SpaceX, the Hawthorne, California-based commercial space transport company that flies contract resupply missions to the orbiting International Space Station, continues its march towards launching ---and returning to earth --- a rocket with landing legs.

The company's visionary founder, Elon Musk, tweeted a picture over the weekend of SpaceX workers connecting landing gear to the Falcon 9 rocket to be used in March to lift a Dragon supply craft into low-earth orbit, where it will dock with the space station.

The company's ultimate plan is to eventually be able to reuse Falcon 9s for its missions.

Specifically developed for the National Aeronautics and Space Administration, the $278-million Falcon 9 launch vehicle uses nine Merlin engines and aluminum-lithium alloy tanks that contain liquid oxygen and rocket-grade kerosene propellant.

According to SpaceX, the rocket produces an initial thrust greater than that of five Boeing 747s at full power --- which then increases with altitude.

Currently, when a Falcon 9 is done pushing the Dragon capsule to orbit, it falls back to Earth and crash-lands in the Pacific Ocean, where it ends up destroyed.

SpaceX previously attempted to restart the rocket in hopes of softening its return impact and then salvaging it. After that idea proved unworkable, company designers have opted to mount landing legs, made of state-of-the-art carbon fiber with aluminum honeycomb, to lessen the water landing.

The four legs will be installed symmetrically around the base of the Falcon 9 and will be stowed along the side of the vehicle during liftoff, then later extended outward in preparation for landing.

Musk has said in the past he'd like to guide the Falcon 9 earthward for a controlled landing, like SpaceX's Grasshopper rocket, which has successfully completed a handful of powered jumps and then safely returned land, setting down on its own set of landing legs.

"However, F9 will continue to land in the ocean until we prove precision control from hypersonic thru subsonic regimes," Musk wrote on the SpaceX Twitter account.

At this point, indicated SpaceX spokeswoman Emily Shanklin in a story by Reuters, the odds of a successful Falcon 9 are less than 40 percent.

Nonetheless, SpaceX will be trying out the new legs March 16 when the Dragon ascends to space on its third of resupply mission.