Hi science junkies! Sorry for not having too many updates. This might be a short one depending on time. Let’s get to it:
The other day, I thought to myself, “Self, I wonder how far out the farthest galaxy ever discovered is.” It turns out this galaxy candidate is pretty “far out” in both literal and figurative senses. Before we continue, I want to make a very important distinction. You notice I (will) refer to this object as a “galaxy candidate.” The reason for this is that it’s not technically proven to be a galaxy just yet. There is still more analysis to be done. In science, this is very often how it works; we find objects that we believe to be a specific type of object, and until we can prove it to be one, it stays a “candidate.” This has become very important recently, with constant discoveries of exoplanets…many of the reported findings are of candidates, not verified objects. So when you hear or read news of discoveries, always be sure to pay careful attention to this important detail!
This galaxy candidate has a very fitting, lovely name: UDFj-39546284. It just oozes awesomeness. Preliminary data shows this galaxy candidate is 13.2 billion years away (for those of you who know something about astronomy, that’s a redshift of 10.3). The fact that this object is so far away does not mean it is really old…it actually means it’s really young! Remember that the light we see coming from this galaxy candidate was emitted 13.2 billion years ago…we’re seeing it as it was a mere 500 million years after the big bang!
500 million years sounds like a long time, but I’ll give you some perspective: if the Universe was a 100 year old man, we’re seeing this galaxy as it was when the Universe was 4 years old! So while the galaxy candidate is so far away, it’s actually really young…or rather, we’re seeing it as it was when it was in its infancy. This is why to study galaxies, we have to look at different distances…this allows us to see galaxies at different stages in their lifetimes. Below is a picture of this galaxy candidate, in the infrared:
Photo credit to: NASA, ESA, Garth Illingworth (University of California, Santa Cruz) and Rychard Bouwens (University of California, Santa Cruz and Leiden University) and the HUDF09 Team.
Hopefully, with the launch of JWST (It’ll get launched eventually, we promise!), we’ll see even farther than Hubble, to a redshift of 20 or greater! (that’s 13.5 billion years back in time!) Fascinating, the things that are still to be discovered!