BEGINNING OF SPRING. REPORTING IN GARFIELD PARK, ANDREW RAMOS, CBS NEWS CHICAGO. >>> FOR THE FIRST TIME IN HISTORY, TWO PRIVATE ASTRONAUTS COMPLETED A SPACEWALK. BILLIONAIRE JAROD ISAACMAN FLOATED OUTSIDE OF THE SPACEX CAPSULE THIS MORNING, MORE THAN 400 MILES ABOVE EARTH. A SHORT TIME LATER, MISSION SPECIALIST SARAH GILLIS FOLLOWED HIM. THEY WERE TESTING NEW