If you want to visit (and not live in) the United States you must first obtain a visitor visa. Travelers from certain countries may be exempt. If you want to travel to the United States for reasons other than business or pleasure, such as study or work, you must apply for a visa in the appropriate category. DHS provides a full range of online resources to help you plan your trip, manage your arrival and if needed extend your stay.
Some astronomers called Eris our Solar System's tenth planet when it was first discovered. After a lot of discussion, astronomers decided to make up a new category for objects like Eris. That is where the idea of dwarf planets came from.
Eris is green which is unlike any other planet an very unusual. Eris is also the largest known dwarf planet in the Solar System. It is approximately 2 500 kilometers in diameter and 27% more massive than Pluto. Since it is so far away it take Eris about 558 years to orbit around to Sun. Eris was first spotted in 2003 by a Palomar Observatory-based team led by Mike Brown.