First Life in the Universe

[EdEarl]

 

NPR.org

I got the idea in the shower on Thanksgiving morning, while thinking about the earliest cosmic time when stars may have formed in the early universe (tens of millions of years after the Big Bang). I realized that around that time, the cosmic microwave background had roughly room temperature, which is convenient for life.

Most of the universe was the right temperature for life to exist about 10 Billion years ago, regardless of whether a planet or moon is in the Goldilocks zone, as long as it is not too close to a star that it remains too hot.

[Moontanman]

Most of the universe was the right temperature for life to exist about 10 Billion years ago, regardless of whether a planet or moon is in the Goldilocks zone, as long as it is not too close to a star that it remains too hot.

Would heavy atoms be common enough to form planets or moons?

[EdEarl]

Would heavy atoms be common enough to form planets or moons?

I've been lead to believe that very large stars were common in the early universe, and that they burn out within a few million years and go supernova to from black (gray) holes, in which heavy elements are made. Thus, rocky planets could form 10 billion years ago.

[imatfaal]

I've been lead to believe that very large stars were common in the early universe, and that they burn out within a few million years and go supernova to from black (gray) holes, in which heavy elements are made. Thus, rocky planets could form 10 billion years ago.

 

Just a quick note - it is the last moments of a star undergoing supernova that generate the elements from Iron and heavier than iron; I am pretty sure that's what you meant but your post could be read as saying that they are formed in black (grey) holes.

 

We were indeed getting Type II supernovae at around 10 billion years ago - the oldest so far discovered is from that sort of time scale

http://www.newscientist.com/article/dn17437-ancient-supernova-is-oldest-and-most-distant-found.html

Type II are the main sort that can synthesis heavier elements. I believe we have found older Type 1a (standard candles which are very useful) but which I believe are not great contributors to heavy element production (not least of which in that they are smaller mass) - although I cannot find a reference for this apart from in the dark and mouldy stack section of the library I laughably call my memory.

 

Although to go from a supernova's remnants to a new solar system has gotta take north of a billion years or so - ie everything heading outwards at almost relativistic speeds to a state where a fair amount had re-coalesced under the slow action of gravity

 

https://en.wikipedia.org/wiki/Stellar_nucleosynthesis

https://en.wikipedia.org/wiki/Supernova_nucleosynthesis

[EdEarl]

 

redorbit.com

The researchers say that the even distribution of these elements supports the theory that they were created 10 to 12 billion years ago. During this time of intense star formation, vast quantities of heavy elements were created by billions of exploding stars. During this time, black holes in the hearts of galaxies were also at their most energetic.

While the CMB temperature indicates the earliest time that life may have formed, in fact, large bodies such as asteroids, comets, moons and planets would have formed hot and cooled slower than the CMB. Thus, the temperature at which life can from would extend from the CMB temperature being right for life forming until large bodies cool too much for life to exist or water evaporates from a body. Those bodies in orbit within the Goldilocks area around stars continue to have life sustaining temperatures.

 

This observation seems to support the idea that panspermia may be the source of life on some planets; although, it is not specific evidence that Earth was seeded by life from elsewhere.