I posted This a little while ago about a lecture I’d attended at Space Telescope on the nature of the first stars.  Folks I talked to afterward indicated that while the upcoming James Webb space Telescope might, just might, be able to see their explosive ends, it would be only by pure unreasonable luck.  They are just too far back in time, too red shifted, too distant and faint for anything we have in the works for the next twenty years or so.

But from this New York Times article, it looks as though maybe, just maybe, they’ve already been spotted.  Accidentally…just like the cosmic background noise was first spotted…

Theory Ties Radio Signal to Universe’s First Stars

When the universe was still young, they were already dying.

The first stars ever to grace the cosmos with light were brutish monsters, so the story believed by most astronomers goes, lumbering clouds of hydrogen and helium hundreds of times more massive than the Sun. They lived fast and bright and died hard, exploding or collapsing into massive black holes less than a billion years after the Big Bang, never to be seen again.

But they might have left something behind, a buzz of radio waves emitted by high-energy particles spit from the doomed gas swirling around those black holes.

They were looking at the cosmic background radiation at wavelengths not previously studied in detail.  What they saw were large magnetic whirls that were so energetic they’d be expected to come from the so-called radio galaxies…that is…galaxies that are very energetic in the radio frequencies due to the active and massive black holes in their center.  Active because they are still sucking in nearby matter.  You don’t generally see these galaxies in the visible light spectrum much, if at all, because they are so far away they’re red shifted.  But in the infrared, and in the radio spectrum there they are, bright as can be.  Hence they are referred to as radio galaxies.

But if these signals were coming from radio galaxies, then there should also be an equally strong infrared signal to go along with them, from the heat generated in their massive accretion disks.  But there is not much of a signal there.  There should be much more.  But that’s assuming the signal is coming from a massive center of a galaxy black hole. 

Even the first galaxies would have already had lots of recycled matter in them…matter that had already gone once or more though stars, and was seeded with heavier elements then hydrogen and helium in the process.  But if the black holes at the center of these accretion disks were surrounded by nothing but hydrogen and a little helium, and perhaps only a trace of heavier elements, then the infrared signal would be a lot weaker.  The only way that could be happening, is if the black hole in question is the ash from a first star. 

All the first stars had to burn with were the original hydrogen and helium left over from the big bang.  There was nothing else on the menu for stars in the newly born universe.  The first super-massive black holes would have lived in the same environment, as the heavier elements created by their star would have been blown far away in its final collapse.  So it’s possible that what they are seeing now, while not the light from the first stars, is the footprints they left behind. 

I have wondered for years now which comes first, the galaxy or the massive black hole in its center.  My layman’s hunch for a while now is that the black hole is the seed that starts it all.  But where do the first super massive black holes come from?  When I heard the story of the first stars I thought I had an idea where.  And then it came to me that the importance of the first stars isn’t that they started the process of generating the heavier elements, but that they generated the first black holes which were the seeds around which the galaxies could form.  Without those first super-massive black holes I don’t think you could get the galaxies as we see them now.  Maybe you’d get the kind of stars we see now, but a lot fewer of them and scattered around in a clusters and swarms in the darkness maybe.  But that’s just a layman’s guess, basically.