搜索结果: 61-75 共查到“知识库 天体测量学”相关记录294条 . 查询时间(3.441 秒)
日食与月食现象的定量新解
日食 月食 视觉
2011/9/26
人们虽然对日食和月食现象的认识比较深刻，但都是从定性的角度认识。本文依据人体眼睛的成像规律，得出了一种与物体视觉大小有关的结论。利用这个结论，定量地解释了日全食和日环食的形成原因，也定量解释了月食的形成原因以及为什么没有月环食这一天文现象。这一种研究方法是对“食分”说的量化处理。为肉眼观察天体提供了一种全新的指导方法。
远距离物体视觉感知规律的研究
视觉大小 视觉可见性 视觉感知 行星
2011/9/26
在“日食与月食现象的新解”这一篇论文的基础上，进一步深入探讨，研究远距离物体的视觉感知规律。利用这个规律，从一个全新的角度，定量地解释了以下的一些现象--太阳系的地外七大行星的肉眼可见性以及“在太空看不到长城”这一结论等。而在以前，人们虽然这些现象的认识比较深刻，但大都是从定性的角度认识。这种研究方法新颖独特，为肉眼观察天体和从太空看地球上物体的视觉可见性提供了一种全新的指导方法。
Dark goo: Bulk viscosity as an alternative to dark energy
dark energy theory cosmological perturbation theory
2011/9/29
We present a simple (microscopic) model in which bulk viscosity plays a role in explaining the present acceleration of the universe. The effect of bulk viscosity on the Friedmann equations is to turn ...
Orbital effects of the time-dependent component of the Pioneer anomaly
Orbital effects time-dependent component Pioneer anomaly
2011/10/17
We work out the impact that the recently determined time-dependent component of the Pioneer Anomaly (PA), interpreted as an additional exotic acceleration of gravitational origin with respect to the w...
Maximum-likelihood reconstruction of photon returns from simultaneous analog and photon-counting lidar measurements
Maximum-likelihood reconstruction photon returns simultaneous analog photon-counting lidar
2011/10/18
We present a novel method for combining the analog and photon-counting measurements of lidar transient recorders into reconstructed photon returns. The method takes into account the statistical proper...
The conservative cascade of kinetic energy in compressible turbulence
hydrodynamics methods: numerical turbulence
2011/10/14
The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We present the first direct evidence that mean kinetic energy cascades conservativel...
Mass segregation and fractal substructure in young massive clusters: (I) the McLuster code and method calibration
galaxies: star clusters: individual: R136 — galaxies: star formation —methods: data analysis — Magellanic Clouds
2011/10/8
By analysing models of the young massive cluster R136 in 30 Doradus, set-up using the herewith introduced and publicly made available code McLuster, we investigate and compare different methods for de...
Detectability of GRB optical afterglows with Gaia satellite
Detectability optical Gaia satellite
2011/10/9
With the launch of Gaia satellite, detection of many different types of transient sources will be possible, one of them being optical afterglows of gamma-ray bursts (GRBs). Using the knowledge of the ...
Detection of jet precession in the active nucleus of M81
Galaxies: Individual: M81 – galaxies: active – galaxies: jets – galaxies: nuclei – radio continuum: galaxies–radiation mechanisms: nonthermal – astrometry
2011/9/27
(See the complete and formatted abstract in the paper). We report on VLBI monitoring of the low-luminosity AGN (LLAGN) in M81 at 1.7, 2.3, 5, and 8.4GHz. These observations are phase-referenced to the...
High precision astrometry mission for the detection and characterization of nearby habitable planetary systems with the Nearby Earth Astrometric Telescope (NEAT)
Exoplanets Planetary systems Planetary formation Astrometry Space Mission
2011/10/11
A complete census of planetary systems around a volume-limited sample of solar-type stars (FGK dwarfs) in the Solar neighborhood with uniform sensitivity down to Earth-mass planets within their Habita...
Accelerating Radio Astronomy Cross-Correlation with Graphics Processing Units
Radio astronomy Graphics Processing Unit Signal Processing Correlation
2011/10/13
We present a highly parallel implementation of the cross-correlation of time-series data using graphics processing units (GPUs), which is scalable to hundreds of independent inputs and suitable for th...
Observing Conditions for Submillimeter Astronomy
Atmospheric e ects Site testing Submillimeter general
2011/10/20
Consistently superb observing conditions are crucial for achieving the scientific objectives of a telescope. Submillimeter astronomy is possible only at a few exceptionally dry sites, notably Mauna Ke...
Pulsar timing analysis in the presence of correlated noise
pulsars: general – methods: data analysis
2011/10/17
Pulsar timing observations are usually analysed with least-square-fitting procedures under the assumption that the timing residuals are uncorrelated (statistically "white"). Pulsar observers are well ...
Local Scale-Dependent Non-Gaussian Curvature Perturbations at Cubic Order
E ective Field Theory Cosmology In ation Non-Gaussianity
2011/10/17
We calculate non-Gaussianities in the bispectrum and trispectrum arising from the cubic term in the local expansion of the scalar curvature perturbation. We compute to three-loop order and for general...
Hidden SUSY at the LHC: the light higgsino-world scenario and the role of a lepton collider
Supersymmetry Phenomenology Supersymmetric Standard Model Large Hadron Collider
2011/10/14
While the SUSY flavor, CP and gravitino problems seem to favor a very heavy spectrum of matter scalars, fine-tuning in the electroweak sector prefers low values of superpotential mass \mu. In the limi...