NSVS 14256825, also known as V1828 Aquilae, is an eclipsing binary system (of the Algol type) in the constellation of Aquila. The system comprises a subdwarf OB star and red dwarf star. The two stars orbit each other every 2.648976 hours.[1] Based on the stellar parallax of the system, observed by Gaia, the system is located approximately 2,700 light-years (840 parsecs) away.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 20h 20m 00.45867s[2] |
| Declination | +04° 37′ 56.5198″[2] |
| Apparent magnitude (V) | 13.2[3] |
| Characteristics | |
| Spectral type | sdOB / M V[3] |
| Astrometry | |
| Radial velocity (Rv) | 12.10 ± 1.5[4] km/s |
| Proper motion (μ) | RA: 8.063[2] mas/yr Dec.: 1.133[2] mas/yr |
| Parallax (π) | 1.1929 ± 0.0599 mas[2] |
| Distance | 2,700 ± 100 ly (840 ± 40 pc) |
| Orbit[1] | |
| Period (P) | 0.110374230 d |
| Inclination (i) | 82.5° |
| Periastron epoch (T) | 2454274.20874 JD |
| Details[3] | |
| Mass | 0.528 M☉ |
| Temperature | 42,000 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
In 2007, Patrick Wils et al. discovered that NSVS 14256825 is an eclipsing binary, by examining the Northern Sky Variability Survey (NSVS) data. They also classified it as an HW Virginis type star, a binary pair in which variability arises from one star reflecting the light of the other as they orbit each other.[6][7][8]
Nomenclature
editThe system is most commonly referred to using its designation from the NSVS, a survey of stars with apparent magnitudes between 8 and 15.5.[8] It also has a variable star designation, V1828 Aquilae.[5]
Eclipse timing variations
editNSVS 14256825 has been extremely well-studied using photometry,[9] but the resulting models often contradict each other, even with similar statistical significance,[10] or with data that are collected later.[9] Many studies have found that this system exhibits eclipse timing variations (ETVs) that are significant, cyclic[9] and not explainable by other stellar mechanisms such as the Applegate mechanism.[11] In 2012, it was found that the orbit of NSVS 14256825 was increasing at a rate of 12×10−12 days per orbit.[12]
Initially, in 2012 it was claimed that two giant planets were in orbit around the binary, with masses of 2.9 and 8.1 times the mass of Jupiter orbiting with periods of 3.5 and 6.9 years respectively.[1] Another paper claimed the existence of one planet with a mass 12 times that of Jupiter, in a 20-year orbit.[13] However, subsequent studies have come up with different results with masses up to 15 MJ[11] and periods down to 8.83 years.[14] Studies also do not agree on whether one substellar body can explain the ETVs, or whether additional companions are necessary, but further research is needed to obtain better coverage of data.[15]
See also
editReferences
edit- ^ a b c d Almeida, L. A.; Jablonski, F.; Tello, J.; Rodrigues, C. V. (2012). "A photometric and spectroscopic study of NSVS 14256825: the second sdOB+dM eclipsing binary". Monthly Notices of the Royal Astronomical Society. 423 (1): 478–485. arXiv:1203.1266. Bibcode:2012MNRAS.423..478A. doi:10.1111/j.1365-2966.2012.20891.x. S2CID 119177743.
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "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.
- ^ a b c "Notes on NSVS 1425 (AB) b". Extrasolar Planets Encyclopaedia. Retrieved 26 November 2016.
- ^ Kupfer, T.; Geier, S.; Heber, U.; Østensen, R. H.; Barlow, B. N.; Maxted, P. F. L.; Heuser, C.; Schaffenroth, V.; Gänsicke, B. T. (2015). "Hot subdwarf binaries from the MUCHFUSS project. Analysis of 12 new systems and a study of the short-period binary population". Astronomy and Astrophysics. 576: A44. arXiv:1501.03692. Bibcode:2015A&A...576A..44K. doi:10.1051/0004-6361/201425213. S2CID 53724563.
- ^ a b "NSVS 14256825". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-10-16.
- ^ Wils, Patrick; di Scala, Giorgio; Otero, Sebastian A. (October 2007). "NSVS 14256825: A New HW Vir Type System" (PDF). Information Bulletin on Variable Stars. 5800: 1–5. Retrieved 22 November 2024.
- ^ "V1828 Aql". The International Variable Star Index. AAVSO. Retrieved 22 November 2024.
- ^ a b Woźniak, P. R.; Vestrand, W. T.; Akerlof, C. W.; Balsano, R.; Bloch, J.; Casperson, D.; Fletcher, S.; Gisler, G.; Kehoe, R.; Kinemuchi, K.; Lee, B. C.; Marshall, S.; McGowan, K. E.; McKay, T. A.; Rykoff, E. S.; Smith, D. A.; Szymanski, J.; Wren, J. (2004). "Northern Sky Variability Survey: Public Data Release". The Astronomical Journal. 127 (4): 2436–2449. arXiv:astro-ph/0401217. Bibcode:2004AJ....127.2436W. doi:10.1086/382719. S2CID 2974543.
- ^ a b c Pulley, D.; Faillace, G.; Smith, D.; Watkins, A.; von Harrach, S. (2018). "The quest for stable circumbinary companions to post-common envelope SDB eclipsing binaries. Does the observational evidence support their existence?". Astronomy and Astrophysics. 611: 611. arXiv:1711.03749. Bibcode:2018A&A...611A..48P. doi:10.1051/0004-6361/201731125. S2CID 54997940.
- ^ Hinse, Tobias Cornelius; Lee, Jae Woo; Goździewski, Krzysztof; Horner, Jonathan; Wittenmyer, Robert A. (2014). "Revisiting the proposed circumbinary multiplanet system NSVS 14256825". Monthly Notices of the Royal Astronomical Society. 438 (1): 307. arXiv:1311.3021. Bibcode:2014MNRAS.438..307H. doi:10.1093/mnras/stt2183.
- ^ a b Nasiroglu, Ilham; Goździewski, Krzysztof; Słowikowska, Aga; Krzeszowski, Krzysztof; Żejmo, Michał; Zola, Staszek; Er, Huseyin; Ogłoza, Waldemar; Dróżdż, Marek; Koziel-Wierzbowska, Dorota; Debski, Bartlomiej; Karaman, Nazli (2017). "Is There a Circumbinary Planet around NSVS 14256825?". The Astronomical Journal. 153 (3): 137. arXiv:1701.05211. Bibcode:2017AJ....153..137N. doi:10.3847/1538-3881/aa5d10. S2CID 118936443.
- ^ Kilkenny, D.; Koen, C. (2012). "Detection of an increasing orbital period in the subdwarf B eclipsing system NSVS 14256825". Monthly Notices of the Royal Astronomical Society. 421 (4): 3238. Bibcode:2012MNRAS.421.3238K. doi:10.1111/j.1365-2966.2012.20547.x. hdl:10566/891.
- ^ Beuermann, K.; Breitenstein, P.; Debski, B.; Diese, J.; Dubovsky, P. A.; Dreizler, S.; Hessman, F. V.; Hornoch, K.; Husser, T. -O.; Pojmanski, G.; Wolf, M.; Woźniak, P. R.; Zasche, P.; Denk, B.; Langer, M.; Wagner, C.; Wahrenberg, D.; Bollmann, T.; Habermann, F. N.; Haustovich, N.; Lauser, M.; Liebing, F.; Niederstadt, F. (2012). "The quest for companions to post-common envelope binaries. II. NSVS14256825 and HS0705+6700". Astronomy and Astrophysics. 540: A8. arXiv:1202.5990. Bibcode:2012A&A...540A...8B. doi:10.1051/0004-6361/201118105. S2CID 119267859.
- ^ Zhu, Li-Ying; Qian, Sheng-Bang; Fernández Lajús, Eduardo; Wang, Zhi-Hua; Li, Lin-Jia; -J, Li L. (2019). "A close-in substellar object orbiting the sdOB-type eclipsing-binary system NSVS 14256825". Research in Astronomy and Astrophysics. 19 (9): 134. arXiv:1904.11664. Bibcode:2019RAA....19..134Z. doi:10.1088/1674-4527/19/9/134. S2CID 135471537.
- ^ Wolf, M.; Kučáková, H.; Zasche, P.; Hornoch, K.; Kára, J.; Merc, J.; Zejda, M. (2021). "Possible substellar companions in dwarf eclipsing binaries. SDSS J143547.87+373338.5, NSVS 7826147, and NSVS 14256825". Astronomy and Astrophysics. 647: 647. arXiv:2101.08475. Bibcode:2021A&A...647A..65W. doi:10.1051/0004-6361/202039851. S2CID 231662494.