Turns out that the Sun took a little longer to show up than many of the other stars that fill up the Milky Way. This might not be such a bad thing after all. Data suggests that the majority of stars were formed during a “baby boom” approximately 10 million years ago, yet the Sun did not develop until 5 billion years ago. The study is published in the Astrophysics Journal by a team from Texas A&M University, led by Casey Papovich. It has led to a surprising reevaluation of the Sun’s place in the galaxy and how we are lucky that it came later than it should have.
Observations of the Milky Way
Using both the Hubble Space Telescope and ground based observations, the team went looking for galaxies similar to the Milky Way at various distances all over the universe. Because light takes time to travel, the further away a galaxy is, the further back in time we are actually viewing that galaxy. If you look a billion light years away from Earth, you actually looking many billions of years back into time.
The task was to wade through a possible 24,000 galaxies before whittling the number down to 2,000. By compiling all the data on different galaxies at different time periods, the team was able to determine that a buildup of stars typically happens in the first 5 billion years and that they experienced a period of intensely rapid star formation, at a rate that was nearly thirty times what it currently is estimated at.
So how did we benefit? Well there was more of the heavy elements floating around after the previous stars had formed – and occasionally exploded. This meant that when the Sun developed a bit later, it was surrounded by the kinds of material that are great for building planets. The study also gives up a better understanding of how the Milky Way is likely to continue evolving. In a press release, Papovich noted that there was a correlation between the rate at which new stars were forming and the size of the galaxy. You can view the technical abstract of the full article here, on the Astrophysics Journal website.
For glimpses into the vast wonders of space, check out the Northern Lights in Iceland.