搜索结果: 1-14 共查到“天文学 Past”相关记录14条 . 查询时间(0.078 秒)
Astronomers discover dark past of planet-eating ‘Death Star’
Astronomers dark past planet-eating Death Star
2016/12/27
An international team of scientists, including researchers from the University of Chicago, has made the rare discovery of a planetary system with a host star similar to Earth’s sun. Especially intrigu...
Can a Satellite Galaxy Merger Explain the Active Past of the Galactic Center?
Satellite Galaxy Merger Explain Active Past Galactic Center
2011/10/9
Observations of the Galactic Center (GC) have accumulated a multitude of "forensic" evidence indicating that several million years ago the center of the Milky Way galaxy was teaming with starforming a...
Planetary Nebula Surveys: Past, Present and Future
Stars post-AGB – planetary nebulae general – surveys general
2010/11/10
In this review we cover the detection, identification and astrophysical importance of planetary nebulae (PN). The legacy of the historic Perek & Kohoutek and Acker et al. catalogues is briefly covered...
Panspermia, Past and Present: Astrophysical and Biophysical Conditions for the Dissemination of Life in Space
Radiation pressure Cosmic rays Micro-organisms Viruses Information
2010/11/9
Astronomically, there are viable mechanisms for distributing organic material throughout the Milky Way. Biologically, the destructive effects of ultraviolet light and cosmic rays means that the majori...
Time-variability in the Interstellar Boundary Conditions of the Heliosphere over the past 60,000 years: Impact of the Solar Journey on the Galactic Cosmic Ray Flux at Earth
Time-variability the Interstellar Boundary Conditions
2011/1/10
During the solar journey through galactic space, variations in the physical properties of the surrounding interstellar material (ISM) modify the heliosphere and modulate the flux of galactic cosmic ra...
Could the Magellanic Clouds be tidal dwarves expelled from a past-merger event occurring in Andromeda?
Galaxy Astrophysics (astro-ph.GA)
2011/1/4
The Magellanic Clouds are often considered as outliers in the satellite system of the Milky Way because they are irregular and gas-rich galaxies. From their large relative motion, they are likely from...
The power spectrum of the residual rotation curve velocity as a probe of past mergers
Galaxy Astrophysics (astro-ph.GA)
2010/12/27
According to the $\Lambda CDM$ cosmological framework, galaxies underwent multiple mergers in their history. In this paper we propose to use the power spectrum of the residual fluctuations of the rota...
A past capture event at Sagittarius A* inferred from the fluorescent X-ray emission of Sagittarius B clouds
High Energy Astrophysical Phenomena (astro-ph.HE) Galaxy Astrophysics (astro-ph.GA)
2010/12/27
The fluorescent X-ray emission from neutral iron in the molecular clouds (Sgr B) indicates that the clouds are being irradiated by an external X-ray source. The source is probably associated with the ...
Gas Accretion in the M32 Nucleus: Past & Present
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Galaxy Astrophysics (astro-ph.GA)
2010/12/27
Using adaptive optics assisted Gemini/NIFS data, I study the present and past gas accretion in the central 3" of the M32 nucleus. From changes in the spectral slope and CO line depths near the center,...
Helioseismology and the Solar Cycle: Past, Present and Future
Helioseismology solar activity cycle tachocline farside imaging
2010/9/15
A major goal of helioseismology is to understand the mechanism of the solar cycle. In this paper, some results of helioseismic observations relevant to the cycle are briefly reviewed, the current stat...
Can past gamma-ray bursts explain both INTEGRAL and PAMELA/Fermi anomalies simultaneously?
Gamma ray bursts gamma-ray bursts
2010/3/9
Gamma-ray bursts (GRB) have been invoked to explain both the 511 keV emission from the galactic bulge and the high-energy positron excess inferred from the PAMELA and Fermi data. While independent exp...
Asteroseismology：Past, Present and Future
Asteroseismology stellar pulsation variable stars
2009/5/12
Asteroseismology studies stars with a wide variety of interior
and surface conditions. For two decades asteroseismic techniques have
been applied to many pulsating stars across the HR diagram. Aster...
Helioseismology and the Solar Cycle：Past, Present and Future
Helioseismology solar activity cycle tachocline farsideimaging
2009/5/6
A major goal of helioseismology is to understand the
mechanism of the solar cycle. In this paper, some results of helioseismic
observations relevant to the cycle are briefly reviewed, the current st...
THE ANTHROPIC ARGUMENT AGAINST INFINITE PAST AND THE EDDINGTON-LEMAITRE UNIVERSE
cosmology EDDINGTON-LEMAITRE UNIVERSE INFINITE PAST
2009/3/18
This study in the philosophy of cosmology is a part of an ongoing
effort to investigate and reassess the importance of the anthropic (Davies-Tipler)
argument against cosmologies containing the past ...