Iconic Planet-Hunting Kepler Telescope Wakes Up, Phones Home (space.com)

Kepler, which has discovered about 70 percent of the 3,800 known exoplanets to date, woke up from a four-week hibernation yesterday and has begun beaming data home, just as planned, NASA officials announced today. From a report: Kepler had been sleeping in an attempt to save thruster fuel, which is running very low. Mission team members wanted to make sure the spacecraft had enough propellant left to orient its antenna toward Earth for yesterday's data dump. Far-flung NASA spacecraft send information back to mission controllers via the agency's Deep Space Network (DSN), a system of radio dishes around the globe. The sun-orbiting Kepler's latest allotted DSN window opened yesterday, agency officials have said.

Comments

Non-propellent based space travel

[jellomizer]

It is too bad that for space travel there isn't much alternatives to propellant to alter and correct course.
The mars rovers for the most part have well exceeded their design life cycle mostly due to the fact that it is solar powered and uses electric motors for its transpiration. If needed an expendable fuel it would had only lasted its prescribed life cycle.
However good old physics shows that an electric motor may be able to spin and rotate a space craft there isn't much it can do for course, and prevent it from leaving an orbit.