Exclude words from your search Put - in front of a word you want to leave out. For example, jaguar speed -car
Search for an exact match Put a word or phrase inside quotes. For example, "tallest building".
Search for wildcards or unknown words Put a * in your word or phrase where you want to leave a placeholder. For example, "largest * in the world".
Search within a range of numbers Put .. between two numbers. For example, camera $50..$100.
Combine searches Put "OR" between each search query. For example, marathon OR race.
An artist's vision of an exotic binary system illustrates how matter is drawn from the roughly solar-mass star into the black hole. (Image courtesy of M. Weiss (CXC), NASA on the Astronomy Picture of the Day Web site.)