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Kepler’s Second Law. Because Earth’s orbit slightly elliptical, it’s sometimes a little closer to the Sun and sometimes a little farther away. This also means that it speeds up and slows down each year. It travels the fastest when it is

Select all types of light that transmit (pass) through Earth’s atmosphere and reach the ground:

In the Lyman series of hydrogen electron energy transitions, the lower energy state is the ground state (n= 1). If the upper state is the second excited state (n= 3), this produces a line called ‘Lyman beta’ whose transition is depicted in Figure 2. In the Balmer series of hydrogen electron energy transitions, the lower energy state is the first excited state (n = 2). If the upper state is the second excited state (n = 3), this produces a line called ‘Balmer alpha’ whose transition is also depicted in Figure 2. Which of the following statements are true about these two lines? Choose all that apply.

The type of electromagnetic radiation that travels the fastest is:

Convert 773 kilometers (km) into meters (m). There are 1000 m in 1 km. Show your work and include units. Express your answer in scientific notation.

A cold intergalactic gas cloud is located between Earth and a distant quasar (an extremely bright galaxy). If we take a spectrum of the background quasar, what would we look for to detect the gas cloud?

Which transition depicted in Figure 2 (above) corresponds with a higher energy?

We know that flux, or the brightness of light, follows an inverse square law, where it decreases by a factor of 1/d2. What else follows an inverse square law?

Which of these sizes is the largest?

Our Cosmic Address. Describe in your own words where we are in the Universe, starting with our planet Earth. Pretend you are describing our cosmic address to a relative or friend, using complete sentences.