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, the largest known dwarf planet, was first detected in data collected in October of 2003. It was not identified until January of 2005. Mike Brown and his team of astronomers discovered what was considered to be the 10th planet while doing observations at the Palomar Observatory in California.t 2400 kilometers in diameter, Eris is slightly larger than Pluto. Its discovery was one of the reasons the International Astronomical Union felt it was necessary to definitely define what should be considered a planet. Eris does not clear out its orbit, so it did not meet one of the requirements.