Pathways to Astronomy

Stephen E. Schneider

Chapter 40 Mars - all with Video Answers

Educators

Chapter Questions

Problem 1

Mars's orbit is quite elliptical, so at different times when it is in opposition, its distance from Earth can vary substantially. From the data given in this chapter, estimate the largest and smallest distance to Mars at opposition and when it is on the far side of the Sun. Assume that the Earth's orbit is circular at 1 AU.

Eric Mockensturm

Numerade Educator

00:59

Problem 2

How long would it take an electromagnetic signal sent from Earth to reach a spacecraft on Mars, for each of the distances you calculated in problem $1 ?$

James Irizarry

Numerade Educator

01:07

Problem 3

From the surface of Earth under very good conditions, we can resolve an angular size of about 1 arc second. When Mars is $0.5 \mathrm{AU}$ away, calculate the linear size (in kilometers) of a feature on the surface that would appear to be 1 arc second across. The Hubble Space Telescope can resolve about 0.04 arc seconds; what size on Mars does this correspond to?

Tyler Moulton

Numerade Educator

04:03

Problem 4

What angular size would Phobos and Deimos have as viewed from the surface of Mars? Could either produce a solar eclipse?

Daniel Alva

Numerade Educator

04:53

Problem 5

Earth's atmospheric pressure drops by about a factor of 2 every $5 \mathrm{km}$ higher up you go, so it is one-fourth the surface pressure at $10 \mathrm{km}$, for example. How high up in Earth's atmosphere would you have to go to reach a pressure similar to the $0.6 \%$ atmospheric pressure on Mars? (You can do this mathematically with logarithms or plot the changing pressure with elevation and estimate the height where this pressure is reached.)

Romaila Saud

Numerade Educator

01:17

Problem 6

The average surface pressure on Mars is almost exactly equal to that below which water cannot be liquid. Review the topographic map of Mars in Figure $40.3 .$ If you wanted to search an area that had the greatest probability of any location on Mars for liquid water today, where would you go and why?

Zachary Warner

Numerade Educator