| 1 | Those atoms could simply drift from the planet into space. | |
| 2 | It gives way to the whitish stratosphere and then into the mesosphere. | |
| 3 | Hydrodynamic escape may have stripped Titan of much of its air, too. | |
| 4 | Atmospheres rich with hydrogen are the most vulnerable to hydrodynamic escape. | |
| 5 | Recognizing the importance of atmospheric escape changes our perspective on the solar system. |