As we approach the end of the 2010s, it's been fun to contemplate the coolest, most daring, and most significant feats of spaceflight during the last decade. Such an exercise leads inexorably to a simple conclusion—humans from around the world have done a lot of amazing things in space over the last 10 years.

For simplicity's sake, I had originally hoped to write about the five most important missions. But soon, I realized that this was far too limiting. Truthfully, even picking 10 of the biggest and best accomplishments during the last decade has proven incredibly challenging. We've had to leave out some really awesome things on this list, not to mention ultimately cheating (as this list goes to 11). It was so hard. If you read through the "honorable mentions" at the end of this list, there are literally dozens of incredible space feats. It makes me feel better about our species.

This is a subjective list, of course. I asked my followers on Twitter for suggestions on the "coolest" or "most exciting" or "best" space missions this decade and got 175 replies. I spoke with several NASA and academic leaders for their input and got plenty more insight. But at the end of the day, this is my list of the things that I'd rank as the most inspiring and significant achievements. Address your hate mail accordingly.

11. Soyuz MS-10 abort

In October 2018, a Soyuz spacecraft launched from Baikonur Cosmodrome carrying two humans, Russian cosmonaut Aleksey Ovchinin and NASA astronaut Nick Hague. A "bent" sensor on one of the rocket's four boosters that failed to properly signal stage separation, and this caused one of the booster stages to improperly separate from the rocket. This booster then struck the core of the rocket, causing a significant jolt and triggering one of the Soyuz spacecraft's automatic escape systems.

Fortunately, the hardy Soyuz capsule's escape system worked as intended. This is notable, because launch escape systems are rarely, if ever, tested on the actual flight vehicles ahead of missions. But in times of emergency, they are absolutely critical to the saving of human lives. In this case, the abort system triggered automatically, subjecting Ovchinin and Hague to a brief period of high gravity before they returned to Earth in a parabolic arc. This was a hugely dramatic moment in human spaceflight this decade. It's a testament to both the hardiness of the Russian crewed spacecraft design and the apparently declining reliability of the country's aerospace manufacturing processes.

Both astronauts launched successfully into orbit on March 2019.

10. Rocket Lab and the rest

As it turns out, building a rocket from scratch is difficult. Just one private company succeeded in flying a new small satellite launcher during the 2010s—Rocket Lab. After an initial test flight failed to reach orbit in 2017, the company has rattled off nine consecutive successful launches from its New Zealand spaceport. By the end of 2019, Rocket Lab was launching at a cadence of one mission about every month and a half. In fact, of US-based companies, Rocket Lab ranked second in total launches in 2019 with six—ahead of United Launch Alliance and only behind SpaceX.

One of the big space stories over the last five years has been the rise of dozens of new launch companies seeking to build rockets capable of launching between 100kg and 2 metric tons to low-Earth orbit. Many of these companies will fail—some, like Vector, already have—as the commercial and government market for dedicated launch can likely only support a few competitors. NASA has provided some modest support for these companies, but the majority of capital backing them has come from private investors.

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Trevor Mahlmann

Given that so many other companies are trying to make it in this market, Rocket Lab's rise has been remarkable, both from recognizing the potential market early (the company was founded in 2006, three years before SpaceX abandoned the Falcon 1 for the larger Falcon 9) and having the skills to develop a competent rocket and grow its business. In 2020, Rocket Lab plans to expand its launch operations to a second site at Wallops Island in Virginia and to continue working toward reusing its Electron first stages.