搜索结果: 46-60 共查到“理学 stars”相关记录462条 . 查询时间(0.147 秒)
Washington, D.C.—New modeling studies from Carnegie’s Alan Boss demonstrate that most of the stars we see were formed when unstable clusters of newly formed protostars broke up. These protostars are b...
Scientists have shown how gravitational waves—invisible ripples in the fabric of space and time that propagate through the universe—might be “seen” by looking at the stars. The new model, developed in...
Imagine living on an exoplanet with two suns. One, you orbit and the other is a very bright, nearby neighbor looming large in your sky. With this “second sun” in the sky, nightfall might be a rare eve...
Mixing in star-forming clouds explains why sibling stars look alike(图)
sibling star-forming clouds
2014/9/12
The chemical uniformity of stars in the same cluster is the result of turbulent mixing in the clouds of gas where star formation occurs, according to a study by astrophysicists at the University of Ca...
Why sibling stars look alike: Early, fast mixing in star-birth clouds(图)
star-birth clouds sibling stars look alike
2014/9/12
Stars are made mostly of hydrogen and helium, but they also contain trace amounts of other elements, such as carbon, oxygen, iron, and even more exotic substances. By carefully measuring the wavelengt...
Analyzing sun-like stars that eat Earth-like planets
Analyzing sun-like stars eat Earth-like planets
2014/6/12
Some Sun-like stars are ‘Earth-eaters.’ During their development they ingest large amounts of the rocky material from which ‘terrestrial’ planets like Earth, Mars and Venus are made.
'Death stars' in Orion blast planets before they even form(图)
Death stars they even form planets
2014/3/20
The Orion Nebula is home to hundreds of young stars and even younger protostars known as proplyds. Many of these nascent systems will go on to develop planets, while others will have their planet-form...
Surprising new class of 'hypervelocity stars' discovered escaping the galaxy(图)
hypervelocity stars galaxy
2014/3/17
Top and side views of the Milky Way galaxy show the location of four of the new class of hypervelocity stars. These are sun-like stars that are moving at speeds of more than a million miles per hour r...
A recent question in generalized Ramsey theory is that for fixed positive integers $s\leq t$, at least how many vertices can be covered by the vertices of no more than $s$ monochromatic members of the...
Let A be the adjacency matrix of a graph $X$ and suppose U(t)=exp(itA). We view A as acting on $\cx^{V(X)}$ and take the standard basis of this space to be the vectors $e_u$ for $u$ in $V(X)$. Physici...
Thomas Hinsley Astbury: from an English market town schoolroom to the internal constitution of the stars
Thomas Hinsley Astbury the internal constitution of the stars History and Philosophy of Physics
2012/5/28
T. H. Astbury (1858-1922) was for many years the much-respected headmaster of a boys' junior school in the English market town of Wallingford. By night he was a dedicated amateur astronomer who enjoye...
The study of neutron stars is a topic of central interest in the investigation of the properties of strongly compressed hadronic matter. Whereas in heavy-ion collisions the fireball, created in the co...
Vibrational Instability of Metal-Poor Low-Mass Main-Sequence Stars
Vibrational Instability Metal-Poor Low-Mass Main-Sequence Stars
2012/2/24
We find that low-degree low-order g-modes become unstable in metal-poor low-mass stars due to the $\varepsilon$-mechanism of the pp-chain. Since the outer convection zone of these stars is limited onl...
A lucky imaging multiplicity study of exoplanet host stars
techniques high angular resolution binaries close HD 185269 stars individual HD 126614
2012/2/23
To understand the influence of additional wide stellar companions on planet formation, it is necessary to determine the fraction of multiple stellar systems amongst the known extrasolar planet populat...
A Bayesian Approach to Calibrating Period-Luminosity Relations of RR Lyrae Stars in the Mid-Infrared
statistical methods RR Lyrae distance scale
2012/2/23
A Bayesian approach to calibrating period-luminosity (PL) relations has substantial benefits over generic least-squares fits. In particular, the Bayesian approach takes into account the full prior dis...