After one of the Russian rockets it plans to use to ferry astronauts and supplies to the International Space Station crashed last week, NASA said on Monday it may evacuate the station and let it orbit unmanned for a while. The NASA announcement follows one from the Russian space agency, which said it would postpone a manned mission to the station that had been scheduled for Sept. 22. That mission has been pushed back to late October, and in the meantime the Russian agency, Roscosmos, has scheduled two unmanned missions. The Soyuz rockets were supposed to take over for space shuttles in bringing U.S. astronauts and supplies to the station. But last week's crash has called that plan into question. "If Russian Soyuz rockets remain grounded beyond mid-November, there will be no way to launch new crews before the current residents are supposed to leave," the Associated Press reported on Monday. "Currently, six astronauts reside on the space station," writes Space.com's Mike Wall. "But three of them are due to return to Earth next month, and the rest are scheduled to come back in mid-November. If the rocket anomaly isn't identified and fixed soon, a fresh crew won't be able to get to the station before the last three astronauts depart."