The planet is likely tidally locked, meaning one side always faces the sun while the other is shrouded in darkness.
An international team of astronomers has unveiled a fascinating discovery about an Earth-sized exoplanet orbiting an ultracool dwarf star. The project is named as SPECULOOS and the exoplanet, is known as SPECULOOS-3 b. This offers new insights into the complexities of planetary systems around red dwarf stars.
DISCOVERY AND CHARACTERISTICS
Michaël Gillon from the University of Liège, discovered SPECULOOS-3 b, an Earth-sized planet located 55 light-years from Earth. The host star, is an ultracool dwarf star, only the size of Jupiter and twice as cold as our Sun. The discovery is particularly significant as it marks only the second time astronomers have found a planetary system around a red dwarf star, the first being the renowned Trappist-1 system.
SPECULOOS-3 b stands out for several reasons. Firstly, its orbit around the star is incredibly short, taking just 17 hours to complete a full revolution. This rapid orbit implies that the planet is tidally locked, meaning one side perpetually faces the star while the other side remains in constant darkness. This creates a stark contrast in temperature and illumination between the planet’s hemispheres.
CONDITIONS AND HABITABILITY
Émeline Bolmont, an assistant professor in the Astronomy department at the University of Geneva (UNIGE) and a member of the SPECULOOS team, highlighted the advantages of studying red dwarf stars,
“The small size of these stars makes it easier to detect small Earth-size planets around them and observe any planetary atmospheres,” Bolmont said. Red dwarf stars, despite their cooler temperatures and dimmer light compared to our Sun, are considered ideal for studying planetary habitability due to their stability and the prevalence of Earth-sized planets in their habitable zones.
However, life on SPECULOOS-3 b faces significant challenges. According to a NASA news release from May 15, the planet is subjected to high levels of radiation from its star, likely stripping it of any atmosphere. The extreme radiation levels, combined with the planet’s synchronous rotation, suggest a harsh environment on the day side, with scorching temperatures, while the night side is locked in frigid darkness.
THE STAR: SPECULOOS-3
The host star, SPECULOOS-3, presents a stark contrast to our Sun. It has a surface temperature of about 4,760 degrees Fahrenheit (2,627 degrees Celsius), making it several thousand degrees cooler than the Sun. Its dimness and small size play a crucial role in the detection and study of planets like SPECULOOS-3 b. These characteristics make ultracool dwarfs ideal targets for astronomers searching for Earth-like exoplanets.
IMPLICATIONS FOR FUTURE RESEARCH
The discovery of SPECULOOS-3 b opens exciting avenues for future research. The planet is a prime candidate for follow-up observations by the James Webb Space Telescope (JWST). Such observations could provide deeper insights into the planet’s atmosphere, if it exists, and its surface mineralogy. Understanding these factors could help scientists piece together the history of this planetary system and its potential for habitability.
Steve B. Howell, one of the planet’s discoverers at NASA Ames Research Center in Silicon Valley, expressed optimism about the future of exoplanet research. “We’re making great strides in our study of planets orbiting other stars. We have now reached the stage where we can detect and study Earth-sized exoplanets in detail. The next step will be to determine whether any of them are habitable, or even inhabited,” Howell said.
PUBLISHED FINDINGS
The team’s findings were published on May 15 in the journal Nature Astronomy, highlighting the significance of this discovery in the broader context of exoplanetary science. The SPECULOOS project, named after the network of telescopes used for this research, continues to push the boundaries of our understanding of planetary systems around ultracool dwarf stars.
CONCLUSION
The discovery of SPECULOOS-3 b represents a major milestone in the search for Earth-like planets around red dwarf stars. As technology advances and telescopes like JWST begin to provide more detailed observations, the possibility of finding habitable, or even inhabited, worlds continues to grow. This discovery not only enhances our understanding of the Universe but also brings us one step closer to answering the age-old question of whether we are alone in the cosmos.
