From the surface of the Earth under very good conditions, we can resolve an angular size...
Suppose you wanted to build a telescope capable of resolving a planet the size of Earth that is 17 light-years away. a. Calculate the angular diameter of Earth if it were that far. To see any detail on the surface, we would want to see an angular size about ten times smaller than this. b. Calculate the diameter of a telescope that would be needed to resolve this angular size if observing at 592 nm. Is this feasible?
The telescopes on some commercial surveillance satellites can resolve objects on the ground as small as 91 cm across (see Google Earth), and the telescopes on military surveillance satellites reportedly can resolve objects as small as 14 cm across. Assume first that object resolution is determined entirely by Rayleigh's criterion and is not degraded by turbulence in the atmosphere. Also assume that the satellites are at a typical altitude of 403 km and that the wavelength of visible light is...
very optical device has an angular resolution, the smallest angle over which it allows us to tell if two dots -- or two stars -- are distinct. If two stars have an angular separation less than the angular resolution, they appear as as a single object. This limited angular resolution can arise for a number of reasons: quality of the optics, blurring of the atmosphere and quantum mechanics. For example, from the ground on Earth, due to the blurring of...
Today, the Moon’s orbit around Earth has a semi-major axis of a=384,400 km and an orbital period of 27.32166 days. a. The Moon slowly moves outward due to tidal braking of the Earth’s rotation, and at some future date the Moon will have an orbital period of 47 days. Compute the semi-major axis of the Moon’s orbit at this future date (express your answer in kilometers). semi-major axis = 5.5*10^5 km b. Today, the Moon has an angular diameter of...
I need (c) and (d) answered 3 Satellite There are claims that a spy satellite can read license plate numbers from space or read a newspaper over your shoulder. In this problem, we will assess these claims using wave optics. (a) Reading a licence plate number requires a linear resolution of about 5 cm. (You must be able to distinguish objects that are 2 inches apart.) For a satellite at a height of 150 km, what angular resolution does this...