Why do telescopes need to track objects?

Answer 1

-- Please go outside tonight. If the sky is cloudy, go back inside and forget the

whole thing. If the sky is clear, stay outside, look up, and go on to the next step.

-- If the moon happens to be up, look at the moon and remember kind of where it is.

-- Also find one star that you think you could find again from the patterns of the other stars

around it. Remember kind of where it is.

-- Go inside for a little while. Watch some TV, read the paper, have a cookie and a

glass of milk.

A half-hour or 45 minutes ought to be enough to make the point I'm trying to make

in answer to your question.

-- Go back outside. Find the Moon again. Find the star again.

-- If you wanted to watch the Moon through your telescope for 45 minutes, how

would you do that ?

-- If you wanted to photograph that star through your telescope, with an exposure time

of 3 hours (very common), how would you do that ?

Everything in the sky appears to move ... by roughly the diameter of the full moon every two minutes !

That's why any serious observer or researcher needs to have his telescope follow the objects

he's trying to observe.

Have you noticed how the sun rises on one side of the sky, completely crosses it, and

sets all the way over on the other side 12 hours later ?

Answer 2

to keep it sturdy