As Earth revolves around the Sun, how does its axis of rotation change relative to the Sun? How does this affect the seasons?
Answers
ANSWER:-
In 1610, Galileo turned his new telescope toward Venus. To his amazement, he saw the planet pass through phases just like the Moon. Galileo correctly surmised that this could happen only if Venus had an orbit closer to the Sun than Earth’s orbit.
With improved telescopes, astronomers started looking for another proof of Earth’s motion around the Sun, stellar parallax. Earth’s orbit is huge — some 186 million miles (300,000 kilometers) in diameter. If an astronomer measures the position of a nearby star, and then measures it again six months later, the star’s apparent position against the background of more distant stars should shift a tiny amount.
Observing this would prove that Earth in fact is not stationary. It wasn’t until 1838 that an astronomer finally detected this shift. That year, German astronomer Friedrich Wilhelm Bessel successfully measured the parallax of the star 61 Cygni.