The first step towards getting somewhere is to decide you are not
... The first step towards getting somewhere is to decide you are not going to stay where you are. ...
... The first step towards getting somewhere is to decide you are not going to stay where you are. ...
Space Science Review ppt File
... down will be able to send a “shooter” to the the line to shoot for ...
... down will be able to send a “shooter” to the the line to shoot for ...
Educator`s Guide for Dark Star Adventure
... Bright Stars Tonight Star Colors We usually think of stars as twinkling white, but if we look carefully we can actually find stars of several colors. A star’s color is based on its temperature. A very cool star is dull red in color. As stellar temperatures increase the colors change from red to ora ...
... Bright Stars Tonight Star Colors We usually think of stars as twinkling white, but if we look carefully we can actually find stars of several colors. A star’s color is based on its temperature. A very cool star is dull red in color. As stellar temperatures increase the colors change from red to ora ...
lecture_1_mbu - X-ray and Observational Astronomy Group
... Photons scatter many times, take approx 105 years to reach interface layer. Density falls from 20 g/cm3 to 0.2 g/cm3, T falls from 7x106 K to 2x106 K over same distance. Tachocline (interface layer) : Lies between radiative zone and convection zone. Thought to be site of magnetic field generation. S ...
... Photons scatter many times, take approx 105 years to reach interface layer. Density falls from 20 g/cm3 to 0.2 g/cm3, T falls from 7x106 K to 2x106 K over same distance. Tachocline (interface layer) : Lies between radiative zone and convection zone. Thought to be site of magnetic field generation. S ...
Bayesian mass and age estimates for transiting exoplanet host stars⋆
... and metallicity used for many grids of stellar models can produce poor sampling of the observed parameter spacing, i.e., the typical difference in stellar density between adjacent model grid points can be much larger than the uncertainty on the observed value. This can produce systematic errors due t ...
... and metallicity used for many grids of stellar models can produce poor sampling of the observed parameter spacing, i.e., the typical difference in stellar density between adjacent model grid points can be much larger than the uncertainty on the observed value. This can produce systematic errors due t ...
Slide 1
... But what if we have an even bigger core? With enough pressure, we can FORCE atoms to let their electrons overlap. This happens for stars with cores up to 3 times heavier than the sun. This is the case with neutron stars. When a big core dies, gravity crushes down, but it crushes even harder than ele ...
... But what if we have an even bigger core? With enough pressure, we can FORCE atoms to let their electrons overlap. This happens for stars with cores up to 3 times heavier than the sun. This is the case with neutron stars. When a big core dies, gravity crushes down, but it crushes even harder than ele ...
PowerPoint Presentation - The Sun as a Power House
... Fusion would be simpler if four protons would collide simultaneously to make one helium nucleus Simpler, but less likely rare for four objects to collide simultaneously with high enough energy chance of this happening are very, very small rate too slow to power the Sun proton-proton chain: each step ...
... Fusion would be simpler if four protons would collide simultaneously to make one helium nucleus Simpler, but less likely rare for four objects to collide simultaneously with high enough energy chance of this happening are very, very small rate too slow to power the Sun proton-proton chain: each step ...
Counter-rotating Stellar Components in Simulated Disk Galaxies
... angular momentum Jz and the angular momentum of the circular orbit with the same binding energy Jcirc(E) This distribution for all star particles inside a sphere of radius 30 kpc has 2 peaks: one at c=+1.0 and the other one at c=-0.5 ...
... angular momentum Jz and the angular momentum of the circular orbit with the same binding energy Jcirc(E) This distribution for all star particles inside a sphere of radius 30 kpc has 2 peaks: one at c=+1.0 and the other one at c=-0.5 ...
BASIC PROPERTIES of STARS - 2
... Venus is about 105,000,000 km from the Sun. (1) What is approximate time to get the return signal from Venus when it is at its closest to Earth? C = 3 x 105 km/s (A 150; B 200; C 300; D 400 seconds) (2) What is the approximate time to get a return signal from Venus when Venus is at its most distant ...
... Venus is about 105,000,000 km from the Sun. (1) What is approximate time to get the return signal from Venus when it is at its closest to Earth? C = 3 x 105 km/s (A 150; B 200; C 300; D 400 seconds) (2) What is the approximate time to get a return signal from Venus when Venus is at its most distant ...
Gamma Ray Bursts: The biggest bang since the big one!
... • Cook until all hydrogen fuel eventually exhausted. ...
... • Cook until all hydrogen fuel eventually exhausted. ...
AS 701 - INTRODUCTION TO ASTROPHYSICS COURSE OVERVIEW - FALL 2013
... and gravitational physics, properties of stars, stellar structure, stellar evolution, dynamics of binary stars systems and star clusters, types of galaxies, galactic structure and dynamics, active galaxies and some cosmological topics. COURSE STRUCTURE AND PHILOSOPHY: The course is intended to provi ...
... and gravitational physics, properties of stars, stellar structure, stellar evolution, dynamics of binary stars systems and star clusters, types of galaxies, galactic structure and dynamics, active galaxies and some cosmological topics. COURSE STRUCTURE AND PHILOSOPHY: The course is intended to provi ...
Gamma Ray Bursts
... Scientists think it could come from the collisions of two very dense objects, such as neutron stars in a binary. Also, some think, they could be from the same process as the long GRB but were not directly along the axis of the emission, i.e. not seeing it face on. ...
... Scientists think it could come from the collisions of two very dense objects, such as neutron stars in a binary. Also, some think, they could be from the same process as the long GRB but were not directly along the axis of the emission, i.e. not seeing it face on. ...
EARTH & SPACE SCIENCE
... Nuclear fusion is the process by which nuclei of small atoms combine to form a new, more massive nucleus; the process releases energy Nuclear fusion occurs inside the sun. Nuclei of hydrogen atoms are the primary fuel for the sun’s fusion. Nuclear fusion produces most of the suns’ energy and con ...
... Nuclear fusion is the process by which nuclei of small atoms combine to form a new, more massive nucleus; the process releases energy Nuclear fusion occurs inside the sun. Nuclei of hydrogen atoms are the primary fuel for the sun’s fusion. Nuclear fusion produces most of the suns’ energy and con ...
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.