Stars - PowerPoint PPT Presentation

Loading...

PPT – Stars PowerPoint presentation | free to download - id: 650abd-ZWQyM



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Stars

Description:

Life Cycle Neutron Star- Large cores collapse in on themselves Supernova- Center of neutron star ... Core- The Sun's nuclear – PowerPoint PPT presentation

Number of Views:26
Avg rating:3.0/5.0
Date added: 26 February 2019
Slides: 36
Provided by: dantebo
Category:
Tags: star | stars

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Stars


1
Stars
  • Chapter 25

2
The Sun
  • The Suns mass controls the motions of the
    planets
  • Less dense than Earth
  • High pressure and temperature causes gases to be
    plasma

3
(No Transcript)
4
  • Fusion- Combining of nuclei to form a larger
    nucleus
  • Fission- Separation of large nucleus into smaller
    nuclei
  • The Sun uses fusion to combine Hydrogen into
    Helium

5
(No Transcript)
6
Anatomy of the Sun
  • 1. Core- The Sun's nuclear "furnace," where
    fusion reactions initially combine hydrogen atoms
    to produce helium, yielding energy in the
    process.

7
Anatomy of the Sun
  • 2. Radiative Zone. Energy moves through a
    surrounding envelope of gas toward the Sun's
    surface.

8
Anatomy of the Sun
  • 3. Convection Zone. Big "bubbles" of hot gas
    transport energy to the surface.

9
Solar Zones
  • Radiative Zone- 61 of interior from core. Heat
    moves directly to the surface
  • Convective Zone- 14 as heat moves to surface and
    cools, matter becomes more dense and sinks to be
    reheated

10
Anatomy of the Sun
  • 4.Photosphere- The Sun's visible surface. Because
    of its high temperature, it glows yellow.

11
  • Photosphere- lowest layer of the atmosphere
  • 400 Km thick
  • Visible surface

12
  • Chromosphere- second layer
  • 2500 KM thick
  • 30000 K
  • Normally not visible

13
Anatomy of the Sun
  • 7. Corona- The Sun's outer atmosphere, which is
    heated by the magnetic field to millions of
    degrees.

14
  • Corona- The outermost layer
  • Several million kilometers thick
  • 1 to 2 million degrees K
  • Low density

15
Solar Wind
  • Charged particles escaping from the corona
  • Reaches Earth at 400 km/s
  • Particles collide with atmospheric gases to form
    auroras

16
(No Transcript)
17
Solar Activity
  • Sunspots- Dark colored, cooler spots on the
    surface of the photosphere caused by magnetic
    fields
  • Coronal Holes- Low density gas areas of the
    corona usually over sunspots provide escape for
    solar wind

18
Solar Activity
  • Solar Flares- Eruptions of particles and
    radiation from the surface of the Sun can cause
    problems with Earths communication systems
  • Prominence- An arc of gas that is emitted from
    the chromosphere or condenses in the corona
    50000 K

19
Solar Activity Impact
  • Solar activity cycle lasts 22.4 years
  • 11.2 to maximum sunspots
  • 11.2 to minimum sunspots
  • Low sunspot activity cause a cooling of the
    Earths climate (Maunder Minimum)

20
Spectra
  • Visible light arranged by wavelength
  • Continuous- No breaks in the band
  • Absorption- Bands caused by chemicals in the
    atmosphere absorbing certain wavelengths
  • Emission- Bright lines from a gas at certain
    wavelengths

21
(No Transcript)
22
Star Groups
  • Constellations- groups of stars usually named
    animals, mythological characters, or everyday
    objects
  • Circumpolar- Orbit the poles and can be seen year
    round
  • Seasonal- Orbit equator and can only be seen
    during certain times of the year

23
(No Transcript)
24
Star Groups
  • Clusters- Group of stars that are gravitationally
    bound open or globular
  • Binaries- Two stars gravitationally bound
    together appear as one to the human eye. One is
    brighter than the other

25
(No Transcript)
26
Star Light, Star Bright
  • Apparent Magnitude- The brightness of a star to
    the naked eye, regardless of distance from Earth.
  • Absolute Magnitude- Brightness of stars measured
    at equal distances
  • Luminosity- Amount of energy per second put out
    by a star.

27
Star Measurement
  • Light Year- The distance the light will travel in
    a year 9.461 X 10¹² km
  • Parsec- 3.26 light years 3.086 X 10¹³ km
  • Parallax- Apparent shift in position caused by
    the motion of the observer

28
Star Classifications
  • O, B, A, F, G, K, M- Based on spectral lines and
    temperature
  • O has hottest temperature and fewest lines
  • M has coolest temperature and most lines
  • Each letter is divided into 9 numbered categories

29
Star Structure
  • 73 Hydrogen
  • 25 Helium
  • 2 Other

30
Life Cycle
  • Star Formation- Cloud of interstellar gas called
    a Nebula which forms a Protostar
  • Protostar becomes hot enough for fusion to begin
    and become a star

31
(No Transcript)
32
Life Cycle
  • Red Giant- Hydrogen is used up and star expands
    and cools gases start to escape
  • Core of red giant is hydrogen and convert to
    carbon
  • Star shrinks and becomes White Dwarf
  • White Dwarf does not require heat source to
    continue

33
(No Transcript)
34
Life Cycle
  • Neutron Star- Large cores collapse in on
    themselves
  • Supernova- Center of neutron star auses massive
    explosion blowing off the outer layers
  • Black Hole- Massive core that collapse in and
    with a gravitational field that sucks everything
    in.

35
(No Transcript)
About PowerShow.com