10 billion years ago, the Milky Way Galaxy was alive with new stars. It was the peak of star birth in our galaxy. Stars were being created at a rate nearly 30 times faster than today.
About 5 billion years ago, our Sun was born. The star that helped nurture all life on Earth was a late ‘boomer.’ 5 billion years ago, star formation in the Milky Way Galaxy had plunged drastically.
While the Sun wasn’t around for the big star formation party, it isn’t all bad. NASA highlights why in a press release.
The sun’s late appearance may actually have fostered the growth of our solar system’s planets. Elements heavier than hydrogen and helium were more abundant later in the star-forming boom as more massive stars ended their lives early and enriched the galaxy with material that served as the building blocks of planets and even life on Earth.
Scientists can’t look back in time in our own galaxy, but they can look deep into space at galaxies that resemble the Milky Way.
Here’s what a night sky may have looked like 10 billion years ago.
Researchers found the Milky Way-like galaxies after pouring through two catalogues with more than 24,000 galaxies. Nearly 2,000 pictures of these galaxies were gathered. Telescopes including the Hubble and Spitzer space telescopes and the Magellan Bade Telescope in Chile observed the galaxies.
“This study allows us to see what the Milky Way may have looked like in the past,” said Casey Papovich of Texas A&M University in College Station, lead author on the paper that describes the study’s results.
“It shows that these galaxies underwent a big change in the mass of its stars over the past 10 billion years, bulking up by a factor of 10, which confirms theories about their growth. And most of that stellar-mass growth happened within the first 5 billion years of their birth.”
The new study supports previous research that suggested galaxies similar to the Milky Way started as small clusters of stars.
How did a small cluster of stars explode into tons of stars?
Tremendous amounts of gas were consumed by the galaxies. This caused an explosion of star birth 10 billion years ago.
Watch this happen in the six Hubble images below.
The Milky Way has between 200 and 400 billion stars.
200 to 400 billion stars might sound like a lot, but our neighbor – the Andromeda Galaxy is believed to have one trillion stars.
At least 100 billion planets are scattered throughout our galaxy.
17 billion of these planets may be Earth-sized.
Image credit: ESO. The Milky Way Galaxy as it looks today. Second image is an artist rendering of what the Milky Way galaxy may have looked like 10 billion years ago from a hypothetical planet.