Related papers: A Glimpse of the First Galaxies
The age of the universe in the Big Bang model can be calculated from three parameters: Hubble's constant, h; the mass density of the universe, Omega_m; and the cosmological constant, Omega_lambda. Recent observations of the cosmic microwave…
In the past decade, our understanding of how stars and galaxies formed during the first 5 billion years after the Big Bang has been revolutionized by observations that leverage gravitational lensing by intervening masses, which act as…
It is found that the ages of the most metal-poor Galactic globular clusters are probably around 18 Gyr. On the other hand a Hubble parameter of 82 +/- 8 km/sec/Mpc (in conjunction with the standard Einstein-de Sitter model with an Omega =1…
The James Webb Space Telescope has recently detected massive, fully formed, galaxies at redshifts corresponding to few hundred million years after the Big-Bang. However, our current cosmological model cannot produce such massive systems so…
The solar system has changed dramatically since its birth, and so did our understanding of it. A considerable research effort has been invested in the past decade in an attempt to reconstruct the solar system history, including the earliest…
The scheduled launch of James Webb Space Telescope (JWST) in late 2021 marks a new start for studies of galaxy formation at high redshift z>~6 during the era of Cosmic Reionization. JWST can capture sensitive, high-resolution images and…
[Abridged] Over the past two decades observations and theoretical simulations have established a global frame-work of galaxy formation and evolution in the young Universe. Galaxies formed as baryonic gas cooled at the centres of collapsing…
With the discovery of galaxies that existed when the universe was very young (approximately 5 percent of its current age), of planets not in our own solar system, and with the tantalizing evidence that the conditions for life may have…
The smallest dwarf galaxies are the most straight forward objects in which to study star formation processes on a galactic scale. They are typically single cell star forming entities, and as small potentials in orbit around a much larger…
Observational studies showed that galaxy disks are already in place in the first few billion years of the universe. The early disks detected so far, with typical half-light radii of 3 kiloparsecs at stellar masses around 10^11 M_sun for…
A minimum age of the universe can be estimated directly by determining the age of the oldest objects in the our Galaxy. These objects are the metal-poor stars in the halo of the Milky Way. Recent work on nucleochronology finds that the…
There has been remarkable progress recently in both observational and theoretical studies of galaxy formation and evolution. Largely due to a combination of deep Hubble Space Telescope imaging, Keck spectroscopy, and COBE far-IR background…
Although the universe at redshifts greater than six represents only the first one billion years (<10%) of cosmic time, the dense nature of the early universe led to vigorous galaxy formation and evolution activity which we are only now…
If we are to develop a comprehensive and predictive theory of galaxy formation and evolution, it is essential that we obtain an accurate assessment of how and when galaxies assemble their stellar populations, and how this assembly varies…
In popular cold dark matter cosmological scenarios, stars may have first appeared in significant numbers around a redshift of 10 or so, as the gas within protogalactic halos with virial temperatures in excess of 20,000 K (corresponding to…
A fundamental quest of modern astronomy is to locate the earliest galaxies and study how they influenced the intergalactic medium a few hundred million years after the Big Bang. The abundance of star-forming galaxies is known to decline…
With stunning clarity, JWST has revealed the Universe's first billion years. The scientific community is analyzing a wealth of JWST imaging and spectroscopic data from that era, and is in the process of rewriting the astronomy textbooks.…
Nearly a century after the true nature of galaxies as distant "island universes" was established, their origin and evolution remain great unsolved problems of modern astrophysics. One of the most promising ways to investigate galaxy…
We show that the UV flux of old stellar systems can tell us about their ages. Two independent populations synthesis groups that have had wildly different views have here worked together and generated two solutions that can be easily tested…
If we are to develop a comprehensive and predictive theory of galaxy formation and evolution, it is essential that we obtain an accurate assessment of how and when galaxies assemble their stellar populations, and how this assembly varies…