Set for launch in the mid 2020’s, the telescope - known as Roman - will be one of NASA’s most prolific planet hunters. The telescope will create enormous cosmic panoramas, helping us to answer questions about the evolution of our universe and perhaps delve deeper into new discoveries.
Astronomers expect the mission to find thousands of planets as it surveys a wide range of stars in the Milky Way. Using two different techniques, Roman will locate these potential new worlds, or exoplanets (a planet outside the solar system), by tracking the amount of light coming from distant stars over time.
Technique number one is known as gravitational microlensing, where a spike in light signals that a planet may be present. The second technique is called the transit method - if the light from a star dims periodically, it could be because there is a planet crossing the face of a star as it completes an orbit.
Throughout time the transit approach to finding exoplanets has been incredibly successful for NASA’s Kepler and K2 missions, which have discovered around 2,800 confirmed planets to date. By using these two methods to find new worlds, astronomers will capture an unprecedented view of the composition and arrangement of planetary systems across the galaxy.
“The fact that we’ll be able to detect thousands of transiting planets just by looking at microlensing data that’s already been taken is exciting,” said study co-author Jennifer Yee, an astrophysicist at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts. “It’s free science.”
Combining the results from both Roman’s microlensing and transiting planet searching techniques will be incredibly useful for scientists at NASA. It will provide a clearer insight into a more complete planet census, revealing worlds in large variety of sizes and orbits. The mission will offer the first opportunity to find large numbers of transiting planets located thousands of light-years away, helping astronomers at NASA learn more about the demographics of planets in different regions of the galaxy.