After years of preparatory studies, NASA is formally starting an astrophysics mission designed to help unlock the secrets of the universe—the Wide Field Infrared Survey Telescope (WFIRST). With a view 100 times bigger than that of NASA’s Hubble Space Telescope, WFIRST will survey large regions of the sky in near-infrared light to answer fundamental questions about the structure and evolution of the universe, and expand our knowledge of planets beyond our solar system—known as exoplanets.
WFIRST is the agency’s next major astrophysics observatory, following the launch of the James Webb Space Telescope in 2018. “WFIRST has the potential to open our eyes to the wonders of the universe, much the same way Hubble has,” says John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington. “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.”
The telescope will carry a wide-field instrument for surveys and a coronagraph instrument designed to block the glare of individual stars, revealing the faint light of planets orbiting around them. By blocking the light of the host star, the coronagraph will enable detailed measurements of the chemical makeup of planetary atmospheres. Comparing data across many worlds will allow scientists to better understand the origin and physics of these atmospheres and to search for chemical signs of environments suitable for life.
“WFIRST is designed to address science areas identified as top priorities by the astronomical community,” says Paul Hertz, director of NASA’s Astrophysics Division in Washington. “The wide-field Instrument will give the telescope the ability to capture a single image with the depth and quality of Hubble, but covering 100 times the area. The coronagraph will provide revolutionary science, capturing the faint, but direct images of distant gaseous worlds and super-Earths.”
Employing multiple techniques, astronomers will also use WFIRST to track how dark energy and dark matter have affected the evolution of our universe. Dark energy is a mysterious, negative pressure that has been speeding up the expansion of the universe, while dark matter is invisible material that makes up most of the matter in our universe.
By measuring the distances of thousands of supernovae, astronomers can map in detail how cosmic expansion has increased with time. WFIRST can precisely measure the shapes, positions and distances of millions of galaxies to track the distribution and growth of cosmic structures, including galaxy clusters and the dark matter accompanying them.
“In addition to its exciting capabilities for dark energy and exoplanets, WFIRST will provide a treasure trove of exquisite data for all astronomers,” says Neil Gehrels, WFIRST project scientist at NASA’s Goddard Space Flight Center in Greenbelt MD. “This mission will survey the universe to find the most interesting objects out there.”
WFIRST is slated to launch in the mid-2020s. The observatory will begin operations after traveling to a gravitational balance point known as Earth-Sun L2, which is located about one million miles from Earth in a direction directly opposite the sun.
WFIRST is managed at Goddard, with participation by the Jet Propulsion Laboratory (JPL) in Pasadena CA, the Space Telescope Science Institute in Baltimore, the Infrared Processing and Analysis Center, also in Pasadena, and a science team comprised of members from US research institutions across the country.