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Alien Worlds

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KS3 Physics / Motion and forces / Describing motion / speed = distance รท time
KS4 Physics / Forces and motion / Estimating speeds
KS4 Physics / Space physics / the main features of the solar system

The solar system is huge, and the Universe even bigger! Using current technology, it takes a long time to get from Earth to another planet. Your first task is to calculate how far you would have to travel, on average, if you could travel in a straight line from Earth to the other planets in our solar system.
Use the Activity Sheet that has a table containing the distances of the different planets from the Sun.

Task 1:

Write an equation for determining the distance Mercury is from Earth:

Write an equation for determining the distance Jupiter is from Earth:


Task 2:

The NASA Parker Solar Probe became the fastest ever man-made object in 2018. It can travel at 365,000 kilometres per hour. This is a lot faster than the speeds we are used to travelling at here on Earth, but still not as fast as the speed of light (~1,079,000,000 km/h).

Using your calculated distances from above, calculate the length of time (in hours) it would take you if you were walking, riding a bike, driving a car, riding the Parker Solar Probe, or travelling at the speed of light.

Write an equation for determining travel time, t: