Mars Answers Document PDF

**General Characteristics** 1. **Why is Mars red?**\ Mars appears red due to the presence of iron oxide (rust) on its surface, which reflects sunlight in a reddish hue. 2. **How do sizes of Earth and Mars compare?**\ Mars is about half the diameter of Earth and has approximately...

**General Characteristics** 1. **Why is Mars red?**\ Mars appears red due to the presence of iron oxide (rust) on its surface, which reflects sunlight in a reddish hue. 2. **How do sizes of Earth and Mars compare?**\ Mars is about half the diameter of Earth and has approximately 1/10th the mass. 3. **How would you compare the size of Mars to Earth?**\ Mars is significantly smaller, with only about 15% of Earth\'s volume and 11% of its surface area. 4. **How does a Martian day compare to an Earth Day?**\ A Martian day, called a \"sol,\" is approximately 24 hours and 37 minutes, slightly longer than an Earth day. 5. **How does a Martian year compare to an Earth year?**\ A Martian year is 687 Earth days long, almost twice the length of an Earth year. 6. **Why is Mars so much colder than Earth?**\ Mars is colder because it is farther from the Sun and has a thin atmosphere, which cannot retain much heat. 7. **How are Mars and Earth similar? How are they different?** - **Similarities**: Both have polar ice caps, seasons, and similar day lengths. - **Differences**: Mars has a thinner atmosphere, colder temperatures, no liquid water on the surface, and is smaller in size. 8. **What are the white areas at Mars' poles?**\ These are polar ice caps made of water ice and carbon dioxide (dry ice). 9. **What features on Mars reminded early astronomers of Earth?**\ Early astronomers noted features resembling canals, polar ice caps, and seasonal changes, which they associated with Earth-like qualities. 10. **What does \"Earth and Mars at opposition\" mean?**\ This occurs when Mars is on the opposite side of Earth from the Sun, making it appear brightest and closest in the night sky. 11. **What two factors produce seasonal changes on Mars?** - Mars\' axial tilt (25.2°, similar to Earth\'s tilt). - Its elliptical orbit around the Sun. 12. **What two things occur on Mars as a result of seasonal changes?** - Growth and shrinking of polar ice caps. - Dust storms, sometimes planet-wide. 13. **What is the primary atmospheric gas in the Martian atmosphere?**\ Carbon dioxide (CO₂), making up about 95% of the atmosphere. 14. **How would you compare the atmospheric pressures on Earth and Mars?**\ Mars\' atmospheric pressure is less than 1% of Earth\'s, making it extremely thin. **Exploration** 15. **Why do scientists and others want to explore Mars?** - To study its potential for past or present life. - To understand its geology and climate. - To prepare for possible human colonization. **Geologic History** 16. **How do scientists determine the relative ages of different areas on Mars?**\ By counting the number and size of impact craters---older regions have more craters. 17. **What are the three main geological periods on Mars?** - **Noachian** (4.1--3.7 billion years ago): Heavy cratering and potential liquid water. - **Hesperian** (3.7--3 billion years ago): Volcanic activity and declining water. - **Amazonian** (3 billion years ago--present): Dry, cold conditions with minimal surface changes. 18. **Concerning Mars' moons: How many? Size compared to our moon? Size relative to Mars? Names?** - **Number**: 2 moons (Phobos and Deimos). - **Size compared to our Moon**: Much smaller; Phobos is about 22 km across, Deimos is 12 km across. - **Size relative to Mars**: Tiny, irregularly shaped objects. 19. **What is the Hemispheric Dichotomy on Mars?**\ A striking difference between the northern lowlands (smooth and flat) and southern highlands (heavily cratered and elevated). 20. **What is the main difference between the northern and southern hemispheres of Mars?** - Northern hemisphere: Lower, smoother, younger terrain. - Southern hemisphere: Higher, heavily cratered, older terrain. 21. **How was the Borealis Basin likely created?**\ Likely formed by a massive impact early in Mars\' history. 22. **What are some distinguishing characteristics of Mars' Noachian period?** - Heavy cratering. - Evidence of flowing water, such as valley networks. - Formation of the planet's oldest surfaces. 23. **What is the most likely explanation for the creation of river valleys during the Noachian Period?**\ Liquid water likely flowed on the surface due to a warmer, thicker atmosphere. 24. **Why was the loss of Mars' magnetic field significant?**\ Without a magnetic field, Mars\' atmosphere was stripped away by solar wind, leading to the planet\'s current thin atmosphere. 25. **What is the Tharsis Plateau?**\ A massive volcanic region that houses some of the largest volcanoes in the solar system, including Olympus Mons. 26. **Why is the Hesperian Period on Mars a period of transition?**\ During this time, Mars transitioned from a wet environment to the dry, cold planet we see today. Volcanic activity declined, and liquid water largely disappeared. **Maps and Surface Features** 27. **Why is the map of Mars colored as it is?**\ To indicate elevation and surface features---blue typically represents lower elevations, while red/orange represents higher ones. 28. **What number above is the location of Olympus Mons?**\ Olympus Mons would correspond to a number in a volcanic region (likely in red on the map). 29. **What numbers above are Noachian terrains?**\ Heavily cratered areas are Noachian terrains. 30. **What number above is a large impact basin?**\ The Hellas Basin is an example of a large impact basin, represented by a depression on the map. 31. **What number above is the Northern Lowlands?**\ The smooth, blue-colored area on the map represents the Northern Lowlands. 32. **What is the significance of the white wavy line on the map?**\ Likely represents the boundary between the northern lowlands and southern highlands (Hemispheric Dichotomy). 33. **What type of volcano is Olympus Mons?**\ A shield volcano, characterized by its broad, dome-shaped structure formed by lava flows. 34. **What surface features on Mars suggest that liquid water existed there?** - Valley networks. - Outflow channels. - Sediment deposits resembling river deltas. 35. **What is the significance of atmospheric pressure for liquid water?**\ Mars\' low atmospheric pressure prevents liquid water from existing on the surface today---it either freezes or evaporates. 36. **Why did liquid water disappear from Mars' surface long ago?** - Loss of magnetic field and atmosphere. - Cooling of the planet, leading to freezing temperatures. 37. **What is the main force of change on Mars during the Amazonian period?**\ Wind erosion and dust storms. 38. **What are present conditions like on Mars (Amazonian)?**\ Cold, dry, with a thin atmosphere and occasional dust storms. 39. **What surface features suggest that ice exists on Mars presently?** - Polar ice caps. - Subsurface ice detected by radar. - Frost deposits in shaded areas. 40. **How many Starbucks presently exist on Mars?**\ None! Mars is still waiting for its first coffee shop. Top of Form Bottom of Form