(AP) -- Tests and testifying will take up what NASA hopes is the last day in orbit for the space shuttle Atlantis.
With a landing scheduled for Friday, astronauts on the shuttle on Thursday will be conducting routine tests on landing systems needed before they return to Earth.
But the weather on Friday in Florida does not appear too welcoming. If needed, Atlantis conserved some power to continue landing attempts through Monday, when it runs out of oxygen.
NASA will only try to land in Florida on Friday.
Also Thursday, astronauts were to testify briefly from orbit about NASA's budget before the Senate Commerce, Justice and Science Appropriations Subcommittee.
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