Use the following questions to check your understanding of some of the many types of visual information used in astronomy. For additional practice, try the Chapter 9 Visual Quiz at Mastering Astronomy.
The image from a MESSENGER flyby shows evidence of impact catering, volcanism, and tectonic activity on Mercury. Answer the following questions based on the image. Remember that craters are bowl-shaped and rough-floored when they form, and wipe out any preexisting features in the area. Lava on Mercury appears to be fairly runny and makes flat smooth plains as it spreads out.
2. The region around 2b has far fewer craters than the region around 2c. The crater floor at 2a is also flat and smooth, without many smaller craters on it. Why are regions 2a and 2b so smooth?
a. Few small craters ever formed in these regions.
b. Erosion erased craters that once existed in these regions.
c. Lava flows covered craters that once existed in these regions.
Want to see the full answer?
Check out a sample textbook solutionChapter 9 Solutions
COMS.PERS.SOLAR SYSTEM ASTR 2 PKG
- In the photo shown here, astronaut Alan Bean works at the Apollo 12 lander. Describe the horizon and the surface you see. What kind of terrain did they land on for this, the second human Moon landing, and why?arrow_forwardOne source of information about Mars has been the analysis of meteorites from Mars. Since no samples from Mars have ever been returned to Earth from any of the missions we sent there, how do we know these meteorites are from Mars? What information have they revealed about Mars?arrow_forwardWhat are the advantages of using radar imaging rather than ordinary cameras to study the topography of Venus? What are the relative advantages of these two approaches to mapping Earth or Mars?arrow_forward
- Look at the map of the Hawaiian chain of islands on the right-hand page of the Concept Art: Volcanoes. Which island formed most recently? How do you know? Is the newly formed volcano of a type found on Venus, on Mars, on both planets, or on neither?arrow_forwardWe believe that all of the terrestrial planets had similar histories when it comes to impacts from space. Explain how this idea can be used to date the formation of the martian highlands, the martian basins, and the Tharsis volcanoes. How certain are the ages derived for these features (in other words, how do we check the ages we derive from this method)?arrow_forwardIf, in the remote future, we establish a base on Mercury, keeping track of time will be a challenge. Discuss how to define a year on Mercury, and the two ways to define a day. Can you come up with ways that humans raised on Earth might deal with time cycles on Mercury?arrow_forward
- Describe the current atmosphere on Mars. What evidence suggests that it must have been different in the past?arrow_forwardWhy is it not surprising that there is no evidence of plate tectonics on Mercurys surface?arrow_forwardIf the Viking missions were such a rich source of information about Mars, why have we sent the Pathfinder, Global Surveyor, and other more recent spacecraft to Mars? Make a list of questions about Mars that still puzzle astronomers.arrow_forward
- Which of the five Terrestrial worlds have bow shocks, magneto-spheres, and radiation belts? How do you know?arrow_forwardWhy isnt the crust of Mars broken into mobile plates as Earths crust is? How do you know?arrow_forwardIf all life were destroyed on Earth by a large impact, would new life eventually form to take its place? Explain how conditions would have to change for life to start again on our planet.arrow_forward
- Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax