NASA`s Chandra Sees Brightest Supernova Ever
... The mass-loss rate for the progenitor from x-ray data is about 5 × 10−4 M⊙ yr−1. We find that it falls short of the circumstellar density that would be needed to power the visual light curve of SN 2006gy by three orders of magnitude. That account for why we observe a relatively weak and soft (i.e. ...
... The mass-loss rate for the progenitor from x-ray data is about 5 × 10−4 M⊙ yr−1. We find that it falls short of the circumstellar density that would be needed to power the visual light curve of SN 2006gy by three orders of magnitude. That account for why we observe a relatively weak and soft (i.e. ...
Recipe for a Star
... The star is called a red giant because it is brightest in the red portion of the spectrum. Because the star’s diameter is larger, it is much brighter than it was as a normal star. Red giants may vary in size depending on their mass. An example of a red giant is the star called Aldebaran, in the cons ...
... The star is called a red giant because it is brightest in the red portion of the spectrum. Because the star’s diameter is larger, it is much brighter than it was as a normal star. Red giants may vary in size depending on their mass. An example of a red giant is the star called Aldebaran, in the cons ...
astronomy - Scioly.org
... used as the basis for apparent magnitude, although the near-infrared may also be used. A light curve may be used to plot an object’s apparent magnitude versus time. -Absolute magnitude (M) is the measure of the brightness of a celestial object at a distance of 10 parsecs away from the viewer. Absolu ...
... used as the basis for apparent magnitude, although the near-infrared may also be used. A light curve may be used to plot an object’s apparent magnitude versus time. -Absolute magnitude (M) is the measure of the brightness of a celestial object at a distance of 10 parsecs away from the viewer. Absolu ...
Bang To Sol - Transcript
... hydrogen and helium nuclei and the first atoms were formed. Suddenly, light could race thru the universe without bumping into charged particles and the universe became transparent and dark -- filled mostly with clouds of hydrogen and helium gas. The light released at that time is still visible today ...
... hydrogen and helium nuclei and the first atoms were formed. Suddenly, light could race thru the universe without bumping into charged particles and the universe became transparent and dark -- filled mostly with clouds of hydrogen and helium gas. The light released at that time is still visible today ...
Sec 29.3 - Highland High School
... It takes about 10 billion years for a star with the mass of the Sun to convert all of the hydrogen in its core into helium. Thus, such a star has a main-sequence lifetime of 10 billion years. From here, the next step in the life cycle of a small mass star is to become a red giantmoves out of the mai ...
... It takes about 10 billion years for a star with the mass of the Sun to convert all of the hydrogen in its core into helium. Thus, such a star has a main-sequence lifetime of 10 billion years. From here, the next step in the life cycle of a small mass star is to become a red giantmoves out of the mai ...
Lecture 17, PPT version
... Main sequence mass < 5 Msun: white dwarf Main sequence mass between 5 Msun and 40 Msun: neutron star Main sequence mass > 40 Msun: black hole ...
... Main sequence mass < 5 Msun: white dwarf Main sequence mass between 5 Msun and 40 Msun: neutron star Main sequence mass > 40 Msun: black hole ...
Shocking Truth about Massive Stars Lidia Oskinova Chandra’s First Decade of Discovery
... ’’A very energetic explosion of a massive star is likely to create a ... fireball.... the inner core of a massive, rapidly rotating star collapses into a ~10 M Kerr black hole ... A superstrong ~10 15 G magnetic field is needed to make the object ... a microquasar. Such events must be vary rare...to ...
... ’’A very energetic explosion of a massive star is likely to create a ... fireball.... the inner core of a massive, rapidly rotating star collapses into a ~10 M Kerr black hole ... A superstrong ~10 15 G magnetic field is needed to make the object ... a microquasar. Such events must be vary rare...to ...
Adapting Materials for ELL Students - title
... separates itself from the residual hydrogen and dust in the area. Over time, the cloud will then shrink in size as its core increases in temperature. If the nascent star's mass is sufficiently dense, the core will become so hot as to cause a nuclear reaction, in which case the body achieves stardom. ...
... separates itself from the residual hydrogen and dust in the area. Over time, the cloud will then shrink in size as its core increases in temperature. If the nascent star's mass is sufficiently dense, the core will become so hot as to cause a nuclear reaction, in which case the body achieves stardom. ...
the maximum mass of ideal white dwarfs
... where Μ/ equals the mass of the star in units of the sun. This formula was found to give a much better agreement with facts than the theory of E. C. Stoner,2 based also on Fermi-Dirac statistics but on uniform distribution of density in the star which is not quite justifiable. In this note it is pr ...
... where Μ/ equals the mass of the star in units of the sun. This formula was found to give a much better agreement with facts than the theory of E. C. Stoner,2 based also on Fermi-Dirac statistics but on uniform distribution of density in the star which is not quite justifiable. In this note it is pr ...
The Evolution of Stars - a More Detailed Picture (Chapter 8
... fall indefinitely. When the temperature of the outer layers of the star fall below a certain level, they become fully convective. This enables a greater luminosity to be carried by the outer layers and hence abruptly forces the evolutionary tracks of low-mass stars in the HR diagram to travel almost ...
... fall indefinitely. When the temperature of the outer layers of the star fall below a certain level, they become fully convective. This enables a greater luminosity to be carried by the outer layers and hence abruptly forces the evolutionary tracks of low-mass stars in the HR diagram to travel almost ...
lecture12
... A classification of the stellar black body For historical reasons, astronomers classify the temperatures of stars on a scale defined by spectral types, called O B A F G K M, ranging from the hottest (type O) to the coolest (type M) stars. ...
... A classification of the stellar black body For historical reasons, astronomers classify the temperatures of stars on a scale defined by spectral types, called O B A F G K M, ranging from the hottest (type O) to the coolest (type M) stars. ...
Microsoft Power Point version
... Lower mass main-sequence stars are also much more common than higher mass stars. ...
... Lower mass main-sequence stars are also much more common than higher mass stars. ...
![19 — Stellar Energy [Revision : 1.4]](http://s1.studyres.com/store/data/017867977_1-139820145cee69abc1dc516c7511cb2b-300x300.png)
19 — Stellar Energy [Revision : 1.4]
... – This is Kelvin-Helmholtz contraction: in a star with no other energy sources, luminosity is supplied by gravitational energy release (half goes into luminosity, other half goes into thermal energy) – Typical timescale of KH contraction: tKH ∼ ...
... – This is Kelvin-Helmholtz contraction: in a star with no other energy sources, luminosity is supplied by gravitational energy release (half goes into luminosity, other half goes into thermal energy) – Typical timescale of KH contraction: tKH ∼ ...
How Stars Work: Ay 122 - Fall 2004 - Lecture 7
... In the central regions of stars, OK to assume that all the elements are fully ionized. Denote abundances of different elements per unit mass by: • X hydrogen - mass mH, one electron • Y helium - mass 4mH, two electrons • Z the rest, `metals’, average mass AmH, approximately (A / 2) electrons per nuc ...
... In the central regions of stars, OK to assume that all the elements are fully ionized. Denote abundances of different elements per unit mass by: • X hydrogen - mass mH, one electron • Y helium - mass 4mH, two electrons • Z the rest, `metals’, average mass AmH, approximately (A / 2) electrons per nuc ...
Chapter 29: Stars - Mr. Pelton Science
... a cloud of interstellar dust and gas called a nebula. ...
... a cloud of interstellar dust and gas called a nebula. ...
Study Guide for the Final Astronomy Exam
... 10) Unit 61: Main Sequence Stars A) Be able to write down the mass, luminosity, radius, temperature, and lifetime in solar units of main sequence O, G and M stars. 11) Unit 62Giant Stars A) Describe how shell burning creates giant stars 12) Unit 64: Post-Main Sequence of the Sun (low mass stars) A) ...
... 10) Unit 61: Main Sequence Stars A) Be able to write down the mass, luminosity, radius, temperature, and lifetime in solar units of main sequence O, G and M stars. 11) Unit 62Giant Stars A) Describe how shell burning creates giant stars 12) Unit 64: Post-Main Sequence of the Sun (low mass stars) A) ...
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.