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Frontier Fields

Celestial Tour: Frontier Fields—Peering ever Deeper into the Universe

Hubble was aimed at a small, unremarkable patch of sky and left the telescope pointed there for 10 days. The results were amazing.

Frontier Fields
Produced by the Space Telescope Science Institute’s Office of Public Outreach in collaboration with NASA’s Universe of Learning partners: Caltech/IPAC, Center for Astrophysics | Harvard & Smithsonian, NASA Jet Propulsion Laboratory, and Sonoma State University 
All images, illustrations, and videos courtesy of NASA except:
  • Gravitational lensing animations courtesy of G. Bacon & F. Summers (STScI) and NASA, ESA & L. Calçada
  •  Taurus constellation drawing from Firmamentum Sobiescianum sive Uranographia by Johannes Hevelius, courtesy of the United States Naval Observatory
  • Hubble orbit animation courtesy of G. Bacon (STScI)
  • Hubble Space Telescope slewing animation courtesy of ESA/Hubble (M. Kornmesser & L. L. Christensen)
  •  Simulation of a lens passing over the Hubble Deep Field courtesy of ESA/Hubble (M. Kornmesser & L. L. Christensen)
  • Background star field courtesy of A. Feild (STScI)
  • Frontier Fields background star field images courtesy of the Digitized Sky Survey
  • Chandra spacecraft illustration courtesy of Northrop Grumman Corporation
  • Animation of the Hubble Space Telescope flying over Earth courtesy of ESA/Hubble (M. Kornmesser)
  • Written by Vanessa Thomas
  • Designed by Marc Lussier 
  • Music courtesy of Associated Production Music


 Title, Frontier Fields, Peering Ever Deeper Into the Universe. 

Reflective silver tube-shaped telescope with paneled wings flies through space. 

Text, In 1995, the Hubble Space Telescope opened a new window on the universe. 

Animation shows Hubble circulating around Planet Earth as it creates a shape at its axis point. 

Astronomers aimed Hubble at a small, unremarkable patch of sky and left the telescope pointed there for 10 days. 

Shape enlarges to show tiny colorful specks against blackness of space. 

Text, H.D.F., Hubble Deep Field. The results were amazing. 

Thousands of galaxies had appeared in that, quote, empty, unquote, bit of sky. 

Years later, after new cameras were installed on Hubble, astronomers ran the experiment again. 

H.U.D.F., Hubble Ultra Deep Field. The Hubble Ultra Deep Field revealed even more galaxies -- and more-distant galaxies. 

Two rectangles pop out to show close-up views of H.U.D.F., Red spots in space circled in green. 

Text, Galaxies about 13 billion light-years away. 

Dark view of H.U.D.F. becomes brighter to reveal more colorful specks, Text, Infrared light. 

Observations in infrared light pushed the boundaries even farther, turning up galaxies even more remote. 

One red spot circled in green. Text, Galaxy about 13.2 billion light-years away. 

Hubble's deep fields were astounding, and they inspired new questions. 

Does the whole universe look like the deep fields? 

Rectangles of colorful specks in space fill screen, outlines of rectangles disappear to create one large image. 

Text, And could Hubble see any farther into the universe than this? 

Silver Hubble telescope rotates in space with reflective mirror object at its end. 

Text, Astronomers came up with an idea to try to find out. 

Objects in space glow of orange blue and red colors. 

Text, They could use nature's telescopes -- galaxy clusters. 

Diagram shows lines which reach out from a galaxy to Earth, lines labeled light rays. 

Text, As light from a very distant galaxy passes through a galaxy cluster, the light gets bent and magnified by the cluster's enormous gravitational field, as if the cluster were a giant lens. 

On diagram between galaxy and Earth, a group of glowing balls appears labeled galaxy cluster. Light rays bend, Text, distorted light rays. 

Without this gravitational lensing effect, it would be impossible to see the distant galaxy behind the cluster. 

Two small specks circled in yellow labeled lensed galaxy images. 

Astronomers have picked out six galaxy clusters that act as excellent gravitational lenses. 

Six areas squared off filled with multi-colored specks in the sky. 

Text, Frontier Fields. As part of a three-year project called the Frontier Fields, Hubble stared at these six clusters. 

It looked for faraway galaxies no one had seen before, some possibly farther than any other found before. 

On one image of a starry sky, a blue square labeled Visible. Inside that blue square is a red square labeled Infrared. 

Text, Hubble studied these clusters not just in visible light but in infrared light as well. 

Several glowing spiral shapes laid on a grid. 

Because the universe's expansion stretches visible light into infrared light, the most distant galaxies can only be spotted in the infrared. 

Squiggly line connects one galaxy to another, with peaks in the line spaced farther apart the more distant it becomes. 

Text, Aided by the gravitational lenses, Hubble's infrared camera picked out some of these extremely remote galaxies. 

Squared-off section of space circles three red dots in green. 

As one of Hubble's cameras concentrated on each galaxy cluster, another camera peered at a relatively empty region of sky located nearby. 

An area squared-off labeled parallel field near a galaxy cluster. 

Six separate views of galaxy clusters with parallel fields nearby. 

Text, These six parallel fields, one for each of the six galaxy clusters, gave us six brand new deep fields. 

These new deep fields show us how other parts of the sky contain the rich chorus of galaxies that fills Hubble's earlier deep fields. 

Hubble telescope as it flies through space with Earth in background. 

Text, During its three-year observing program, the collaborative Frontier Fields project pushed the frontiers of what we can learn about the faraway universe with the Hubble Space Telescope, before the James Webb Space Telescope takes its own place in space and pushes the boundaries even further. 

James Webb Telescope, golden reflective surface of hexagonal shapes sits on kite-shaped silver base.