Israel\'s first astronaut, Air Force Col. Ilan Ramon, is still unsure if and when his scheduled NASA space-shuttle launch will take place. NASA announced on Friday that mysterious fuel-line fractures will keep four upcoming space shuttles grounded for at least two more months - although the tiny cracks are now considered less of a safety concern than before. Space Shuttle Program manager Ron Dittemore said that space experts are closing in on a plan that could enable a shuttle flight as early as September; decisions would still have to be made on which flight would take place. Col. Ramon is scheduled to take part in the STS-107 shuttle, a mission devoted to research, as Payload Specialist. STS-107 is to include over 80 experiments studying Earth and space science, advanced technology development, and astronaut health and safety.