According to the latest space news published by New York Post (USA), a group of international astronomers has discovered two new super-Earths orbiting a cold dwarf star located just 100 light-years from Earth.
Discovery of 2 Super-Earths Near the Solar System: “Goldilocks Zone for Life”
These are two exoplanets that scientists have identified, one of which may have the necessary conditions for life to develop, or in other words, it is located in the “habitable zone” (or Goldilocks zone).
The two exoplanets have been named LP 890-9b and LP 890-9c, discovered at a relatively close distance of just 100 light-years, and they orbit around the host star named LP 890-9.
The two exoplanets are named LP 890-9b and LP 890-9c.
Based on previous findings from NASA’s Transiting Exoplanet Survey Satellite (TESS), researchers at the University of Birmingham in the UK used their SPECULOOS telescope – short for “Search for habitable Planets EClipsing Ultrafaint Stars (SPECULOOS)” – to confirm the potential habitability of these two exoplanets.
Accordingly, astronomers have gathered important preliminary information about the two super-Earths as follows:
- The exoplanet closest to the host star is LP 890-9b, which is about 30% larger than Earth and orbits the dwarf star in just 2.7 Earth days. Its orbit is only 2.8 million km from the red dwarf star. According to scientists, it receives 4.1 times more heat and light from its star compared to Earth.
- The second exoplanet, named LP 890-9c, is slightly larger than LP 890-9b, about 40% larger than our Earth; its orbit is at a distance of 6 million km from the host star. LP 890-9c completes its orbit in about 8.5 Earth days.
Astronomers believe that this second planet (LP 890-9c) lies within the “habitable zone” of its host star, where it is neither too hot nor too cold to support the existence of liquid water on its surface.
According to astronomers, the daytime hemisphere of LP 890-9c receives about 90% of the heat and light that our planet receives from the Sun. This means that if there is a suitable atmosphere, liquid water could exist on the surface.
To test this hypothesis, in the future, astronomers hope to use NASA’s James Webb Space Telescope to study this system. If LP 890-9c has an atmosphere, the telescope will be able to find traces of it and also attempt to determine its chemical composition.
Illustration of two super-Earths orbiting a red dwarf star. (Image: Mark Garlick / Science Photo Library via Getty Images).
Characteristics of the stars and planets in the LP 890-9 system. (Source: Adeline Deward).
Not long ago, TESS also contributed to the discovery of two new super-Earths. The first is a super-Earth named TOI-1452b, located in the Draco constellation, 100 light-years away from Earth. Scientists initially suggest that TOI-1452b could be a vast ocean world; next is the super-Earth TOI-836b, located 90 light-years away. Although it has characteristics of a super-Earth, TOI-836b is a scorching planet with surface temperatures reaching 500 degrees Celsius.
“The TESS space telescope searches for exoplanets (planets outside the Solar System) using the transit method by monitoring the brightness of thousands of stars simultaneously, looking for small dips that may be caused by planets transiting in front of their host stars,” said Laetitia Delrez, an exoplanet scientist at the University of Liège (Belgium) and the lead author of the detailed discovery report.
“The work of TESS is the first step. The second step, equally important for astronomers, is to follow up with ground-based telescopes – which is often essential – to confirm the planetary nature of the detected candidates and to refine measurements of their sizes and orbital characteristics,” the author added.
This follow-up work is particularly important in the case of cold stars like LP 890-9 (the host star of the two newly discovered super-Earths) because most of their light is recorded in the form of infrared light, for which TESS’s sensitivity is limited.
This limitation of TESS is shared by the telescopes of the SPECULOOS project, which are located in Chile and on Tenerife, an island just west of Morocco. These types of telescopes are equipped with cameras that are very sensitive to near-infrared light.
Scientific Community Excited for Upcoming Missions
Michaël Gillon, an astronomer at the University of Liège and the principal investigator of the SPECULOOS project, stated: “The goal of SPECULOOS is to search for potentially habitable planets around some of the smallest and coolest stars in the vicinity of the Sun. This strategy is driven by the fact that such planets are particularly suited for detailed studies of their atmospheres and searching for possible chemical signatures of life with large observatories, such as NASA’s James Webb Space Telescope (JWST).”
Michaël Gillon compared the discovery of the two super-Earths LP 890-9b and LP 890-9c orbiting the cold star LP 890-9 to the search for exoplanets in the TRAPPIST-1 system.
The TRAPPIST-1 system. (Source: NASA).
Among the seven known exoplanets orbiting the TRAPPIST-1 system, three planets lie within the “habitable zone,” making the TRAPPIST-1 system a primary target for astronomers to investigate further.
The fact that one of the newly discovered worlds occupies the habitable zone of the host star LP 890-9 makes further investigation of this system equally intriguing. This is a significant draw for the scientific community!
“This allows us to observe more and learn whether the planet LP 890-9c has an atmosphere, and if it does, we will continue to study its nature and assess its habitability,” said Professor Amaury Triaud, an astrophysicist at the University of Birmingham (UK) and the head of the SPECULOOS working group.
The scientific community will look for factors contributing to the potential for life, such as the size and distance of the exoplanet from its host star, as well as the size and temperature of the star itself.
“The habitable zone is a concept whereby a planet with geological and atmospheric conditions similar to Earth will have surface temperatures that allow water to remain in a liquid state for billions of years,” Professor Amaury Triaud explained.
Our Earth lies in the Goldilocks zone. (Image: Getty Images / Science Photo Library).
Next, scientists hope to study the atmosphere of SPECULOOS-2c, possibly with JWST, which recently discovered carbon dioxide in the atmosphere of an exoplanet.
“It is crucial to discover as many temperate worlds as possible to study the diversity of exoplanet climates; ultimately, the goal is to understand better the location to measure the frequency of life emergence in the universe,” Amaury Triaud concluded.
The group’s research was published on Wednesday (September 6) in the journal Astronomy & Astrophysics.
