Seasonal Stars

Demonstrate an understanding that some constellations are visible from a given latitude throughout the year, but others are seasonal.

If you lived at the Poles you would see the same stars throughout the year. However in the UK (between latitudes 50 and 60 degrees north) we see circumpolar constellations, such as Ursa Major througout the year and some constellations, such as Orion, for a few months of the year.

This is due to the seaons on Earth. The Earth's axis is titled at an angle of 23.5 degrees to the ecliptic. This results in us seeing some constellations throughout the year and some only part of the year. The amount of daylight also has an important part to play in this.

Orion is visible from October to February in the night sky. It is in the sky in June but we can't see when it rises as it is daylight. By the time evening comes it is set whereas Ursa Major has not set, it is visible in the night sky.

 

Questions

When seen from a location on Earth, explain how some constellations are:

  1. Visible throughout the year in the night sky
  2. Visible at certain times of year
  3. Not visible
Animation
Links

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