Cheapest way to travel for The primary way we come to discover their existence is when they cross the plane on which Earth orbits, about AU away from the Sun, and Earth passes through them fig. FIG How meteoroid streams may give rise to meteor showers and storms. The meteoroids in a meteoroid stream are crossing Earth’s orbit when Earth is present. This image is not to scale. Image credit Sirscha Nicholl, using an image of Earth at night from NASA Earth Observatory. Essentially, meteors are bright streaks in the night sky that occur when meteoroids crash into Earth’s upper atmosphere. The meteoroids begin to heat up when encountering resistance at ? km altitude. Cheapest way to travel 2016.