Asteroids are small, rocky bodies that orbit the Sun. They are typically found in the asteroid belt between Mars and Jupiter. However, some asteroids have orbits that bring them closer to Earth. The largest known NEO is Ceres, which has a diameter of about 950 kilometers.
Comets are balls of ice and dust that orbit the Sun. When a comet approaches the Sun, its icy surface begins to melt and vaporize, creating a tail of gas and dust. Some comets have orbits that bring them close to Earth, and these comets can sometimes be visible from Earth with the naked eye. The most famous comet is Halley's Comet, which is visible from Earth every 75-76 years.
The threat from NEOs
NEOs pose a threat to Earth because they could potentially impact the planet. If a large NEO were to impact Earth, it could cause widespread damage. For example, an impact by an object about the size of the asteroid that killed the dinosaurs 66 million years ago could cause a global extinction event.
NASA's NEO program
NASA has a program in place to monitor NEOs and assess the potential threat they pose to Earth. The program includes a number of telescopes that are used to track NEOs and calculate their orbits. NASA also has a spacecraft called the Near Earth Object Surveyor (NEOSM) that is scheduled to launch in 2025. The NEOSM will be used to study NEOs and assess the threat they pose to Earth.
The future of NEO studies
NEO studies are becoming increasingly important as more and more NEOs are discovered. It is essential that we understand the threat from NEOs and that we develop strategies to mitigate that threat. By continuing to study NEOs, we can help to protect Earth from the potential impacts of these celestial bodies.
