1. Why is life difficult to define?
Reason it is difficult to define life is the lack of objective measuring tools. All of our human
methods for defining the undefinable science, philosophy, religion, metaphysics are self-limiti
PHYS 1403.NT Stars & Galaxies
Lab Assignment 8
Refractor Telescopes - The refractor telescope uses a lens to gather and focus light. The first
telescopes built were refractors. The small telescopes sold in department stores are refract
1. Give a brief description of the interstellar medium.
The matter between stars, composed of two components, gas and dust, intermixed throughout all
2. What is the composition of interstellar gas?
Made up od individual
1. Briefly describe the basic chain of events leading to the formation of a star like our
Stage one is an interstellar cloud, stage two is a collapsing cloud fragment, third the
fragmentation ceases, fourth is a protostar, fi
1. What is the cosmological principle?
is the notion that the distribution of matter in the universe is homogeneous and
isotropic when viewed on a large enough scale, since the forces are expected to
act uniformly throughout the
1. Name two basic differences between normal galaxies and active galaxies.
The luminosities of active galaxies are extremely large and their spectra differ slightly. Also,
their energy emission is mostly nonstellar.
1. What are spiral nebulae?
A galaxy that consist of a flat, rotating disk containing stars, gas, and dust.
2. Contrast the motion of disk and halo stars.
Disk stars move in a circular motion and halo stars are more eccentric so t
1. What are X-rays bursters?
Class of x-ray binary stars exhibiting periodic and rapid increases in luminosity.
2. What is an Event horizon?
A boundary around a black hole where no light or other radiation can escape.
3. What is t
1. Describe the basic properties of the main types of normal galaxies.
spiral and barred spiral, elliptical and irregular are the basic types of galaxies and most galaxies
fall in to this category.
2. What is the Virgo Cluster?
The Virgo Clu
1. What is a light curve?
Light curves are graphs that show the brightness of an object over a period of time.
2. What is a parsec?
A unit of distance equal to about 30 trillion kilometers.
3. What are stellar luminosities?
1. What is hydrostatic equilibrium?
The flow of velocity is constant at each point over time.
2. What makes an ordinary star become a red giant?
When the star is no longer in a stable equilibrium the core is unbalanced making hydr
1. What is an accretion disk?
A rotating disk of matter formed by accretion around a massive body under gravitation.
2. What is neutron degeneracy pressure?
A stellar application of paul exclusion principle where No 2 neutrons can
1. Summarize the overall properties of the Sun.
The Sun is the sole source of light and heat for the maintenance of life on Earth. It is a star, a
glowing ball of gas held together by its own gravity and powered by nuclear fusion at
PHYS 1403.NT Stars & Galaxies
Final Exam S&G
1. Explain how observations of the Sun's core challenge our present
understanding of fundamental physics.
A: What is known about the suns interior comes from models that use the laws of
Lets begin with what even is SOHO. SOHO which is abbreviated for the meaning Solar and
Heliospheric Observatory, is a project NASA and ESA launched back in the winter of 1995 help
us understand more about how the sun from the dee
Homework Assignment #1
PHYS 1403.NT.16S1 Stars & Galaxies
1. Name and briefly describe the main regions of the Sun.
The main regions of the Sun are the chromosphere, the transition zone, and the solar corona.
Just above the photosphere is