Elon Musk: Hover rocket? Check. Hover ship? Check. Let's DO THIS

Elon Musk's SpaceX will attempt – for the second time – to land one of its reusable Falcon 9 rockets on a floating hover-ship out at sea, just a month after its last effort ended with a catastrophic explosion.

Blast off of the rocket is expected to happen later today, Sunday, when it is scheduled to launch a space weather observatory into orbit. A lower stage of the Falcon 9 will try to touch down vertically on the floating pad, allowing SpaceX to reuse it for other missions.

That particular launch was slated for late last year, but NASA was forced to push back its DISCOVR (the Deep Space Climate Observatory) mission until now, after the US space agency said it needed more time to load supplies following the Orbital Sciences' Antares rocket explosion.

NASA added in December that an anomaly during a test firing of the Falcon 9 also delayed lift off.

The US National Oceanic and Atmospheric Administration has teamed up with NASA on the DSCOVR project to provide real-time solar wind monitoring – a key input into weather forecasting.

The satellite will also be used to forecast space weather, to help us have a better understanding of likely disruption to Earth-based electronics and electricity grids caused by solar events.

"One of our main questions about the solar wind is based on the fact that it cools down as it moves toward Earth but not as fast as we'd expect," said NASA’s DSCOVR project boffin Adam Szabo.

"There must be some heating mechanism that slows down the cooling. The solar wind instruments on DSCOVR will help us determine what's providing that extra heat." ®

Updated to add: Launch scrubbed

Just minutes before take-off, tracking problems caused the launch to be scrubbed for at least 24 hours. A first stage transmitter and a range radar were the items blamed for the delay. The launch - and SpaceX's possible rendezvous with destiny - is currently set for 6:07 pm Monday (US Eastern time).