Stars, Galaxies, and the Universe Section 1
... barycenter, is somewhere between the two stars. • In star systems that have more than two stars, two stars may revolve rapidly around a common barycenter, while a third star revolves more slowly at a greater distance from the pair. • Astronomers estimate that more than half of all sunlike stars are ...
... barycenter, is somewhere between the two stars. • In star systems that have more than two stars, two stars may revolve rapidly around a common barycenter, while a third star revolves more slowly at a greater distance from the pair. • Astronomers estimate that more than half of all sunlike stars are ...
Stars and the Milky Way
... • we live in a galaxy called the Milky Way • the Milky Way is one of billions of galaxies in the universe • the Milky Way is made up of over 200 billion stars Other facts about the Milky Way • The Sun is just one of the stars in the Milky Way. • It is called the Milky Way because when astronomers lo ...
... • we live in a galaxy called the Milky Way • the Milky Way is one of billions of galaxies in the universe • the Milky Way is made up of over 200 billion stars Other facts about the Milky Way • The Sun is just one of the stars in the Milky Way. • It is called the Milky Way because when astronomers lo ...
... Mauray, using CCD astrometry and Mason, using speckle interferometry. Both points are single measurements. This example highlights the need for many more high quality observations, which will also contribute to a better understanding of different modern observational methods. Mathieu – Velocities of ...
The Detection and Characterization of Extrasolar Planets
... Given that planets are typically close to a star that is much more luminous than the planet, direct detection of exoplanets is extremely difficult. This means that most confirmed exoplanets have been detected indirectly. There are a number of different indirect methods. One, known as the ‘Doppler wo ...
... Given that planets are typically close to a star that is much more luminous than the planet, direct detection of exoplanets is extremely difficult. This means that most confirmed exoplanets have been detected indirectly. There are a number of different indirect methods. One, known as the ‘Doppler wo ...
mufon ufo symposium -1974
... F5V to F7V have more stars rotating slowly indicating the possibility of planets. From approximately F8 on, all main sequence stars are rotating slowly, probably indicating planets. According to Carl Sagan, F8 is the point where intelligent life would have time to emerge. So main sequence stars fro ...
... F5V to F7V have more stars rotating slowly indicating the possibility of planets. From approximately F8 on, all main sequence stars are rotating slowly, probably indicating planets. According to Carl Sagan, F8 is the point where intelligent life would have time to emerge. So main sequence stars fro ...
Tasks - ESA Science
... Astronomy is an accessible and visual science, making it ideal for educational purposes. Over the last few years the NASA/ESA Hubble Space Telescope and the ESO telescopes at the La Silla and Paranal Observatories in Chile have presented ever deeper and more spectacular views of the Universe. Howeve ...
... Astronomy is an accessible and visual science, making it ideal for educational purposes. Over the last few years the NASA/ESA Hubble Space Telescope and the ESO telescopes at the La Silla and Paranal Observatories in Chile have presented ever deeper and more spectacular views of the Universe. Howeve ...
exemplars and commentary
... Red dwarfs are often covered by starspots, reducing stellar output by as much as 40% for months at a time. At other times, some red dwarfs, called flare stars, can emit gigantic flares, doubling their brightness in minutes. These are the result of the convection currents .Barnard’s star was thought ...
... Red dwarfs are often covered by starspots, reducing stellar output by as much as 40% for months at a time. At other times, some red dwarfs, called flare stars, can emit gigantic flares, doubling their brightness in minutes. These are the result of the convection currents .Barnard’s star was thought ...
Project Icarus: Astronomical Considerations Relating to the Choice
... Within 15 light-years of the Sun there are approximately 56 stars, in 38 separate stellar systems. The number is approximate for several reasons. Firstly, at the outer boundary the errors on the distances can amount to a few tenths of a light-year, which could mean that some stars notionally just be ...
... Within 15 light-years of the Sun there are approximately 56 stars, in 38 separate stellar systems. The number is approximate for several reasons. Firstly, at the outer boundary the errors on the distances can amount to a few tenths of a light-year, which could mean that some stars notionally just be ...
On the correlation between stellar chromospheric flux and the
... field with an azimuthal flux rope encircling the star. The green solid lines are the field lines of the stellar coronal field, the orange dot is a close-in planet from which matter can evaporate and, after moving towards the star along the field lines, condense in the potential well to form a promin ...
... field with an azimuthal flux rope encircling the star. The green solid lines are the field lines of the stellar coronal field, the orange dot is a close-in planet from which matter can evaporate and, after moving towards the star along the field lines, condense in the potential well to form a promin ...
THE MONTHLY SKY GUIDE, SIXTH EDITION
... Most bright stars, and several not-so-bright ones, have strangesounding names. Other stars are known merely by letters and numbers. These designations arose in various ways, as follows. A number of star names date back to Greek and Roman times. For example, the name of the brightest star in the sky, ...
... Most bright stars, and several not-so-bright ones, have strangesounding names. Other stars are known merely by letters and numbers. These designations arose in various ways, as follows. A number of star names date back to Greek and Roman times. For example, the name of the brightest star in the sky, ...
The Milky Way and Its Neighbors
... 2)Mapping HII regions via Hα emission lines - HII regions trace active star formation Old data showed that there were 4 arms New data from Spitzer indicates that there are only 2 major spiral arms: -Scutum and Perseus Arms ...
... 2)Mapping HII regions via Hα emission lines - HII regions trace active star formation Old data showed that there were 4 arms New data from Spitzer indicates that there are only 2 major spiral arms: -Scutum and Perseus Arms ...
Fomalhaut b
... • 1984 : IRAS mission finds dust grains orbi)ng Fomalhaut, as well as other stars such as Epsilon Eridani, Vega, and Beta Pictoris • Resolved thermal emission shows a central hole (Holland et al. 1998) • Fomalhaut is nearby (7.7 pc). High proper mo)on (0.4”/yr). • Fomalhaut is a young, ma ...
... • 1984 : IRAS mission finds dust grains orbi)ng Fomalhaut, as well as other stars such as Epsilon Eridani, Vega, and Beta Pictoris • Resolved thermal emission shows a central hole (Holland et al. 1998) • Fomalhaut is nearby (7.7 pc). High proper mo)on (0.4”/yr). • Fomalhaut is a young, ma ...
Star Formation in the Galaxy, An Observational Overview
... on to their outer atmospheres. Once a star exhausts its supply of hydrogen in its central core, nuclear reactions there plummet and the helium-rich core contracts unable to support itself against gravity. The contraction of the core releases large amounts of gravitational potential energy that cause ...
... on to their outer atmospheres. Once a star exhausts its supply of hydrogen in its central core, nuclear reactions there plummet and the helium-rich core contracts unable to support itself against gravity. The contraction of the core releases large amounts of gravitational potential energy that cause ...
Lecture18
... Some stars hot but faint, or cool but very bright: Stars not on the main sequence: giants and super-giants, white dwarfs (all late phases in a star’s lifetime). “Luminosity class” used to distinguish a red main sequence (e.g. M5V) from a red supergiant (M5I). Sizes of stars vary tremendously: White ...
... Some stars hot but faint, or cool but very bright: Stars not on the main sequence: giants and super-giants, white dwarfs (all late phases in a star’s lifetime). “Luminosity class” used to distinguish a red main sequence (e.g. M5V) from a red supergiant (M5I). Sizes of stars vary tremendously: White ...
Spectral Classification: The First Step in Quantitative Spectral Analysis
... Spectral Analysis begins with the estimation of the physical parameters: Teff, log(g), [M/H]. How can Spectral Classification help? • Spectral classification in conjunction with photometry is the best way to determine the interstellar reddening because it does not depend on an extinction model. • C ...
... Spectral Analysis begins with the estimation of the physical parameters: Teff, log(g), [M/H]. How can Spectral Classification help? • Spectral classification in conjunction with photometry is the best way to determine the interstellar reddening because it does not depend on an extinction model. • C ...
Lyra
Lyra (/ˈlaɪərə/; Latin for lyre, from Greek λύρα) is a small constellation. It is one of 48 listed by the 2nd century astronomer Ptolemy, and is one of the 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence sometimes referred to as Aquila Cadens or Vultur Cadens. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is visible from the northern hemisphere from spring through autumn, and nearly overhead, in temperate latitudes, during the summer months. From the southern hemisphere, it is visible low in the northern sky during the winter months.The lucida or brightest star—and one of the brightest stars in the sky—is the white main sequence star Vega, a corner of the Summer Triangle. Beta Lyrae is the prototype of a class of stars known as Beta Lyrae variables, binary stars so close to each other that they become egg-shaped and material flows from one to the other. Epsilon Lyrae, known informally as the Double Double, is a complex multiple star system. Lyra also hosts the Ring Nebula, the second-discovered and best-known planetary nebula.