ES+2232-Lab+02-Planetary+Atmospheres-2023_v2

ES 2232G: Exploring the Planets: Sun, Earth, Planets Laboratory 02 – Planetary Atmospheres (Materials reproduced from the Astronomy Education at the University of Nebraska-Lincoln Web Site (http://astro.unl.edu). INTRODUCTION This lab explores some of the elements that go into the retention or loss of an atmosphere by a planet. Open a web browser and point to: http://astro.unl.edu/naap/atmosphere/atmosphere.html . Work through the background sections on Escape Velocity, Projectile Simulation, and Speed Distribution. Then complete the following questions related to the background information. Question 1: Imagine that asteroid A that has an escape velocity of 50 m/s. If asteroid B has twice the mass and twice the radius, it would have an escape velocity ______C________ the escape velocity of asteroid A. (1 mark) a) 4 times b) Twice c) the same as d) half e) one-fourth Question 2: Complete the table below by using the Projectile Simulator to determine the escape velocities for the following objects. Since the masses and radii are given in terms of the Earth’s, you can easily check your values by using the mathematical formula for escape velocity. (5 marks) Object Mass (Mearth) Radius (Rearth) v esc (km/s) v esc (km/s) calculation (optional) Mercury 0.055 0.38 4.3 km/s     0.055 11.2 4.3 0.38 km km s s        Uranus 15 4.0 21.7 km/s √15/4 (11.2km/s) = 21.7 km/s Io 0.015 0.30 2.5 km/s √0.015/0.3 (11.2 km/s) = 2.5 km/s Vesta 0.00005 0.083 0.3 km/s √0.00005/0.083 (11.2 km/s) = 0.3 km/s Krypton 100 10 35.4 km/s √100/10 (11.2 km/s) = 35.4 km/s Earth Sciences 2232G: Lab 02 1

Question 3: Experiment with the Maxwell Distribution Simulator. Then a) draw a sketch of a typical gas curve below, b) label both the x-axis and y-axis appropriately, c) draw in the estimated locations of the most probable velocity v mp and average velocity v avg , and d) shade in the region corresponding to the fastest moving 3% of the gas particles. (3 marks) Earth Sciences 2232G: Lab 02 2