A week ago I posted on  Death by a Gamma Ray Burst?   This week, I focus on another space invader, a large asteroid.  PBS has had several documentaries on this topic:   The Asteroid and the Dinosaur  and   Dinosaur Apocalypse . The scientific term for the above is  Impact Event .  The biggest Earth event might have been the  Big Splash , or the Theia Impact: This when our Moon was formed approximately 4.5 billion years ago. Theia, the mythical Greek Titan, was the colliding body, mother of Selene, the goddess of the Moon. The isotope ratios of lunar and terrestrial rock are identical. There are many theories, but one is that the Moon was formed by the tangential impact upon Earth of a body the size of Mars. Much of this giant-impact consensus emerged from a 1969 conference held at Kona, Hawaii.  Those who don't believe are called the agnostics. But our solar system is today quite different, and planet-sized impact neighbors are no longer present. 2 billion years ago an asteroid cal

So what is happening today?  Nothing much of import:  National Bow Tie Day, National Cherry Turnover Day, National Red Wine Day, International Read Comics Day, National Thoughtful Day, National Bridge Remembrance Day and National Power Rangers Day.  All sanction by an organization called   National Day Calendar .  How does one get a national day?  Well, Hasbro/Saban jointly with NDC, just declared August 28 to be National Power Rangers Day.  Has thus been annually celebrated yearly since 2018.  So how do you celebrate this day?  Fans are encouraged to share memories and cosplay the Mighty Morphin Power Rangers, which premiered in 1993.  But what is National Day Calendar?  It was created in 2013 by Marlo Anderson, the so-called Guru of Geek, from his perch as podcaster of the Tech Ranch.  Must have been popular, for a million people visited his site that first year, and 10 million are expected to ping-in this year.  He said this hobby has become a major distraction to normal business ho