Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA’s Hubble Finds Extremely Distant Galaxy through Cosmic Magnifying Glass

17.10.2014

Peering through a giant cosmic magnifying glass, NASA’s Hubble Space Telescope has spotted a tiny, faint galaxy -- one of the farthest galaxies ever seen. The diminutive object is estimated to be more than 13 billion light-years away.

This galaxy offers a peek back to the very early formative years of the universe and may just be the tip of the iceberg.


The mammoth galaxy cluster Abell 2744 is so massive that its powerful gravity bends the light from galaxies far behind it, making these otherwise unseen background objects appear larger and brighter than they would normally.

Image Credit: NASA, J. Lotz, (STScI)

“This galaxy is an example of what is suspected to be an abundant, underlying population of extremely small, faint objects that existed about 500 million years after the big bang, the beginning of the universe,” explained study leader Adi Zitrin of the California Institute of Technology in Pasadena, California.

“The discovery is telling us galaxies as faint as this one exist, and we should continue looking for them and even fainter objects, so that we can understand how galaxies and the universe have evolved over time.”

The galaxy was detected by the Frontier Fields program, an ambitious three-year effort that teams Hubble with NASA’s other great observatories -- the Spitzer Space Telescope and Chandra X-ray Observatory -- to probe the early universe by studying large galaxy clusters.

These clusters are so massive their gravity deflects light passing through them, magnifying, brightening, and distorting background objects in a phenomenon called gravitational lensing. These powerful lenses allow astronomers to find many dim, distant structures that otherwise might be too faint to see.

The discovery was made using the lensing power of the mammoth galaxy cluster Abell 2744, nicknamed Pandora’s Cluster, which produced three magnified images of the same, faint galaxy. Each magnified image makes the galaxy appear 10 times larger and brighter than it would look without the zooming qualities of the cluster.

The galaxy measures merely 850 light-years across -- 500 times smaller than our Milky Way galaxy-- and is estimated to have a mass of only 40 million suns. The Milky Way, in comparison, has a stellar mass of a few hundred billion suns. And the galaxy forms about one star every three years, whereas the Milky Way galaxy forms roughly one star per year. However, given its small size and low mass, Zitrin said the tiny galaxy actually is rapidly evolving and efficiently forming stars.

The astronomers believe galaxies such as this one are probably small clumps of matter that started to form stars and shine, but do not yet have a defined structure. It is possible Hubble is only detecting one bright clump magnified due to the lensing. This would explain why the object is smaller than typical field galaxies of that time.

Zitrin’s team spotted the galaxy’s gravitationally multiplied images using near-infrared and visible-light photos of the galaxy cluster taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys. But they needed to measure how far away it was from Earth.

Usually, astronomers can determine an object’s distance based on how far its light has been stretched as the universe slowly expands. Astronomers can precisely measure this effect through spectroscopy, which characterizes an object’s light. But the gravitationally-lensed galaxy and other objects found at this early time period are too far away and too dim for spectroscopy, so astronomers use an object’s color to estimate its distance. The universe’s expansion reddens an object’s color in predictable ways, which scientists can measure.

Zitrin’s team performed the color-analysis technique and took advantage of the multiple images produced by the gravitational lens to independently confirm the group’s distance estimate. The astronomers measured the angular separation between the three magnified images of the galaxy in the Hubble photos. The greater the angular separation due to lensing, the farther away the object is from Earth.

To test this concept, the astronomers compared the three magnified images with the locations of several other closer, multiply-imaged background objects captured in Hubble images of Pandora’s cluster. The angular distance between the magnified images of the closer galaxies was smaller.

“These measurements imply that, given the large angular separation between the three images of our background galaxy, the object must lie very far away,” Zitrin explained. “It also matches the distance estimate we calculated, based on the color-analysis technique. So we are about 95 percent confident this object is at a remote distance, at redshift 10, a measure of the stretching of space since the big bang. The lensing takes away any doubt that this might be a heavily reddened, nearby object masquerading as a far more distant object.”

Astronomers have long debated whether such early galaxies could have provided enough radiation to warm the hydrogen that cooled soon after the big bang. This process, called reionization, is thought to have occurred 200 million to 1 billion years after the birth of the universe. Reionization made the universe transparent to light, allowing astronomers to look far back into time without running into a “fog” of cold hydrogen.

The team’s results appeared in the September online edition of The Astrophysical Journal Letters.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

For images and more information about Hubble, visit:

http://www.nasa.gov/hubble

Felicia Chou

Headquarters, Washington

202-358-0257

felicia.chou@nasa.gov

 

Donna Weaver

Space Telescope Science Institute, Baltimore, Md.

410-338-4493

dweaver@stsci.edu

Ray Villard | Eurek Alert!

More articles from Physics and Astronomy:

nachricht Major discovery in controlling quantum states of single atoms
20.02.2018 | Institute for Basic Science

nachricht Observing and controlling ultrafast processes with attosecond resolution
20.02.2018 | Technische Universität München

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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>