The Hubble Space Telescope (HST) was launched into low Earth orbit roughly 25 years ago to allow scientists and astronomers to peer into space. Since that day, Hubble – the largest and most versatile space telescope – has recorded some of the most detailed and awe-inspiring images, which have led to several breakthroughs in astrophysics.
In line with its already established reputation, Hubble, along with the Herschel space telescope, was recently used to peer back in time in order to provide astronomers with an idea of how galaxies have undergone dramatic metamorphic transformations over the last eight billion years or so. The study, lead by Steve Eales, a professor at Cardiff University, was recently published in the Monthly Notices of the Royal Astronomical Society.
What The Hubble Space Telescope Tells Us About the Universe
According to Discovery News, an international team of researchers, studying data from 10,000 observable galaxies, found that 83 percent of stars, formed since the Big Bang, were originally grouped in “flat, rotating, disc-shaped galaxies” like our Milky Way.
Today, however, only 49 percent of stars that exist in the Universe are located within these so called “disc-shaped galaxies.” The rest exist in a second classification of galaxies, characterized by an oval or spherical shape.
HOW DID METAMORPHOSIS THIS HAPPEN?
To explain the change, scientists have come up with two possible hypotheses. The first attributes the transformation to a merging event, in which two disc-shaped clusters move too close to each other due to gravity. The second explanation suggests that stars in a “round, flat galaxy,” migrate towards the core to produce the spherical shape.
This galactic “shape-shifting,” as Discovery News states, has been theorized before. However, the space telescopes, combined with previous years of data, have provided a clearer understanding of the process.
“Galaxies are the basic building blocks of the Universe, so this metamorphosis really does represent one of the most significant changes in its appearance and properties in the last eight billion years,” stated Eales.
