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CE Antliae

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CE Antliae

VLT and MIRI observations of the disk and planet candidate around CE Antliae[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Antlia
Right ascension 10h 42m 30.10s[2]
Declination −33° 40′ 16.2″[2]
Apparent magnitude (V) 10.91±0.07[3]
Characteristics
Evolutionary stage T Tauri star[4]
Spectral type M1[4]
Variable type rotational variable,[5] flare star[6]
Astrometry
Radial velocity (Rv)10.81±4.41[2] km/s
Proper motion (μ) RA: −118.751(23) mas/yr[2]
Dec.: −19.648(26) mas/yr[2]
Parallax (π)29.3277±0.0273 mas[2]
Distance111.2 ± 0.1 ly
(34.10 ± 0.03 pc)
Absolute magnitude (MV)+9.0[7]
Details
Mass0.46±0.09[8] M
Radius0.92±0.12[8] R
Luminosity0.115±0.019[8] L
Surface gravity (log g)4.18±0.17[8] cgs
Temperature3509±116[8] K
Rotation4.92[5] days
Rotational velocity (v sin i)63.2[5] km/s
Age6.4±1.1[9] Myr
Other designations
TWA 7, CE Ant, TYC 7190-2111-1, ASAS J104230-3340.3, GSC 07190-02111, 2MASS J10423011-3340162, RX J104230.3-334014, TIC 54147487, WISE J104230.01-334016.4, Gaia DR2 5444751795151480320
Database references
SIMBADdata

CE Antliae (also called TWA 7) is a young low-mass star in the constellation of Antlia. It is surrounded by a debris disk and has one directly imaged planet candidate.[10]

A light curve for CE Antliae, plotted from TESS data.[11] The star's rotation period is marked in red.

TWA 7 was discovered in 1999 with a spectral type of M1 and as a member of the TW Hydrae association.[4] The detection of molecular hydrogen is interpreted as a weak sign of accretion of gas near the star.[12] A giant x-ray flare was detected on 2010-09-07 with MAXI/GSC on the ISS.[6]

Planetary system

[edit]
TWA 7 disk with Gemini South telescope

The disk was first imaged in scattered light in 1998 with Hubble NICMOS, but it needed a re-processing in 2016 to reveal the disk. The observation showed a pole-on dust ring with a radius of about 35 astronomical units.[13] An outer ring and a spiral arm originating from the main ring was tentatively detected with VLT/SPHERE in 2018. The modelling also showed evidence of an inner ring.[14] An additional observation with Hubble STIS showed three rings, two spirals and a clump.[15] In 2000 dust was detected around TWA 7 due to excess submillimeter radiation.[16] ALMA observations did however show that most emission come from a background galaxy. The disk was also detected with ALMA.[17] The disk has detected carbon monoxide (CO) gas from ALMA observations, which is likely generated by exocomets. It was the first detection of CO gas in a debris disk around an M-dwarf. This kind of detection is more common around more massive stars.[18]

In 2025 JWST MIRI observations showed a point source that could be a young sub-Jovian planet with a mass of 0.3 MJ (about 100 M🜨) and a temperature of around 320 Kelvin. The candidate can explain the main ring of the debris disk. It also does not fit the spectrum of a background star. It could be consistent with an intermediate-redshift star-forming galaxy, but the probability of such a galaxy appearing that close to TWA 7 is estimated to be 0.34%.[10] If confirmed as a planet, it would be the least massive directly imaged exoplanet.[10] The candidate is located in an underdensity in ring 2 that was noticed before. Opposite to the planet candidate is another underdensity, which could be created by orbital resonance. The mass of the candidate was previously predicted to be 2 Neptune masses (about 34 M🜨) before it was detected.[15][10]

This candidate planet was independently detected by observations taken with the NIRCam instrument aboard JWST. The observations strongly support a planetary nature for this object, finding a background galaxy to be unlikely. The planet's mass could be similar to Neptune's. A second point-like source was also detected, but it needs follow-up observations to determine its nature.[19]

The CE Antlae planetary system[15][10]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
Ring 1 24.49±0.04 AU
b (candidate) 0.3 MJ 52 550
Ring 2 52.38±0.12 AU
Ring 3 101+2
−3
AU

See also

[edit]
Other M dwarfs with debris disks

References

[edit]
  1. ^ "Webb captures evidence of a lightweight planet around TWA 7". esawebb.org. 25 June 2025. Retrieved 26 June 2025.
  2. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ^ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355. Bibcode:2000A&A...355L..27H.
  4. ^ a b c Webb, R. A.; Zuckerman, B.; Platais, I.; Patience, J.; White, R. J.; Schwartz, M. J.; McCarthy, C. (1999-02-01). "Discovery of Seven T Tauri Stars and a Brown Dwarf Candidatein the Nearby TW Hydrae Association". The Astrophysical Journal. 512 (1): L63 – L67. arXiv:astro-ph/9812189. Bibcode:1999ApJ...512L..63W. doi:10.1086/311856. ISSN 0004-637X.
  5. ^ a b c Yamashita, Mai; Itoh, Yoichi; Takagi, Yuhei (November 2024). "Chromospheric Mg I emission lines of pre-main-sequence stars". Astronomy & Astrophysics. 691: A304. arXiv:2410.03087. Bibcode:2024A&A...691A.304Y. doi:10.1051/0004-6361/202452025. ISSN 0004-6361.
  6. ^ a b Uzawa, Akiko; Tsuboi, Yohko; Morii, Mikio; Yamazaki, Kyohei; Kawai, Nobuyuki; Matsuoka, Masaru; Nakahira, Satoshi; Serino, Motoko; Matsumura, Takanori; Mihara, Tatehiro; Tomida, Hiroshi; Ueda, Yoshihiro; Sugizaki, Mutsumi; Ueno, Shiro; Daikyuji, Arata (2011-11-25). "A Large X-Ray Flare from a Single Weak-Lined T Tauri Star TWA-7 Detected with MAXI GSC". Publications of the Astronomical Society of Japan. 63 (sp3): S713 – S716. arXiv:1108.5897. Bibcode:2011PASJ...63S.713U. doi:10.1093/pasj/63.sp3.S713. ISSN 0004-6264.
  7. ^ Bell, Cameron P. M.; Mamajek, Eric E.; Naylor, Tim (2015). "A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood". Monthly Notices of the Royal Astronomical Society. 454 (1): 593. arXiv:1508.05955. Bibcode:2015MNRAS.454..593B. doi:10.1093/mnras/stv1981.
  8. ^ a b c d e Stassun, Keivan G.; Oelkers, Ryan J.; Paegert, Martin; Torres, Guillermo; Pepper, Joshua; Lee, Nathan De; Collins, Kevin; Latham, David W.; Muirhead, Philip S.; Chittidi, Jay; Rojas-Ayala, Bárbara; Fleming, Scott W.; Rose, Mark E.; Tenenbaum, Peter; Ting, Eric B. (2019-09-09). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. ISSN 0004-6256.
  9. ^ Binks, A. S.; Jeffries, R. D.; Wright, N. J. (2020). "A kinematically hot population of young stars in the solar neighbourhood". Monthly Notices of the Royal Astronomical Society. 494 (2): 2429. arXiv:2003.13369. Bibcode:2020MNRAS.494.2429B. doi:10.1093/mnras/staa909.
  10. ^ a b c d e Lagrange, A.-M.; Wilkinson, C.; Mâlin, M.; Boccaletti, A.; Perrot, C.; Matrà, L.; Combes, F.; Rouan, D.; Beust, H. (25 June 2025). "Evidence for a sub-Jovian planet in the young TWA 7 disk". Nature. arXiv:2502.15081. doi:10.1038/s41586-025-09150-4. PMID 40562924.
  11. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 24 February 2025.
  12. ^ Flagg, Laura; Johns-Krull, Christopher M.; France, Kevin; Herczeg, Gregory; Najita, Joan; Carpenter, John M.; Kenyon, Scott J. (2021-11-01). "Detection of H2 in the TWA 7 System: A Probable Circumstellar Origin". The Astrophysical Journal. 921 (1): 86. arXiv:2108.08327. Bibcode:2021ApJ...921...86F. doi:10.3847/1538-4357/ac1d4c. ISSN 0004-637X.
  13. ^ Choquet, Élodie; Perrin, Marshall D.; Chen, Christine H.; Soummer, Rémi; Pueyo, Laurent; Hagan, James B.; Gofas-Salas, Elena; Rajan, Abhijith; Golimowski, David A.; Hines, Dean C.; Schneider, Glenn; Mazoyer, Johan; Augereau, Jean-Charles; Debes, John; Stark, Christopher C.; Wolff, Schuyler; n'Diaye, Mamadou; Hsiao, Kevin (2016). "First Images of Debris Disks around TWA 7, TWA 25, HD 35650, and HD 377". The Astrophysical Journal. 817 (1): L2. arXiv:1512.02220. Bibcode:2016ApJ...817L...2C. doi:10.3847/2041-8205/817/1/L2.`
  14. ^ Olofsson, J.; van Holstein, R. G.; Boccaletti, A.; Janson, M.; Thébault, P.; Gratton, R.; Lazzoni, C.; Kral, Q.; Bayo, A.; Canovas, H.; Caceres, C.; Ginski, C.; Pinte, C.; Asensio-Torres, R.; Chauvin, G. (September 2018). "Resolving faint structures in the debris disk around TWA 7". Astronomy & Astrophysics. 617: A109. arXiv:1804.01929. Bibcode:2018A&A...617A.109O. doi:10.1051/0004-6361/201832583. ISSN 0004-6361.
  15. ^ a b c Ren 任, Bin 彬; Choquet, Élodie; Perrin, Marshall D.; Mawet, Dimitri; Chen, Christine H.; Milli, Julien; Debes, John H.; Rebollido, Isabel; Stark, Christopher C.; Hagan, J. Brendan; Hines, Dean C.; Millar-Blanchaer, Maxwell A.; Pueyo, Laurent; Roberge, Aki; Schneider, Glenn (2021-06-01). "A Layered Debris Disk around M Star TWA 7 in Scattered Light". The Astrophysical Journal. 914 (2): 95. arXiv:2105.09949. Bibcode:2021ApJ...914...95R. doi:10.3847/1538-4357/ac03b9. ISSN 0004-637X.
  16. ^ Webb, R. A.; Zuckerman, B.; Greaves, J. S.; Holland, W. S. (December 2000). "Large, cold dust grains orbiting stars in the TW Hydrae Association". American Astronomical Society, 197th AAS Meeting, Id.08.27. 32: 1410. Bibcode:2000AAS...197.0827W.
  17. ^ Bayo, A; Olofsson, J; Matrà, L; Beamín, J C; Gallardo, J; de Gregorio-Monsalvo, I; Booth, M; Zamora, C; Iglesias, D; Henning, Th; Schreiber, M R; Cáceres, C (July 2019). "Sub-millimetre non-contaminated detection of the disc around TWA 7 by ALMA". Monthly Notices of the Royal Astronomical Society. 486 (4): 5552–5557. arXiv:1806.09252. Bibcode:2019MNRAS.486.5552B. doi:10.1093/mnras/stz1133. ISSN 0035-8711.
  18. ^ Matrà, L.; Öberg, K. I.; Wilner, D. J.; Olofsson, J.; Bayo, A. (2019-02-14). "On the Ubiquity and Stellar Luminosity Dependence of Exocometary CO Gas: Detection around M Dwarf TWA 7". The Astronomical Journal. 157 (3): 117. arXiv:1901.05004. Bibcode:2019AJ....157..117M. doi:10.3847/1538-3881/aaff5b. ISSN 0004-6256.
  19. ^ Crotts, Katie A.; et al. (2025). "Follow-Up Exploration of the TWA 7 Planet-Disk System with JWST NIRCam". The Astrophysical Journal Letters. arXiv:2506.19932.