His predictions included that planets had been explored but not colonized , and although rockets had become more powerful they had not replaced aircraft and ramjet vehicles .
In October 1967 , Singer wrote an article for The Washington Post from the perspective of 2007 .
Singer 's predictions included that planets had been explored but not colonized , and although rockets had become more powerful they had not replaced aircraft and ramjet vehicles .
In October 1967 , Singer wrote an article for The Washington Post from the perspective of 2007 .