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Astrophysical Naturalness [PDF]

Frontiers in Astronomy and Space Sciences, 2022
I suggest that stars introduce mass and density scales that lead to “naturalness” in the Universe. Namely, two ratios of order unity. 1) The combination of the stellar mass scale, M*(c, ℏ, G, mp, me, e, …), with the Planck mass, MPl, and the Chandrasekhar mass leads to a ratio of order unity that reads NPl*≡MPl/(M*mp2)1/3≃0.15−3, where mp is the proton
openaire   +3 more sources

Careers in astronomy in Germany and the UK [PDF]

Astronomy and Geophysics, Vol. 55, pp. 2.32-2.37, 2014, 2014
We discuss the outcomes of surveys addressing the career situation of astronomers in Germany and the UK, finding social and cultural differences between communities as well as gender bias in both.
arxiv   +1 more source

The Mastcam‐Z Radiometric Calibration Targets on NASA's Perseverance Rover: Derived Irradiance Time‐Series, Dust Deposition, and Performance Over the First 350 Sols on Mars

Earth and Space Science, Volume 9, Issue 12, December 2022., 2022
Abstract The Mastcam‐Z radiometric calibration targets mounted on the NASA's Perseverance rover proved to be effective in the calibration of Mastcam‐Z images to reflectance (I/F) over the first 350 sols on Mars. Mastcam‐Z imaged the calibration targets regularly to perform reflectance calibration on multispectral image sets of targets on the Martian ...
M. Merusi, K. B. Kinch, M. B. Madsen, J. F. Bell III, J. N. Maki, A. G. Hayes, J. Joseph, J. R. Johnson, M. Rice, E. A. Cloutis, D. Applin, M. T. Lemmon, A. F. Vaughan, J. I. Núñez, E. Jensen, J. Z. Kristensen, K. Paris, E. Cisneros, M. R. Kennedy, O. Gasnault   +19 more
wiley   +1 more source

Stream‐Lake Connectivity Is an Important Control of Fluvial CO2 Concentrations and Emissions in Catchments

Earth and Space Science, Volume 9, Issue 12, December 2022., 2022
Abstract Streams in cultivated lowlands are commonly supersaturated with CO2 and are a source of CO2 to the atmosphere. Great uncertainties exist regarding the spatiotemporal variations of CO2 concentrations and emission rates in stream‐lake fluvial networks and small streams with variable plant cover.
Kaj Sand‐Jensen, Tenna Riis, Johan Emil Kjær, Kenneth Thorø Martinsen   +3 more
wiley   +1 more source

Astrophysics in 1995 [PDF]

Publications of the Astronomical Society of the Pacific, 1996
Ap95 differs from Ap91 to Ap94 primarily in Ap number. That is, it once again attempts to highlight some areas of our mutual science where a major event has occurred during the year (a possible solution of the Type II supernova problem, the faintness of quasar host galaxies, and the collision of Shoemaker-Levy 9 with Jupiter), but also to focus on some
Trimble, Virginia, Leonard, Peter JT
openaire   +2 more sources

Generalization Ability of Deep Learning Algorithms Trained Using SEM Data for Objects Classification

Radio Science, Volume 57, Issue 12, December 2022., 2022
Abstract This paper proposes an efficient method to determine the material of spherical objects and the location of the receiving antenna relative to the object in bi‐static measurements using supervised learning techniques. From a single observation, we compare classification performances resulting from the application of several classifiers on ...
Yasmina Zaky, Nicolas Fortino, Benoit Miramond, Jean‐Yves Dauvignac   +3 more
wiley   +1 more source

Astrophysics in 1996 [PDF]

Publications of the Astronomical Society of the Pacific, 1997
The loudest astronomical headlines of the year came from both very near (planets orbiting stars in the solar neighborhood) and very far (galaxies and parts of galaxies at redshifts of 1 to 3 and more). We explore these and other happenings in our Solar System (Galileo at Jupiter, Comet Hyakutake), Milky Way (the bursting pulsar, spotted stars), Local ...
Trimble, Virginia, McFadden, Lucy Ann
openaire   +2 more sources

Self‐Detecting Mid‐Infrared Dual‐Comb Spectroscopy Based on High‐Speed Injection‐Locked Quantum Cascade Lasers

Advanced Photonics Research, EarlyView.
A compact self‐detecting dual‐comb spectroscopy (DCS) system based on dispersion‐engineered, high‐speed packaged quantum cascade lasers (QCLs) at λ≈4.6 μm under coherent injection locking is demonstrated. Broad multiheterodyne comb signal with reduced tooth linewidths by orders of magnitude is recorded.
Yu Ma, Dapeng Wu, Ruixin Huang, Shichen Zhang, Binru Zhou, Zejun Ma, Yongqiang Sun, Junqi Liu, Ning Zhuo, Jinchuan Zhang, Shenqiang Zhai, Shuman Liu, Fengqi Liu, Manijeh Razeghi, Quanyong Lu   +14 more
wiley   +1 more source

A Proper Use of the Adjacent Land‐Based Observatory Magnetic Field Data to Account for the Geomagnetic Disturbances During Offshore Directional Drilling

Space Weather, Volume 20, Issue 12, December 2022., 2022
Abstract Directional drilling in the oil fields relies particularly on the “on‐fly” measurements of the natural magnetic field (measurements while drilling; MWD); the MWD are eventually used to construct the well path. These measurements are the superposition of the signals from the internal, core and crustal, and external, ionospheric and ...
Mikhail Kruglyakov, Alexey Kuvshinov, Manoj Nair   +2 more
wiley   +1 more source

Astrophysical symmetries [PDF]

Proceedings of the National Academy of Sciences, 1996
Astrophysical objects, ranging from meteorites to the entire universe, can be classified into about a dozen characteristic morphologies, at least as seen by a blurry eye. Some patterns exist over an enormously wide range of distance scales, apparently as a result of similar underlying physics.
openaire   +4 more sources