Astronomers are developing a new instrument to detect faint dust clouds around other stars, many of which may hide Earth-like planets with conditions suitable to life.
Astronomers at the University of Arizona are part of an international team of exoplanets hunters funded by NASA.
The team is developing new technology that would dramatically improve the odds of discovering planets with conditions suitable for life – such as having liquid water on the surface.
Terrestrial planets orbiting nearby stars often are concealed by vast clouds of dust enveloping the star and its system of planets.
Our solar system, too, has a dust cloud, which consists mostly of debris left behind by clashing asteroids and exhaust spewing out of comets when they pass by the Sun.
“Current technology allows us to detect only the brightest clouds, those that are a few thousand times brighter than the one in our solar system,” said Denis Defrere, from the UA’s department of astronomy and instrument scientist of the Large Binocular Telescope Interferometer (LBTI).
He explained that while the brighter clouds are easier to see, their intense glare makes detecting putative Earth-like planets difficult, if not impossible.
“We want to be able to detect fainter dust clouds, which would dramatically increase our chances of finding more of these planets,” Defrere said.
“If you see a dust cloud around a star, that’s an indication of rocky debris, and it increases the likelihood of there being something Earth-like around that star,” said Phil Hinz, an associate professor of astronomy at the UA’s Steward Observatory.
“From previous observations, we know that these planets are fairly common. We can expect that if a space telescope dedicated to that mission were to look around a certain area of sky, we’d expect to find quite a few,” he said.
Hinz and Defrere are working on an instrument that will allow astronomers to detect fainter clouds that are only about 10 times – instead of several thousand times – brighter than the one in our solar system.
The team is in the middle of carrying out tests to demonstrate the feasibility of these observations using both apertures of the Large Binocular Telescope, or LBT, in Arizona.
The project aims at determining how difficult it would be to achieve the desired results before committing to a billion-dollar space telescope mission.
According to Hinz, NASA’s goal is to be able take a direct picture of Earth-like, rocky planets and record their spectrum of light to analyse their composition and characteristics such as temperature, presence of water and other parameters.