The Saric ßic ßek howardite meteorite shower consisting of 343 documented stones occurred on September 2, 2015 in Turkey and is the first documented howardite fall. Cosmogenic isotopes show that Saric ßic ßek experienced a complex cosmic-ray exposure history, exposed during~12-14 Ma in a regolith near the surface of a parent asteroid, and that añ 1 m sized meteoroid was launched by an impact 22 AE 2 Ma ago to Earth (as did one-third of all HED meteorites). SIMS dating of zircon and baddeleyite yielded 4550.4 AE 2.5 Ma and 4553 AE 8.8 Ma crystallization ages for the basaltic magma clasts. The apatite U-Pb age of 4525 AE 17 Ma, K-Ar age of~3.9 Ga, and the U,Th-He ages of 1.8 AE 0.7 and 2.6 AE 0.3 Ga are interpreted to represent thermal metamorphic and impact-related resetting ages, respectively. Petrographic; geochemical; and O-, Cr-, and Ti-isotopic studies confirm that Saric ßic ßek belongs to the normal clan of HED meteorites. Petrographic observations and analysis of organic material indicate a small portion of carbonaceous chondrite material in the Saric ßic ßek regolith and organic contamination of the meteorite after a few days on soil. Video observations of the fall show an atmospheric entry at 17.3 AE 0.8 km s À1 from NW; fragmentations at 37, 33, 31, and 27 km altitude; and provide a pre-atmospheric orbit that is the first dynamical link between the normal HED meteorite clan and the inner Main Belt. Spectral data indicate the similarity of Saric ßic ßek with the Vesta asteroid family (V-class) spectra, a group of asteroids stretching to delivery resonances, which includes (4) Vesta. Dynamical modeling of meteoroid delivery to Earth shows that the complete disruption of ã 1 km sized Vesta family asteroid or a~10 km sized impact crater on Vesta is required to provide sufficient meteoroids ≤4 m in size to account for the influx of meteorites from this HED clan. The 16.7 km diameter Antionia impact crater on Vesta was formed on terrain of the same age as given by the 4 He retention age of Saric ßic ßek. Lunar scaling for crater production to crater counts of its ejecta blanket show it was formed~22 Ma ago.A field expedition to the area was conducted by the

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We present the results of our investigation of the geometrical and physical parameters of the W UMa-type binary V404 Peg from analysis of CCD (BVRI) light curves and radial velocity data. The photometric data were obtained during 2010 at Ankara University Observatory (AUO). Light and radial velocity observations were analyzed simultaneously by using the well-known Wilson-Devinney (2007 revision) code to obtain absolute and geometrical parameters. Our solution indicates that V404 Peg is an A-type overcontact binary with a mass ratio of q = 0.243 and an overcontact degree of f = 32.1 %. Combining our light curves with the radial velocity curves from Maciejewski & Ligeza (2004), we determined the absolute parameters of this system as follows: a = 2.672 R , M1 = 1.175 M , M2 = 0.286 M , R1 = 1.346 R , and R2 = 0.710 R . Finally, we discuss the evolutionary condition of the system.

Bu çalışmada, KIC7542091 sisteminin Kepler Uzay Teleskobu ile alınmış yüksek duyarlıklı fotometrik verileri kullanılarak çevrimsel aktivitenin yapısı ortaya konulmuştur. Sistemin toplam 18 ayrı çeyrekte (quarter) alınmış ışık eğrileri dikkate alınarak maksimum ve minimum parlaklıkları ile bu parlaklıklar arasındaki farklar incelenmiş ve yaklaşık 150 gün dönemli çevrimsel değişimin bulunduğu gösterilmiştir. Bu değişimin, sistemin tayf türüyle (G1V; Frasca vd., 2016) uyumlu bir şekilde aktivite kaynaklı olacağı önerilmektedir. W UMa türü bir değişen olan bu sistemin fiziksel ve geometrik parametrelerine ilişkin çalışmalar hem Kepler Uzay Teleskobu, hem de TESS gözlemlerine dayalı olarak sürdürülmektedir.

We present the results of our investigation on the geometrical and physical parameters of the W UMa type binary system GW Cnc. We analyzed the the photometric data obtained in 2010 and 2011 at Ankara University Observatory (AUO) and the spectroscopic data obtained in 2010 at TUBITAK National Observatory (TUG) by using the Wilson-Devinney (2013 revision) code to obtain the absolute and geometrical parameters. We derived masses and radii of the eclipsing system to be M 1 = 0.257M ⊙ , M 2 = 0.971M ⊙ , R 1 = 0.526R ⊙ and R 2 = 0.961R ⊙ with an orbital inclination i(•) = 83.38 ± 0.25 and we determined the GW Cnc system to be a W-type W UMa over-contact binary with a mass ratio of q = 3.773 ± 0.007.