Earth and the Solar System Worksheet_answers

Geology 4L Planet Earth Lab Name: Lab 2: The Solar System Worksheet Part I: A Walking Tour of the Solar System In the first part of this lab, your instructor will guide you through some physical features of the solar system. The solar system is a VERY big place and the huge distances involved are difficult to visualize. A scale model can help but because the distances between planets are so huge compared to the size of the planets, this can be tricky. In this lab, you will experience a “Thousand Yard Model” of the solar system in which the distance from the Sun to Pluto is 1,000 yards (3,000 feet). The space required for this scale model will require that we go outside. Questions to answer before the walk In our Thousand Yard scale model, the Sun is about 8 inches in diameter . The images below represent the sizes of the nine planets (we’ll let Pluto be a member of the solar system for now). In the space to the right of each picture below write the name of the planet or planets that would be about this size if the Sun were 8 inches across. Make sure to account for all 9 planets (assuming Pluto had not been kicked out of the solar system). Questions to answer after the walk 1. How do the distances between the planets closest to the Sun compare to inter-planet distances in the outer solar system? The distances between the planets closest to the Sun are smaller compared to the distances in the outer solar system. 2. How do the sizes of the inner planets compare to the sizes of planets in the outer solar system? The sizes of the planets in the inner solar system are smaller than the sizes of the planets in the outer solar system Relative Size Planet(s) Relative Size Planet(s) Jupiter Saturn Earth Venus Mars Mercury Uranus Neptune Pinhead, or smaller Pluto

Part 2: Planet Patterns (Modified after: http://www.noao.edu/education/peppercorn/pcmain.html) In this portion of the lab, you will consider planetary data and construct graphs that enable you to make comparisons and look for patterns. 1. Using the planetary data provided in Table 1, graph the data onto GRAPH 1 on the next page. LABEL each planet on the graph. TABLE 1: PLANETARY DATA Property Mercury Venus Earth Mars Jupiter Saturn Uranu s Neptun e Pluto Mass (10 24 kg) 0.3302 4.869 5.975 0.641 9 1,898.6 5 568.46 86.83 102.43 0.0125 Eq. Radius (km) 2,439 6,052 6,378 3,393 71,492 60,268 25,559 24,766 1,137 Mean Density (kg/m 3 ) 5,427 5,204 5,520 3,933 1,326 687 1,318 1,638 2,050 Orbital Distance (10 6 km) 57.9 108.2 149.6 227.9 778.3 1,427. 0 2,869.6 4496.6 4,913. 5 Orbital period (days) 87.969 224.7 365.2 5 686.9 8 4330.6 10,747 30,588 59,800 90,591 GRAPH 1: DENSITY VS. DISTANCE Mean density (kg/m 3 ) 6000 5500 5000 4500 4000 3500 3000 2500 2000 1500 1000 500 0 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0 4 0 0 0 4 5 0 0 5 0 0 0 5 5 0 0 6 0 0 0 Orbital distance (millions of km) 2. What is the relationship between a planet’s density and its distance from the Sun? The more dense a planet is the closer it s to the sun Mercury, Venus, Earth Mars pluto Jupiter uranus neptune saturn

d. Referring to Table 1 (from question 1) and Table 3 below: Material Density Air 1.2 kg/m 3 Water or Ice 1000 kg/m 3 Typical Rocks 3000 kg/m 3 Metal at High Pressure 10,000 kg/m 3 Table 3 1. Which two materials do you think are most abundant in the terrestrial planets? Air_and water or ice 1. Explain your reasoning Terrestrial planets are low density 2. Which planet(s) would float in water? Jupiter and Saturn 6. Orbital period GRAPH 2: ORBITAL DISTANCE VS ORBITAL PERIOD a. Referring to Graph 3, how would you describe the relationship between a planet’s orbital period and its distance from the Sun? b. The orbital period of the Earth is about 365 days. What is this called? A calendar year 6. Planetary Atmospheres (See Table 4) a. Which two planets have similar atmospheric compositions ?

venus and mars What makes their two atmospheres very different? Surface temperature and atmospheric pressure Planet or Moon Gases (% by volume) Mean Distance From Sun (millions of km) Surface Temperature (range) Surface Atmospheric Pressure (bars) N 2 O 2 CO 2 Mercury 0 trace 0 58 - 173 to 427C 10 -15 Venus 3.5 <0.0 1 96.5 108 475C (small range) 92 Earth 78.0 1 20.95 0.03 150 -40 to 75C 1.014 Earth’s Moon 0 0 0 Similar to Earth -173 to 130C Essentially 0 Mars 2.7 1.3 95.3 2 228 -120 to 25C 0.008 Table 4 b. Which gas (other than nitrogen) is abundant in Earth’s atmosphere, but nearly absent in the atmospheres Venus and Mars? Oxygen c. What explains its presence on Earth? (Hint: What does Earth have that Venus and Mars both lack?) Moderate temperature d. Note that even though Mercury is closer to the Sun, Venus is somewhat hotter. Why? (Hint: think atmospheres) Venus has a dense atmosphere; Mercury has almost no atmosphere

the horizontal line and one is on the bottom. This is useful to keep in mind if you aren’t sure which number should go where. In this case, inches will go on the bottom so that inches cancel out. We are converting to feet, so the only unit that will not cancel will be feet. You then multiply across. So, 24 x 1 =24 (If there was a second number below you bottom line, you would multiply across there too.) Then divide by the numbers that are below the horizontal line. So, 24 / 12 = 2 24 inches = 2 feet. You probably didn’t need dimensional analysis to figure that out, but this method becomes extremely useful when you need to use a few conversion factors. Consider the following example: Example 2: You want to convert 24 kilometers to feet. You don’t have a direct conversion between the 2 units. However, you do know the number of miles in 1 kilometer and the number of feet in 1 mile. Conversion factors: 1 km = 0.62 miles; 1 mile = 5280 ft. Try first… then read on if you get stuck: You have the number you are starting with (24 km) and 2 conversion factors, so you need 3 columns in your chart. The starting number goes on the top of the 1 st column (again, it’s implied that it is over 1). Your first conversion is between km and miles. Because you do not want the units km to be in the answer at the end of your conversion, you know that it has to cancel out, so you put km on the bottom, miles on top. Similar reasoning for the next conversion, miles cancels with miles and the only unit left is ft, which is the unit we are looking for. Then you just multiply by the numbers on top (so 24 x .62 x 5280 = 78,566.4), multiply the numbers on the bottom (1 x 1= 1). The last step is to divide top by bottom (78,566.4/ 1= 78,566.4ft) 24 km 0.62 mi 5280 ft = 78,566.4 ft 1 km 1 mi Your turn. Complete the following conversions using dimensional analysis. You will need to set up your own tables and show your work. 3. Convert 543 miles to kilometers 543/0.62 miles/km = 875.8 4. Convert 26.1 miles to meters . (216.1/0.62miles/km) = 42.096km = 42,096 meters (divide by 1000) 5. Convert 1000 inches to miles. 1000/12inches/ft = 83.33 feet. 5280ft in every mile > 5280/83.33 = 0.016 miles

6. Convert 150 days to seconds. (I am guessing you know the conversion factors between these: 1 day = 24 hrs; 1 hr = 60 minutes; 1 minute = 60 seconds.) 150 days = (150*24hrs/day) =3600 hours, (3600*60 minutes/hr)=216,000 minutes (216minutes * 60seconds/minute) =12,960,000 seconds 7. Sailors used to measure the depth of water using a unit of measurement known as a fathom . If they recorded a depth of water as being 5 fathoms , how deep was the water in meters? 1 fathom = 1.8 meters 5 fathoms = 5* 1.8 meters = 9 meters 8. The world’s biggest horse on record was named Sampson. He was 21.5 hands tall at the withers (base of the neck). How tall was Sampson in centimeters ? 1 hand = 4 in. 1 inch = 2.54 cm. 21.5 hands = 86 inches (multiply by 4) 86 inches = 218.44 cm ( multiply by 2.54) 9. Sampson weighed 3306.9 pounds. What was his weight in kilograms? 1 lb = 0.454 kg. 3306.9 x 0.454kg/pound = 1501kg 10. The F/A-18 Hornet has a top speed of Mach 1.8, which is equal to 1190 miles per hour. What is this speed in meters per second? 1190 miles/hr = 71,400 miles/minute (60 minutes in every hour) 4,284,000 miles/ second (60 seconds in every minute) 11. Convert Usain Bolt’s world record time in the 100 meter dash of 9.69 seconds to miles per hour. 1 mile = 1609.34 meters. 100 meters =0.06 miles (100/1609.24) 9.69seconds =0.1615 minutes (divide by 60 to get minutes) = 0.0027 hour (divide by 60 to get hours) So 0.06miles per 0.0027hour 12. How old are you in seconds? 19 years = 19*365 days in a year = 6935 days 6935 * 24 hours in a day = 166,440 hours 166440* 60 minutes in an hour = 9,986,400 minutes 9,986,400 minutes * 60 seconds in a minute = 599,184,000 seconds