Suppose you were an astronomer and someone offered you, at no cost, two giant mirrors for telescopes in space, each valued at more than 250 million dollars. Sound too good to be true? It actually happened at NASA.
In January 2011, the National Reconnaissance Office, a U.S. spy agency, offered NASA two, surplus 94-inch diameter telescope mirrors with related hardware. At that time, NASA was planning a space telescope with a 52 inch-diameter main mirror called WFIRST, an acronym that stood for Wide-Field Infrared Survey Telescope. A larger mirror exactly matching NASA’s needs would greatly enhance the scientific return from such a telescope. So, in 2012 NASA revised the plan to use one of these 94-inch diameter mirrors. After more than a decade of development, this telescope was launched into space on August 30, 2026.
WFIRST was renamed to honor NASA’s first Chief Astronomer, Nancy Grace Roman, a leading 20th Century scientist and early advocate for telescopes in space. The Roman Space Telescope has the same diameter mirror as the famous Hubble Space Telescope, but a field of view that is 100 times greater, allowing for expansive surveys of the universe at near infrared and visible wavelengths. Although it’s a survey telescope, the Roman Space Telescope has the same high resolution as the Hubble Space Telescope, thanks to its advanced, 300-megapixel camera. In about 3 months the Roman Telescope will enter a “halo orbit” about the Sun-Earth L2 Lagrange point, roughly 1 million miles away. At the L2 Lagrange point, the gravitational attractions of the Sun and Earth are balanced, which will allow the Telescope to remain in that region of space with little use of propellent. From this distant orbit, the Roman Telescope will continuously observe the entire sky with no interference from Earth or from Earth satellite constellations that hinder telescopes in lower orbits, like the Hubble Space Telescope.
The Roman Space Telescope will study such astronomical mysteries as the nature of dark energy and dark matter, black holes, microlensing, supernova explosions, and the evolution of galaxies. Also, with its coronagraph instrument and high infrared sensitivity, the Telescope will directly image exoplanets, planets orbiting distant stars. And the Roman Telescope will conduct surveys that will guide future research with the James Webb Space Telescope, the largest telescope in space. Amazingly, data from the Roman Space Telescope will be released to the public immediately after it’s obtained.
NASA still has that other 94-inch mirror from the National Reconnaissance Office, but currently there are no definite plans for using it. How do you think it should be used? Meanwhile, let’s hope for a successful journey of discovery for the Roman Space Telescope, so that we can learn more about our fascinating Universe!
Music written and produced by Kenny Mihelich (ma-HELL-itch). Western Slope Skies is produced by the Colorado Mesa University Astronomy Club, the Western Slope Dark Sky Coalition, and KVNF Community Radio. This feature was written and voiced by Art Trevena.