Results 21 to 30 of about 6,767,247 (161)

Babylonian Shadow-Length Schemes: Between Mathematics and Astronomy

Claroscuro. Revista del Centro de Estudios sobre Diversidad Cultural, 2021
A simple mathematical scheme to represent the variation in the length of the shadow cast by a vertical gnomon at different times of day and in different months of the year is presented in the early astronomical compendium MUL.APIN.
J. Steele
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Prevalence of a growth mindset among introductory astronomy students [PDF]

Physical Review Physics Education Research
While many previous studies have indicated that encouraging a growth mindset can improve student learning outcomes, this conclusion’s applicability to college-level astronomy classrooms remains poorly understood owing to the variation in students ...
M. Prescott, Laura Madson, Sandra M. Way, Kelly N. Sanderson   +3 more
semanticscholar   +1 more source

TESS Timings of 31 Hot Jupiters with Ephemeris Uncertainties

The Astrophysical Journal Supplement Series, 2023
A precise transit ephemeris serves as the premise for follow-up exoplanet observations. We compare TESS Object of Interest (TOI) transit timings of 262 hot Jupiters with the archival ephemeris and find 31 of them having TOI timing offsets, among which ...
Su-Su Shan, Fan Yang, You-Jun Lu, Xing Wei, Wen-Wu Tian, Hai-Yan Zhang, Rui Guo, Xiao-Hong Cui, Ai-Yuan Yang, Bo Zhang, Ji-Feng Liu   +10 more
doaj   +1 more source

Inelastic O+H collisions and the O I 777 nm solar centre-to-limb variation [PDF]

Astronomy & Astrophysics, 2018
The O I 777 nm triplet is a key diagnostic of oxygen abundances in the atmospheres of FGK-type stars; however, it is sensitive to departures from local thermodynamic equilibrium (LTE). The accuracy of non-LTE line formation calculations has hitherto been
A. Amarsi, P. Barklem, M. Asplund, R. Collet, O. Zatsarinny   +4 more
semanticscholar   +1 more source

Height variation of the cutoff frequency in a sunspot umbra [PDF]

Astronomy & Astrophysics, 2018
Context. In the solar atmosphere, the acoustic cutoff frequency is a local quantity that depends on atmospheric height. It separates low-frequency evanescent waves from high-frequency propagating waves. Aims.
T. Felipe, C. Kuckein, I. Thaler
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Activity induced variation in spin-orbit angles as derived from Rossiter–McLaughlin measurements [PDF]

Astronomy & Astrophysics, 2018
One of the most powerful methods used to estimate sky-projected spin-orbit angles of exoplanetary systems is through a spectroscopic transit observation known as the RossiterMcLaughlin (RM) effect.
M. Oshagh, A. Triaud, A. Burdanov, P. Figueira, A. Reiners, N. C. Santos, J. Faria, G. Boué, R. Díaz, S. Dreizler, S. Boldt, L. Delrez, E. Ducrot, M. Gillon, A. Mesa, E. Jehin, S. Khalafinejad, S. Kohl, L. Serrano, S. Udry   +19 more
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Long term changes in EUV and X-ray emissions from the solar corona and chromosphere as measured by the response of the Earth’s ionosphere during total solar eclipses from 1932 to 1999 [PDF]

Annales Geophysicae, 2001
Measurements of the ionospheric E region during total solar eclipses in the period 1932–1999 have been used to investigate the fraction of Extreme Ultra Violet and soft X-ray radiation, 8, that is emitted from the limb corona and chromosphere.
C. J. Davis, C. J. Davis, E. M. Clarke, R. A. Bamford, M. Lockwood, S. A. Bell   +5 more
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Rotational variation of the linear polarization of the asteroid (3200) Phaethon as evidence for inhomogeneity in its surface properties★ [PDF]

Monthly Notices of the Royal Astronomical Society Letters, 2018
This work was supported via a grant (ST/M000834/1) from the UK Science and Technology Facilities Council. We gratefully acknowledge observing grant support from the Institute of Astronomy and Rozhen National Astronomical Observatory, Bulgarian Academy of
G. Borisov, M. Devogèle, A. Cellino, S. Bagnulo, A. Christou, P. Bendjoya, J. Rivet, L. Abe, D. Vernet, Z. Donchev, Y. Krugly, I. Belskaya, T. Bonev, D. Steeghs, D. Galloway, V. Dhillon, P. O’Brien, D. Pollacco, S. Poshyachinda, G. Ramsay, E. Thrane, K. Ackley, E. Rol, K. Ulaczyk, Ry Cutter, M. Dyer   +25 more
semanticscholar   +1 more source

Total-variation methods for gravitational-wave denoising: Performance tests on Advanced LIGO data [PDF]

Physical Review D, 2018
We assess total-variation methods to denoise gravitational-wave signals in real noise conditions by injecting numerical-relativity waveforms from core-collapse supernovae and binary black hole mergers in data from the first observing run of Advanced LIGO.
A. Torres-Forné, E. Cuoco, A. Marquina, J. Font, J. Ib'anez   +4 more
semanticscholar   +1 more source

Conceptual Design of the NISS onboard NEXTSat-1 [PDF]

Journal of Astronomy and Space Sciences, 2014
The NISS onboard NEXTSat-1 is being developed by Korea astronomy and space science institute (KASI). For the study of the cosmic star formation history, the NISS performs the imaging spectroscopic observation in the near-infrared range for nearby ...
Woong-Seob Jeong, Sung-Joon Park, Kwijong Park, Dae-Hee Lee, Jeonghyun Pyo, Bongkon Moon, Youngsik Park, Il-Joong Kim, Won-Kee Park, Duk-Hang Lee, Chan Park, Kyeongyeon Ko, Toshio Matsumoto, Norihide Takeyama, Akito Enokuchi, Goo-Whan Shin, Jangsoo Chae, Uk-Won Nam   +17 more
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