After a lengthy hiatus from spaceflight, SpaceX will launch its next Falcon 9 rocket again on December 19th. A recent tweet by ORBCOMM's CEO, Marc Eisenberg, on Dec. 9, 2015, stated that the spacecraft were set and ready to be launched on the first flight of a Falcon 9 since one of the rockets was lost earlier this year. Elon Musk, SpaceX CEO, also revealed the launch date on Twitter early this morning, noting that the launch would be "about three days" after December 16th.

SpaceX's rockets have been grounded since June, after one of its Falcon 9 rockets exploded while carrying supplies to the International Space Station. The flight lasted some two minutes and 19 seconds - before the rocket's second stage exploded - resulting in the loss of the rocket, the Dragon spacecraft integrated to the top of the F9, and the 4,000 lbs (1,800 kg) of supplies and experiments bound for the International Space Station.

According to The Verge, the failure was caused by a faulty steel strut in the rocket's fuel tank. After the accident, the company launched a detailed investigation into the issue, and Musk noted that moving forward, all the struts in the fuel tanks would be individually tested before each flight.

The upcoming launch will test out a new version of the Falcon 9 that will make it easier for the company to recover the rocket after take-off. For the past year, SpaceX has been trying to gently land its Falcon 9 rocket on a platform at sea post-launch. Normally, orbital rockets are either destroyed or lost after taking off, so recovering the rocket intact would be a technological first. This time around, SpaceX will try another type of first, too. It will attempt to land the rocket back on solid ground at Cape Canaveral, Florida rather than its autonomous drone ship in the ocean.

Spaceflight Insider says that, as has been the case with 18 of the 19 launches of the Falcon 9, the launch of ORBCOMM OG2 will get its start from the Cape's Space Launch Complex 40 located in Florida. The F9 will then attempt to land near the launch site after it has successfully completed its part in delivering the Orbcomm satellites to orbit.

The Orbcomm OG2 satellites are planned to replace the current first generation versions of these spacecraft currently on-orbit. Initially, the Orbcomm OG2 constellation was set for launch on SpaceX's Falcon 1e booster. With that rocket now retired, the spacecraft will ride the far more powerful Falcon 9 v1.2 variant of the F9.

A lot of eyes will be on this launch, especially those at NASA. SpaceX is one of two companies that will be transporting NASA astronauts to and from the International Space Station starting in 2017.  SpaceX is also in the running for NASA's second round of Commercial Resupply contracts, which task private companies with periodically resupplying the ISS. Those contracts will be awarded in January 2016, and this upcoming launch will likely factor into NASA's decision.