In the last decade, telescopes have discovered thousands of planets outside of our solar system, called exoplanets, giving us a dazzling glimpse of possible worlds beyond our own. However, the next generation telescopes will be able to explore tens of thousands of exoplanets. In fact, it will be able to do even more, just like the upcoming NASA Nancy Grace Rome Space Telescope.
Rome will use a method called micro-sensing to find new planet candidates. The method will enable the telescope to look at a large number of stars and watch from our perspective of the world when one star passes in front of another. When this happens, the gravity of the foreground star will bend the light emitted by the background star, causing a small fluctuation in brightness. Thus, the telescope will enable scientists to learn about the foreground star, including whether it will host planets.
Roman Space Telescope may be the best at planet exploration
The difficulty with this method is stated to be that it is extremely rare for the two stars to line up exactly this way. To find the two listed stars, the telescope must observe millions of stars to increase the chance of seeing one pass in front of the other.
Astrophysicist Benjamin Montet, Scientific Lecturer at the University of New South Wales in Sydney, explains: “Microlensing events are rare and fast, so you need to look at many stars over and over and measure their brightness changes precisely to detect them. “These are the same things you need to do to find transiting planets, so by creating a robust micro-sensing research, Roman will prepare a nice transitional survey,” he said.
The traversal method looks for decreases in the brightness of a planet star. This provides scientists with an additional method to explore more exoplanets from the same data.
The method is cited as the best for finding planets close to the stars. Microlensing is said to be the best for finding planets far from their stars.
Jennifer Yee, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics in Cambridge, is the co-author of the study; “It’s exciting that we can detect thousands of transiting planets just by looking at the microlens data already received,” she says.
A research paper from Montet estimates that Roman could detect up to 100,000 planets using microlens and explore even more using the transit method. It is aimed to launch the space telescope as soon as possible.