Forget about spending much time on the moon. President Bush’s $16.2 billion NASA budget proposal envisions annual lunar missions, by humans and robots, as mere steppingstones to exploring Mars and beyond. “This is not about sending humans back to the moon,” NASA Comptroller Steve Isakowitz said, showing a computer-aided presentation with “Humans to the Moon” in a circle with a red slanted line through it. “The reason we’re going to the moon is because we don’t know today how to go to Mars,” he said. “We’re going to be using the moon first and foremost as a test bed to prepare the way for things we know humans could do of great value on Mars.”