Astronomy Exam 2

On continuous observation of a star, it is noted that the wavelengths of the dark lines in its absorption spectrum appear shortened. What is the most logical conclusion to make here?

The star is approaching Earth.

Why is an absorption spectrum especially useful for astronomers?

It has dark lines in it that allow astronomers to determine what elements are in the star

Star A has a temperature of 15,000 K and Star B has a temperature of 5,000 K. The two stars are the same distance from Earth and have the same size. How much more luminous is Star A compared to Star B? (4 times)

81 times

The absorption lines in the visible portion of the spectrum of a star that are produced by hydrogen are from the…

Balmer series

You are standing near a railroad track and a train is moving toward you at 60 mph and blowing its horn. What will you notice as the train moves past you?

As the train approaches, the horn will sound higher in pitch than when the train is moving away.

Electromagnetic radiation with the shortest wavelengths is categorized as _____.

Gamma rays

Which of the following has the lowest frequency or lowest energy?

Radio waves

Radio waves travel through space at what speed?

At the speed of light

When the diameter of one telescope is twice that of another, how does its collecting area compare?

Four times the area

The technique of connecting multiple telescopes together to combine the images from each telescope is known as…

interferometry

Newtonian focus telescopes use _____ to collect light.

Mirrors

What process causes light to be spread into a spectrum?

Dispersion

In a false color image…

Colors can represent photon energies or the intensity of electromagnetic radiation.

The Chandra X-Ray Observatory must operate in space because…

X rays do not penetrate Earth's atmosphere.

Substantial objects, resembling asteroids in size and composition, which built up early in the development of the solar system are referred to as…

planetesimals

What are the dwarf planets?

Eris, Pluto, Haumea, Makemake

The smaller objects in the solar system made of rock and metal (most of which orbit between Jupiter and Mars) are called:

asteroids

How many stars are there in our Solar System?

One

Which planet has the highest average density?

Mercury

Highest to Lowest Density in order:

Earth, Mercury, Venus, Mars, Neptune, Jupiter, Uranus, Saturn

If we cool down a balloon to 77 K with liquid nitrogen,  the pressure inside the balloon will___and the volume of the balloon will ___.                               .

decrease, decrease

The elusive neutrino that was suggested by physicist Wolfgang Pauli as carrying away the missing energy in certain types of nuclear reactions was not detected until 1956 because:

neutrinos interact very weakly with other matter.

The hottest part of the Sun is

The core

In the ___, photons take approximately between 100,000 to 1,000,000 years to "random walk" towards the surface of the Sun.

radiative zone

The Sun is so hot that all of the material in it is in the form of an ionized gas, called a(n):

plasma

The study of solar oscillations (back-and forth motions) are referred to as___.

helioseismology