Space

Distant galaxy opens window into the early universe

Light from the primordial galaxy, dubbed "MACS 1149-JD", traveled approximately 13.2 billion light-years before reaching NASA's telescopes
Light from the primordial galaxy, dubbed "MACS 1149-JD", traveled approximately 13.2 billion light-years before reaching NASA's telescopes

A team of Johns Hopkins University astronomers have spotted what may well be the most distant galaxy ever detected. Dubbed "MACS 1149-JD", the discovery provides insight into the most remote epoch of cosmic history, as light captured from the faint galaxy shone forth when the universe was just 500 million years old – or 3.6 percent of its present age.

The Johns Hopkins University astronomers believe the distant MACS 1149-JD galaxy to have been observed at a time when it was less than 200 million years old, and it is further thought to be amongst the galaxies which played an important role in the epoch of reionization, the event that signaled the end of the universe’s so called "Dark Ages."

"In essence, during the epoch of reionization, the lights came on in the universe," explains paper co-author Leonidas Moustakas, a research scientist at NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, California.

The observation was made with the combined power of NASA’s Spitzer and Hubble space telescopes, aided by a cosmic magnification phenomenon known as gravitational lensing.

As predicted in Albert Einstein's general theory of relatively, gravitational lensing allows astronomers to view objects further away than would otherwise be possible, by making use of the gravity of foreground objects which warp and magnify the light from background objects. In this case, a massive galaxy cluster situated between our own galaxy and the early galaxy magnified the latter's light, making the remote object approximately 15 times brighter.

"This galaxy is the most distant object we have ever observed with high confidence," said Wei Zheng, principal research scientist at The Henry A. Rowland Department of Physics and Astronomy at Johns Hopkins' Krieger School of Arts and Sciences, and lead author of a paper which appeared in Nature on September 20. "Future work involving this galaxy – as well as others like it that we hope to find – will allow us to study the universe's earliest objects and how the Dark Ages ended."

The remote galaxy is small and compact, containing only around one percent of the Milky Way’s mass, and this fits in with leading cosmological theories which posit that during the universe's infancy, initial galaxies indeed started out very small, before progressively merging and accumulating into the sizable galaxies of the later universe.

Astronomers plan to further study the rise of the first stars and galaxies, and the epoch of reionization, with Spitzer and Hubble’s successor – NASA's James Webb Telescope, slated for launch in 2018.

Source: Johns Hopkins University

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5 comments
Artisteroi Rlsh Gadgeteer
if the universe is infinite, and spherical, how do you know we are not looking all the way across and back at our own galaxy (or other known galaxy) a long long time ago? The light just running around in circles, forever?
also, isnt it possible that the edge we see "appears" to be the early universe only because there isnt enough time for the light to reach us since then? IE the universe can go much much further than we can see, but is expanding at a rate that will prevent the light form ever reaching here for us to see?
think about it
Thomson Burtis
The universe is not "spherical" in nature, but rather finite but unbounded. However, Mark Mason offers a new “quantum gravity” theory of the structure of the Universe, under the name 'Universal Field Cosmology', that leads to simple derivations of the Lorentz Transformation for time and E = mc² and an explanation of gravity and inertia in terms of the interaction of fundamental particles. The theory also explains some other previously puzzling things about the Universe, including what it is in space that is “bent” by massive objects to create gravitational fields, and how this bending then creates the force of gravity. It goes on to predict that gravity becomes a repulsive force at great distance, explaining why the expansion of the Universe is accelerating without needing to propose the existence of “dark energy.” This theory’s formula for gravity gives a value for the acceleration of the expansion of the Universe that is close to what astronomers have measured. The theory also explains the anomalies in galactic rotation that “dark matter” has been inferred from, without the need for dark matter. It does this in terms of a prediction of the theory about how gravitation is affected around the supermassive black holes that are at the center of most galaxies. In addition, this theory explains how the fast solar wind gets its energy, and why areas of the Universe populated by superclusters of galaxies have a “flat” geometry while on a larger scale it is curved, and suggests a function for Cosmic Microwave Background Radiation that explains the puzzling level of organization and complexity in the universe. This theory achieves these things by assuming that the electromagnetic energy of the universe is all a part of a “stationary” universal field field and that all matter is moving at the speed of light, then showing through a simple thought experiment that an absolute frame of reference for velocity is compatible with an isotropic Universe, and following the possibilities these two things open up. Because this is a new way of looking at the universe, it does appear to open up many new possibilities in Physics. (a new “quantum gravity” theory of the structure of the Universe that leads to simple derivations of the Lorentz Transformation for time and E = mc² and an explanation of gravity and inertia in terms of the interaction of fundamental particles. The theory also explains some other previously puzzling things about the Universe, including what it is in space that is “bent” by massive objects to create gravitational fields, and how this bending then creates the force of gravity. It goes on to predict that gravity becomes a repulsive force at great distance, explaining why the expansion of the Universe is accelerating without needing to propose the existence of “dark energy.” This theory’s formula for gravity gives a value for the acceleration of the expansion of the Universe that is close to what astronomers have measured. The theory also explains the anomalies in galactic rotation that “dark matter” has been inferred from, without the need for dark matter. It does this in terms of a prediction of the theory about how gravitation is affected around the supermassive black holes that are at the center of most galaxies. In addition, this theory explains how the fast solar wind gets its energy, and why areas of the Universe populated by superclusters of galaxies have a “flat” geometry while on a larger scale it is curved, and suggests a function for Cosmic Microwave Background Radiation that explains the puzzling level of organization and complexity in the universe. This theory achieves these things by assuming that the electromagnetic energy of the universe is all a part of a “stationary” universal field field and that all matter is moving at the speed of light, then showing through a simple thought experiment that an absolute frame of reference for velocity is compatible with an isotropic Universe, and following the possibilities these two things open up. Because this is a new way of looking at the universe, it does appear to open up many new possibilities in Physics. (http://www.markmason.net/cothlong.htm)
You could also examine 'Geometry Of The Big Bang', by Johannes Koelman(http://www.science20.com/hammock_physicist/geometry_big_bang-90461).
Could it be that the space-time our astronomer lives in is not Minkowskian but curved? Curved in such a way that both light rays reaching the astronomer originate from one and the same event? The answer is "yes", this is very well possible. One can build a curved space-time consisting of left- and right-oriented lines of causations that cross each other. What might surprise you is that this can be achieved without bending the straight paths of causation. There is one unique way to achieve this, and it requires us to go one dimension higher than the space-time we want to describe. The curved space-time thus created is again two-dimensional (one spatial and one temporal dimension) and takes the shape of a hyperboloid embedded in a three-dimensional (two spatial dimensions and one time dimension) space-time.
De Sitter universe with one spatial (circumferential) and one time (upward) dimension. This universe is build from straight light paths (red and blue lines) embedded in a 3D Minkowski space-time. This 3D background serves as an aid in visualizing the universe, and is not in any way part of the universe.
This is the De Sitter universe with 1+1 space-time dimensions. The lines of causation (red and blue lines) remain straight, and run without beginning or end. The universe thus created is past and future infinite, and the big bang is replaced by a compact phase: a 'big bottleneck' also referred to as a 'big bounce'. At this bottleneck the universe is hot and dense and opaque to any light. Away from the bottleneck, the universe expands both towards future infinity and towards past infinity.
This is an utterly simple universe model that at one fell swoop eliminates a multitude of issues surrounding big-bang cosmologies. Firstly, there is no singularity plaguing the model. At the 'big bottleneck' the universe attains a minimum size, but at no stage of evolution does the size of the universe drop to zero. Secondly, there is no issue of lines of causation terminating at a time zero. No fine-tuning nor any special boundary conditions are required at time zero. Thirdly, the universe is time-symmetric and therefore fully compatible with the known fundamental laws of physics that are strictly time symmetric. And finally, with this cosmological model the "dawn of time" has disappeared and with it has the horizon problem. More in particular, when tracing back the opposing red and blue light rays arriving at an event in the distant future (and event at a distance from the bottleneck much further away than the bottleneck diameter), one notices that both light rays, when continued through the bottleneck towards time "minus infinity", get arbitrarily close in terms of distances expressed in the local diameter of the universe (the local circumference of the hyperboloid).
We are living in another grand time for cosmology and astrophysics.
nutcase
"But finite but unbounded" sounds to me more like a politician's explanation of government monetary policy than cosmology.
Maybe "MACS 1149-JD" is inhabited by economists?
Nasa-Vet
Can someone explain to me, in layman's terms, how we can have physically moved from the location of the initial big bang to our current physical location, so that it should take 13.5 billion years for visible evidence of this big bang to finally catch up with us? It seems to me that we would have had to travel considerably faster than the speed of light to be able to look back at what happened 13.5 billion years ago. I feel so unworthy.
jochair
This is Jochai's first law of the universe:, There are no limits or borders to the Universe. There is no sense in asking; What lies beyond the universe? there is nothing there. What was there before the universe? There was no time than. How old is the universe?, The age of the universe is infinite. Jochai Rubinstein.