The Hubble and Spitzer Space Telescope’s have discovered the oldest known galaxy formed about 700 million years after the big bang. The galaxy is named A1689-zD1 and was imaged by Hubble’s Near Infrared Camera and Multi-Object Spectrometer. Spitzer’s Infrared Array Camera provided additional evidence of the galaxy’s age, estimated at 12.8 billion years.

It’s interesting to find a galaxy of this age because even though it may be 12.8 billion years old, the light we are now receiving is from the time when the galaxy was young and just forming, giving us a glimpse into galaxy formation early in the development of the universe. Who knows, the galaxy may have burned out a long time ago or collided with another galaxy. We don’t have that information yet. The speed of light is fast at 186,282 miles per second, but the distances are so vast; it still took 12.8 billion years for the light to reach us. So we are seeing the galaxy as it was a very long time ago.

Scientists theorize the universe became a cold cloud of hydrogen 400,000 years after the big bang. Probably due to gravitational effects, stars and galaxies began to form from this cloud creating heat and further moving along the development of stars and galaxies.

Since A1689-zD1 is so far away, the Doppler effect stretched its light to the invisible infrared wavelengths requiring special infrared cameras to detect it with the aid of an effect called gravitational lensing. In this case, a nearby large cluster of galaxies, Abell 1689, bent the light coming from A1689-zD1 and magnified it by a factor of ten. A signature smearing of images from A1689-zD1 around Abell 1689 into arcs of light helps confirm the effect. Abell 1689 acts like a magnifying glass due to its strong gravity by bending light coming near it like a cosmological zoom lens.

Due to the distances involved, direct observation of light from A1689-zD1 is not possible without an intermediary like Abell 1689 providing a “boost”. The galaxy appears as something smaller than our Milky Way, spanning a width of only 2,000 light years. The complete results will be published in the Astrophysical Journal.

A massive cluster of yellowish galaxies is seemingly caught in a spiders web of eerily distorted background galaxies in the left-hand image taken with the Advanced Camera for Surveys aboard NASAESA Hubble Space Telescope. The gravity of the clusters  ...NASA/Hubble photo

Inside the small white box above, half-way down and two-thirds of the way over, lies the galaxy A1689-zD1.

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