Detection of Earth-impacting asteroids with the next generation all
... changes have serious consequences for the survival and evolution of life on the planet. But in the past ∼50 years more than 170 impact structures have been identified on the surface of the Earth (Earth-impact database 2008). Were it not for the Earth’s protective atmosphere, oceans, erosion and plat ...
... changes have serious consequences for the survival and evolution of life on the planet. But in the past ∼50 years more than 170 impact structures have been identified on the surface of the Earth (Earth-impact database 2008). Were it not for the Earth’s protective atmosphere, oceans, erosion and plat ...
Galaxy Evolution
... has been shown that such ideas were incorrect, nonetheless the nomenclature has remained, and today it is common, for example, to refer to ellipticals and lenticulars as ‘earlytype galaxies’. The luminosity function One very powerful tool that describes in a quantitative way two of the most importan ...
... has been shown that such ideas were incorrect, nonetheless the nomenclature has remained, and today it is common, for example, to refer to ellipticals and lenticulars as ‘earlytype galaxies’. The luminosity function One very powerful tool that describes in a quantitative way two of the most importan ...
Gas fraction and star formation efficiency at z< 1.0
... 1) at redshifts between 0.6 < z < 1.0. The sources have been selected based on their 60 µm flux from IRAS, or 70 µm flux from Spitzer-MIPS. The open histogram indicates COundetected sources, while the filled histogram shows detections. 12.45, between 0.6 < z < 1, with a declination greater than 12◦ ...
... 1) at redshifts between 0.6 < z < 1.0. The sources have been selected based on their 60 µm flux from IRAS, or 70 µm flux from Spitzer-MIPS. The open histogram indicates COundetected sources, while the filled histogram shows detections. 12.45, between 0.6 < z < 1, with a declination greater than 12◦ ...
Aries The Ram - Maverick`s E-portfolio
... The constellation of Aries has been home to many legends. Sumerians in Mesopotamia were enthralled by a bright star residing in the constellation of Aries known as Hamal. Sumerians believed that Hamal, which means the lamb, was one of the stars in the Scimitar. They believed that the Scimitar was a ...
... The constellation of Aries has been home to many legends. Sumerians in Mesopotamia were enthralled by a bright star residing in the constellation of Aries known as Hamal. Sumerians believed that Hamal, which means the lamb, was one of the stars in the Scimitar. They believed that the Scimitar was a ...
Near-Earth Objects - The Koschny Family
... sun with a pericenter distance of less than 1.3 AU. If the cross the path of the Earth in the orbit around the sun, they pose a threat to our planet. An object with about 40 m diameter exploded in the atmosphere above the Siberian Tunguska area in 1908 and flattened >2000 km2 of forest. Had this obj ...
... sun with a pericenter distance of less than 1.3 AU. If the cross the path of the Earth in the orbit around the sun, they pose a threat to our planet. An object with about 40 m diameter exploded in the atmosphere above the Siberian Tunguska area in 1908 and flattened >2000 km2 of forest. Had this obj ...
Part 9: Story of the Universe
... • It also defines Keplerian Velocity. In order for an object to remain in stable revolution around a star, it must have a velocity so that gravity and centrifugal force are balanced. • The inverse square law implies that in general, the orbit of an object experiencing the gravitational attraction of ...
... • It also defines Keplerian Velocity. In order for an object to remain in stable revolution around a star, it must have a velocity so that gravity and centrifugal force are balanced. • The inverse square law implies that in general, the orbit of an object experiencing the gravitational attraction of ...
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... To derive absolute K-magnitudes, we used the logP− K relations from Ita et al. (1994). For stars classified as Miras we used Ita’s relation C including their separation for targets with J − K < 1.4 and J − K > 1.4. For semi-regular variables we used sequence B or C’. Naturally, this approach include ...
... To derive absolute K-magnitudes, we used the logP− K relations from Ita et al. (1994). For stars classified as Miras we used Ita’s relation C including their separation for targets with J − K < 1.4 and J − K > 1.4. For semi-regular variables we used sequence B or C’. Naturally, this approach include ...
Galaxies
... Classifying Galaxies • Spiral galaxies are denoted by “S”, and barred spirals by “SB”. Letters “a”, “b”, “c” denote how tightly the spiral arms are wound, with “a” being most tightly wound. The Andromeda Galaxy is an Sb. • Elliptical galaxies are denoted by “E”, with a number from 0-7 indicating ho ...
... Classifying Galaxies • Spiral galaxies are denoted by “S”, and barred spirals by “SB”. Letters “a”, “b”, “c” denote how tightly the spiral arms are wound, with “a” being most tightly wound. The Andromeda Galaxy is an Sb. • Elliptical galaxies are denoted by “E”, with a number from 0-7 indicating ho ...
hr diagrams of star clusters
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
THE PERIOD OF ROTATION OF THE SUN
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
Chapter 16--Properties of Stars
... stars form in great clouds of gas and dust. Each star begins its life with roughly the same chemical composition: About three-quarters of the star’s mass at birth is hydrogen, and about one-quarter is helium, with no more than about 2% consisting of elements heavier than helium. During most of any s ...
... stars form in great clouds of gas and dust. Each star begins its life with roughly the same chemical composition: About three-quarters of the star’s mass at birth is hydrogen, and about one-quarter is helium, with no more than about 2% consisting of elements heavier than helium. During most of any s ...
HR DIAGRAMS OF STAR CLUSTERS
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
... your cluster HR diagram. Once you have matched the zero-age main-sequence, you can then call up the isochrone-fitting tool. On the menu bar of the ColorMagnitude diagram window, call up Tools > Isochrones, and you will see an isochrone plotted on your HR diagram near the plot of your cluster stars. ...
white dwarfs and the age of the universe
... During the crystallization process, the equilibrium chemical compositions of the solid and liquid plasmas are not equal. Therefore, if the resulting solid is denser than the liquid mixture, it sink towards the central region. If they are lighter, they rise upwards and melt when the solidification te ...
... During the crystallization process, the equilibrium chemical compositions of the solid and liquid plasmas are not equal. Therefore, if the resulting solid is denser than the liquid mixture, it sink towards the central region. If they are lighter, they rise upwards and melt when the solidification te ...
A Spectroscopic Survey of a Sample of Active M Dwarfs.
... all program and standard stars. Three well-observed M dwarfs were chosen as templates: HD36395 (Gliese 205), HD119850 (Gliese 526) and HD95735 (Gliese 411). Spectra of each of these stars taken 2001 Jan 3 were chosen because that night was exceptionally dry and cold (-16 C at the telescope secondary ...
... all program and standard stars. Three well-observed M dwarfs were chosen as templates: HD36395 (Gliese 205), HD119850 (Gliese 526) and HD95735 (Gliese 411). Spectra of each of these stars taken 2001 Jan 3 were chosen because that night was exceptionally dry and cold (-16 C at the telescope secondary ...
Superbubble Activity in Star-Forming Galaxies M. S. Oey
... emission have been identified: objects with X-ray luminosity Lx in excess of the model’s prediction (Chu & Mac Low 1990; Wang & Helfand 1991), and objects that remain undetected in X-rays (Chu et al. 1995). The X-ray–bright objects are thought to be overluminous because of SNR impacts on the shell w ...
... emission have been identified: objects with X-ray luminosity Lx in excess of the model’s prediction (Chu & Mac Low 1990; Wang & Helfand 1991), and objects that remain undetected in X-rays (Chu et al. 1995). The X-ray–bright objects are thought to be overluminous because of SNR impacts on the shell w ...
What CAN You See With a Telescope?
... Early astronomers had used their telescopes to measure the rotation rate of the Sun and some of the planets. Since the asteroids were thought to be “minor planets,” it was assumed that they also rotated on their own axes. In 1810, Schröeter 6 thought Juno had a 27hour rotation rate. This is abou ...
... Early astronomers had used their telescopes to measure the rotation rate of the Sun and some of the planets. Since the asteroids were thought to be “minor planets,” it was assumed that they also rotated on their own axes. In 1810, Schröeter 6 thought Juno had a 27hour rotation rate. This is abou ...
Document
... break technique in combination with the new generation of 8- to 10-m telescopes made it possible to identify significant samples of high-redshift objects. Lyman Break Galaxies (LBGs) are color-selected, luminous, star forming galaxies that emitted their light more than 10 billion years ago, e.g., at ...
... break technique in combination with the new generation of 8- to 10-m telescopes made it possible to identify significant samples of high-redshift objects. Lyman Break Galaxies (LBGs) are color-selected, luminous, star forming galaxies that emitted their light more than 10 billion years ago, e.g., at ...
Chromospherically young, kinematically old stars
... The chromospheric activity of a late-type star is frequently interpreted as a sign of its youth. Young dwarfs show high rotation rates, and the interaction between rotation and outer envelope convection is expected to drive the chromospheric activity. Nevertheless, not only young single stars presen ...
... The chromospheric activity of a late-type star is frequently interpreted as a sign of its youth. Young dwarfs show high rotation rates, and the interaction between rotation and outer envelope convection is expected to drive the chromospheric activity. Nevertheless, not only young single stars presen ...
Chapter 1: Introduction to Galaxies File - QMplus
... very little gas (and therefore very little dust), so almost all of the visible component is in the form of stars. With so little gas, there is no appreciable star formation, with the result that elliptical galaxies contain almost only old stars. Their colours are therefore red. K-type giant stars do ...
... very little gas (and therefore very little dust), so almost all of the visible component is in the form of stars. With so little gas, there is no appreciable star formation, with the result that elliptical galaxies contain almost only old stars. Their colours are therefore red. K-type giant stars do ...
Monday, Sept. 8 - University of Manitoba Physics Department
... The fraction of the outer circle covered by the diameter of the object is equal to the fraction of the inner circle covered by the angular ...
... The fraction of the outer circle covered by the diameter of the object is equal to the fraction of the inner circle covered by the angular ...
BSA Astronomy Merit Badge
... person, making skin-to-skin contact. Then cover both of your bodies with blankets. Provide warm beverages. If the affected person is alert and able to swallow, provide a warm, nonalcoholic, non-caffeinated beverage to help warm the body. Use warm, dry compresses. Use a first-aid warm compress (a pla ...
... person, making skin-to-skin contact. Then cover both of your bodies with blankets. Provide warm beverages. If the affected person is alert and able to swallow, provide a warm, nonalcoholic, non-caffeinated beverage to help warm the body. Use warm, dry compresses. Use a first-aid warm compress (a pla ...
a changing cosmos - Whittier Union High School District
... Walter Alvarez from the University of California at Berkeley. He was studying a thin layer of clay between rock layers of the Cretaceous Period (Age of Reptiles) and the Tertiary Period (containing no dinosaurs fossils). The clay layer contained very large amounts of the rare element iridium, which ...
... Walter Alvarez from the University of California at Berkeley. He was studying a thin layer of clay between rock layers of the Cretaceous Period (Age of Reptiles) and the Tertiary Period (containing no dinosaurs fossils). The clay layer contained very large amounts of the rare element iridium, which ...
ACTIVE GALAXIES
... • Two oppositely directed JETS emerge from the galactic nucleus • They often feed HOT-SPOTS and and LOBES on either side of the galaxy • Radio source sizes often 300 kpc or more --- much bigger than their host galaxies. • Head-tail radio galaxies arise when jets are bent by the ram-pressure of gas a ...
... • Two oppositely directed JETS emerge from the galactic nucleus • They often feed HOT-SPOTS and and LOBES on either side of the galaxy • Radio source sizes often 300 kpc or more --- much bigger than their host galaxies. • Head-tail radio galaxies arise when jets are bent by the ram-pressure of gas a ...
Brightness and Flux Density
... Astronomers learn about an astronomical source by measuring the strength of its radiation as a function of direction on the sky (by mapping or imaging) and frequency (spectroscopy), plus other quantities (time, polarization) that we ignore for now. We need precise and quantitative definitions to des ...
... Astronomers learn about an astronomical source by measuring the strength of its radiation as a function of direction on the sky (by mapping or imaging) and frequency (spectroscopy), plus other quantities (time, polarization) that we ignore for now. We need precise and quantitative definitions to des ...
Malmquist bias
The Malmquist bias is an effect in observational astronomy which leads to the preferential detection of intrinsically bright objects. It was first described in 1922 by Swedish astronomer Gunnar Malmquist (1893–1982), who then greatly elaborated upon this work in 1925. In statistics, this bias is referred to as a selection bias and affects the survey results in a brightness limited survey, where stars below a certain apparent brightness are not included. Since observed stars and galaxies appear dimmer when farther away, the brightness that is measured will fall off with distance until their brightness falls below the observational threshold. Objects which are more luminous, or intrinsically brighter, can be observed at a greater distance, creating a false trend of increasing intrinsic brightness, and other related quantities, with distance. This effect has led to many spurious claims in the field of astronomy. Properly correcting for these effects has become an area of great focus.