The Earth orbits the sun constantly, continuously, and all the time. " 24/7/365 "
From the sun's point of view, it takes the Earth roughly 365 and 1/4 days
to make the complete trip, all the way around one time. That's the length
of time that we call "one year".
When you talk about orbiting in one month, you're thinking of the moon
orbiting the Earth. THAT length of time is about 27.32 days.
Answer:
finding Cepheid variable and measuring their periods.
Explanation:
This method is called finding Cepheid variable and measuring their periods.
Cepheid variable is actually a type of star that has a radial pulsation having a varying brightness and diameter. This change in brightness is very well defined having a period and amplitude.
A potent clear link between the luminosity and pulsation period of a Cepheid variable developed Cepheids as an important determinants of cosmic criteria for scaling galactic and extra galactic distances. Henrietta Swan Leavitt revealed this robust feature of conventional Cepheid in 1908 after observing thousands of variable stars in the Magellanic Clouds. This in fact turn, by making comparisons its established luminosity to its measured brightness, allows one to evaluate the distance to the star.
I think it is c I'm only in 7th grade but I'm pretty sure that the answer is c