Physics Today Online: In a lecture celebrating NASA's 50th anniversary at George Washington University yesterday, theoretical astrophysicist Stephen Hawking and his daughter Lucy Hawking, a journalist and book author, argued that an active human spaceflight program is one of the few opportunities for governments to attract students into the sciences.

“The low esteem in which science and scientists are held by the public is a significant problem,” said Stephen Hawking. “Never before has science and technology played such a big role in our lives, and yet the children of today are not interested in science.”

Lucy Hawking followed up on her father’s observation by providing examples of the public's poor grasp of scientific knowledge. She said that “72% of UK students couldn’t identify the Moon from a picture. And only 4% of US adults could name a living scientist, although 96% of those surveyed said it was important for the US to invest in science education.” A large number of scientists were inspired to go into science because of an interest in astronomy; “Kids never tire of hearing about human spaceflight,” she added.

Stephen Hawking pointed out that NASA’s budget forms a small part of the US GNP (gross national product) and that increasing investment in the international space exploration budget by a factor of 20 would still be a small amount (0.25%) of the world’s financial resources. Humanity can afford to battle earthly problems like climate change and still have plenty of resources left over for human spaceflight exploration, he said.

"A goal of a base on the Moon by 2020 and of a manned landing on Mars by 2025 would reignite the space program and give it a sense of purpose in the same way that President Kennedy's Moon target did in the 1960s," Stephen Hawking said. Humans should return to the Moon because it is "close by and relatively easy to reach," and, assuming there are water deposits at the lunar poles, it could be a base for travel to the rest of the solar system.

Mars would be "the obvious next target", with its abundant supplies of frozen water and minerals brought close to the surface through volcanic eruptions. "There is also tantalizing possibility that life may have been present there in the past." Saturn’s moon Titan sounds like an intriguing place to visit, he said, although it's cold: “I wouldn’t want to live next to a lake of liquid methane.”

Hawking dismissed robotic missions as a way to inspire the next generation of children because although "robotic missions are much cheaper and may provide more scientific information, they don't catch the public imagination in the same way.”

Although attracting children to science education is one of Hawking’s reasons for supporting NASA’s plans to return to the Moon, he said that human space exploration should be a long-term (200-500 years) strategy for the species, including attempting interstellar travel.

“If only 1% of the 1000 or so stars within 30 light-years of Earth has an Earth-size planet at the right distance from its star for liquid water to exist, that would make for 10 such planets in our solar system's neighborhood,” he said. “If we want the human species to survive another million years, then we need to ‘boldly go where no one has gone before.’”

Hawking also theorized about the existence of life elsewhere in the universe, stating that he believed primitive life is very common and intelligent life is fairly rare. He then joked, "some would say it has yet to occur on Earth."