Results 51 to 60 of about 240,676 (167)

Ionospheric measurements of relative coronal brightness during the total solar eclipses of 11 August, 1999 and 9 July, 1945 [PDF]

Annales Geophysicae, 2000
Swept-frequency (1-10 MHz) ionosonde measurements were made at Helston, Cornwall (50°06'N, 5°18'W) during the total solar eclipse on August 11, 1999. Soundings were made every three minutes.
C. J. Davis, C. J. Davis, M. Lockwood, M. Lockwood, S. A. Bell, S. A. Bell, J. A. Smith, J. A. Smith, E. M. Clarke, E. M. Clarke   +9 more
doaj   +1 more source

Intranight optical variability of radio-quiet BL Lacertae objects

, 2015
Aims: Intranight variation (or microvariation) is a common phenomenon of radio-loud BL Lac objects. However, it is not clear whether the recently found radio-quiet BL Lac objects have the same properties.
Liu, Yuan, Zhang, Jin, Zhang, Shuang Nan
core   +1 more source

TOI-4495: A Pair of Aligned, Near-resonant Sub-Neptunes That Likely Experienced Overstable Migration

The Astronomical Journal
We report the discovery of a sub-Neptune and a Neptune-like planet ( R ${}_{b}=2.4{8}_{-0.10}^{+0.14}$ R _⊕ , R ${}_{c}=4.0{3}_{-0.15}^{+0.23}$ R _⊕ ) orbiting the F-type star TOI-4495.
Mu-Tian Wang, Fei Dai, Hui-Gen Liu, Kento Masuda, Andrew W. Howard, Samuel Halverson, Howard Isaacson, Elina Y. Zhang, Max Goldberg, Huan-Yu Teng, Ryan A. Rubenzahl, Benjamin Fulton, Erik A. Petigura, Steven Giacalone, Luke Handley, David W. Latham, Allyson Bieryla, Ashley Baker, Jerry Edelstein, Steven R. Gibson, Kodi Rider, Arpita Roy, Chris Smith, Josh Walawender, David Rapetti, Jon M. Jenkins, Joshua N. Winn   +26 more
doaj   +1 more source

Intensity interferometry for observation of dark objects

, 2013
We analyze an intensity interferometry measurement carried out with two point-like detectors facing a distant source (e.g., a star) that may be partially occluded by an absorptive object (e.g., a planet).
Erkmen, Baris I., Strekalov, Dmitry V., Yu, Nan   +2 more
core   +1 more source

Exoplanet Ephemerides Change Observations (ExoEcho). II. Transit Timing Variation Analysis of Brown Dwarfs around Solar-type Stars

The Astrophysical Journal
Transit timing variation (TTV) is a useful tool for studying the orbital properties of transiting objects. However, few TTV studies have been done on transiting brown dwarfs (BDs) around solar-type stars.
Wenqin Wang, Xinyue Ma, Zhangliang Chen, Cong Yu, Shangfei Liu, Bo Ma   +5 more
doaj   +1 more source

Numerical self-consistent stellar models of thin disks

, 2005
We find a numerical self-consistent stellar model by finding the distribution function of a thin disk that satisfies simultaneously the Fokker-Planck and Poisson equations.
Aarseth, Ashurov, Cohn, de Zeeuw, de Zeeuw, Eddington, Freeman, Hunter, Jeans, Joshi, Kalnajs, King, Kuzmin, Letelier, M. Ujevic, Mestel, Michie, Michie, Miller, Miller, Miyamoto, Ng, Nishida, P. S. Letelier, Plummer, Rosenbluth, Schwarzschild, Statler, Stone, Takahashi, Takahashi, Teuben, Theuns, Toomre, Ujevic, van Albada, van de Ven, Vandervoort, Vogt, Watanabe, Wilkinson, Yepes   +41 more
core   +1 more source

TrES-1 b: A Case Study in Detecting Secular Evolution of Exoplanet Orbits

The Astronomical Journal
We present a comprehensive analysis of transit, eclipse, and radial velocity data of the hot Jupiter TrES-1 b and confirm evidence of orbital variations on secular timescales.
Simone R. Hagey, Billy Edwards, Angelos Tsiaras, Aaron C. Boley, Anastasia Kokori, Norio Narita, Pedro V. Sada, Filip Walter, Robert T. Zellem, Napaporn A-thano, Kevin B. Alton, Miguel Ángel Álava Amat, Paul Benni, Emmanuel Besson, Patrick Brandebourg, Marc Bretton, Mauro Caló, Martin Valentine Crow, Jean-Christophe Dalouzy, Marc Deldem, Tõnis Eenmäe, Stephane Ferratfiat, Pere Guerra, Gary Vander Haagen, Ken Hose, Adrian Jones, Yves Jongen, Didier Laloum, Stefano Lora, Alessandro Marchini, Jacques Michelet, Matej Mihelčič, Johannes Mieglitz, Eric Miny, David Molina, Mario Morales Aimar, Raphael Nicollerat, Ivo Peretto, Manfred Raetz, François Regembal, Robert Roth, Lionel Rousselot, Mark Salisbury, Darryl Sergison, Anaël Wünsche, Jaroslav Trnka   +45 more
doaj   +1 more source

The exponential pedagogical model applied to Astronomy: A practical case of kinematic stellar velocity calculation

Revista de Investigación de Física
The paradigm of a learning model has been explained and validated in an applied case of an astronomy problem where the data we used are declination, parallax, radial velocity of a star, as well as its annual variation in right ascension and declination. 
Rafael Carlos, Atilio Buendía, Felipe Reyes   +2 more
doaj   +1 more source

Detection of an exoplanet around the evolved K giant HD 66141

, 2012
Aims. We have been carrying out a precise radial velocity (RV) survey for K giants to search for and study the origin of the lowamplitude and long-periodic RV variations. Methods. We present high-resolution RV measurements of the K2 giant HD 66141 from
Han, I., Kim, K. -M., Lee, B. -C., Mkrtichian, D. E., Park, M. -G.   +4 more
core   +1 more source

An Analysis of the Effect on the Data Processing of Korea GPS Network by the Absolute Phase Center Variations of GPS Antenna [PDF]

Journal of Astronomy and Space Sciences, 2006
The International GNSS Service (IGS) has prepared for a transition from the relative phase center variation (PCV) to the absolute PCV, because the terrestrial scale problem of the absolute PCV was resolved by estimating the PCV of the GPS satellites ...
Jeongho Baek, Hyung-Chul Lim, Jung Hyun Jo, Sungki Cho, Jung-Ho Cho   +4 more
doaj   +1 more source