Question

1.) At what distance would a satellite orbiting the Earth be geosynchronous (orbiting the Earth once every 24 hours)?

It would be geosynchronous at _________ × 10⁴ m from the center of the Earth or __________× 10⁴ m from the Earth's surface.

2.) Hydrogen also produces spectral lines at radio wavelengths, notably at 21.1 cm. If a galaxy is moving away from us at 9% of the speed of light, at what wavelength will we detect this line? Convert this into frequency.

We will detect this line at wavelength λ = _________ cm.

The frequency is v = __________ × 10⁹ Hz or  GHz.

3.) Suppose you wanted to build a telescope capable of resolving a planet the size of Earth that is 20 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 580 nm. Is this feasible?

------->>>>>a. The angular diameter is ______________× 10^-9 degree.

--------->>>>>b. The diameter of the telescope would have to be D = ________ k

Answer 1