The European Southern Observatory (ESO) has announced the first successful SPECULOOS observations to find potentially habitable planets outside the solar system.
The SPECULOOS project, or Search for habitable Planets EClipsing ULtra-cool Stars, aims to search for and register Earth-sized exoplanets from nearby ultracold dwarfs. As part of the project, four telescopes were installed on Mount Paranal. The place was not chosen by chance: an almost cloudless sky and a stable dry climate create ideal conditions for astronomical observations. For example, the famous Very Large Telescope, the main instrument of the European Southern Observatory, also works there. The SPECULOOS telescopes are named after Jupiter's four Galilean moons - Io, Europa, Ganymede and Callisto - and the main mirror is one meter in diameter.
The main goal of SPECULOOS will be to search for potentially habitable Earth-sized planets near ultracold stars or brown dwarfs, whose planets are still largely poorly understood. Although the process of observing these faint stars is quite difficult, scientists believe that they make up about 15% of the stars in the studied part of the universe. SPECULOOS is designed to explore thousands of such stars, including the nearest, brightest and smallest, in search of habitable Earth-sized planets.
In the search for exoplanets, the transit method will be used. When the planet is between the telescope and the star, it will block part of the star's disk. A "mini-eclipse" will occur, which will greatly weaken its radiation. In small stars, exoplanet transits are more noticeable, since most of the star's light is "obscured" - and such "eclipses" are much easier to register than in bright stars.
Four SPECULOOS telescopes / © SPECULOOS Team
Fun fact: Speculoos is also the name of a spicy biscuit from Belgium, where the chief project manager Michaël Gillon is from. He was also the lead researcher for the discovery of the TRAPPIST-1 system, which consists of seven rocky planets the size of Earth and potentially habitable.
Scientists have already received the first images from SPECULOOS - astronomers call this the "first light". Direct scientific observations are scheduled for January 2019.
Left: central portion of the Eta Carinae nebula, the first light from the Europa telescope; right: The Horsehead Nebula, the first light from Callisto's telescope. / © ESO
The researchers note that by looking at small ultracold stars, the highly sensitive SPECULOOS instruments will be able to detect Earth-sized planets in the habitable zones of stars. Until today, only a few exoplanets discovered using the transit method have been registered, so researchers have high hopes for this project.