![planetbase rotate building planetbase rotate building](https://xblafans.com/wp-content/uploads/2017/08/Plaetbase_Ice-Planet-660x371.jpg)
Similarly, sunlight can also alter the rotation rate of small asteroids.
![planetbase rotate building planetbase rotate building](https://cdn.akamai.steamstatic.com/steamcommunity/public/images/clans/37623196/0a197b873469a4185c422fc65042e87f81bdfd1d.png)
Over millions of years, this force, called the Yarkovsky effect, can noticeably alter the trajectory of smaller asteroids (those less than 25 miles, or about 40 kilometers, in diameter). When the heat escapes, it creates an infinitesimal amount of thrust, pushing the asteroid ever so slightly off its course. At any given moment, the Sun-facing side of an asteroid absorbs sunlight while the dark side sheds energy as heat. That's right, sunlight can move asteroids! Like Earth and many other objects in space, asteroids rotate. The Trojans lead and follow Jupiter in its orbit by 60 at Lagrange points L4 and L5. These are locations where the gravitational forces of two massive objects - in this case the Sun and Jupiter - are balanced in such a way that smaller objects like asteroids or satellites stay put relative to the larger bodies. They are clustered at two Lagrange points. In the case of the Trojan asteroids that Lucy will visit, their very location in space is dictated in part by the Sun's gravity. The Sun makes up 99.8% of the solar system's mass and exerts a strong gravitational force as a result.
![planetbase rotate building planetbase rotate building](https://i.loli.net/2018/05/10/5af345b8a8cc8.png)
Here are a few of the ways the Sun influences asteroids like the Trojans in our solar system. Directly and indirectly, the Sun affects many aspects of existence within this pocket of the universe. Like all the planets, asteroids exist in the heliosphere, the vast bubble of space defined by the reaches of our Sun's wind. It will take the spacecraft about three and a half years to reach its first destination. Over the next 12 years, NASA's Lucy mission will visit eight asteroids - including seven Trojans - to help answer big questions about planet formation and the origins of our solar system. The Trojans are thought to be left over from the objects that eventually formed our planets, and studying them might offer clues about how the solar system came to be. Jupiter's Trojan asteroids, which orbit the Sun on the same path as the gas giant, are no exception. Asteroids embody the story of our solar system's beginning.