and the blending of the high-order Balmer lines produces a discontinuity of the spectrum blueward of 3650°A. (the Balmer break) –more important in young populations, The break amplitude and position is a proxy for the age of th ...
PH607lec12
... through the process of fusion. These metals were spewed into the galactic medium through stellar winds and supernova explosions and became part of the disc. This means that the stars in the disc formed out of metal rich material. This process is known as the "Outside-In" theory. ...
... through the process of fusion. These metals were spewed into the galactic medium through stellar winds and supernova explosions and became part of the disc. This means that the stars in the disc formed out of metal rich material. This process is known as the "Outside-In" theory. ...
Extra-solar planets
... However, we can detect velocities very easily, because of the Doppler shift. As the star wobbles to and fro, we see lines in its spectrum moving first to the red, and then to the blue. Measuring the size of this shift allows us to determine the velocity of the star, and hence (from Kepler’s law) th ...
... However, we can detect velocities very easily, because of the Doppler shift. As the star wobbles to and fro, we see lines in its spectrum moving first to the red, and then to the blue. Measuring the size of this shift allows us to determine the velocity of the star, and hence (from Kepler’s law) th ...
Hubble Deep Field Image
... Could not contain very bright objects or anything that emitted too much infrared, x-ray, or UV In addition, field could never be occulted by the Earth or Moon. ...
... Could not contain very bright objects or anything that emitted too much infrared, x-ray, or UV In addition, field could never be occulted by the Earth or Moon. ...
Seeing another Earth: Detecting and Characterizing Rocky Planets
... formation of Mars-mass or Earth-mass planets. These results suggest that we will eventually find a planetary system similar to our own. Today, exoplanet research is in the midst of a transition from discovery to analysis and understanding. Measurements of the mass-radius relation derived from transi ...
... formation of Mars-mass or Earth-mass planets. These results suggest that we will eventually find a planetary system similar to our own. Today, exoplanet research is in the midst of a transition from discovery to analysis and understanding. Measurements of the mass-radius relation derived from transi ...
High-Speed Ballistic Stellar Interlopers
... approach between two binary star systems—or a binary system and a third star. In such cases, one or more of the stars can pick up enough energy through gravitational interaction with the others to be thrown from the system. Determining how many stars have been ejected from their neighbors is importa ...
... approach between two binary star systems—or a binary system and a third star. In such cases, one or more of the stars can pick up enough energy through gravitational interaction with the others to be thrown from the system. Determining how many stars have been ejected from their neighbors is importa ...
I Cloudy with a Chance of Making a star is no easy thing
... Charles Lada of the Harvard-Smithsonian Center for Astrophysics (CfA), João Alves of the European Southern Observatory (ESO) and their co-workers have argued for the slow dissipation of thermal support. By mapping molecular clouds at millimeter and submillimeter wavelengths, which straddle the radio ...
... Charles Lada of the Harvard-Smithsonian Center for Astrophysics (CfA), João Alves of the European Southern Observatory (ESO) and their co-workers have argued for the slow dissipation of thermal support. By mapping molecular clouds at millimeter and submillimeter wavelengths, which straddle the radio ...
The Intricate Role of Cold Gas and Dust in Galaxy Evolution at Early
... Almost as many stars as the Milky Way! Similar total mass, already at z=6.34! 40x more gas! 2000x more star formation! …and ~20x more star formation ! than extreme nearby starburst! ...
... Almost as many stars as the Milky Way! Similar total mass, already at z=6.34! 40x more gas! 2000x more star formation! …and ~20x more star formation ! than extreme nearby starburst! ...
DAS FOCUS Newsletter_MARCH_2015
... It’s hard for me to accept that it’s been over 4 months since I had my 18” scope out for observing. The Trap Pond State Park session with the Delmarva Stargazers on October 25 was my last time out. Spolier alert: I’m going to complain about the weather. Last year at this time many were observing the ...
... It’s hard for me to accept that it’s been over 4 months since I had my 18” scope out for observing. The Trap Pond State Park session with the Delmarva Stargazers on October 25 was my last time out. Spolier alert: I’m going to complain about the weather. Last year at this time many were observing the ...
Space Interferometry Mission
The Space Interferometry Mission, or SIM, also known as SIM Lite (formerly known as SIM PlanetQuest), was a planned space telescope developed by the U.S. National Aeronautics and Space Administration (NASA), in conjunction with contractor Northrop Grumman. One of the main goals of the mission was the hunt for Earth-sized planets orbiting in the habitable zones of nearby stars other than the Sun. SIM was postponed several times and finally cancelled in 2010.In addition to hunting for extrasolar planets, SIM would have helped astronomers construct a map of the Milky Way galaxy. Other important tasks would have included collecting data to help pinpoint stellar masses for specific types of stars, assisting in the determination of the spatial distribution of dark matter in the Milky Way and in the Local Group of galaxies and using the gravitational microlensing effect to measure the mass of stars.The spacecraft would have used optical interferometry to accomplish these and other scientific goals. This technique collects light with multiple mirrors (in SIM's case, two) which is combined to make an interference pattern which can be very precisely measured.The initial contracts for SIM Lite were awarded in 1998, totaling US$200 million. Work on the SIM project required scientists and engineers to move through eight specific new technology milestones, and by November 2006, all eight had been completed.SIM Lite was originally scheduled for a 2005 launch, aboard an Evolved Expendable Launch Vehicle (EELV). As a result of continued budget cuts, the launch date has been pushed back at least five times. NASA has set a preliminary launch date for 2015 and U.S. federal budget documents confirm that a launch date is expected ""no earlier"" than 2015. The budget cuts to SIM Lite are expected to continue through FY 2010. As of February 2007, many of the engineers working on the SIM program had moved on to other areas and projects, and NASA directed the project to allocate its resources toward engineering risk reduction. However, the preliminary budget for NASA for 2008 included zero dollars for SIM.In December 2007, the Congress restored funding for fiscal year 2008 as part of an omnibus appropriations bill which the President later signed. At the same time the Congress directed NASA to move the mission forward to the development phase. In 2009 the project continued its risk reduction work while waiting for the findings and recommendations of the Astronomy and Astrophysics Decadal Survey, Astro2010, performed by the National Academy of Sciences, which would determine the project's future.On 13 August 2010, the Astro2010 Decadal Report was released and did not recommend that NASA continue the development of the SIM Lite Astrometric Observatory. This prompted NASA Astronomy and Physics Director, Jon Morse, to issue a letter on 24 September 2010 to the SIM Lite project manager, informing him that NASA was discontinuing its sponsorship of the SIM Lite mission and directing the project to discontinue Phase B activities immediately or as soon as practical. Accordingly, all SIM Lite activities were closed down by the end of calendar year 2010.