.png) The planetary system V1298 Tauri Credit: Exoplanet Exploration Program and the Jet Propulsion Laboratory for NASA’s Astrophysics Division | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 04 05 19.59121 |
| Declination | +20° 09′ 25.5635″ |
| Apparent magnitude (V) | 10.31 - 10.43 |
| Characteristics | |
| Spectral type | K0-K1.5 |
| Variable type | Irregular |
| Astrometry | |
| Proper motion (μ) | RA: 5.228 ± 0.131 mas/yr Dec.: -16.077 ± 0.048 mas/yr |
| Parallax (π) | 9.2139 ± 0.0593 mas |
| Distance | 354 ± 2 ly (108.5 ± 0.7 pc) |
| Details | |
| Mass | 1.095+0.049 −0.047 M☉ |
| Radius | 1.33+0.04 −0.03 R☉ |
| Luminosity | 0.934 ± 0.044 L☉ |
| Temperature | 4970 ± 120 K |
| Rotation | 2.97+0.03 −0.04 d |
| Age | 23 ± 4 Myr |
| Other designations | |
| K2-309, 2MASS J04051959+2009256, BD+19 656, EPIC 210818897, RX J0405.3+2009, 1SWASP J040519.59+200925.5 | |
| Database references | |
| SIMBAD | data |
V1298 Tauri is a young (23±4 Myr) weakly-lined T Tauri star that is part of the Taurus-Auriga association in the Taurus Molecular Cloud. Alternatively it is part of a proposed moving group, called Group 29 (or 93 Tau group) that is slightly older. The system has four transiting exoplanets, discovered with the Kepler space telescope in the K2 mission. One of the planets was discovered in August 2019 and the other three were discovered in November 2019 by the same team.
Stellar characteristics
V1298 Tauri has a spectral type of K0 - K1.5 and it has a mass of about 1.1 M☉. The star appears in x-rays from ROSAT data and it does show strong lithium absorption lines, both signatures of youth and therefore it was a proposed member of Taurus-Auriga. On the other hand it does not show signs of accretion and it lacks infrared excess. Instead it shows H-alpha in absorption.
The brightness of V1298 Tauri varies in an unpredictable way between a maximum visual magnitude of 10.31 and a minimum of 10.54. The light curve of the star shows quasi-periodic variability that was interpreted as stellar rotation and starspots. The light curve also showed several flares.
Based on Gaia DR2 data this star is part of a co-moving pair, together with HD 284154. The star is included in an analysis of the 93 Tau group, which finds an age of 35 ±5 Myrs.
Planetary system
V1298 Tauri has four confirmed planets of which planets c, d and b are near a 1:2:3 resonance (with periods of 8.25, 12.40 and 24.14 days). Planet e only shows a single transit in the K2 light curve and has a period larger than 36 days. Planet e might be in a low-order resonance (of 2:3, 3:5, 1:2, or 1:3) with planet b. The system is very young and might be a precursor of a compact multiplanet system. The 2:3 resonance suggests that some close-in planets may either form in resonances or evolve into them on timescales of less than 10 Myr. The planets in the system have a size between Neptune and Saturn. Only planet b has a size similar to Jupiter.
Models predict that the planets have a minimum core mass of 5 ME and are surrounded by a thick envelope that make up 20% of their mass. The total mass of planet c and d was predicted to be 2 - 28 ME and the total mass of planet d and b was predicted to be 9 - 120 ME. In a follow-up paper the mass of V1298 Tauri b was constrained to <2.2 MJ. The planet c was suspected to be shedding mass due to intense irradiation by the host star, but hydrogen tail existence was refuted by 2021.
Orbits of the planets b and c are nearly coplanar and planet c is not inclined to the equatorial plane of the star, misalignment equals to 2
−4 degrees.
Planet b was observed with Hubble WFC3 and a transmission spectrum was produced. This observation found a clear primordial atmosphere and water vapor absorption. The mass was constrained from this observation to less than 23 earth-masses, making this planet one of the lowest density planet observed. The team retrieved a low metallicity for the atmosphere, challenging formation mechanisms. The planet will likely evolve into a sub-Neptune in the future. Comparison between the transmission spectrum of planet b and a newly obtained WFC3 transmission spectrum for planet c found that planet b has a large, haze-free envelope. For planet c hazes could not be ruled out. The masses were constrained for planet b to below 20 earth masses and for planet c to 17+13
−6 earth masses. An ongoing transit-timing variation study suggest that both planet b and c are in the mass range of super-Earth to sub-Neptune planets and will evolve into these types of planet.
Planet e could be a planet with a water-rich core and an substantial hydrogen envelope. Planet e was possibly detected by Kepler, TESS and CHEOPS in three transits with an orbital period of around 45 days. The transits have different depths, lengths and maybe has TTVs of a few hours. Alternatively CHEOPS could have detected a fifth planet.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| c | 17+13 −6 M🜨 |
0.0825 ± 0.0013 | 8.24958 ± 0.00072 | <0.43 | 88.49+0.92 −0.72° |
0.499+0.032 −0.029 RJ |
| d | <41 M🜨 | 0.1083 ± 0.0017 | 12.4032 ± 0.0015 | <0.21 | 89.04+0.65 −0.73° |
0.572+0.040 −0.035 RJ |
| b | <20 M🜨 | 0.1688 ± 0.0026 | 24.1396 ± 0.0018 | <0.29 | 89.00+0.46 −0.24° |
0.916+0.052 −0.047 RJ |
| e | 0.66 ± 0.26 MJ | 0.308+0.182 −0.066 |
50.29±6.62 | <0.57 | 89.40+0.26 −0.18° |
0.89±0.04 RJ |
See also
- List of nearby stellar associations and moving groups
- List of exoplanets discovered in 2019
- Kepler-223 - the first confirmed system with four exoplanets in resonance
- K2-138 - a system with five exoplanets in a 3:2 resonance chain
- HD 110067 - a system with seven planets in orbital resonance
References
- ^ Gaia Collaboration (2018-08-01). "Gaia Data Release 2 - Summary of the contents and survey properties". Astronomy & Astrophysics. 616: A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. ISSN 0004-6361. S2CID 49211658.
- ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
- ^ David, Trevor J.; Cody, Ann Marie; Hedges, Christina L.; Mamajek, Eric E.; Hillenbrand, Lynne A.; Ciardi, David R.; Beichman, Charles A.; Petigura, Erik A.; Fulton, Benjamin J.; Isaacson, Howard T.; Howard, Andrew W. (August 2019). "A Warm Jupiter-sized Planet Transiting the Pre-main-sequence Star V1298 Tau". The Astronomical Journal. 158 (2): 79. arXiv:1902.09670. Bibcode:2019AJ....158...79D. doi:10.3847/1538-3881/ab290f. ISSN 0004-6256. S2CID 119003936.
- ^ Feinstein, Adina D.; David, Trevor J.; Montet, Benjamin T.; Foreman-Mackey, Daniel; Livingston, John H.; Mann, Andrew W. (2022). "V1298 Tau with TESS: Updated Ephemerides, Radii, and Period Constraints from a Second Transit of V1298 Tau E". The Astrophysical Journal Letters. 925 (1): L2. arXiv:2111.08660. Bibcode:2022ApJ...925L...2F. doi:10.3847/2041-8213/ac4745. S2CID 244130016.
- ^ David, Trevor J.; Petigura, Erik A.; Luger, Rodrigo; Foreman-Mackey, Daniel; Livingston, John H.; Mamajek, Eric E.; Hillenbrand, Lynne A. (2019-10-29). "Four Newborn Planets Transiting the Young Solar Analog V1298 Tau". The Astrophysical Journal. 885 (1): L12. arXiv:1910.04563. Bibcode:2019ApJ...885L..12D. doi:10.3847/2041-8213/ab4c99. ISSN 2041-8213. S2CID 204008446.
- ^ Oh, Semyeong; Price-Whelan, Adrian M.; Hogg, David W.; Morton, Timothy D.; Spergel, David N. (June 2017). "Comoving Stars in Gaia DR1: An Abundance of Very Wide Separation Comoving Pairs". The Astronomical Journal. 153 (6): 257. arXiv:1612.02440. Bibcode:2017AJ....153..257O. doi:10.3847/1538-3881/aa6ffd. ISSN 0004-6256. S2CID 119351439.
- Luhman, K. L. (December 2018). "The Stellar Membership of the Taurus Star-forming Region". The Astronomical Journal. 156 (6): 271. arXiv:1811.01359. Bibcode:2018AJ....156..271L. doi:10.3847/1538-3881/aae831. ISSN 0004-6256. S2CID 119471553.
- ^ Luhman, K. L. (2023-02-01). "A Census of the Taurus Star-forming Region and Neighboring Associations with Gaia". The Astronomical Journal. 165 (2): 37. arXiv:2211.09785. Bibcode:2023AJ....165...37L. doi:10.3847/1538-3881/ac9da3. ISSN 0004-6256.
- ^ Beichman, Charles; Hirano, Teruyuki; David, Trevor J.; Kotani, Takayuki; Hillenbrand, Lynne A.; Vasisht, Gautam; Ciardi, David R.; Harakawa, Hiroki; Kudo, Tomoyuki; Omiya, Masashi; Kuzuhara, Masayuki (June 2019). "A Mass Limit for the Young Transiting Planet V1298 Tau b". Research Notes of the AAS. 3 (6): 89. Bibcode:2019RNAAS...3...89B. doi:10.3847/2515-5172/ab2c9d. ISSN 2515-5172. S2CID 198445373.
- Schlawin, Everett; Ilyin, Ilya; Feinstein, Adina D.; Bean, Jacob; Huang, Chenliang; Gao, Peter; Strassmeier, Klaus; Poppenhaeger, Katja (2021), "H-Alpha Variability of V1298 Tau c", Research Notes of the American Astronomical Society, 5 (8): 195, arXiv:2108.08851, Bibcode:2021RNAAS...5..195S, doi:10.3847/2515-5172/ac1f2f, S2CID 237250293
- Gaidos, E.; Hirano, T.; Beichman, C.; Livingston, J.; Harakawa, H.; Hodapp, K. W.; Ishizuka, M.; Jacobson, S.; Konishi, M.; Kotani, T.; Kudo, T.; Kurokawa, T.; Kuzuhara, M.; Nishikawa, J.; Omiya, M.; Serizawa, T.; Tamura, M.; Ueda, A.; Vievard, S. (2022), "Zodiacal exoplanets in time – XIII. Planet orbits and atmospheres in the V1298 Tau system, a keystone in studies of early planetary evolution", Monthly Notices of the Royal Astronomical Society, 509 (2): 2969–2978, arXiv:2110.10689, doi:10.1093/mnras/stab3107
- Barat, Saugata; Désert, Jean-Michel; Vazan, Allona; Baeyens, Robin; Line, Michael R.; Fortney, Jonathan J.; David, Trevor J.; Livingston, John H.; Jacobs, Bob; Panwar, Vatsal; Shivkumar, Hinna; Todorov, Kamen O.; Pino, Lorenzo; Mraz, Georgia; Petigura, Erik A. (2024-07-01). "The metal-poor atmosphere of a potential sub-Neptune progenitor". Nature Astronomy. 8 (7): 899–908. arXiv:2312.16924. Bibcode:2024NatAs...8..899B. doi:10.1038/s41550-024-02257-0. ISSN 2397-3366.
- ^ Barat, Saugata; Désert, Jean-Michel; Goyal, Jayesh M.; Vazan, Allona; Kawashima, Yui; Fortney, Jonathan J.; Bean, Jacob L.; Line, Michael R.; Panwar, Vatsal (2024-07-01), First Comparative Exoplanetology Within a Transiting Multi-planet System: Comparing the atmospheres of V1298 Tau b and c, arXiv:2407.14995, retrieved 2024-10-16
- ^ Sikora, James; Rowe, Jason; Barat, Saugata; Bean, Jacob L.; Brady, Madison; Désert, Jean-Michel; Feinstein, Adina D.; Gilbert, Emily A.; Henry, Gregory; Kasper, David; Lizotte, Déreck-Alexandre; Matesic, Michael R. B.; Panwar, Vatsal; Seifahrt, Andreas; Shivkumar, Hinna (2023-06-01). "Updated Planetary Mass Constraints of the Young V1298 Tau System Using MAROON-X". The Astronomical Journal. 165 (6): 250. arXiv:2304.00797. Bibcode:2023AJ....165..250S. doi:10.3847/1538-3881/acc865. ISSN 0004-6256.
- Damasso, M.; Scandariato, G.; Nascimbeni, V.; Nardiello, D.; Mancini, L.; Marino, G.; Bruno, G.; Brandeker, A.; Leto, G.; Marzari, F.; Lanza, A. F.; Benatti, S.; Desidera, S.; Béjar, V. J. S.; Biagini, A. (2023-12-01). "Photometric follow-up of the 20 Myr old multi-planet host star V1298 Tau with CHEOPS and ground-based telescopes". Astronomy and Astrophysics. 680: A8. arXiv:2309.14131. Bibcode:2023A&A...680A...8D. doi:10.1051/0004-6361/202346840. ISSN 0004-6361.
- ^ Feinstein, Adina D.; David, Trevor J.; Montet, Benjamin T.; Foreman-Mackey, Daniel; Livingston, John H.; Mann, Andrew W. (2022), "V1298 Tau with TESS: Updated Ephemerides, Radii, and Period Constraints from a Second Transit of V1298 Tau E", The Astrophysical Journal Letters, 925 (1): L2, arXiv:2111.08660, Bibcode:2022ApJ...925L...2F, doi:10.3847/2041-8213/ac4745, S2CID 244130016
