List of terrestrial exoplanet candidates for atmosphere detection

The rocky exoplanets are thought to be abundant in the Milky Way, however their existence of atmosphere and their atmospheric composition are generally unknown. ^[1] The existence of a stable atmosphere depends on several factors including total amount of radiation receive (which is related to the spectral type of host star), the surface gravity (related to mass and radius) and the orbital period. ^[2]

As of 2024, 55 Cancri e is the first and the only terrestrial exoplanet with verified atmospheric detection. Its atmosphere might have been re-generated by the magma ocean and is composed of either carbon monoxide (CO) or carbon dioxide (CO₂). ^[3]

Table

To be included in the following list, an exoplanet must:

• Be terrestrial or nearly terrestrial
• Transit the host star from the Earth's view
• Have been studied with the transmission spectroscopy or secondary eclipse and have published claim(s) of atmospheric detection, whether confirmed or not.

Note that mass values prefixed with "~" have not been measured, but are estimated from the mass-radius relationship.

Row colors key

Solar system planet for reference

Solar system moon for reference

Exoplanet with confirmed atmosphere detection

Exoplanet with unconfirmed atmosphere detection

Planet	Host	Spectral type	Mass (M⊕)	Radius (R⊕)	Existence of atmosphere	Composition of atmosphere	Period (days)	Distance (ly)	Refs/notes
Earth (reported for reference)	Sun	G2V	1.00	1.00	Confirmed	78.08% nitrogen, 20.95% oxygen, 0.93% argon, water vapour and other trace gases	365.25	0	[4]
Venus (reported for reference)	Sun	G2V	0.815	0.950	Confirmed	96.5% carbon dioxide, 3.5% nitrogen, sulfur dioxide and other trace gases	244.26	~0	[5]
Mars (reported for reference)	Sun	G2V	0.107	0.533	Confirmed	95.97% carbon dioxide, 1.93% argon, 1.89% nitrogen, oxygen and other trace gases	686.98	~0	[6]
Titan (reported for reference)	Saturn	–	0.0225	0.404	Confirmed	(for the troposphere) 97% nitrogen, 2.7±0.1% methane, 0.1–0.2% hydrogen	15.945 (sidereal)	~0	[7]
LTT 1445 Ab	LTT 1445 A	M2.5V	2.73	1.34	Unconfirmed	Probably hydrogen cyanide	5.36	22.4	[8]
Gliese 486 b	Gliese 486	M3.5V	2.77	1.29	Unconfirmed	Probably water vapour	1.47	26.3	[9]
Gliese 357 b	Gliese 357	M2.5V	1.84	1.22	Unconfirmed	-	3.93	30.8	[10]
GJ 341 b	GJ 341	M1V	0.73	0.89	Unconfirmed	Likely water vapour or other small molecules	7.58	34.1	[11]
L 98-59 b	L 98-59	M3V	0.47	0.85	Confirmed	Likely sulfur dioxide	2.25	34.6	[12]
L 98-59 c	L 98-59	M3V	2.22	1.38	Unconfirmed	Likely carbon dioxide and water vapour	3.69	34.6	[13]
TRAPPIST-1b	TRAPPIST-1	M8V	1.37	1.12	Unconfirmed	Likely carbon dioxide	1.51	40.6	[14]
TRAPPIST-1c	TRAPPIST-1	M8V	1.31	1.10	Unconfirmed	Likely 99% oxygen + 1% carbon dioxide	2.42	40.6	[15]
LHS 475 b	LHS 475	M3.5V	~0.91	0.99	Unconfirmed	Probably carbon dioxide	2.03	40.7	[16]
55 Cancri e	55 Cancri A	K0IV-V	7.99	1.87	Confirmed	Carbon monoxide or carbon dioxide	0.736	41.0	[3]
LHS 1140 b	LHS 1140	M4.5V	5.60	1.73	Unconfirmed	Likely nitrogen	24.74	48.8	Located in the habitable zone [17]
LHS 1478 b	LHS 1478	M3.5V	2.33	1.20	Unconfirmed	Likely carbon dioxide and water vapour/ nitrogen	1.95	59.4	[18] [15]
HD 97658 b	HD 97658	K1V	7.81	2.25	Unconfirmed	Likely hydrogen, carbon monoxide and methane	9.49	70.3	[19]
L 168-9 b	L 168-9	M1V	4.07	1.63	Unconfirmed	Likely carbon dioxide	1.40	82.1	[20]

See also

• Extraterrestrial atmosphere
• List of nearest terrestrial exoplanet candidates
• Lists of planets

References

1. Wordsworth, Robin; Kreidberg, Laura (2022). "Atmospheres of Rocky Exoplanets". Annual Review of Astronomy and Astrophysics. 60: 159–201. arXiv: 2112.04663 . Bibcode:2022ARA&A..60..159W. doi:10.1146/annurev-astro-052920-125632.
2. Cutts, Elise (2025-03-12). "The Road Map to Alien Life Passes Through the 'Cosmic Shoreline'". Quanta Magazine. Retrieved 2025-06-15.
3. Hu, Renyu; Bello-Arufe, Aaron; Zhang, Michael; Paragas, Kimberly; Zilinskas, Mantas; van Buchem, Christiaan; Bess, Michael; Patel, Jayshil; Ito, Yuichi; Damiano, Mario; Scheucher, Markus; Oza, Apurva V.; Knutson, Heather A.; Miguel, Yamila; Dragomir, Diana (8 May 2024). "A secondary atmosphere on the rocky Exoplanet 55 Cancri e" . Nature . 630 (8017): 609–612. arXiv: 2405.04744 . Bibcode:2024Natur.630..609H. doi:10.1038/s41586-024-07432-x. ISSN   1476-4687. PMID   38718834.
4. Williams, David R. (15 November 2024). "Earth Fact Sheet". NASA/Goddard Space Flight Center. Archived from the original on 8 May 2013. Retrieved 30 December 2024.
5. Williams, David R. (25 November 2020). "Venus Fact Sheet". NASA Goddard Space Flight Center. Archived from the original on 11 May 2018. Retrieved 15 April 2021.
6. Williams, David (2018). "Mars Fact Sheet". NASA Goddard Space Flight Center. Archived from the original on 17 March 2020. Retrieved 22 March 2020.; Mean Anomaly (deg) 19.412 = (Mean Longitude (deg) 355.45332) – (Longitude of perihelion (deg) 336.04084) This article incorporates text from this source, which is in the public domain .
7. Coustenis & Taylor (2008), pp. 154–155. sfnp error: no target: CITEREFCoustenisTaylor2008 (help)
8. Bennett, Katherine A.; Sing, David K.; Stevenson, Kevin B.; Wakeford, Hannah R.; Rustamkulov, Zafar; Allen, Natalie H.; Lothringer, Joshua D.; MacDonald, Ryan J.; Mayne, Nathan J.; Fu, Guangwei (2025-02-01). "An HST Transmission Spectrum of the Closest M Dwarf Transiting Rocky Planet LTT 1445Ab". The Astronomical Journal. 169 (2): 111. arXiv: 2410.11054 . Bibcode:2025AJ....169..111B. doi: 10.3847/1538-3881/ad9dd1 . ISSN   0004-6256.
9. Moran, Sarah E.; Stevenson, Kevin B.; et al. (May 2023). "High Tide or Rip-Tide on the Cosmic Shoreline? A Water-Rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ 486b from JWST Observations". The Astrophysical Journal Letters . 948 (1): L11. arXiv: 2305.00868 . Bibcode:2023ApJ...948L..11M. doi: 10.3847/2041-8213/accb9c .
10. Taylor, Jake; Radica, Michael; Chatterjee, Richard D.; Hammond, Mark; Meier, Tobias; Aigrain, Suzanne; MacDonald, Ryan J.; Albert, Loic; Benneke, Björn; Coulombe, Louis-Philippe; Cowan, Nicolas B.; Dang, Lisa; Doyon, René; Flagg, Laura; Johnstone, Doug; Kaltenegger, Lisa; Lafrenière, David; Pelletier, Stefan; Piaulet-Ghorayeb, Caroline; Rowe, Jason F.; Roy, Pierre-Alexis (2025). "JWST NIRISS Transmission Spectroscopy of the Super-Earth GJ 357b, a Favourable Target for Atmospheric Retention". Monthly Notices of the Royal Astronomical Society. 540 (4): 3677. arXiv: 2505.24462 . Bibcode:2025MNRAS.540.3677T. doi: 10.1093/mnras/staf894 .
11. Kirk, James; Stevenson, Kevin B.; Fu, Guangwei; Lustig-Yaeger, Jacob; Moran, Sarah E.; Peacock, Sarah; Alam, Munazza K.; Batalha, Natasha E.; Bennett, Katherine A.; Gonzalez-Quiles, Junellie; López-Morales, Mercedes; Lothringer, Joshua D.; MacDonald, Ryan J.; May, E. M.; Mayorga, L. C.; Rustamkulov, Zafar; Sing, David K.; Sotzen, Kristin S.; Valenti, Jeff A.; Wakeford, Hannah R. (2024). "JWST/NIRCam Transmission Spectroscopy of the Nearby Sub-Earth GJ 341b". The Astronomical Journal. 167 (3): 90. arXiv: 2401.06043 . Bibcode:2024AJ....167...90K. doi: 10.3847/1538-3881/ad19df .
12. Bello-Arufe, Aaron; Damiano, Mario; et al. (January 2025). "Evidence for a volcanic atmosphere on the sub-Earth L98-59b". The Astrophysical Journal Letters . 980 (2): L26. arXiv: 2501.18680 . Bibcode:2025ApJ...980L..26B. doi: 10.3847/2041-8213/adaf22 .
13. Barclay, Thomas; Sheppard, Kyle B.; Latouf, Natasha; Mandell, Avi M.; Quintana, Elisa V.; Gilbert, Emily A.; Liuzzi, Giuliano; Villanueva, Geronimo L.; Arney, Giada; Brande, Jonathan; Colón, Knicole D.; Covone, Giovanni; Crossfield, Ian J. M.; Damiano, Mario; Domagal-Goldman, Shawn D.; Fauchez, Thomas J.; Fiscale, Stefano; Gallo, Francesco; Hedges, Christina L.; Hu, Renyu; Kite, Edwin S.; Koll, Daniel; Kopparapu, Ravi K.; Kostov, Veselin B.; Kreidberg, Laura; Lopez, Eric D.; Mang, James; Morley, Caroline V.; Mullally, Fergal; Mullally, Susan E. (2025), "The transmission spectrum of the potentially rocky planet L 98-59 c", The Astronomical Journal, 169 (5): 241, arXiv: 2301.10866 , Bibcode:2025AJ....169..241B, doi: 10.3847/1538-3881/ada5f6
14. Ducrot, Elsa; Lagage, Pierre-Olivier; Min, Michiel; Gillon, Michael; Bell, Taylor J.; Tremblin, Pascal; Greene, Thomas; Dyrek, Achrene; Bouwman, Jeroen; Waters, Rens; Gudel, Manuel; Henning, Thomas; Vandenbussche, Bart; Absil, Olivier; Barrado, David; Boccaletti, Anthony; Coulais, Alain; Deccin, Leen; Edwards, Billy; Gastaud, Rene; Glasse, Alistair; Kendrew, Sarah; Olofsson, Goran; Patapis, Polychronis; Pye, John; Rouan, Daniel; Whiteford, Niall; Argyriou, Ioannis; Cossou, Christopher; Glauser, Adrian M.; Krause, Oliver; Lahuis, Fred; Royer, Pierre; Scheithauer, Silvia; Colina, Luis; van Dishoeck, Ewine F.; Ostlin, Goran; Ray, Tom P.; Wright, Gillian (2024). "Combined analysis of the 12.8 and 15 μm JWST/MIRI eclipse observations of TRAPPIST-1 B". Nature Astronomy. 9 (3): 358–369. arXiv: 2412.11627 . doi:10.1038/s41550-024-02428-z.
15. Connors, Nicholas J.; Monaghan, Christopher; Benneke, Björn; Dang, Lisa (2 July 2025). "Uniform Reanalysis of JWST MIRI 15μm Exoplanet Eclipse Observations using Frame-Normalized Principal Component Analysis". The Astrophysical Journal. 989 (1): L11. arXiv: 2507.02052 . Bibcode:2025ApJ...989L..11C. doi: 10.3847/2041-8213/adee0d .
16. Lustig-Yaeger, J.; Fu, G.; et al. (January 2023). "A JWST transmission spectrum of the nearby Earth-sized exoplanet LHS 475 b". Nature Astronomy . 7 (11): 1317–1328. arXiv: 2301.04191 . Bibcode:2023NatAs...7.1317L. doi:10.1038/s41550-023-02064-z. S2CID   261439142.
17. "Habitable Zone Exoplanet LHS 1140b is Probably Snowball or Water World | Sci.News". Sci.News: Breaking Science News. 2024-07-09. Retrieved 2024-07-10.
18. August, P. C.; Buchhave, L. A.; Diamond-Lowe, H.; Mendonça, J. M.; Gressier, A.; Rathcke, A. D.; Allen, N. H.; Fortune, M.; Jones, K. D.; Meier Valdés, E. A.; Demory, B.-O.; Espinoza, N.; Fisher, C. E.; Gibson, N. P.; Heng, K.; Hoeijmakers, J.; Hooton, M. J.; Kitzmann, D.; Prinoth, B.; Eastman, J. D.; Barnes, R. (2025). "Hot Rocks Survey I: A possible shallow eclipse for LHS 1478 B". Astronomy & Astrophysics. 695: A171. arXiv: 2410.11048 . Bibcode:2025A&A...695A.171A. doi:10.1051/0004-6361/202452611.
19. Guo, Xueying; et al. (2020). "Updated Parameters and a New Transmission Spectrum of HD 97658b". The Astronomical Journal. 159 (5): 239. arXiv: 2004.03601 . Bibcode:2020AJ....159..239G. doi: 10.3847/1538-3881/ab8815 . S2CID   215415990.
20. Alam, Munazza K.; et al. (2025). "JWST COMPASS: The First Near- to Mid-infrared Transmission Spectrum of the Hot Super-Earth L 168-9 b". The Astronomical Journal. 169 (1) 15. arXiv: 2411.03154 . Bibcode: 2025AJ....169...15A . doi: 10.3847/1538-3881/ad8eb5 .