18 Vulpeculae

Star in the constellation Vulpecula 18 Vulpeculae 250px A light curve for 18 Vulpeculae, plotted from TESS data, J2000.0 Vulpecula 20 10 33.53707 +26 54 15.0033 5.51 A3III or A3V 0.087 0.003 δ Sct, EL −11.70 0.11 18.785 0.164 12.694 0.172 6.6678 0.1098 −0.05 9.314077 0.000039 days 0.0116 0.0019 2454875.09 0.25 HJD 319.4 0.97 78.33 0.13 82.80 0.29 18 Vul A 2.4 3.5 0.3 3.73 0.07 8300 300 18 Vul B 2.2 2.4 0.2 +26 3815 191747 99404 7711 88295 18+Vulpeculae 18 Vulpeculae is a binary star system in the northern constellation of Vulpecula, located about 489 light years away from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.51. The system is moving closer to the Earth with a heliocentric radial velocity of −11.7 km/s. This is a double-lined spectroscopic binary system with an orbital period of 9.3 days and a small eccentricity of 0.0116. It is a detached binary with a semimajor axis of 31.7 ± 0.1 solar radius AU out on. The system contains a Delta Scuti variable, but the temperature places it to the blue (hotter) side of the δ Scuti instability strip. The AAVSO classifies it as a rotating ellipsoidal variable. The combined stellar classification of this system remains unclear, with classes of A3 III, A1 IV, A3 V, and A2 IV being given. The ultraviolet spectrum matches an A3 dwarf star. It shows no spectral peculiarities. References MAST: Barbara A. Mikulski Archive for Space Telescopes https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html Space Telescope Science Institute 27 August 2024 1836459472402822016 18 Vulpeculae 2018-11-18 18 Vul https://www.aavso.org/vsx/index.php?view=detail.top&oid=63465 The International Variable Star Index AAVSO 17 September 2024 New Precision Orbits of Bright Double-lined Spectroscopic Binaries. VIII. HR 1528, HR 6993, 2 Sagittae, and 18 Vulpeculae 1 Fekel Francis C. Tomkin Jocelyn Williamson Michael H. The Astronomical Journal 146 5 129 2013 2013AJ....146..129F 10.1088/0004-6256/146/5/129 2152/34407 121155872 free Liakos Alexios Niarchos Panagiotis Catalogue and properties of δ Scuti stars in binaries Monthly Notices of the Royal Astronomical Society 465 1 1181 2017 2017MNRAS.465.1181L 1611.00200 10.1093/mnras/stw2756 free 119284575 XHIP: An extended hipparcos compilation Anderson E. Francis Ch. Astronomy Letters 1108.4971 38 5 331 2012 2012AstL...38..331A 10.1134/S1063773712050015 119257644 External links 20 10 33.5 + 26 54 15 419.76277 Category:A-type giants Category:A-type main-sequence stars Category:Delta Scuti variables Category:Rotating ellipsoidal variables Category:Spectroscopic binaries Category:Vulpecula Category:Durchmusterung objects Vulpeculae, 18 191747 099404 7711 Category:A3 stars