I am having a hard time with these astronomy questions. Our teacher gives us no help and I am lost with this stuff. If anybody could help me out not just with the answer but on How to do it I would be most appreciative. What would be the frequency of an electromagnetic wave having a wavelength of 1.37 Earth's diameter (12,800 km) to the nearest Hz? The blackbody emission spectrum of one object peaks in the ultraviolet region of the spectrum at 185 nm. A second object's spectrum peaks in the red region at 650 nm. To two decimal places, according to Wien's law, how many times hotter is it? To one decimal place, in the previous problem, according to Stefan's law, how many times more energy per unit area does the hotter body radiate? If your body surface area is 1.98 m2, to the nearest watt, how much energy do you radiate to your environment per second? To the nearest hundredth of a micron, at what wavelength does a protostar with a temperature of 979 K radiate most strongly? Radiation from an approaching nearby star is observed to be reduced in wavelength (after correcting for Earth's orbital motion) by a factor of 0.999926. To the nearest tenth of a km/s, what is the radial velocity of the star relative to the Sun? Imagine you are observing a spacecraft orbiting a distant planet in an orbit with a radius of 100,000 km. You happen to be located in the plane of the spacecraft's orbit. You find that the spacecraft's radio signal varies periodically in wavelength between 3 + and - 0.000023 meters. Assuming the radio is broadcasting at constant frequency, to the nearest tenth of a MHz, what is that frequency? In the previous problem, what is the mass of the planet? Enter the answer in the form n.nneyy, which is "computer speak" for n.nn x 10yy, that is, 5.37 x 1020 should be entered as 5.37e20. If you can just help on one that would be great.