NASA’s James Webb Space Telescope is late to its own party, and it’s not just a little bit late. NASA originally planned to have the spacecraft ready to roll as early as 2007, but a laundry list of setbacks (and stupid human errors on the part of manufacturer Northrop Grumman) have pushed the project back by over a decade and roughly 20 times its original cost.

With that much cash dumped into a project, you can bet that NASA is eager to see some hints of serious progress, especially with its tentative 2021 launch window rapidly approaching. The good news is that half of the telescope just completed a round of testing at its manufacturing facility, besting a vacuum chamber designed to put it through conditions it would experience while in space.

The telescope is being built in two parts. One half contains the telescope itself as well as various scientific instruments, and the other half is the spacecraft platform which allows it to move and maintain its orbit. The spacecraft half is the portion that just completed its vacuum chamber testing, which put it up against temperatures ranging from negative 235 degrees Fahrenheit to 215 degrees Fahrenheit.

“The teams from Northrop Grumman and NASA Goddard Space Flight Center are to be commended for a successful spacecraft thermal vacuum test, dedicating long hours to get where we are now,” Jeanne Davis, James Webb program manager, said in a statement. “This incredible accomplishment paves the way for the next major milestone, which is to integrate the telescope and the spacecraft elements.”

The news is a long time coming, but it’s definitely a big step in the James Webb program. Ensuring that all the components will work as planned once they make it into space is, of course, crucial, but plenty of hurdles still have to be scaled before the telescope is ready to head skyward. Integrating all of the components takes time, and new issues could crop up at any moment. Let’s hope the 2021 date sticks and NASA isn’t forced to delay it yet again.

Mike Wehner has reported on technology and video games for the past decade, covering breaking news and trends in VR, wearables, smartphones, and future tech. Most recently, Mike served as Tech Editor at The Daily Dot, and has been featured in USA Today, Time.com, and countless other web and print outlets. His love of reporting is second only to his gaming addiction.