1 Pau Amaro Seoane - modest 15-s
... We present an expression of the external gravitational field of a general ring-like object with the axial and plane symmetries such as annular disks or oval toroids with an arbitrary density distribution. The main term is that of an infinitely thin ring (Fukushima, 2010, Celest. Mech. Dyn. Astron., ...
... We present an expression of the external gravitational field of a general ring-like object with the axial and plane symmetries such as annular disks or oval toroids with an arbitrary density distribution. The main term is that of an infinitely thin ring (Fukushima, 2010, Celest. Mech. Dyn. Astron., ...
Hands-On Radio Astronomy Mapping the Milky Way
... like to be able to embark on a spaceship and see the Galaxy from outside. Unfortunately, traveling in and around the Galaxy is (and will always be) out of the question because of the huge distances. We are condemned to observe the Galaxy from the vicinity of the Sun. In addition, some areas of the M ...
... like to be able to embark on a spaceship and see the Galaxy from outside. Unfortunately, traveling in and around the Galaxy is (and will always be) out of the question because of the huge distances. We are condemned to observe the Galaxy from the vicinity of the Sun. In addition, some areas of the M ...
Intro to the Night Sky - AST 114, Astronomy Lab II for Spring 2017!
... When one looks at the sky, or at the photos in the Audubon Guide, one quickly notices that all stars do not appear the same. There is a very wide range in brightness. Stars also appear in different colors. Astronomers occasionally use an archaic method of specifying the brightness of an object. This ...
... When one looks at the sky, or at the photos in the Audubon Guide, one quickly notices that all stars do not appear the same. There is a very wide range in brightness. Stars also appear in different colors. Astronomers occasionally use an archaic method of specifying the brightness of an object. This ...
55 Ignacio Negueruela and Amparo Marco
... stars (≈20), we determined an initial PSF by fitting the best function between the five options offered by the PSF routine inside DAOPHOT. We allowed the PSF to be variable (in order two) across the frame to take into account the systematic pattern of PSF variability with position on the chip. We ne ...
... stars (≈20), we determined an initial PSF by fitting the best function between the five options offered by the PSF routine inside DAOPHOT. We allowed the PSF to be variable (in order two) across the frame to take into account the systematic pattern of PSF variability with position on the chip. We ne ...
the inclination of the dwarf irregular galaxy
... In fact, for a sample of spiral galaxies and dwarf galaxies, Leroy et al. (2008) found that Qg has a so large scatter from galaxy to galaxy, that there is no a clear evidence of a universal Qg threshold marking the transition from high star formation efficiency to low star formation efficiency (see ...
... In fact, for a sample of spiral galaxies and dwarf galaxies, Leroy et al. (2008) found that Qg has a so large scatter from galaxy to galaxy, that there is no a clear evidence of a universal Qg threshold marking the transition from high star formation efficiency to low star formation efficiency (see ...
Chapter 25.2 - Planet Earth
... etermining how stars are born, age, and then die was difficult because the life of a star can span billions of years. However, by studying stars of different ages, astronomers have been able to piece together the evolution of a star. Imagine that an alien from outer space lands on Earth. This alien w ...
... etermining how stars are born, age, and then die was difficult because the life of a star can span billions of years. However, by studying stars of different ages, astronomers have been able to piece together the evolution of a star. Imagine that an alien from outer space lands on Earth. This alien w ...
Modelling the Ultra-Faint Dwarf Galaxies and Tidal
... • Progenitors with more than 105 Msun must be almost destroyed to account for the patchy structure, the low mass of the remnant and the high velocity dispersion of UMa II • Progenitors with more than 106 Msun do ...
... • Progenitors with more than 105 Msun must be almost destroyed to account for the patchy structure, the low mass of the remnant and the high velocity dispersion of UMa II • Progenitors with more than 106 Msun do ...
Scale the Universe - Crystal Ball Science
... • Since infrared energy waves are longer, they are easily absorbed into molecules, heating them up, like our french fries at MacDonald's • The dust between the stars also gives off infrared energy Winter 2008 ...
... • Since infrared energy waves are longer, they are easily absorbed into molecules, heating them up, like our french fries at MacDonald's • The dust between the stars also gives off infrared energy Winter 2008 ...
File
... Star System – consists of a star (sometimes more than one star) and all the objects that orbit it. ...
... Star System – consists of a star (sometimes more than one star) and all the objects that orbit it. ...
Using a Sextant Altitude The Concept Celestial Navigation Position
... minutes and seconds of the sight. For a Sun sight taken at exactly 30 minutes past the hour, the increment value would be 7° 30’.0, On the left hand side of the Increments page for the appropriate minutes, there is the correction to apply based on the tabulated “v” value for the body. The “v” correc ...
... minutes and seconds of the sight. For a Sun sight taken at exactly 30 minutes past the hour, the increment value would be 7° 30’.0, On the left hand side of the Increments page for the appropriate minutes, there is the correction to apply based on the tabulated “v” value for the body. The “v” correc ...
Galaxy Sorting
... galaxies contain mostly old stars, with very little gas and dust found between stars. Since new stars form from clouds of interstellar gas and dust, elliptical galaxies lack the raw ingredients to make new stars. Spiral galaxies, on the other hand, have a mix of young and old stars. Interstellar ...
... galaxies contain mostly old stars, with very little gas and dust found between stars. Since new stars form from clouds of interstellar gas and dust, elliptical galaxies lack the raw ingredients to make new stars. Spiral galaxies, on the other hand, have a mix of young and old stars. Interstellar ...
Spiral Galaxies: Density Waves
... bright blue OB stars. These stars will continue to drift through the region. • The OB stars don’t go far before they explode. The brightest (and bluest) of a galaxy’s stars will never be far from the spiral arm where they were born. ...
... bright blue OB stars. These stars will continue to drift through the region. • The OB stars don’t go far before they explode. The brightest (and bluest) of a galaxy’s stars will never be far from the spiral arm where they were born. ...
van der Wel et al., 2004, ApJ, 602, L5 - ST-ECF
... 2003), and this is most likely due to (still unexplained) sample selection effects. The last authors found that galaxies with residuals from the r 1/4 profile had young ages. However, we find no such relation in our sample. Stellar population models indicate that the low M/L of the blue z ≈ 1 galaxi ...
... 2003), and this is most likely due to (still unexplained) sample selection effects. The last authors found that galaxies with residuals from the r 1/4 profile had young ages. However, we find no such relation in our sample. Stellar population models indicate that the low M/L of the blue z ≈ 1 galaxi ...
Models for the Magnitude-Distribution of Brightest Cluster Galaxies
... The brightest, or first-ranked, galaxies (BCGs) in rich clusters show a very small dispersion in luminosity, making them excellent standard candles. This small dispersion raises questions about the nature of BCGs. Are they simply the extremes of normal galaxies formed via a stochastic process, or do ...
... The brightest, or first-ranked, galaxies (BCGs) in rich clusters show a very small dispersion in luminosity, making them excellent standard candles. This small dispersion raises questions about the nature of BCGs. Are they simply the extremes of normal galaxies formed via a stochastic process, or do ...
Galaxies and their properties
... Disk galaxies are highly flattened systems supported by rotation. Thus, they are formed through the dissipational collapse of a gas cloud with some initial angular momentum. This occurs for hot clouds, T > 104 K, as they efficiently radiate their binding energy and contract, until its energy reaches ...
... Disk galaxies are highly flattened systems supported by rotation. Thus, they are formed through the dissipational collapse of a gas cloud with some initial angular momentum. This occurs for hot clouds, T > 104 K, as they efficiently radiate their binding energy and contract, until its energy reaches ...
Chapter 30: Stars
... Solar flares are violent eruptions of particles and radiation from the surface of the Sun, as shown in Figure 30-6A. Often, the released particles escape the surface of the Sun in the solar wind and Earth gets bombarded with the particles a few days later. The largest solar flare on record, which oc ...
... Solar flares are violent eruptions of particles and radiation from the surface of the Sun, as shown in Figure 30-6A. Often, the released particles escape the surface of the Sun in the solar wind and Earth gets bombarded with the particles a few days later. The largest solar flare on record, which oc ...
Stellar populations in the intergalactic space (invited talk)
... ICPNe in the Vigo cluster: projected phase-space distribution • PNe trace light because the luminosity-specific stellar death rate should be independent of the precise state of the underlying stellar population (Renzini & Buzzoni 1986). • The [OIII] line emission at 5007Å is the strongest emission ...
... ICPNe in the Vigo cluster: projected phase-space distribution • PNe trace light because the luminosity-specific stellar death rate should be independent of the precise state of the underlying stellar population (Renzini & Buzzoni 1986). • The [OIII] line emission at 5007Å is the strongest emission ...
Supernovae and compact objects
... I noticed that a new and unusual star, surpassing the other stars in brilliancy, was shining almost directly above my head; and since I had, from boyhood, known all the stars of the heavens perfectly, it was quite evident to me that there had never been any star in that place of the sky, even the sm ...
... I noticed that a new and unusual star, surpassing the other stars in brilliancy, was shining almost directly above my head; and since I had, from boyhood, known all the stars of the heavens perfectly, it was quite evident to me that there had never been any star in that place of the sky, even the sm ...
Genesis of the Heaviest Elements in the Milky Way Galaxy
... capture elements are below the solar levels, the -capture element abundances in this star are the same as the solar system elemental -process-only abundances. This similarity in abundance levels has now been observed in several other halo stars (17). There is an additional, apparently rare, anom ...
... capture elements are below the solar levels, the -capture element abundances in this star are the same as the solar system elemental -process-only abundances. This similarity in abundance levels has now been observed in several other halo stars (17). There is an additional, apparently rare, anom ...
" Galaxy," Defined
... A growing number of low luminosity and low surface brightness astronomical objects challenge traditional notions of both galaxies and star clusters. To address this challenge, we propose a definition of galaxy that does not depend on a cold dark matter model of the universe: A galaxy is a gravitatio ...
... A growing number of low luminosity and low surface brightness astronomical objects challenge traditional notions of both galaxies and star clusters. To address this challenge, we propose a definition of galaxy that does not depend on a cold dark matter model of the universe: A galaxy is a gravitatio ...
Lecture17
... of mass are changed to energy in nuclear reactions • Often one hears that E=mc2 applies only to nuclear reactions and nuclear explosions ...
... of mass are changed to energy in nuclear reactions • Often one hears that E=mc2 applies only to nuclear reactions and nuclear explosions ...
Mapping the Universe - Tufts Institute of Cosmology
... tens of yards. In randomly picking out deer in the forest, you would notice that you are much more likely to find another deer a few yards away than a few hundred yards away. The correlation function would show a strong positive signal on the scale of a few tens of yards and a weak or negative signa ...
... tens of yards. In randomly picking out deer in the forest, you would notice that you are much more likely to find another deer a few yards away than a few hundred yards away. The correlation function would show a strong positive signal on the scale of a few tens of yards and a weak or negative signa ...
Basic principles of celestial navigation
... Imagine that a terrestrial observer is located at a fixed point P of unknown latitude % and longitude &. The celestial sphere rotates westward from the observer’s point of view at an angular rate such that the vernal equinox transits !passes through" the observer’s meridian from east to west at inte ...
... Imagine that a terrestrial observer is located at a fixed point P of unknown latitude % and longitude &. The celestial sphere rotates westward from the observer’s point of view at an angular rate such that the vernal equinox transits !passes through" the observer’s meridian from east to west at inte ...
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an astronomical object is possible only for those objects that are ""close enough"" (within about a thousand parsecs) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a standard candle, which is an astronomical object that has a known luminosity.The ladder analogy arises because no one technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung.