A Planet That May Also Be Blue – 100 Light Years Away: Astronomers have discovered an exoplanet in a binary star system that may be completely covered by a deep ocean. TOI-1452 b is slightly larger than Earth and orbits one of two stars at a distance that could allow for liquid surface water. Its density suggests a high proportion of light matter – possibly water. The sharp look with the James Webb Space Telescope should now reveal more mysteries from TOI-1452 b, scientists say.
Space is full of planets: Astronomers have already discovered thousands of celestial bodies around distant stars. Meanwhile, interest is therefore focused on particular specimens. Research is particularly focused on exoplanets that have characteristics similar to those of our cosmic homeland. A central aspect is the blue treasure of the earth. As is well known, liquid water has become for us the elixir of life: it is the prerequisite for the existence of all terrestrial organisms and it is believed that the history of their evolution began in the oceans. Now the team of astronomers led by University de Montréal doctoral student Charles Cadioux is adding particularly promising candidates to the small collection of potential water worlds.
On the exoplanet’s path, researchers brought in data from NASA’s TESS space telescope, which scans the sky for planetary systems in our cosmic neighborhood. In a system about 100 light-years from Earth in the constellation Draco, TESS detected interesting signs: every eleven days there was a slight decrease in brightness, apparently due to the passage of a planet. The researchers then followed this lead in more detail. As more and more interesting aspects emerged, the team used a variety of astronomical facilities and instruments to collect as detailed information as possible.
Exciting Features
First, it became clear that the star system consists of not one, but two stars that are smaller than our Sun. They orbit each other at a distance of about two and a half times the distance between the Sun and Pluto. So he initially only saw the TESS telescope as a single point of light. But a camera installed at Canada’s Observatoire du Mont-Mégantique (OMM) was eventually able to resolve the signal to separate the two objects. It also showed that the exoplanet orbits the star of both, TOI-1452. According to calculations, it gains the amount of energy in this process to create temperate conditions that allow liquid water to surface.
The transit data showed that the planet is about 70 percent larger than Earth. The radial velocity method was then used to determine the planet’s mass, which allows conclusions to be drawn about a planet’s characteristics based on its gravitational effect on its host star. OMM used the “SPIRou” instrument, which is particularly suitable for studying low-mass stars such as TOI-1452, as it operates in the infrared spectrum, where these stars shine the most. As the team reports, data analysis revealed TOI-1452’s mass to be about five times that of Earth.
an ocean planet?
“Its radius and mass suggest that it is much less dense than a planet that, like Earth, is mostly metal and rock,” says Cadiaux. The features can be explained by the fact that a large part of the mass consists of lighter material. A plausible explanation would be water. “TOI-1452b is one of the best ocean planet candidates ever found,” says Cadiox. Model simulations by scientists have shown that TOI-1452 b may contain up to 30 percent water. That would be a clear water world. Because although Earth is sometimes called the Blue Planet because about 70 percent of its surface is covered by oceans, it is actually a dry planet: water actually only makes up about 1 percent of Earth’s mass.
TOI-1452b is now an ideal candidate for further observations with the James Webb Space Telescope, scientists say. It is close enough to Earth that researchers hope to study its atmosphere to see if it is indeed an oceanic planet. Fortunately, it is in an area of the sky that the Webb telescope can see year-round. “Our planned investigation with the Webb telescope will make a decisive contribution to a better understanding of TOI-1452b,” says René Doyn of the Université de Montréal. “As soon as possible, we will book time on the web to see this mysterious world.”
Source: University of Montreal, Professional article: The Astronomical Journal, doi: 10.3847/1538-3881/ac7cea