Cobalt

In my last post, I wrote about insulin and interesting features of the insulin structure.  Some of the things I learned were really surprising.  For example, I was surprised to learn how similar pig and human insulin are.  I hadn't considered this before, but this made me wonder about the human insulin we used to give to one of our cats.  How do cat and human insulin compare? It turns out, that all vertebrates produce insulin, even frogs and zebra fish.  Human preproinsulin is only 110 amino acids long and even human and fish insulin are pretty similar.  Of course, this observation only leads…

What's going to happen to all the stars in the Universe as they get older? Well, just as nothing can live forever, stars can't live forever also. Why? Because they run on fuel: burning hydrogen into helium, for example. When they run out of fuel, something's gotta give. Barbara Ryden reminds us of an excellent and appropriate quote by Dylan Thomas: Do not go gentle into that good night. Rage, rage against the dying of the light. But what exactly happens to the star depends very sensitively on what the mass of the star is. If you've got a tiny little star, less than about 40% of the mass of…