Review: How does a star`s mass determine its life story?
... One way to tell supernova types apart is with a light curve showing how luminosity changes with time. ...
... One way to tell supernova types apart is with a light curve showing how luminosity changes with time. ...
19Nov_2014
... electrons merge into neutrons, taking energy away from the core • The core collapses, and the layers above fall rapidly toward the center, where they collide with the core material and “bounce” • The “bounced material collides with the remaining infalling gas, raising temperatures high enough to set ...
... electrons merge into neutrons, taking energy away from the core • The core collapses, and the layers above fall rapidly toward the center, where they collide with the core material and “bounce” • The “bounced material collides with the remaining infalling gas, raising temperatures high enough to set ...
Lecture 24, PPT version
... • Pulsars (rapidly-rotating neutron stars left over after a high-mass star supernova) • Hypernova gives rise to a few-second burst of gamma rays and leaves behind a black hole (progenitor star would have had a main sequence mass > 40 Msun) • Introduction to the Milky Way • Face-on vs. edge-on perspe ...
... • Pulsars (rapidly-rotating neutron stars left over after a high-mass star supernova) • Hypernova gives rise to a few-second burst of gamma rays and leaves behind a black hole (progenitor star would have had a main sequence mass > 40 Msun) • Introduction to the Milky Way • Face-on vs. edge-on perspe ...
distance to the centre of the Milky Way.
... In ~1900, “Universe” = the distribution of stars within which we find ourselves (i.e. the Milky Way). It was believed to lie in a vast (perhaps infinite) void. ...
... In ~1900, “Universe” = the distribution of stars within which we find ourselves (i.e. the Milky Way). It was believed to lie in a vast (perhaps infinite) void. ...
ASTRONOMY 1102 1
... example of what the test will look like and a couple of examples of questions and problems. Review class notes: do not memorize rst, understand rst, and then commit to memory only a few basic de nitions and laws. Review homework. The basic properties of stars and the H{R diagram ARE NECESSARY BACK ...
... example of what the test will look like and a couple of examples of questions and problems. Review class notes: do not memorize rst, understand rst, and then commit to memory only a few basic de nitions and laws. Review homework. The basic properties of stars and the H{R diagram ARE NECESSARY BACK ...
Aug 2015 supplement - Hermanus Astronomy
... When the first galaxies started to form a few hundred million years after the Big Bang, the universe was full of a fog of hydrogen gas. But as more and more brilliant sources - both stars and quasars powered by huge black holes started to shine, they cleared away the mist and made the universe trans ...
... When the first galaxies started to form a few hundred million years after the Big Bang, the universe was full of a fog of hydrogen gas. But as more and more brilliant sources - both stars and quasars powered by huge black holes started to shine, they cleared away the mist and made the universe trans ...
EXERCISES: Set 2 of 4 Q1: The absolute magnitude of the Sun in
... (a) At what distances would: (i) a star like the Sun, (ii) a globular cluster, (iii) a galaxy like the Milky Way be as bright as the background sky? You can assume that in all three cases the distances involved are sufficiently large that the astronomical sources in question can be safely considered ...
... (a) At what distances would: (i) a star like the Sun, (ii) a globular cluster, (iii) a galaxy like the Milky Way be as bright as the background sky? You can assume that in all three cases the distances involved are sufficiently large that the astronomical sources in question can be safely considered ...
The Milky Way Galaxy
... • The Milky Way galaxy is home to 400 billion stars and our own Sun and Solar System. • It is a barred spiral galaxy. • Scientists think the centre of the galaxy contains a super massive black hole. • The Milky Way is full of dust, gas and stars. • The Milky Way, along with everything else, is ...
... • The Milky Way galaxy is home to 400 billion stars and our own Sun and Solar System. • It is a barred spiral galaxy. • Scientists think the centre of the galaxy contains a super massive black hole. • The Milky Way is full of dust, gas and stars. • The Milky Way, along with everything else, is ...
B. protostar - University of Maryland Astronomy
... 23. A gigantic outburst of energy and particles occurred on the Sun this morning. Mrs. Deming was excited and told her ASTR 101 class to look for A. a full moon tonight. B. an eclipse. C. a meteor shower if it is clear. D. an aurora if it is clear. E. dangerous cosmic rays. 24. Which of the followi ...
... 23. A gigantic outburst of energy and particles occurred on the Sun this morning. Mrs. Deming was excited and told her ASTR 101 class to look for A. a full moon tonight. B. an eclipse. C. a meteor shower if it is clear. D. an aurora if it is clear. E. dangerous cosmic rays. 24. Which of the followi ...
Galaxies
... far you look in the universe, you will find galaxies The challenge astronomers face is interpreting these two-dimensional pictures of a four-dimensional ...
... far you look in the universe, you will find galaxies The challenge astronomers face is interpreting these two-dimensional pictures of a four-dimensional ...
Star Jeopardy Review #2
... They do not evolve off until helium is built up. Most of stars life time is spent as a main sequence star. ...
... They do not evolve off until helium is built up. Most of stars life time is spent as a main sequence star. ...
White Dwarfs and Neutron Stars
... • Neutron stars can form powerful jets of matter and energy • Previously only thought possible with black holes • Binary system with neutron star gaining matter from white dwarf companion’s atmosphere in an accretion disk • Neutron star is tiny compared to white dwarf but is very dense and about 14 ...
... • Neutron stars can form powerful jets of matter and energy • Previously only thought possible with black holes • Binary system with neutron star gaining matter from white dwarf companion’s atmosphere in an accretion disk • Neutron star is tiny compared to white dwarf but is very dense and about 14 ...
Stars and Galaxies
... 5. White dwarf: outer layers escape into space, the star collapses into a dense hot, dim star smaller than Earth. Path of a star much larger than our sun ...
... 5. White dwarf: outer layers escape into space, the star collapses into a dense hot, dim star smaller than Earth. Path of a star much larger than our sun ...
Cosmology, galaxies, stars and the sun
... enough, nuclear fusion will begin. •Nuclear fusion converts hydrogen to helium in the core of a star. Once this begins, the star becomes more stable between the outward force of gravity and the inward force of gravity. ...
... enough, nuclear fusion will begin. •Nuclear fusion converts hydrogen to helium in the core of a star. Once this begins, the star becomes more stable between the outward force of gravity and the inward force of gravity. ...
Astronomy Notes: Deep Space
... Lightyear :out 10 trillion km, (or about 6 trillion miles ) Nearest star to our solar system: Proxima Centauri 4.2 ly (lightyear): (one parsec). Parallax measures the shift of a star compared to background stars. Electromagnetic Spectrum: energy given off in transverse waves. P. 14 ESRT 2. All EME t ...
... Lightyear :out 10 trillion km, (or about 6 trillion miles ) Nearest star to our solar system: Proxima Centauri 4.2 ly (lightyear): (one parsec). Parallax measures the shift of a star compared to background stars. Electromagnetic Spectrum: energy given off in transverse waves. P. 14 ESRT 2. All EME t ...
Galaxy Far Far Away ppt
... the galaxy. HALO: Area surrounding galaxy that contains some scattered globular clusters. DISK: Contains most of the stars in the galaxy. ...
... the galaxy. HALO: Area surrounding galaxy that contains some scattered globular clusters. DISK: Contains most of the stars in the galaxy. ...
Lec 25.2- STELLAR EVOLUTION SUMMARY
... be gravitationally bound. At this point, the cloud collapses under the influence of its own gravity. At first, it contracts rapidly because energy thereby released is easily radiated outward. Eventually, the cloud grows dense enough to become opaque to (block) its own radiation. This causes the clou ...
... be gravitationally bound. At this point, the cloud collapses under the influence of its own gravity. At first, it contracts rapidly because energy thereby released is easily radiated outward. Eventually, the cloud grows dense enough to become opaque to (block) its own radiation. This causes the clou ...
ISP 205 Review Questions, Week 13
... 2. A pulsating variable star has a period of 10 days. About how many times more luminous is it than the Sun? Refer to Fig. 15.12 in the textbook. It is about 3000 times more luminous than the Sun. Once you know the star’s luminosity L, you can calculate its distance r from the measured apparent bri ...
... 2. A pulsating variable star has a period of 10 days. About how many times more luminous is it than the Sun? Refer to Fig. 15.12 in the textbook. It is about 3000 times more luminous than the Sun. Once you know the star’s luminosity L, you can calculate its distance r from the measured apparent bri ...
THE MILKY WAY GALAXY
... disk, from our perspective more stars are visible looking through the disk then are seen looking away from the disk. The nature and size of the Galaxy, as well as our location within this stellar system were finally appreciated in the early 20th century when: The locations of the globular clusters ...
... disk, from our perspective more stars are visible looking through the disk then are seen looking away from the disk. The nature and size of the Galaxy, as well as our location within this stellar system were finally appreciated in the early 20th century when: The locations of the globular clusters ...
Our Universe
... •Our Sun has around 5 Billion years remaining. It is predicted to only exist for 10 Billion total years. ...
... •Our Sun has around 5 Billion years remaining. It is predicted to only exist for 10 Billion total years. ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.