On August 30th at 11.26 Universal Time, the Nancy Grace Roman Space Telescope—NASA’s newest eye in the sky—took off from the Kennedy Space Centre, in Florida, aboard a SpaceX Falcon Heavy rocket. The telescope, named after NASA’s first chief astronomer, is now heading for a parking spot in orbit around 1.6m kilometres from Earth. From there, it will provide astronomers with an unprecedented view of the universe.
Two particular gadgets will assist in this. One is the Wide Field Instrument (WFI), a 300-megapixel camera that will snap pictures in both visible light and infrared. It will thus be able to see distant galaxies whose light has been stretched to infrared wavelengths by the expanding universe. And, as its name suggests, the WFI’s field of view is huge—over 100 times larger than the camera of its original predecessor, the Hubble Space Telescope.
Paradoxically, two of the WFI’s targets will not appear in any of its photos. At least not directly. They are dark matter and dark energy—a pair of mysterious phenomena that reveal themselves only through the ways in which they bend and stretch the fabric of spacetime. Astronomers know they are there, but not what they actually are (though a particle of dark matter may just have been detected). They will therefore use the WFI’s souped-up optics to search for clues by tracking how these cosmic oddities have influenced the universe’s other matter over the course of its history.
