Satellites
The Moon is natural; others are man-made.
Moving specks
At night you see a tiny speck moving steadily across the sky. It is not a star.
What could it be?
What this lesson covers
The idea
The Moon is Earth's natural satellite, while artificial satellites are man-made objects orbiting Earth; most orbit about 800 km above the surface, taking roughly 100 minutes per orbit, and look like tiny moving specks at night.
Moving specks
At night you see a tiny speck moving steadily across the sky. It is not a star.
What could it be?
- An artificial satellite
- A moving star
- The Moon
Two satellites
Open both tabs.
Man-made moons
The Moon is Earth's natural satellite. Satellites sent up by various countries are artificial satellites. Most orbit about 800 km above the Earth's surface and take roughly 100 minutes to complete one orbit.
The Moon is a natural satellite. Artificial satellites are man-made. Most orbit about 800 km up and take about 100 minutes per orbit.
Notes
Artificial satellites are man-made, orbit ~800 km up, ~100 minutes per orbit.
Check yourself
The Moon is Earth's …
About how high above the Earth do most artificial satellites orbit, in km?
Answer: 800 km
Most orbit about 800 km above the surface.
About how many minutes does one orbit of most artificial satellites take?
Answer: 100 min
One orbit takes roughly 100 minutes.
At night, artificial satellites look like …
- natural satellite — correct. Yes!
- artificial satellite. The Moon is natural. Artificial satellites are man-made.
- star. The Moon is a natural satellite.
- big full Moons. They look like tiny specks.
- tiny moving specks — correct. Yes!
- lightning. They appear as tiny moving specks.