the sky l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
The Sky PowerPoint Presentation
Download Presentation
The Sky

Loading in 2 Seconds...

play fullscreen
1 / 18

The Sky - PowerPoint PPT Presentation


  • 698 Views
  • Uploaded on

The Sky The Sky Constellations - Patterns of stars There are 88 constellations in the night time sky. The Sky The Greek alphabet is used to signify the brightness of a star in a constellation

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'The Sky' - benjamin


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
the sky2
The Sky
  • Constellations - Patterns of stars
  • There are 88 constellations in the night time sky.
the sky3
The Sky
  • The Greek alphabet is used to signify the brightness of a star in a constellation
  • Betelgeuse (Beetle Juice) appears to be the brightest star in the constellation Orion. We would label Betelgeuse alpha Orionis, or  Orionis.
the sky4
The Sky

North celestial pole - points to

Polaris, the north star.

  • Celestial sphere – model of the sky above us
  • The ecliptic is the path the sun takes in the sky.
  • The highest point on the ecliptic the sun reaches is the summer solstice. The lowest point is the winter solstice.

Stars are on the surface

of the sphere.

Ecliptic

Celestial equator

South celestial pole

the sky5
The Sky
  • The summer solstice occurs on June 21 and is, in the northern hemisphere, the day with the longest amount of daylight.
  • The winter solstice occurs on December 21 and is the day with the shortest amount of daylight.

Summer solstice

Winter

solstice

the sky6
The Sky

Autumnal equinox

  • The equinoxes occur at the intersection points between the ecliptic and the celestial equator. Both days have equal light and darkness.
  • Vernal equinox occurs in the spring on March 21
  • Autumnal equinox occurs in the fall on September 21

0h, 0min

Vernal equinox

the sky7
The Sky
  • Constellations that fall on the ecliptic are called the signs of the Zodiac.
  •  We recognize 12 but there are actually 13 constellations that fall on the ecliptic.
  •  The thirteenth constellation on the zodiac is Ophiuchus (o fee' a cus)
the sky8
The Sky
  • Precession is the slow change in direction of the Earth’s rotation axis due to its spin.
  • The Earth is a very precise natural top.
  • Circumpolar constellations are those constellations that never rise or set.
the sky9

Declination

Right ascension

The Sky
  • We can find constellations on the celestial sphere by using coordinates. We use right ascension and declination.
  • Right ascension is measured in hours, minutes and seconds. The Earth rotates through 360 degrees in 24 hours.
  • Declination is measured in degrees from the equator.
  • The notation is as follows:

RA = 4h33m (right ascension)

dec = 724' (declination)

the sky10

Lines of Declination

90°

Lines of Right ascension

45°

30°

15°

22h0m

1h0m

-15°

23h0m

0h0m

Declination

-90°

The Sky
the sky11
The Sky
  • Seasons occur because the Earth is tilted 23 1/2°.
  • The Earth is closest to the Sun in January.
  • The Earth is farthest from the Sun in July.
  • The distance to the Sun does not determine the seasons.
the cycles of the moon
The Cycles of the Moon
  • Phases of the Moon
    • Waxing phases
      • Crescent
      • Quarter
      • Gibbous
    • Waning phases
      • Crescent
      • Quarter
      • Gibbous
  • Full moon
  • New moon
the cycles of the moon13
The Cycles of the Moon
  • Tides
    • 2 High tides per day
    • 2 Low tides per day
the cycles of the moon16
The Cycles of the Moon
  • Inner shadow is the umbra
  • Outer shadow is the penumbra
the cycles of the moon17
The Cycles of the Moon
  • Lunar eclipses
    • Total
      • Coppery in color
    • Partial
      • Partially in umbra
the cycles of the moon18
The Cycles of the Moon
  • Solar Eclipses
    • Total
      • Umbra
      • Diamond ring effect
    • Partial
      • Partially in umbra
    • Annular
      • penumbra