In 2012, the National Reconnaissance Office gave NASA two powerful spy satellites it no longer needed. The agency spent several months figuring out what to do with them. And now, finally, work is underway to bring the WFIRST fleet into reality.

The mirror in the telescopes are the same size as the one in Hubble, but adaptive optics and a wide field imager will give WFIRST 100 times the capabilities of the Hubble Space Telescope. It’s set for launch around 2024, far after the 2018 launch of the more powerful James Webb Telescope, but WFIRST fills a niche: it will serve as an instrument for finding dark energy.

Dark energy is a theoretical actor in the universe necessary for current models of the universe to work, yet it’s never been spotted. It accelerates the expansion of the universe and its indirect evidence has been found, but to date it has never been conclusively identified. It’s the stuff that makes up nearly 70 percent of the universe.

The telescopes will also hunt for planets in other solar systems by blocking out the light of their parent stars, a process called occultation. Similar processes have yielded some of the only direct images we have of planets in other solar systems, but better-than-Hubble optics and an orbit distant enough from Earth to avoid additional light glare will make WFIRST an excellent planet finding telescope. It may also allow for atmospheric measurements of Jupiter-to-Neptune class planets.

The WFIRST team will now begin to lay out mission goals, figure out on board instruments, and work toward a launch of the first scope sometime in the next decade. It will fill an important niche between the work of the Webb telescope, the planet-finding TESS, and other next-gen space observatories.

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