Halley's Comet returns to the part of its orbit visible from Earth.
a persons birthday on the day of a leap year
The letter "Y."
The letter M.
every 102 years
Simple. Being born on a leap year on the 29th of February. As the 29th of February only occurs once every four years, you would have to live for 400 years to actually have your 100th birthday.
Jacob Jackson
Halleys Comet
Halley's Comet
the curiosity rover went into space eightand a half months ago so the curiosity rover will stay ther for two years straghit!:)
Every 4 years
every two years
4 years 4 yearsThe Summer Olympics are held once every 4 years.
every 4 years
no, 4 years
vicennial
4 years.
no it occurs in every 4 years