Moonshots Beyond the Cloud

Celestia for Android , my favorite universe simulation app, supports downloading add-ons from the project’s repository . This extensive archive hosts digital models of asteroids, deep-sky objects, exoplanets, spacecrafts, and more. The add-ons of spacecrafts are interesting as they let you examine the environment and context of historical space exploration missions , such as the views the vehicles had of their target bodies. But historical add-ons pose a potential pitfall. The Mariner 4 add-on in Celestia for Android on my Pixel 4 XL phone. The simulation date and time are set to a moment a few hours prior to the closest approach to Mars. Consider, for example, the add-on of Mariner 4 , the first human-made vehicle to fly by the planet Mars. If you download the add-on and go to it with the Celestia browser (menu > Browser > Spacecraft > Mariner 4 > GO ), the app will navigate to the 3D model of the spacecraft and make it fill up most of the field of view. But where is Mars?...