Earth, Moon and Sun Flashcards
What is at the centre of the solar system?
The Sun.
What is the diameter of the Earth?
13,000 km (average). Flattened slightly at the poles (by 42 km).
What is the shape of the Earth?
Oblate spheroid.
How long does it take the Earth to rotate once on its axis?
23 hours 56 minutes.
How long does it take the earth to rotate through 1 degree?
4 minutes.
What is the Moons orbital and rotational period?
27.3 days.
What is the diameter of the Moon?
3,500km. Quarter of Earth’s diameter.
What is the average distance to the Moon from the Earth?
380,000 km.
What are the three features that distinguish the Earth from other planets?
Atmosphere, Water and Life.
Give six pieces of evidence to suggest the Earth is not flat.
- Ships disappear below the horizon.
- Satellites orbit the earth (impossible if Earth was flat).
- The curvature of the Earth’s shadow during a partial lunar eclipse.
- Aircraft fly in arcs rather than straight lines ( because this is the shortest distance on a curved earth).
- Images of Earth from space.
- Eratosthenes (because shadows of an object at the same time of day should be the same if earth was flat).
What *is the angle between a point on the Earth’s surface, the centre of the Earth and the equator. It is expressed as an angle in o North or South of the Equator.
Latitude.
Describe the Earth’s polar axis.
Tilted by 66.5° to the plane of the ecliptic.
Tilt of the earth’s axis is 23.5° from the perpendicular to the ecliptic.
What the name given to the plane on which the Earth orbits the Sun?
Ecliptic.
What is the name of the *imaginary North to South line running directly through the observer’s zenith.
Meridian.
What is the name given to the *angular displacement East or west of the observer’s meridian from the Prime Meridian (that passes through Greenwich).
Longitude.
