When you buy through links on our articles, Future and its syndication partners may earn a commission.An illustration of the Nancy Grace Roman Space Telescope. | Credit: NASAOnce NASA’s Nancy Grace Roman Space Telescope launches in the next 12 to 18 months, it will be on its way toward outdoing scientists’ initial expectations. Researchers have confirmed that Roman should be able to measure enormous seismic waves rippling across the surfaces of more than 300,000 red giant stars.Roman is a survey telescope, with an 8-foot (2.4-meter) mirror like the Hubble Space Telescope, but a field of view 100 times larger. Besides studying dark matter and dark energy, one of Roman’s core surveys will be the Galactic Bulge Time-Domain Survey, in which millions of stars in the central bulge of the Milky Way galaxy will be studied, principally to look for exoplanets. The idea is to use gravitational microlensing as a planet-finding device. Gravitational lensing is a technique often used in astrophysics to study distant objects; due to the way spacetime warps as per general relativity, some huge objects in space (like galaxy clusters, for instance) warp light traveling nearby, therefore magnifying, distorting and duplicating the source of that light as seen through our telescopes. Gravitational microlensing refers to gravitational lensing on smaller scales, like that of a planet.AdvertisementAdvertisementStaring at the hundreds of millions of stars in the bulge, Roman will occasionally see some flicker, brightening temporarily as the gravity of an unseen foreground planet magnifies their light before moving out of alignment. However, microlensing is not the only phenomenon that can cause a star’s light to flicker. Stars are constant, writhing masses of vast convective bubbles rising to their seething surfaces. Oscillations also reverberate through their interiors, shaking them up. The frequency of these oscillations depends upon the temperature, structure and composition of a star, and when the oscillations break through to the surface they can cause a star to temporarily, subtly brighten.The science of studying these stellar oscillations is called asteroseismology, and the frequency of the oscillations can reveal the masses, sizes and ages of the stars for which they are observed. In turn, understanding stars better can inform astronomers as to some of the properties of the planets that orbit them.”With asteroseismic data we’ll be able to get a lot of information about exoplanets’ host stars and that will give us a lot of insight on exoplanets themselves,” study leader Trevor Weiss of California State University, Long Beach, said in a statement.The Kepler Space Telescope, which hunted for exoplanets by watching for transits, was able to make asteroseismological measurements of 150,000 stars. In assessing whether Roman will be able to do the same, Weiss’ team applied the Kepler dataset to models of Roman’s observational capabilities. In particular, they discovered that Roman will be adept at detecting stellar oscillations on red giant stars, which are both luminous (making them easier to detect) and have a high frequency of oscillation with a period ranging from hours to days. This is a good match for Roman’s Galactic Bulge Time-Domain Survey, which will keep a steady eye on hundreds of millions of stars in the Milky Way galaxy’s bulge every 12 minutes over half-a-dozen 70.5-day stretches, meaning that it will be attuned to the red giants’ vibrations.AdvertisementAdvertisement”Asteroseismology with Roman is possible because we don’t need to ask the telescope to do anything it wasn’t already planning to do,” said Marc Pinsonneault of Ohio State University. “The strength of the Roman mission is remarkable: it’s designed in part to advance exoplanet science …
