April News Letter - Boise Astronomical Society
... of hydrogen at a faster rate than the sun. As a result, Regulus shines 240 times brighter than our sun. If viewed from Regulus, our sun would be so dim that we could not see it without the aid of a telescope. However, Regulus is easily seen in town. Regulus has a faint companion star that orbits it ...
... of hydrogen at a faster rate than the sun. As a result, Regulus shines 240 times brighter than our sun. If viewed from Regulus, our sun would be so dim that we could not see it without the aid of a telescope. However, Regulus is easily seen in town. Regulus has a faint companion star that orbits it ...
Stars PowerPoint
... • Parallax is the apparent shift in position of an object caused by the motion of the observer. ...
... • Parallax is the apparent shift in position of an object caused by the motion of the observer. ...
Chapter 20
... when there is no more hydrogen fuel in their cores. The first few events are similar to those in lower-mass stars—first a hydrogen shell, then a core burning helium to ...
... when there is no more hydrogen fuel in their cores. The first few events are similar to those in lower-mass stars—first a hydrogen shell, then a core burning helium to ...
Today`s Powerpoint
... Not enough radiating matter at large R to explain rotation curve => "dark" matter! Dark matter must be about 90% of the mass! Composition unknown. Probably mostly exotic particles that don't interact with ordinary matter at all (except gravity). Some may be brown dwarfs, dead white dwarfs … Most li ...
... Not enough radiating matter at large R to explain rotation curve => "dark" matter! Dark matter must be about 90% of the mass! Composition unknown. Probably mostly exotic particles that don't interact with ordinary matter at all (except gravity). Some may be brown dwarfs, dead white dwarfs … Most li ...
the rest of the univ..
... extremely faint Kuiper Belt objects (left). The objects are very small and faint perhaps only 20 km or so across. There may be as many as 100 million such comets in low-inclination orbits and shining brighter than the HST's magnitude-28 limit. (A follow-up HST observation failed to confirm this obse ...
... extremely faint Kuiper Belt objects (left). The objects are very small and faint perhaps only 20 km or so across. There may be as many as 100 million such comets in low-inclination orbits and shining brighter than the HST's magnitude-28 limit. (A follow-up HST observation failed to confirm this obse ...
Summary: Modes of Star Formation
... has been suggested that all of these events might have been caused by a close encounter among the three galaxies a few Gyr ago. Some anomalies in the spatial distribution of gas and young stars in our Galaxy, such as the Gould Belt and other corrugations or warps, might also have been caused by rece ...
... has been suggested that all of these events might have been caused by a close encounter among the three galaxies a few Gyr ago. Some anomalies in the spatial distribution of gas and young stars in our Galaxy, such as the Gould Belt and other corrugations or warps, might also have been caused by rece ...
Nova
... space by the nova. Another Hubble picture taken 467 days after the explosion [left] provided the first glimpse of the ring and a mysterious bar-like structure. But the image interpretation was severely hampered by the telescope's blurred vision ...
... space by the nova. Another Hubble picture taken 467 days after the explosion [left] provided the first glimpse of the ring and a mysterious bar-like structure. But the image interpretation was severely hampered by the telescope's blurred vision ...
Chapter 1
... Sun- 8 minutes ago Saturn- 80 minutes ago Sirius (the brightest star)- 8.5 years ago Andromeda galaxy- 2.2 million years ago ...
... Sun- 8 minutes ago Saturn- 80 minutes ago Sirius (the brightest star)- 8.5 years ago Andromeda galaxy- 2.2 million years ago ...
Universe 8e Lecture Chapter 24 Galaxies
... The Hubble Law: There is a simple linear relationship between the distance from the Earth to a remote galaxy and the redshift of that galaxy (which is a measure of the speed with which it is receding from us). This relationship is the Hubble law, v = H0d. The value of the Hubble constant, H0, is not ...
... The Hubble Law: There is a simple linear relationship between the distance from the Earth to a remote galaxy and the redshift of that galaxy (which is a measure of the speed with which it is receding from us). This relationship is the Hubble law, v = H0d. The value of the Hubble constant, H0, is not ...
Sakurai`s Object - Department of Physics, HKU
... others pointed out that the slow brightness evolution and the C-rich and H-poor spectrum suggest that this object may be undergoing its final helium flash stage. ...
... others pointed out that the slow brightness evolution and the C-rich and H-poor spectrum suggest that this object may be undergoing its final helium flash stage. ...
Progenitor and environment of the peculiar red nova V838 Mon
... We observed how emission spectrum of ionized gas increased its intensity. In 2009, neither the hot companion nor the emission spectrum are seen. The residual intensity at minimum of the TiO bands is zero. Thus, the hot companion plunged into the expanding ...
... We observed how emission spectrum of ionized gas increased its intensity. In 2009, neither the hot companion nor the emission spectrum are seen. The residual intensity at minimum of the TiO bands is zero. Thus, the hot companion plunged into the expanding ...
UNIVERSITY OF BRISTOL
... optical depth . If is the emissivity per unit volume of the stars, write down the observed intensity (outside the slab) from a volume element of thickness dx a distance x into the cloud. Hence, by integration, show that the total absorption, as seen by an external observer is ...
... optical depth . If is the emissivity per unit volume of the stars, write down the observed intensity (outside the slab) from a volume element of thickness dx a distance x into the cloud. Hence, by integration, show that the total absorption, as seen by an external observer is ...
Star formation PowerPoint
... 19.3 Stars of Other Masses The main sequence is a band, rather than a line, because stars of the same mass can have different compositions. Most important: Stars do not move along the main sequence! Once they reach it, they are in equilibrium and do not move until their fuel begins to run out. ...
... 19.3 Stars of Other Masses The main sequence is a band, rather than a line, because stars of the same mass can have different compositions. Most important: Stars do not move along the main sequence! Once they reach it, they are in equilibrium and do not move until their fuel begins to run out. ...
Plotting Variable Stars on the H
... Miras and Cepheids are especially elongated because of these expansions and contractions. Some pulsating variable stars change in temperature by two spectral classes during one cycle of change from maximum to minimum. To better understand the degree of variation for individual variable stars, it is ...
... Miras and Cepheids are especially elongated because of these expansions and contractions. Some pulsating variable stars change in temperature by two spectral classes during one cycle of change from maximum to minimum. To better understand the degree of variation for individual variable stars, it is ...
Project 3. Colour in Astronomy
... U=B=V=R=I=0 This does not mean that Vega show the same brightness through all filters. It is an arbitrary decision taken by the astronomers who have agreed on taking Vega as the zero point for the magnitude scale. Exercise 2: Spica and Antares are two well-known stars with colour indices (B-V)=0.13 ...
... U=B=V=R=I=0 This does not mean that Vega show the same brightness through all filters. It is an arbitrary decision taken by the astronomers who have agreed on taking Vega as the zero point for the magnitude scale. Exercise 2: Spica and Antares are two well-known stars with colour indices (B-V)=0.13 ...
Physics- HSC- Module 9.7 Astrophysics
... stars in a globular cluster 2. (Act 13) analyse information from a H-R diagram and use available evidence to determine the characteristics of a star and its evolutionary ...
... stars in a globular cluster 2. (Act 13) analyse information from a H-R diagram and use available evidence to determine the characteristics of a star and its evolutionary ...
Unit 1
... 10. If the universe were contracting instead of expanding, how would we know (what would the observations be)? 11. The Andromeda galaxy and the Milky Way are rushing toward each other at a velocity of 130 km/s (or, 300,000 mph!). We will collide in about 60 billion years. Andromeda is about one and ...
... 10. If the universe were contracting instead of expanding, how would we know (what would the observations be)? 11. The Andromeda galaxy and the Milky Way are rushing toward each other at a velocity of 130 km/s (or, 300,000 mph!). We will collide in about 60 billion years. Andromeda is about one and ...
SkyWatcher - Boise Astronomical Society
... Mercury is present low in the morning sky for most of the month. It brightens from magnitude -0.2 to -1.2 while decreasing in apparent size from 5.6 to 4.9 arc seconds. Mercury is at aphelion on February 7th and is at greatest heliocentric latitude south on February 27th. Venus becomes an increasing ...
... Mercury is present low in the morning sky for most of the month. It brightens from magnitude -0.2 to -1.2 while decreasing in apparent size from 5.6 to 4.9 arc seconds. Mercury is at aphelion on February 7th and is at greatest heliocentric latitude south on February 27th. Venus becomes an increasing ...
Stellar Evolution: Evolution: Birth, Life, and Death of Stars
... (brightness) as a function of temperature (spectral class); the ordinate "absolute magnitude" is a logarithmic measure of power. Most of the stars lie on the “main sequence”: massive stars are hot and have high power (top left), while the small stars have lower masses, are cold and have low power ...
... (brightness) as a function of temperature (spectral class); the ordinate "absolute magnitude" is a logarithmic measure of power. Most of the stars lie on the “main sequence”: massive stars are hot and have high power (top left), while the small stars have lower masses, are cold and have low power ...
Binary Stars
... We detect the existence of a binary because a star ‘wobbles’ in position as it moves across the sky. Sirius is a good example: ...
... We detect the existence of a binary because a star ‘wobbles’ in position as it moves across the sky. Sirius is a good example: ...
Implications of the Search and Discovery
... • Perhaps life in “oceans” beneath cloudy atmosphere ...
... • Perhaps life in “oceans” beneath cloudy atmosphere ...
blackbody
... 2) In the Applet, the closest temperature to 3391 K you can input is about 3364 K. The peak of the curve does indeed occur at about 900 nm which is in the infrared part of the spectrum (meaning wavelengths longer than the red light). Note the color of the star has a dusky reddish/brown appearance. Y ...
... 2) In the Applet, the closest temperature to 3391 K you can input is about 3364 K. The peak of the curve does indeed occur at about 900 nm which is in the infrared part of the spectrum (meaning wavelengths longer than the red light). Note the color of the star has a dusky reddish/brown appearance. Y ...
Perseus (constellation)
Perseus, named after the Greek mythological hero Perseus, is a constellation in the northern sky. It was one of 48 listed by the 2nd-century astronomer Ptolemy and among the 88 modern constellations defined by the International Astronomical Union (IAU). It is located in the northern celestial hemisphere near several other constellations named after legends surrounding Perseus, including Andromeda to the west and Cassiopeia to the north. Perseus is also bordered by Aries and Taurus to the south, Auriga to the east, Camelopardalis to the north, and Triangulum to the west.The galactic plane of the Milky Way passes through Perseus but is mostly obscured by molecular clouds. The constellation's brightest star is the yellow-white supergiant Alpha Persei (also called Mirfak), which shines at magnitude 1.79. It and many of the surrounding stars are members of an open cluster known as the Alpha Persei Cluster. The best-known star, however, is Algol (Beta Persei), linked with ominous legends because of its variability, which is noticeable to the naked eye. Rather than being an intrinsically variable star, it is an eclipsing binary. Other notable star systems in Perseus include X Persei, a binary system containing a neutron star, and GK Persei, a nova that peaked at magnitude 0.2 in 1901. The Double Cluster, comprising two open clusters quite near each other in the sky, was known to the ancient Chinese. The constellation gives its name to the Perseus Cluster (Abell 426), a massive galaxy cluster located 250 million light-years from Earth. It hosts the radiant of the annual Perseids meteor shower—one of the most prominent meteor showers in the sky.