Chapter 19 Star Formation
... Individual cloud fragments begin to collapse. Once the density is high enough, there is no further fragmentation. Reason: the star has become opaque to its own radiation: It has a photosphere! After this, the ‘trapped radiation heats the interior of the object as it contracts. Stage 3: Object become ...
... Individual cloud fragments begin to collapse. Once the density is high enough, there is no further fragmentation. Reason: the star has become opaque to its own radiation: It has a photosphere! After this, the ‘trapped radiation heats the interior of the object as it contracts. Stage 3: Object become ...
Astronomy Mastery Objectives Semester Exam Review Kepler Telescope
... As the Earth rotates counter- clockwise, the side facing the Moon will experience a rise of tidal waters until it reaches High Tide, or when the Moon’s gravitational pull on the tidal water is greatest. A High tide will simultaneously occur on the opposite side of the Earth because the Moon is actua ...
... As the Earth rotates counter- clockwise, the side facing the Moon will experience a rise of tidal waters until it reaches High Tide, or when the Moon’s gravitational pull on the tidal water is greatest. A High tide will simultaneously occur on the opposite side of the Earth because the Moon is actua ...
Joining the Party - Lincoln-Sudbury Regional High School
... You start off with a large cool cloud (which we’ll call a protostellar cloud), and gravity collapses it into a smaller, hotter cloud. In a larger, cooler cloud, the protons are moving more slowly and tend to be further apart. That is, the gas is at a low temperature and a low pressure. The protons h ...
... You start off with a large cool cloud (which we’ll call a protostellar cloud), and gravity collapses it into a smaller, hotter cloud. In a larger, cooler cloud, the protons are moving more slowly and tend to be further apart. That is, the gas is at a low temperature and a low pressure. The protons h ...
1 Ay 124 Winter 2014 – HOMEWORK #3
... Problem 1 The nearest spiral galaxy to the Milky Way, M31, has a very concentrated nucleus. At a projected radius of 1 arcsec, stars in the nucleus have a line of sight velocity dispersion of 150 km s−1 , and are also rotating about the nucleus at 150 km s−1 . The total luminosity from within 1 arc ...
... Problem 1 The nearest spiral galaxy to the Milky Way, M31, has a very concentrated nucleus. At a projected radius of 1 arcsec, stars in the nucleus have a line of sight velocity dispersion of 150 km s−1 , and are also rotating about the nucleus at 150 km s−1 . The total luminosity from within 1 arc ...
doc - University of Texas Astronomy
... fall right onto the star, but must for a rotating disk, whose gas gradually loses angular momentum by not-veryunderstood processes: an “accretion disk.” These occur on every scale in the universe, around many objects (protostellar disks were one variety). Here is a picture of an accretion disk formi ...
... fall right onto the star, but must for a rotating disk, whose gas gradually loses angular momentum by not-veryunderstood processes: an “accretion disk.” These occur on every scale in the universe, around many objects (protostellar disks were one variety). Here is a picture of an accretion disk formi ...
The Death of Massive Stars
... • This heats the atmosphere which then expands to a point that the star’s trapped radiation can escape. • This causes the atmosphere to cool, shrink to its original size, and start the process all over again. • The regular pulsation process of variable stars has led to the period-luminosity relation ...
... • This heats the atmosphere which then expands to a point that the star’s trapped radiation can escape. • This causes the atmosphere to cool, shrink to its original size, and start the process all over again. • The regular pulsation process of variable stars has led to the period-luminosity relation ...
Document
... _____ 5. A scientist can identify a star’s composition by looking at a. the star’s prism. b. the star’s continuous spectrum. c. the star’s absorption spectrum. d. the star’s color. _____ 6. If the universe expands forever, a. the universe will collapse. b. the universe will repeat itself. c. the uni ...
... _____ 5. A scientist can identify a star’s composition by looking at a. the star’s prism. b. the star’s continuous spectrum. c. the star’s absorption spectrum. d. the star’s color. _____ 6. If the universe expands forever, a. the universe will collapse. b. the universe will repeat itself. c. the uni ...
Notes_ stars and sun
... • Astronomers studying the sky sometimes see these clouds and mistake them for galaxies. • Nebulae come in a variety of shapes and sizes. Some are named because of the shape that they form. • These clouds gradually shrink as gravity pulls the dust and gas together. • At the center, the gas gets ...
... • Astronomers studying the sky sometimes see these clouds and mistake them for galaxies. • Nebulae come in a variety of shapes and sizes. Some are named because of the shape that they form. • These clouds gradually shrink as gravity pulls the dust and gas together. • At the center, the gas gets ...
Introduction
... Similarly, can you estimate the lifetime of the Sun if it were powered by the gravitational energy alone? Now what is the lifetime of the Sun with the nuclear power? What is the dynamic scale of the Sun? What is the virial theorem? Can you derive an expression of the gravitational potential for a st ...
... Similarly, can you estimate the lifetime of the Sun if it were powered by the gravitational energy alone? Now what is the lifetime of the Sun with the nuclear power? What is the dynamic scale of the Sun? What is the virial theorem? Can you derive an expression of the gravitational potential for a st ...
New light on our Sun`s fate - Space Telescope Science Institute
... began to wonder how stars evolve and thought that perhaps they “move” across the H-R diagram. Over decades, we’ve learned that a star’s mass controls its life; along the way, that property also determines its brightness and temperature. We now summarize all stages of stellar evolution on this import ...
... began to wonder how stars evolve and thought that perhaps they “move” across the H-R diagram. Over decades, we’ve learned that a star’s mass controls its life; along the way, that property also determines its brightness and temperature. We now summarize all stages of stellar evolution on this import ...
30-3
... In the space provided, write the letter of the definition that best matches the type of galaxy. ...
... In the space provided, write the letter of the definition that best matches the type of galaxy. ...
Finding Black Holes
... How Do We Study Millions of Stars at Once? 1. Find a collection of many stars at some moderately large distance – like a nearby galaxy – so they can all be captured in a single big image. 2. Then take picture after picture, day after day, week after week, year after year, and look for short-lived ...
... How Do We Study Millions of Stars at Once? 1. Find a collection of many stars at some moderately large distance – like a nearby galaxy – so they can all be captured in a single big image. 2. Then take picture after picture, day after day, week after week, year after year, and look for short-lived ...
Chapter 10 Measuring the Stars: Giants, Dwarfs, and the Main
... • 1st order stars are 2.512 times brighter than 2nd order stars • 1st order stars are 100 times brighter than 6th order stars ...
... • 1st order stars are 2.512 times brighter than 2nd order stars • 1st order stars are 100 times brighter than 6th order stars ...
Finding Black Holes Left Behind by Single Stars
... How Do We Study Millions of Stars at Once? 1. Find a collection of many stars at some moderately large distance – like a nearby galaxy – so they can all be captured in a single big image. 2. Then take picture after picture, day after day, week after week, year after year, and look for short-lived ch ...
... How Do We Study Millions of Stars at Once? 1. Find a collection of many stars at some moderately large distance – like a nearby galaxy – so they can all be captured in a single big image. 2. Then take picture after picture, day after day, week after week, year after year, and look for short-lived ch ...
STARS Chapter 8 Section 1
... What are stars made of? • Stars are made of gas. Hydrogen(H) and helium(He) are the two main elements that make up a star. • What is an element? • Stars also contain small amounts of other elements, such as carbon, nitrogen, and oxygen. Each star is made up of a different mix. • To find out what a ...
... What are stars made of? • Stars are made of gas. Hydrogen(H) and helium(He) are the two main elements that make up a star. • What is an element? • Stars also contain small amounts of other elements, such as carbon, nitrogen, and oxygen. Each star is made up of a different mix. • To find out what a ...
TMSP Stellar Evolution & Life
... Simplified illustration of the evolution of a star with the mass of the Sun •The star forms from a collapsing nebula, or cloud of gas (1) •then undergoes a contraction period as a protostar (2) •before joining the main sequence (3). •Once the Hydrogen at the core is consumed it expands into a red g ...
... Simplified illustration of the evolution of a star with the mass of the Sun •The star forms from a collapsing nebula, or cloud of gas (1) •then undergoes a contraction period as a protostar (2) •before joining the main sequence (3). •Once the Hydrogen at the core is consumed it expands into a red g ...
Mapping the Stars
... What happens as the sphere becomes denser? It gets hotter and the hydrogen changes to helium. What is that process called? Nuclear fusion. What happens when a star dies? Some of the material returns to space and combines with more gas and dust to form new stars. ...
... What happens as the sphere becomes denser? It gets hotter and the hydrogen changes to helium. What is that process called? Nuclear fusion. What happens when a star dies? Some of the material returns to space and combines with more gas and dust to form new stars. ...
dtu7ech11 - Fort Thomas Independent Schools
... Not necessarily. Many brighter stars, such as red giants, are cooler but larger than hotter, dimmer stars, such as white dwarfs. What sizes are stars? Stars range from more than 1000 times the Sun’s diameter to less than 1/100 the Sun’s diameter. Are most stars isolated from other stars, as the Sun ...
... Not necessarily. Many brighter stars, such as red giants, are cooler but larger than hotter, dimmer stars, such as white dwarfs. What sizes are stars? Stars range from more than 1000 times the Sun’s diameter to less than 1/100 the Sun’s diameter. Are most stars isolated from other stars, as the Sun ...
HEIC0410: FOR RELEASE 15:00 (CEST)/9:00 AM EDT 15 June
... Both components of the binary system belong to the L spectral class that includes the lowest mass stars and the highest mass brown dwarfs in our solar neighbourhood. This spectral class was discovered in 1997 and was added to the spectral classification that had remained unchanged for half a century ...
... Both components of the binary system belong to the L spectral class that includes the lowest mass stars and the highest mass brown dwarfs in our solar neighbourhood. This spectral class was discovered in 1997 and was added to the spectral classification that had remained unchanged for half a century ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.