An okta is a unit of measurement used to describe cloud cover on a scale from zero to eight. Each point on the scale is then represented by divisions of a circle: an empty center for an empty sky, a completely filled circle for an overcast gray. Noah Ophoven-Baldwin’s 0 Oktas is a clear blue sky: unremarkable at first, but increasingly foreign, a series of apparently static phenomena that become…

The Beginnings of Galaxy Clusters: Proto-Clusters Finally Seen!

The deeper we peer through the cosmos, the more we are looking into the distant past.  Light from other galaxies takes millions of years to reach us, and so when that light has finally arrived at Earth, it is millions of years old, a snapshot in time of the distant galaxy.  The furthest we can see is so far back in the history of the universe, that galaxies haven’t even formed yet.  As we look at…