Dragon on its way to the international space station, Falcon 9 on its way to the landing pad. Image source: SpaceX.

Early Monday morning private U.S.-based rocket company, headed by Elon Musk, who is also the CEO of Tesla Motors, landed its fifth first-stage 165-foot tall Falcon 9 rocket in less than seven months. The successful landing follows a failed attempt in June, when "early liquid oxygen depletion caused [a Falcon 9 engine] shutdown just above the deck," Musk said on Twitter last month. By following up its failed landing attempt in June with a success, Monday's landed Falcon 9 gives the CEO's bold prediction earlier this year that SpaceX could achieve a 70% landing rate during 2016 more credibility than ever.

An improving track record

While SpaceX was making progress toward its 70% target earlier this year, its failed landing attempt in June made the company's target seem less certain, as SpaceX had only landed three of six attempts during the year. But despite the fiery ending to SpaceX's June landing attempt, Musk remained confident in the company's 2016 target rate for landings.

"As mentioned at the beginning of the year, I'm expecting ~70% success rate on landings for the year," Musk reaffirmed on Twitter after Falcon 9's rapid unscheduled disassembly, or RUD, on the barge in June. "2016 is the year of experimentation."

SpaceX's landing on Monday, which was its fifth overall and fourth this year, gets SpaceX closer to its target 70% landing rate. The ground landing occurred after the company launched Falcon 9 from Cape Canaveral Florida and deployed its Dragon cargo capsule into orbit. The Dragon cargo is headed to the International Space Station, set to deliver about 5,000 pounds of cargo.

Falcon 9 landing. Image source: SpaceX.

With its July 18 landing now behind it, SpaceX has landed four of seven rockets this year, or about 57% of its total attempts. This is a huge improvement from the company's landing track record in 2015. Last year, SpaceX failed three of its experimental landings before it finally succeeded in December.

Two of SpaceX's landings -- its first and its most recent -- occurred on ground. The other three happened on a barge at sea. SpaceX considers ground landings much easier than its sea attempts. Ground landings, however, are not always possible; launches requiring a higher velocity due to heavier payloads or higher orbit destinations leave Falcon 9 with less fuel to make it all the way back to land.

Important progress

SpaceX's growing number of both sea and land rocket recoveries comes at a critical time for the company. Two milestones on the horizon will make rocket recoveries more important than ever for SpaceX.

First, SpaceX plans to start actually reusing rockets soon. Currently, the company is aiming for its first reflight in September or October. Longer-term, SpaceX hopes reusing rockets will dramatically reduce the cost of space launches.

Rendering of Falcon Heavy. Image source: SpaceX.

Second, the company is prepping its Falcon Heavy for its first launch later this year. Falcon Heavy, which will be the world's most powerful operational rocket by a factor of two when it launches, is basically made up of three Falcon 9 rockets strapped together. Each of the three rockets making up Falcon Heavy will attempt to land on its own, making landing successes even more critical.

As SpaceX sets its sights on finally reusing rockets and its first launch of Falcon Heavy, Elon Musk has an even more ambitious goal for its landing success rate next year. In 2017, SpaceX hopes to land nine out of every 10 rockets.