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The Cosmology Portal
The Hubble eXtreme Deep Field (XDF) was completed in September 2012 and shows the farthest galaxies ever photographed. Except for the few stars in the foreground (which are bright and easily recognizable because only they have diffraction spikes), every speck of light in the photo is an individual galaxy, some of them as old as 13.2 billion years; the observable universe is estimated to contain more than 2 trillion galaxies.
... that space is flexible, and has been expanding at a measurable rate since the beginning of time?
... that most of the atoms in our bodies were created in stars through fusion?
... that the Earth isn't flat, but the universe is? Based on Einstein’s Theory of General Relativity, there are three possible shapes that the Universe may take: open, closed, and flat. Once again, measurements by WMAP on the CMBR have revealed a monumental confirmation – the Universe is flat.
... that the average density of visible matter in the universe is about 10−30 g/cm3?
... that the Earth is neither the center of the Universe nor the galaxy, because the universe has no center?
... that considering only the largest structures, the Universe is made up of filaments, voids, superclusters, galaxy groups and clusters? By combining galaxy groups and clusters, we come up with superclusters. Some superclusters in turn form part of walls, which are also parts of filaments.
Hubble provided evidence that the recessional velocity of a galaxy increases with its distance from the earth, a property now known as "Hubble's law", despite the fact that it had been both proposed and demonstrated observationally two years earlier by Georges Lemaître. Hubble's Law implies that the universe is expanding. A decade before, the American astronomer Vesto Slipher had provided the first evidence that the light from many of these nebulae was strongly red-shifted, indicative of high recession velocities.