Getting closer to the Edge: Knowing about just after the Beginning

 

Nearly one hundred years ago, in 1923, Edwin Hubble realised that one particular light source in the fuzzy blob called M51 (from the catalogue of fuzzy blobs identified by Charles Messier (26 June 1730 – 12 April 1817) was a Cephid variable star, and it was a very long way away. And so other galaxies were discovered. Up to then, the Milky Way was the universe. All the stars in the sky were thought to belong to the same group of stars and gas and other stuff, but now our understanding of what the universe is was utterly transformed. Hubble published his data and conclusions in 1929, and we knew then that the universe was a whole lot BIGGER. 1923: One galaxy! 2022: about 10 to the power 12 galaxies, each containing 10 to the power 12 stars. Give or take a few.This morning the story told by science is marching on again. We know more than we did yesterday. Science is provisional, and scientific knowledge is accumulating, and at certain points the new data facilitates new insights. The Hubble Space Telescope has now been surpassed by the James Webb Space Telescope, which is hiding out in the shade on the other side of our moon, gazing deep into the far distance of the observable universe. Today we are told the Deep Field picture of SMACS 0723 takes us to 13.4 billion years into the past, a past that began 13.8 billion years ago. This is a 'baby picture' of the universe, the earliest we have ever had to put in the family album. The celebrated 1995 Hubble Deep Field was of galaxies up to 12 billion light years away, so you see the great leap backwards that the Webb telescope has achieved.

For comparison, here is a central portion of the Hubble Deep Field from 1995.

I am not an expert in astronomy, and so I cannot tell you what different conclusions can be drawn from these images, taken some 27 years apart.  But for those with the expertise, the new data opens the possibility to find out new things about the distant reaches of the universe, just as Hubble found out exactly what it was that Charles Messier saw dimly through his telescope all those years before.

This is fantastic science. We have started collecting new data, and we now have information that expert astronomers can use to tell us in more detail, and with greater accuracy, what the universe was like approximately 0.4 billion years after the Beginning of our Universe. The power of scientific investigation and discovery is truly amazing. But- and this is not a bad thing- there is a limit. Science is progressing, but can only do so up to its own boundaries. Once we have collected and seen the light that there is to see from the edge of the visible universe, we won't be able to know any more. Unless there is valid evidence, possible data, then Science can't find out about it. We can only do Science if there is something to take measurements of.


There should not be a problem in pointing out that we should be modest, even about our most spectacular achievements. And this new photograph is a wondrous and spectacular achievement!


There are questions we can ask that Science can be empowered to answer. Beyond those are other questions, that future Science could come to answer. But there are already questions Science will not be able to answer. We could have some intelligent guesses, but that will be beyond Science.  We will be doing a different sort of enquiry.

1.  https://twitter.com/NASA/status/1546621144358391808?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1546621144358391808%7Ctwgr%5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fwww.telegraph.co.uk%2Fworld-news%2F2022%2F07%2F12%2Fnasa-space-pictures-telescope-james-webb-universe%2F  

2. https://lco.global/spacebook/galaxies/history-discovery/#:~:text=Other%20galaxies%20had%20been%20discovered,not%20know%20what%20they%20were.

3. https://www.nasa.gov/content/discoveries-hubbles-deep-fields