US probing SpaceX's Starship test that exploded in Dec

According to the FAA, SpaceX has violated the terms of its Federal Aviation Administration test license, reports The Verge. 

"The FAA will continue to work with SpaceX to evaluate additional information provided by the company as part of its application to modify its launch license," FAA spokesperson Steve Kulm said on Friday. 

"We will approve the modification only after we are satisfied that SpaceX has taken the necessary steps to comply with regulatory requirements." 

A prototype of Elon Musk's aerospace company SpaceX's next-generation heavy-lift rocket Starship exploded on landing after a high-altitude test flight in Texas. 

The launch and ascent of Starship serial number 8 (SN8) were successful, but as the engines appeared to reignite for landing, the vehicle flipped back to vertical and then slammed into the ground. 

"Low pressure in the fuel header tank during the landing burn led to high touchdown velocity," SpaceX said on its website. 

Starship is SpaceX's fully reusable transportation system designed to carry both crew and cargo to the Earth's orbit, the Moon, Mars, and beyond. 

The company is working towards launch of an uncrewed Mars flight in about two years.