New Horizons expanded the boundaries of the Kuiper Belt, discovered “snowmen” and other unusual objects
The Kuiper Belt may extend billions of miles further than anyone imagined. NASA’s New Horizons spacecraft encountered Pluto in 2015, then spent an extended period in the deepest layers of the Kuiper Belt and encountered a cosmic dust storm, suggesting that the outer reaches of the Solar System may be even further away than we imagine.
Planet or not a planet? Pluto’s status raises serious questions about how to define any object in the solar system
The current debate over Pluto highlights the difficulties in defining the concept of “planet.” The IAU defines a planet as a celestial body orbiting the Sun, having a nearly spherical shape, and having largely cleared its orbital environment of space debris. But even this set of criteria is not universally accepted.
Modern questions about the solar system: its speed, boundaries, hidden objects in the outer part
The solar system may be moving through space three times faster than expected. The location of the outer edge of the solar system is also a subject of debate among astronomers. Here’s a simple guide to the sizes and locations of the planets in our solar system.
Candidates for Planet Nine in the depths of our solar system
The predicted position of Planet Nine is intended to explain the irregular orbits of some Kuiper Belt objects in the outer solar system. However, some researchers are unconvinced that these orbits are caused by an undiscovered planet, and the scientific community as a whole still awaits direct observational evidence of Planet Nine’s existence. If Planet Nine does exist, researchers predict it to be much larger than Earth and to orbit in an unusual orbit billions of miles from Neptune, the eighth and currently last planet in our solar system. Planet Nine’s proposed orbit is so far from the Sun that it would be difficult for Earth-based scientists to detect it, making it difficult to prove or disprove its existence.
Recent studies of Pluto’s moon Charon have revealed that it contains water ice, ammonia and organic compounds, carbon dioxide, and hydrogen peroxide
Charon is a medium-sized body, approximately 750 miles (1,207 kilometers) wide, located in the Kuiper Belt—a ring of icy debris, comets, and dwarf planets, also called trans-Neptunian objects (TNOs), at the edge of the solar system. Unlike many larger Kuiper Belt objects, Charon’s surface is not covered in volatile ices like methane, allowing scientists to gain valuable insight into the influence of sunlight on cratering these distant bodies. Furthermore, Charon is the only medium-sized TNO for which geological mapping is available. This was made possible thanks to data collected by NASA’s New Horizons spacecraft, which visited the Pluto system about a decade ago.