First Galaxy

This is interesting because it sheds some light on how the universe we see today actually formed. A team of astronomers using the Large Millimeter Telescope (LMT) in Mexico's Instituto Nacional de Astrofisica, Optica y Electronica, found one of the very first galaxies. They believe that it formed within the first one billion years after the Big Bang.

The Big Bang occurred 13.8 billion years ago and for the first 400 million years the universe was too uniform to form anything. So, this galaxy formed within the period between 500 million to 1 billion years after the Big Bang. This means that the first objects, large stars, galaxies and black holes formed during this period. This was only a theory until this momentous discovery.

The LTM is the only way to discover these distant objects. It's situated on a 15,000-foot extinct volcano in Mexico and consists of a 32-meter millimeter-wavelength radio telescope, making it most sensitive instrument of its kind, especially after it's expanded to 50-meters.

Why do they need to use a millimeter radio telescope to see these ancient and distant objects? The reason is redshift. As the universe expands, the light from these distant objects is shifted into the red end of the spectra and as far as the radio spectrum. It's virtually impossible to detect them in visible light.

The reason the millimeter wavelength is used is because of the spectral line of carbon monoxide. The red-shifted spectral peak for this material is shifted out into the radio spectrum by cosmic expansion. One thing that helps in this observation is the fact that radio waves pass through dust, whereas visible light is blocked or absorbed.

A sub-millimeter telescope on Mauna Kea, Hawaii also verified this distant early galaxy's existence. The triangulation helped improve the image. Another thing that helped was gravitational lensing by a large galaxy in-between the distant galaxy and Earth. This increased the brightness of the object.

What's important about this find is that there could be many more of these very early galaxies out there. Finding them would help astronomers and cosmologists understand more about how the universe actually formed.

Thanks for reading.