Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Seeing the Birth of the Universe in an Atom of Hydrogen

06.09.2012
TAU uses radio waves to uncover oldest galaxies yet
Windows to the past, stars can unveil the history of our universe, currently estimated to be 14 billion years old. The farther away the star, the older it is — and the oldest stars are the most difficult to detect. Current telescopes can only see galaxies about 700 million years old, and only when the galaxy is unusually large or as the result of a big event like a stellar explosion.

Now, an international team of scientists led by researchers at Tel Aviv University have developed a method for detecting galaxies of stars that formed when the universe was in its infancy, during the first 180 million years of its existence. The method is able to observe stars that were previously believed too old to find, says Prof. Rennan Barkana of TAU's School of Physics and Astronomy.

Published in the journal Nature, the researchers' method uses radio telescopes to seek out radio waves emitted by hydrogen atoms, which were abundant in the early days of the universe. Emitting waves measuring about eight inches (21 centimeters) long, the atoms reflect the radiation of the stars, making their emission detectable by radio telescopes, explains Prof. Barkana. This development opens the way to learning more about the universe's oldest galaxies.

Reading signals from the past

According to Prof. Barkana, these waves show a specific pattern in the sky, a clear signature of the early galaxies, which were one-millionth the size of galaxies today. Differences in the motion of dark matter and gas from the early period of the universe, which affect the formation of stars, produce a specific fluctuation pattern that makes it much easier to distinguish these early waves from bright local radio emissions.

The intensity of waves from this early era depends on the temperature of the gas, allowing researchers to begin to piece together a rough map of the galaxies in an area of the sky. If the gas is very hot, it means that there are many stars there; if cooler, there are fewer stars, explains Prof. Barkana.

These initial steps into the mysterious origins of the universe will allow radio astronomers to reconstruct for the first time what the early universe looked like, specifically in terms of the distribution of stars and galaxies across the sky, he believes.

A new era

This field of astronomical research, now being called "21-centimeter cosmology," is just getting underway. Five different international collaborations are building radio telescopes to detect these types of emissions, currently focusing on the era around 500 million years after the Big Bang. Equipment can also be specifically designed for detecting signals from the earlier eras, says Prof. Barkana. He hopes that this area of research will illuminate the enigmatic period between the birth of the universe and modern times, and allow for the opportunity to test predictions about the early days of the universe.

"We know a lot about the pristine universe, and we know a lot about the universe today. There is an unknown era in between when there was hot gas and the first formation of stars. Now, we are going into this era and into the unknown," says Prof. Barkana. He expects surprises along the way, for example involving the properties of early stars, and that observations will reveal a more complicated cosmological reality than was predicted by their models.

George Hunka | EurekAlert!
Further information:
http://www.aftau.org
http://www.aftau.org/site/News2?page=NewsArticle&id=17151

More articles from Physics and Astronomy:

nachricht Upside down and inside out
27.04.2015 | University of Cambridge

nachricht Fast and Accurate 3-D Imaging Technique to Track Optically-Trapped Particles
24.04.2015 | Korea Advanced Institute of Science and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fast and Accurate 3-D Imaging Technique to Track Optically-Trapped Particles

KAIST researchers published an article on the development of a novel technique to precisely track the 3-D positions of optically-trapped particles having complicated geometry in high speed in the April 2015 issue of Optica.

Daejeon, Republic of Korea, April 23, 2015--Optical tweezers have been used as an invaluable tool for exerting micro-scale force on microscopic particles and...

Im Focus: NOAA, Tulane identify second possible specimen of 'pocket shark' ever found

Pocket sharks are among the world's rarest finds

A very small and rare species of shark is swimming its way through scientific literature. But don't worry, the chances of this inches-long vertebrate biting...

Im Focus: Drexel materials scientists putting a new spin on computing memory

Ever since computers have been small enough to be fixtures on desks and laps, their central processing has functioned something like an atomic Etch A Sketch, with electromagnetic fields pushing data bits into place to encode data.

Unfortunately, the same drawbacks and perils of the mechanical sketch board have been just as pervasive in computing: making a change often requires starting...

Im Focus: Exploding stars help to understand thunderclouds on Earth

How is lightning initiated in thunderclouds? This is difficult to answer - how do you measure electric fields inside large, dangerously charged clouds? It was discovered, more or less by coincidence, that cosmic rays provide suitable probes to measure electric fields within thunderclouds. This surprising finding is published in Physical Review Letters on April 24th. The measurements were performed with the LOFAR radio telescope located in the Netherlands.

How is lightning initiated in thunderclouds? This is difficult to answer - how do you measure electric fields inside large, dangerously charged clouds? It was...

Im Focus: On the trail of a trace gas

Max Planck researcher Buhalqem Mamtimin determines how much nitrogen oxide is released into the atmosphere from agriculturally used oases.

In order to make statements about current and future air pollution, scientists use models which simulate the Earth’s atmosphere. A lot of information such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

HHL Energy Conference on May 11/12, 2015: Students Discuss about Decentralized Energy

23.04.2015 | Event News

“Developing our cities, preserving our planet”: Nobel Laureates gather for the first time in Asia

23.04.2015 | Event News

HHL's Entrepreneurship Conference on FinTech

13.04.2015 | Event News

 
Latest News

Northwestern scientists develop first liquid nanolaser

27.04.2015 | Life Sciences

The Future of Oil and Gas: Pumping Innovation in the Oil and Gas Industry

27.04.2015 | Power and Electrical Engineering

Upside down and inside out

27.04.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>