Satellite images

Question 1

Define Satellite

Answer 1

Human-made object put into orbit in space.

Question 2

Define Atmosphere

Answer 2

The layer of gases surrounding the Earth.

Question 3

Satellite image

Answer 3

A satellite image is an image taken from a satellite. Satellites travel around the Earth, above the atmosphere, in a path called an orbit.

Some satellites have cameras that continuously take images of the Earth’s surface. The images are sent back to earth digitally.

Question 4

Information from satellite images?

Answer 4

Landsat 7 is the satellite that provides us, in South Africa, with daily images of the Earth’s surface.

This satellite was launched by the United States as part of their NASA programme. It has been orbiting Earth since July 1999.

Question 5

Information obtained from satellite images?

Answer 5

· Vegetation cover
· Soil moisture content
· Soil erosion
· Settlement
· Water and wetlands

It can also give weather forecasters the information they need, by providing data on cloud patterns.

Question 6

How satellite images are used?

Answer 6

The satellite can take images of the same area on the Earth’s surface every day as it passes in its orbit.

This means we can compare the images and record changes such as:
· The extent of flooding and recovery from floods
· The loss of vegetation in an area
· The increase in an area taken up by settlements

On a satellite image, black areas are water, dark areas are mountains and other shades such as blue show settlement and red show vegetation.