This summer, NASA launched a space mission to hunt for Earth-like worlds that may harbor alien life.

Scientists believe that the three and a half years voyage of the Kepler telescope, considered one of the agencys most exciting unmanned spacecraft, will help answer the centuries-old question: “Are we alone in the universe?”

They say the search could yield 50 or more potentially habitable planets beyond our solar system.

“If we find that many, it will certainly mean life may well be common throughout our galaxy,” said Bill Borucki, the projects principal investigator at NASAs Ames Research Centre in California.

“On the other hand, if we dont find any, that is still a profound discovery. It will mean that Earth must be very rare—we may be the only life in our universe. Itll mean there will be no Star Trek.”

The Kepler will be able to search a region of space 3,000 light years across. It will not find E.T., but its finding E.T.s home.

Question: What does the underlined sentence “If we find that many” mean?

Answer: