Here is our incredible solar system which has fascinated humans for all time:
In our solar system, some planets ORBIT nearer the Sun than Earth, and some planets ORBIT further away from the Sun than Earth.
The time it takes for a planet to travel once around the Sun is called a YEAR. Planets further away from the Sun have longer years because it takes longer to travel the distance. Have a think about that.
Planets spin at different speeds to the Earth, so their days are not 24 hours. (Venus has a day which lasts 243 Earth days!). Have a longer think about that!
Does that mean that on Venus your birthday is always tomorrow?! Let's have a look at our solar system....