The pixels of the James Webb Space Telescope's first image just released today, that are the least interesting to the public, will be the most instructive to astronomy and astrophysics. The tinest faintest dot you see is a distant billions of years old galaxy. If an ordinary picture is worth 1000 words when that picture is of a ordinary looking scene here on a single planet, then every pixel of this image from the James Webb Space Telescope will be worth 1000 x1000 words. Without careful analysis of each pixel there is not much that can be said scientifically right off the bat. Not more than the description NASA themselves give.
“The image shows the galaxy cluster SMACS 0723 as it appeared 4.6 billion years ago. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying much more distant galaxies behind it.” That’s what NASA says. To my eye I see a few more details. There are very noticeable objects with diffraction peaks around them. Those are most likely to be foreground stars. Though without knowing distances to each of those I can’t rule out some distant quasars are among the smaller, fainter “star like” points of light one sees when zooming in.
The red streaks you see are images of distant galaxies created by the gravitational lensing due to the mass of the galaxy cluster.
The dimmest, smudges of light in the background are the most distant galaxies seen to date and seen at better angular resolution (In angular resolution smaller is better). It is from analysis of those pixels we will learn about the early, post Big Bang universe. Every bit of this data will be subjected to deep numerical analyses.
A question that interest me and probably has an answer in the literature somewhere is just what is going on with these galaxies? Are they colliding?
Is one just close to the other in our field of view BUT they are separated by a Billion light years? I can't say at a glance. Looks a lot like a collision but looks can be deceiving without knowing distances which we could determine by redshift.
Comments