Until a century ago, astronomers were certain that our galaxy is the only one from the entire Cosmos. But Edwin Hubble changed that, discovering that there are billions of other galaxies. Nowadays, scientists are sure that there are at least trillions of galaxies in the observable Universe. Also, science is almost sure that many other universes exist, and who knows what we could find in them.
Thus, it’s pretty important to know a little history about our own galaxy, and this implies to have idea of when it all began.
10 billion years-old is the new number
38 scientists worked very hard to find new insights for the age of our own Milky Way galaxy. They have been led by researchers from the ARC Centre of Excellence in Australia for All Sky Astrophysics in Three Dimensions (which is dubbed ASTRO-3D). They all together used data gathered by NASA’s Kepler space telescope, and concluded that our galaxy is about 10 billion years old.
Dr. Sanjib Sharma, the lead author of the study, says that the new conclusion clears out a mystery. He continues by saying:
Earlier data about the age distribution of stars in the disk didn’t agree with the models constructed to describe it, but no one knew where the error lay – in the data or the models. Now we’re pretty sure we’ve found it.
Milky Way is a typical galaxy
Our Milky Way galaxy is one of the many other spiral galaxies out there. But it’s not so typical if you consider that it’s the only galaxy that hosts life, as far as we know until now. It could be described in two parts, two disks: a thick and a thin one. The thicker one contains around 20 percent of the total number of stars, and it’s older than the other disk.
The new findings have been published in the journal Monthly Notices of the Royal Astronomical Society.