May 2, 2024

Water World: Astronomers Discover an Extrasolar World That May Be Entirely Covered in a Deep Ocean

The astronomers believe it could be an “ocean planet,” a planet totally covered by a thick layer of water. Even then, it took more than 50 hours of observation to approximate the worlds mass, which is thought to be almost 5 times that of Earth.
Even though we sometimes call it the Blue Planet since about 70% of its surface is covered by ocean, water actually only makes up a negligible portion of its mass– less than 1%.
Some of these worlds have a density that can just be described if a big fraction of their mass is made up of lighter materials than those that make up the internal structure of the Earth such as water. It is one of the few recognized temperate worlds that display attributes consistent with an ocean world.

Cadieux and his team explain the observations that elucidated the nature and qualities of this unique exoplanet in a post released on August 12 in The Astronomical Journal.
Creative representation of the surface of TOI-1452 b, which could be an “ocean planet”, i.e. a world totally covered by a thick layer of liquid water. Credit: Benoit Gougeon, Université de Montréal
” Im extremely proud of this discovery due to the fact that it reveals the high calibre of our researchers and instrumentation,” stated René Doyon, Université de Montréal Professor and Director of iREx and of the Observatoire du Mont-Mégantic (OMM). “It is thanks to the OMM, a special instrument created in our labs called SPIRou, and an innovative analytic method developed by our research group that we had the ability to discover this unique exoplanet.”
It was NASAs area telescope TESS, which surveys the entire sky in search of planetary systems near to our own, that put the astronomers on the trail of this exoplanet. Based upon the TESS signal, which showed a small decrease in brightness every 11 days, scientists forecasted a planet about 70% larger than Earth.
Charles Cadieux comes from a group of astronomers that does ground follow-up observations of candidates recognized by TESS in order to confirm their planet type and qualities. He utilizes PESTO, an electronic camera set up on the OMMs telescope that was developed by Université de Montréal Professor David Lafrenière and his Ph.D. student François-René Lachapelle.
A global team of astronomers has discovered an exoplanet that could be totally covered in water. Credit: Benoit Gougeon, Université de Montréal
” The OMM played an important function in validating the nature of this signal and estimating the planets radius,” discussed Cadieux. “This was no routine check. We had to make sure the signal found by TESS was really brought on by an exoplanet circling TOI-1452, the biggest of the two stars in that binary system.”
The host star TOI-1452 is much smaller than our Sun and is one of 2 stars of comparable size in the binary system. The 2 stars orbit each other and are separated by such a little distance– 97 huge systems, or about 2 and a half times the distance between the Sun and Pluto– that the TESS telescope sees them as a single point of light. PESTOs resolution is high enough to distinguish the two things, and the images revealed that the exoplanet does orbit TOI-1452, which was validated through subsequent observations by a Japanese team.
Ingenuity at work
To figure out the worlds mass, the astronomers then observed the system with SPIRou, an instrument set up on the Canada-France-Hawaii Telescope in Hawaii. Created in big part in Canada, SPIRou is ideal for studying low-mass stars such as TOI-1452 because it operates in the infrared spectrum, where these stars are brightest. Even then, it took more than 50 hours of observation to approximate the worlds mass, which is thought to be nearly five times that of Earth.
Étienne Artigau and Neil Cook, researchers likewise with iREx at the Université de Montréal, played an essential function in evaluating the information. They developed an effective analytic method efficient in finding the planet in the data collected with SPIRou. “The LBL technique [for line-by-line] enables us to clean up the data gotten with SPIRou of many parasite signals and to expose the weak signature of worlds such as the one discovered by our team,” discussed Artigau.
The team likewise consists of Quebec researchers Farbod Jahandar and Thomas Vandal, 2 Ph.D. trainees at the Université de Montréal. Jahandar analyzed the host stars composition, which works for constraining the planets internal structure, while Vandal was associated with evaluating the information gathered with SPIRou.
A watery world
The exoplanet TOI-1452 b is most likely rocky like Earth, its radius, density, and mass recommend a world very various from our own. Earth is essentially a really dry planet. Even though we often call it the Blue Planet because about 70% of its surface area is covered by ocean, water in fact just makes up a negligible fraction of its mass– less than 1%.
Water might be a lot more abundant on some exoplanets. In the last few years, astronomers have identified and figured out the radius and mass of lots of exoplanets with a size between that of Earth and Neptune (about 3.8 times bigger than Earth). Some of these planets have a density that can only be explained if a big fraction of their mass is made up of lighter products than those that make up the internal structure of the Earth such as water. These theoretical worlds have actually been dubbed “ocean planets.”
” TOI-1452 b is among the finest prospects for an ocean world that we have actually discovered to date,” said Cadieux. “Its radius and mass suggest a much lower density than what one would expect for a planet that is essentially comprised of metal and rock, like Earth.”
The University of Torontos Mykhaylo Plotnykov and Diana Valencia are professionals in exoplanet interior modeling. Their analysis of TOI-1452 b shows that water may comprise as much as 30% of its mass, a proportion similar to that of some natural satellites in our Solar System, such as Jupiters moons Ganymede and Callisto, and Saturns moons Titan and Enceladus.
To be continued …
An exoplanet such as TOI-1452 b is a perfect candidate prospect further observation with the James Webb Space Telescope, or Webb for shortBrief It is one of the few recognized temperate planets that show characteristics consistent with an ocean world.
” Our observations with the Webb Telescope will be vital to much better understanding TOI-1452 b,” said Doyon who overviewed the conception of James Webbs part Near Infrared Imager and Slitless Spectrograph (NIRISS). “As soon as we can, we will book time on Webb to observe this terrific and weird world.”
Reference: “TOI-1452 b: SPIRou and TESS expose a super-Earth in a temperate orbit transiting an M4 dwarf” by Charles Cadieuxg, René Doyon, Mykhaylo Plotnykov, Guillaume Hébrard, Farbod Jahandar, Étienne Artigau, Diana Valencia, Neil J. Cook, Eder Martioli, Thomas Vandal, Jean-François Donati, Ryan Cloutier, Norio Narita, Akihiko Fukui, Teruyuki Hirano, François Bouchy, Nicolas B. Cowan, Erica J. Gonzales, David R. Ciardi, Keivan G. Stassun, Luc Arnold, Björn Benneke, Isabelle Boisse, Xavier Bonfils, Andrés Carmona, Pía Cortés-Zuleta, Xavier Delfosse, Thierry Forveille, Pascal Fouqué, João Gomes da Silva, Jon M. Jenkins, Flavien Kiefer, Ágnes Kóspál, David Lafrenière, Jorge H. C. Martins, Claire Moutou, J.-D. do Nascimento Jr., Merwan Ould-Elhkim, Stefan Pelletier, Joseph D. Twicken, Luke G. Bouma, Scott Cartwright, Antoine Darveau-Bernier, Konstantin Grankin, Masahiro Ikoma, Taiki Kagetani, Kiyoe Kawauchi, Takanori Kodama, Takayuki Kotani, David W. Latham, Kristen Menou, George Ricker, Sara Seager, Motohide Tamura, Roland Vanderspek and Noriharu Watanabe, 12 August 2022, The Astronomical Journal.DOI: 10.3847/ 1538-3881/ ac7cea.
The post was released on August 12, 2022, in The Astronomical Journal. In addition to Charles Cadieux, René Doyon, Étienne Artigau, Neil Cook, Farbod Jahandar and Thomas Vandal at the Université de Montréals iREx, the research team consists of Nicolas B. Cowan (iREx, MSI, McGill, Canada); Björn Benneke, Stefan Pelletier and Antoine Darveau-Bernier (iREx, UdeM, Canada); Ryan Cloutier, former member of iREx (Harvard, U.S.); and co-authors from University of Toronto, France, Brazil, the United States, Japan, Spain, Switzerland, Portugal, Hungary, Germany, and Crimea.

Artistic performance of the exoplanet TOI-1452 b, a small world that might be totally covered in a deep ocean. Credit: Benoit Gougeon, Université de Montréal
With the assistance of instruments designed partly in Canada, a group of astronomers has discovered an exoplanet that might be totally covered in water.
A global team of scientists has announced the discovery of TOI-1452 b, an exoplanet orbiting one of two little stars in a binary system located in the Draco constellation about 100 light-years from Earth. The researchers were led by Charles Cadieux, a Ph.D. student at the Université de Montréal and member of the Institute for Research on Exoplanets (iREx).
With a size and mass somewhat higher than that of Earth, the exoplanet is situated at a range from its star where its temperature would be neither too cold nor too hot for liquid water to exist on its surface. The astronomers think it might be an “ocean planet,” a world totally covered by a thick layer of water. This would make it similar to a few of the moons of Jupiter and Saturn.