Exam 10: Characterizing Stars

What is the ratio of the light energy that falls on a unit area of Mercury's surface compared to that falling on a unit area of Earth's Moon if Mercury is at 0.4 AU and the Moon is at 1.0 AU from the Sun?

Which statement about measuring the mass of an isolated star (a star that is not in a binary star system)is CORRECT?

Who was the first person to measure the parallax of a star successfully?

The object you are observing through a telescope appears visually to be a single star,but you know by looking at its spectrum that it is a binary system.Which spectral feature might NOT characterize it as a binary?

The process of evolution of stars in our universe has been interpreted by:

In what fundamental way do we (and many other animals)utilize parallax for the measurement of distance?

Classifying stars by spectral type is the same as categorizing them by:

Stellar parallax as small as 0.01 arcsec can be measured using telescopes on Earth.To what distance does this measurement correspond in space?

The star β Phoenicis has an apparent magnitude of +3.4 and an absolute magnitude of -4.6.The North Star (Polaris)has an apparent magnitude of +2.0 and an absolute magnitude of -4.6.Assuming that no light has been absorbed or scattered by interstellar dust,we can say for sure that Polaris is:

An eclipsing binary system consists of:

What fraction of the stars surrounding the Sun are main-sequence stars?

The triple-star system α Centauri has a parallax of 0.75 arcsec (the largest parallax known).How far is this star system from the Sun in light-years? (Careful with units!)

The MOST accurate stellar parallax measurements for distances to the majority of stars in our neighborhood of the universe have been made by:

Viewed from Earth,the Sun's absolute magnitude is M = 4.8 and its apparent magnitude is m = -26.7.Viewed from Neptune,30 AU from the Sun,the Sun's apparent magnitude is:

One important aspect of the study of binary star systems,as distinct from single stars,is that it provides a:

An eclipsing binary system consists of:

What particular and very important phenomenon frequently occurs in binary star systems where the stars are very close together?

Which spectral classification signifies the coolest stellar surface temperature?

The relative brightness of a star as we see it in Earth's sky is called:

A typical white dwarf has a surface temperature about four times that of the Sun and a radius about 1% that of the Sun.What can you determine about the luminosity of a typical white dwarf from this information?