supernovae

I've read two books on this and my current favored solution to the Paradox is Supernovae and/or Gamma Ray Bursts.

The wikipedia article on near-Earth supernovae [1] suggests that Betelgeuse will be pretty safe because of its distance.

There are certain assumptions in this measurement about how Type Ia supernovae evolve over the age of the universe.

Planets composed of matter, whose heavy elements are the results of nuclear processes and subsequent supernovae.

The tightest constraints on the age of the universe come from measurements of the Hubble constant from Type Ia supernovae.

Nighttime astronomy has also had these surprises -- supernovae (leading to the discovery of dark energy), gamma ray bursts, blazars.

According to Wikipedia (thx tvmalsv!), ~10% of supernovae produce a Magnetar.

A little logic from there shows that high-redshift supernovae must accelerate away from us (the 1998 discovery that lead to the idea of dark energy).

And what processes (supernovae, stellar winds, radiation pressure, etc.) drive that?

It's thought that long GRBs originate in certain kinds of supernovae.

We discover supernovae all the time (hundreds a year), but pretty much all of those are too faint to be seen with the naked eye.

The problem with life evolving this early is that life absolutely requires the higher-mass elements from the supernovae arising from the first few stellar generations.

At some point between what's listed as "The Evolution of Low-Mass Stars" and "Supernovae" he had the class on the edge of their seats while describing how stars use up their fuel and the end results.

The early stars were enormous, burnt through their fuel (walking up the Periodic Table to Iron) and then collapsed under the gravity pressure when the fuel ran out and exploded in a Supernovae.