"WFIRST has the potential to open our eyes to the wonders of the universe, much the same way Hubble has.”
It's finally official: NASA's next major telescope project will be the innovative Wide Field Infrared Survey Telescope (WFIRST). The space telescope is projected to launch to the gravitational eddy known as Earth-Sun L2—which is located one million miles from Earth, in the direction opposite the Sun—sometime in the 2020s.
The telescope's wide field instrument is expected to yield new insights into mysterious phenomena like dark energy and dark matter, while also bolstering the search for potentially habitable planets outside the Solar System.
In this way, the project has been seen as an instrument that embodies "the best of both worlds" when it comes to observing the universe. Most telescopes specialize in either wide shots of the skies, or in extreme close-ups of individual objects, but WFIRST will be a multipurpose workhorse capable of excelling at either extreme.
Its 7.8-foot aperture will capture images 100 times larger than those produced by the Hubble Space Telescope, without any compromise in depth or resolution. Meanwhile, its onboard coronagraph will shade out the glare of distant stars so precisely that scientists expect to unravel the atmospheric makeup of the planets orbiting them.
"WFIRST has the potential to open our eyes to the wonders of the universe, much the same way Hubble has," said John Grunsfeld, astronaut and associate administrator of NASA's Science Mission Directorate, in a NASA statement.
"This mission uniquely combines the ability to discover and characterize planets beyond our own solar system with the sensitivity and optics to look wide and deep into the universe in a quest to unravel the mysteries of dark energy and dark matter."
To that point, WFIRST will continue the hard work of cinching more observational evidence to buttress Albert Einstein's theory of general relativity, published 101 years ago. Much like the recent direct detection of gravitational waves by LIGO, WFIRST aims to dig up some real empirical dirt on dark energy, which could explain whether "it is an unknown form of energy or if it's a modification of general relativity," according to Yun Wang, a senior research scientist on the mission.
In keeping with the relativistic theme, WFIRST will also rely partly on gravitational microlensing in order to hunt down Earth-sized exoplanets. Microlensing can occur when stars pass in front of each other from our perspective on Earth, resulting in the gravitational field of the foreground star warping spacetime in such a way that the background star appears enlarged.
Much like large-scale gravitational lensing—for instance, when full galaxies behave like microscopes—the effect allows astronomers to see the background scene with precision and clarity that would not be possible without this handy cosmic shortcut.
Preparatory work on WFIRST has been ongoing for a few years, but it was only this week that NASA's Goddard Space Flight Center announced that the mission is officially a go, complete with $90 million in funding for the year 2016 thanks to the omnibus spending bill passed in December—way more than the $14 million requested for the mission by NASA. The entire project is expected to cost about $2.3 billion.
"We have made every one of our milestones on schedule so far," said Paul Hertz, director of NASA's astrophysics division, according to SpaceNews. "We're making fabulous progress in keeping on that plan that will enable us to do WFIRST in the shortest possible period."