Sunita replaced German astronaut Thomas Reiter on the ISS, who will return to earth after a five-month sojourn in space.
The airlock at the lower pressure protects against decompression sickness, commonly called "the bends," as the two go to the even lower pressure of spacesuits on Tuesday.
Despite doubts about the take-off due to poor weather forecast and a two-hour delay before tanking operations, Discovery and its crew of seven lifted off from the Kennedy Space Center in Houston at 7:17 am IST.
England, Canada and Israel remained the nations generating the warmest feelings among Americans. Americans' warmth toward China, India and Israel grew the most.
