- #1
Thecla
- 132
- 10
Hi
When I was a kid, the largest telescope was Mt Palomar, a little over 5 meter diameter mirror. In spite of its large size, I always read that stars appeared as points of light through the scope if it were used visually, i.e. stars are too small and too distant to appear as disks.
However with the advent of very large telescopes(10 to 15 meters diameter)and the possibility of 40 meter telescopes in the future, I have a question:
How large a telescope is necessary to show a close star like Sirius as a small disk, approximately equal to the size of the planet Neptune as seen through a 4" telescope at medium power?
For calculation purposes assume this is a space-based telescope so there are no atmospheric interferences and also assume perfect optics
When I was a kid, the largest telescope was Mt Palomar, a little over 5 meter diameter mirror. In spite of its large size, I always read that stars appeared as points of light through the scope if it were used visually, i.e. stars are too small and too distant to appear as disks.
However with the advent of very large telescopes(10 to 15 meters diameter)and the possibility of 40 meter telescopes in the future, I have a question:
How large a telescope is necessary to show a close star like Sirius as a small disk, approximately equal to the size of the planet Neptune as seen through a 4" telescope at medium power?
For calculation purposes assume this is a space-based telescope so there are no atmospheric interferences and also assume perfect optics