
Using the Very Large Array of the National
Radio Astronomy Observatory in the US, the
team observed radio emission from hydrogen in
a distant galaxy and found that it would have
contained billions of young, massive stars
surrounded by clouds of hydrogen gas.
As the most abundant element in the Universe
and the raw fuel for creating stars, hydrogen is
used by radio astronomers to detect and
understand the makeup of other galaxies.
However, until now, radio telescopes have only
been able to detect the emission signature of
hydrogen from relatively nearby galaxies.
"Due to the upgrade of the Very Large Array,
this is the first time we've been able to directly
measure atomic hydrogen in a galaxy this far
from Earth," lead author, Dr Ximena Fernández
from Rutgers, the State University of New
Jersey, said.
"These signals would have begun their journey
before our planet even existed, and after five
billion years of travelling through space without
hitting anything, they've fallen into the
telescope and allowed us to see this distant
galaxy for the very first time."

Artist's impression of the gas cloud and galaxy.
Credit: ICRAR/Peter Ryan
As an archaeologist digs down they find older
and older objects. The same is true for
astronomers—as they build bigger telescopes
and develop new techniques to see farther into
the Universe, they look further and further back
in time.
"This is precisely the goal of the project, to
study how gas in galaxies has changed through
history," Dr Fernández said.
"A question we hope to answer is whether
galaxies in the past had more gas being turned
into stars than galaxies today. Our record
breaking find is a galaxy with an unusually large
amount of hydrogen."
This success for the team comes after the first
178 hours of observing time with the Karl G.
Jansky Very Large Array (VLA) radio telescope
for a new survey of the sky called the 'COSMOS
HI Large Extragalactic Survey', or CHILES for
short.
Once it's completed the CHILES survey will
have collected data from more than 1,000 hours
of observing time.

Artist's impression of the galaxy. Credit: ICRAR/
Peter Ryan
In a new approach, members of the team
including Dr Attila Popping from International
Centre for Radio Astronomy Research and the
ARC Centre of All-sky Astrophysics (CAASTRO)
in Australia are working with Amazon Web
Services to process and move the large
volumes of data via the 'cloud'.
Comments