The Hubble Space Telescope may have discovered the farthest-away object ever identified, a galaxy with light that began shining when the universe was only about 500 million years old.
The galaxy was born at a time of rapid acceleration in the birth rate of stars, according to the study released today by the journal Nature. The observation needs to be confirmed with spectroscopy, an analysis of light that shows the temperature, mass, luminosity and composition of an object.
The Big Bang that scientists believe began the universe occurred an estimated 13.7 billion years ago. Another early galaxy, created about 600 million years after the universe was formed, was discovered in October, also identified using Hubble. Finding early space objects created immediately following the Big Bang can provide clues as to how the universe was formed.
The Hubble, run by NASA, is a space-based telescope that was carried into orbit by a space shuttle in 1990, according to the National Aeronautics and Space Administration website. Astronauts repaired and upgraded the school-bus-sized Hubble in 2009 to extend its life.
Today’s data come from a small area of the sky known as the Hubble Ultra Deep Field, which were detected using the Wide Field Camera 3. This upgrade, installed in 2009, has the potential to be 35 times better at infrared than the Advanced Camera for Surveys, installed at the telescope in March 2002.
Confirmation from the James Webb Space Telescope is needed to ascertain this object is a galaxy. That telescope is scheduled to be launched in 2014 to replace the Hubble and see deeper into the universe’s past.
Finding far-away galaxies is difficult because their once- bright light falls into the infrared part of the spectrum, which isn’t visible to the naked eye.
After the Big Bang, the universe expanded and cooled, losing enough heat so that protons and electrons combined to form hydrogen, a relatively opaque gas which consists of a single proton orbited by a single electron. At some point, some electrons split off, ionizing the hydrogen and making it relatively clear, allowing people on earth to gaze at the stars.
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