Exploring the vast expanse of the cosmos has yielded fascinating discoveries, particularly in the field of exoplanet research. Exoplanets are planets that orbit stars outside our solar system, showcasing a diverse range of sizes, compositions, and orbital patterns. 

The astronomical unit (AU) is an essential measure in this field, representing the average distance between Earth and the Sun—approximately 93 million miles or 150 million kilometers. This unit helps scientists convey the vast distances between exoplanets and their host stars more intuitively.

These exoplanet discoveries are made possible through various observation methods. The radial velocity method detects shifts in starlight caused by gravitational pulls, creating a “wobble” effect, while the transit method identifies the slight dimming of a star’s light as a planet crosses in front of it. 

Direct imaging captures actual visual evidence of a planet by using specialized techniques to block out the star’s light, and missions like NASA’s Kepler and TESS (Transiting Exoplanet Survey Satellite) have been pivotal in the field, cataloging thousands of exoplanets.

The following sections delve into ten intriguing exoplanet discoveries, highlighting their unique characteristics, distances from their stars in AU, and how they challenge our understanding of planetary formation and survival. 

From massive gas giants like WASP-49 b to potentially habitable super-Earths such as TOI-1452 b, each planet contributes to our growing knowledge about the universe and its countless solar systems.

New Exoplanets

1. HD 36384 b 

Discovered in 2023, this gas giant exoplanet with a mass of 6.6 Jupiter orbits a K-type star; taking 490 days to complete one orbit.

This planet was discovered through the radial velocity method, which detects the “wobble” in distant stars caused by the gravitational pull of orbiting planets. It orbits a star nearly 40 times the size of our Sun.

2. TOI-198 b

TOI-198 b is a potentially rocky super-Earth that orbits along the inner edge of the habitable zone around its host star, an M dwarf. The planet was identified using the transit method, which detects exoplanets by observing the slight dimming in starlight as they pass in front of their stars during orbit.

TOI-198 b, officially announced in 2023, has a mass approximately 2.67 times that of Earth. Its orbit takes 10.2 days to complete!

3. TOI-4860 b 

TOI-4860 b is a gas giant exoplanet, classified as a “hot Jupiter” due to its size and close orbit around an M dwarf star. 

Discovered through the transit method, this exoplanet completes an orbit every 1.52 days, indicating its close proximity to its star. While gas giants near their stars are uncommon for Sun-like stars, it is even more unusual to find one orbiting so close to an M dwarf, as is the case here.

TOI-4860 b has a mass of approximately 0.67 that of Jupiter. It orbits its M-type star at a distance of 0.01845 AU, taking just 1.5 days to complete each orbit. This exoplanet’s discovery was announced in 2023.

4. MWC 758 c 

MWC 758 c is a massive protoplanet orbiting a young star that still retains its protoplanetary disk—a rotating structure of gas and dust that often surrounds young stars. This planet was discovered through direct imaging, and it has been observed carving spiral arms into its star’s protoplanetary disk.

MWC 758 c is one of the earliest exoplanets found in a system where the star maintains its protoplanetary disk. This unknown-type exoplanet orbits an A-type star at an impressive distance of 100 AU, taking roughly 817 years to complete a single orbit. Its discovery was officially announced in 2023.

5. Kepler-385 b

Kepler-385 b is a super-Earth exoplanet orbiting an F-type star. With a mass of approximately 12.8 times that of Earth, it completes an orbit around its star every 10 days at a distance of 0.097 AU. This exoplanet, the third known planet in the Kepler-385 system, was discovered in 2014.

6. WASP-49 b

WASP-49 b is a gas giant exoplanet with a composition primarily of hydrogen and helium, similar to its G-type star, along with trace amounts of sodium. 

The planet, which has a mass of about 0.37 times that of Jupiter, orbits very closely to its host star, completing a full orbit in only 2.8 days at a distance of 0.0379 AU. Its discovery, announced in 2012, made it a notable example of a “hot Jupiter,” a type of gas giant that experiences intense radiation from its close proximity star.

7. 8 Ursae Minoris b

Orbiting a star approximately 530 light-years away, 8 Ursae Minoris b remains in a surprisingly stable orbit despite the fact that its host, a red giant star, has expanded significantly. 

Astronomers anticipated that this star’s expansion would have consumed nearby planets, yet this gas giant exoplanet, which has a mass of about 1.31 Jupiters, maintains a near-circular orbit 0.49 AU from its star. It completes each orbit in 93.4 days. 

This intriguing survival story, based on measurements from NASA’s TESS, offers new insight into planetary resilience and the complexities of star-planet interactions. The planet’s discovery was made in 2015.

8. Kepler-1658 b

Kepler-1658 b is a hot Jupiter with a dynamic and challenging future, spiraling ever closer to its F-type host star. This gas giant, which has a mass nearly six times that of Jupiter, completes its orbit in 3.8 days at a distance of 0.0544 AU. 

As the first candidate identified by NASA’s Kepler Space Telescope in 2009, Kepler-1658 b holds a unique place in exoplanet discovery history. Despite its relatively large size, scientists expect it to collide with its star within 3 million years due to gravitational forces. Its official confirmation came in 2019.

9. TOI-1452 b

TOI-1452 b, a super-Earth exoplanet, orbits an M-type red dwarf about 100 light-years from Earth. With a mass of 4.82 times that of Earth, it takes roughly 11.1 days to orbit its star at a distance of 0.061 AU. 

Discovered in 2022 by a team led by the University of Montreal and with assistance from NASA’s TESS, TOI-1452 b is speculated to be a “water world,” potentially having liquid water on its surface. Interestingly, this planet’s host is part of a binary star system with another red dwarf orbiting in a 1,400-year cycle.

10. TOI-674 b

TOI-674 b, a Neptune-like exoplanet, orbits a cool M-type red dwarf star located roughly 150 light-years away. Its mass is estimated to be around 23.6 Earth masses, and it completes an orbit every 2 days at a distance of 0.025 AU. 

Discovered in 2021, TOI-674 b is among the few exoplanets known to have detectable water vapor in its atmosphere, making it an appealing candidate for further atmospheric analysis with tools like the James Webb Space Telescope. 

Its relatively close distance and the favorable size of its host star allow for detailed study, which may reveal more about its atmospheric composition and climate dynamics.

The continuous discovery of exoplanets has not only broadened our understanding of distant solar systems but has also redefined what we consider possible in terms of planetary formation and behavior. Each planet provides a piece of the larger puzzle, demonstrating that the conditions for planets and their interactions with host stars are more diverse than previously imagined. 

From gas giants like Kepler-1658 b, which teeters on a collision course with its star, to the mysterious protoplanet MWC 758 c, which influences the structure of its star’s protoplanetary disk, these celestial bodies exhibit surprising characteristics that challenge our expectations.

Advances in telescope technology and observation methods, such as the James Webb Space Telescope, promise to deepen our exploration by revealing detailed atmospheric compositions and possible signs of habitability. TOI-674 b is already an exciting candidate for such study, as its atmosphere is known to contain water vapor. The intriguing super-Earth TOI-1452 b, possibly a “water world,” hints at the potential for conditions favorable to life beyond Earth.

Each discovery propels our quest for knowledge, reminding us of the boundless variety of planetary systems in the cosmos. As scientists continue to uncover the secrets of these distant worlds, we come closer to answering fundamental questions about the origins of planets and the potential for life elsewhere in the universe. The future of exoplanet research is as vast and promising as the space it seeks to understand.