Tip:
Highlight text to annotate it
X
[ music ]
A Telescope Bigger than a Galaxy -
presented by Science@NASA
More than 400 years ago,
Galileo turned a primitive spyglass toward the sky,
and in just a few nights
learned more about the universe of unseen things
than all of the scientists
and philosophers before him, combined.
Since then astronomers have been guided by a simple imperative:
Make Bigger Telescopes.
As the 21st century unfolds,
the power of optics has grown a million-fold.
Telescopes cap the highest mountains,
sprawl across deserts,
fill valleys and even fly through space.
These modern giants
provide crystal-clear views of stars and galaxies
billions of light years farther away
than anything Galileo ever saw,
each breakthrough in size
bringing a new and deeper understanding of the cosmos.
It makes you wonder,
how big can a telescope get?
Would you believe,
bigger than an entire galaxy?
At the January 2014 meeting of the American Astronomical Society,
researchers revealed a patch of sky
seen through a lens more than 500,000 light years wide.
The 'lens' is actually a massive cluster of galaxies
known as Abell 2744.
As predicted by Einstein's Theory of General Relativity,
the mass of the cluster
warps the fabric of space around it.
Starlight passing by is bent
and images are magnified,
much like an ordinary lens
except on a vastly larger scale.
Lately, the Hubble Space Telescope,
along with the Spitzer Space Telescope
and the Chandra X-ray Observatory,
has been looking through this gravitational lens
as part of a program called 'Frontier Fields.'
'Frontier Fields aims to explore the first billion years
of the Universe's history,'
says Matt Mountain
from the Space Telescope Science Institute
in Baltimore, Maryland.
The question is,
'Can we use Hubble's exquisite image quality
and Einstein's theory of general relativity
to search for the first galaxies?'
The answer seems to be 'yes.'
At the AAS meeting,
an international team
led by astronomers from the Instituto de Astrofisica de Canarias
and La Laguna University
discussed Hubble and Spitzer observations
of the Abell 2744 cluster.
Among the results was the discovery
of one of the most distant galaxies ever seen-
a star system 30 times smaller
yet 10 times more active than our own Milky Way.
Bursting with newborn stars,
the firebrand is giving astronomers a rare glimpse
of a galaxy born not long after the Big *** itself.
Overall, the Hubble exposure of Abell 2744
revealed almost 3,000 distant galaxies
magnified as much as 10 to 20 times brighter
than they would normally appear.
Without the boost of gravitational lensing,
almost all of those background galaxies
would be invisible.
Abell 2744 is just the beginning.
The Frontier Fields program
is targeting six galaxy clusters
as gravitational lenses.
Together, they form an array of mighty telescopes
capable of probing the heavens as never before.
Galileo, eat your heart out.
For more news from Frontier Fields
and the edge of the Universe,
stay tuned to science.nasa.gov