In class, we read a Scientific American article, "Cloudy with a Chance of Stars" that explained how the cores and the dust around them formed stars(he called them eggs for a chicken/egg analogy, where cores are eggs and I suppose novae are the chickens because the novae cause the core to start to collapse), but we don't know how the very first stars were actually formed.

What are the leading hypotheses in this area, or am I misinterpreting the article? If you have a Scientific American account, here's the article I am referring to.

  • $\begingroup$ If the Universe began with the Big Bang, the matter rapidly formed hydrogen atoms, that attracted each other by gravity. With some time, the matter would be unevenly distributed, forming bodies that would later light up (because the weight of the outer atoms would cause the fusion of the inner atoms). $\endgroup$
    – Rodrigo
    Mar 13, 2017 at 3:38
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    $\begingroup$ Rcteg - worthwhile reading the links in the Related sidebar to the right $\endgroup$
    – Rory Alsop
    Mar 13, 2017 at 11:28
  • $\begingroup$ I'll link two articles. The first suggests that the very first stars were massive. It's not too hard to imagine that sufficient gravity could collapse a gas cloud of hydrogen and helium into a star if there was enough mass in a small enough region to start spiraling and collapsing. scientificamerican.com/article/the-first-stars-in-the-un The 2nd article indicates some remaining uncertainty on early formation with so little heavier elements. universetoday.com/10050/how-did-the-first-stars-form consider this a starting point, not an answer. $\endgroup$
    – userLTK
    Mar 14, 2017 at 0:33
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    $\begingroup$ Your (or the author of the article's) main problem appears to be thinking that supernovae (not novae) are necessary for star formation. They aren't. Gas clouds collapse to form stars without help. $\endgroup$
    – ProfRob
    Aug 8, 2017 at 7:31

2 Answers 2


It is a question of where, but also to better understand, you must know when it happened. Because earls structure was different from today's.

From wiki on Universe's chronology,

CMB Timeline300 no WMAP.jpg
By NASA/WMAP Science Team - Original version: NASA; modified by Ryan Kaldari, Public Domain, Link

you will learn that first stars are thought to appear when the Universe is about 3% of its current age, i.e. 400 million years old. This is the time it took for first atoms to cool down sufficiently and gather together in the clouds in question.

To see where first star formation happened, we have the possibility to look back in time.

  • we can see the star being born, and for this we need to use radio frequencies, because infrared was the only thing coming trough the surrounding gas clouds, from that time is so red shifted...
  • if we are very lucky, we can see these stars exploding - since they are so big, they will quickly come to an end and explode - but because of surrounding gas clouds it is regarded as a rare event.
  • there are simulation tentative like this one where we use currently know physic laws to calculate the evolution of matter since it first emitted light (CMB - the bluish-greenish thing on above image); the very small differences in this primordial light we are able to see allow the simulation to explain densities differences and the apparition of filaments, planes and clusters (nodes at the intersection of planes and filaments). These things can be artistic, as you can see here filaments and a Protogalaxy simulated:

Filament and cluster simulated Protogalaxy simulated from Sky & Telescope

Clusters where the denser places of the universe, and due to this highest matter density, is where first stars where created.

  • Here is an images where it is thought a filament is actually seen, lightened by a catastrophic event it hosts:

indirect filament observation

The Lyman-alpha blob (blue fuzz) surrounding the quasar UM 287 (white dot in center) extends 1.5 million light-years long, far too big to be contained within the quasar's host galaxy or the host galaxy's halo. The blue fuzz is likely to be part of a cosmic web filament.

S. Cantalupo / UCSC

I invite you to get a better idea of what we can see of the distribution of stars from our planet here, where you can zoom in and out and get an understanding of scales.


The universe began with a Big Bang, which supplied the universe with huge amounts of matter in the form of free quarks and electrons. After the universe had expanded for a bit, it cooled enough for simple atoms like hydrogen-1 and helium-4 . This time was known as 'the dark ages' because light could not easily penetrate the matter, and besides, there were not any stars to create light.

However, the matter created at the beginning of the dark ages was not evenly distributed. The regions with slightly more matter ended up attracting, through gravity, more and more matter to the protostar. The matter eventually condensed to a critical density, where fusion begins. This seems to be the leading hypothesis as I searched through several sources, including The Formation of the First Stars and Galaxies and The First Stars in the Universe - Yale Astronomy.

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    $\begingroup$ This doesn't really answer the question of what the leading hypotheses on the formation of first stars are. $\endgroup$
    – xzackli
    Aug 7, 2017 at 19:54

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