This month marks three years since the James Webb Space Telescope was first launched, which still feels something like a miracle given how many years of delays it took to finally get it orbiting our planet. The advanced technology onboard the spacecraft hasn't just sent back some pretty pictures, it's also challenged some of the basic tenets of cosmology, the study of some pretty big questions, including how the universe formed and how we got here.
For decades, the cosmological field was working under the assumption that, after the universe began in a hot dense soup of energy that expanded in the Big Bang, it continued to expand, forming the galaxies and stars that make up the universe. But in recent years, this understanding of how the universe expands has been put into question as two independent measurements to calculate this rate, which is called the Hubble constant, mysteriously diverged. In other words, we're trying to find out the speed limit of the expanding universe, but some measurements have given us different answers.
