June 30 - Asteroid Day

Posted on June 30, 2020

Today is Asteroid Day, and tonight is also National Meteor Watch Day (in the U.S.). 


The two are somewhat related. Here's the deal:

The solar system formed from a dense cloud of gas and dust. It started collapsing, much of the gas and dust being pulled by gravity into the center. It started rotating as well. 



About 99.8% of the matter (the gas and dust) in the cloud ended up being pulled into the center and thus created the Sun. A fair amount of the leftover matter formed the eight planets and the various dwarf planets (aka Plutoids). A lot of the smaller bits became moons and rings - and a bunch of smaller-sized rubble that circles the Sun between Mars and Jupiter makes up the asteroid belt.



Asteroids, therefore, are leftovers in the formation of the solar system. They are defined as small rocky bodies that circle the Sun. (Moons and rings primarily circle planets or dwarf planets, and even though they also circle the Sun as their planet orbits our star, since their own orbit is around something other than the Sun, moons and particles that make up planetary rings are not considered asteroids.)

Asteroids range in size from dwarf planets like Ceres, which is about half the size of Pluto, down to grains of dust. Scientists' best guess of the number of asteroids is one to two million.

Meteors are any small rocky or metallic body of matter from outer space that enters the Earth's atmosphere. Most meteors burn up in our atmosphere because of the friction from running into so many air molecules . These are the beautiful streaks of light - often called shooting stars - that we are urged to look for tonight on National Meteor Watch Day.


Any meteor that is large enough to get all the way through the atmosphere and hit ground (or, more likely, ocean) is called a meteorite. 
When we talk about the theory that an asteroid hit the Earth and killed off the dinosaurs, we are talking about a really large meteor that formed a huge crater and probably mostly vaporized - causing an awful climate change event that resulted in lots and lots of species dying off.

And that is why Asteroid Day and National Meteor Watch Day are related. Asteroids can become meteors, and bits of asteroids that get hit by something can chip off and become meteors. The likelihood of a person or even a building being hit by a meteorite is surprisingly small; some sources say that there is only one confirmed case of a human being hit and (mildly) injured by a meteorite in all of history, but there is some evidence that it has happened at least a handful of times. 

But scientists say that a really large impact could have disastrous results, so we should watch for asteroids and other space debris that could become meteors!






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June 29 - National Camera Day

Posted on June 29, 2020



Now that so many humans are walking around with amazingly excellent cameras in their hand, pocket, or bag at all times, and now that so many of us can share our photos so easily and so far and so wide...

Well, our lives have changed in some amazing and scary and beautiful and important ways!

Let's think about a few of them:

Many of us enjoy "traveling" vicariously. I am super-duper unlikely to ever see China's Rainbow Mountains or Turkey's Pamukkale Terraces in person, but I love seeing photos of these amazing places!




Because so many of us have our phones-with-cameras with us at all times, we are ready to take pictures and videos of the unexpected moments of life, the teensy beauties of nature, and the adorable reactions of kids.






I mentioned that we, the people, have so many cameras ready at hand (via our cell phones), but businesses and governments also have a lot more cameras. From street cams to body cams on police, security cameras on everything from residential houses to bank ATMs to stores and corporate office buildings and and and...

So those of us who live in cities are all being filmed, all the time, and that can lead to preventing crime, finding and punishing criminals, holding accountable people who run red lights, and providing evidence about police interactions that went bad.


BUT there are also all kinds of scary things about so many cameras being trained on us. With facial recognition software and loads of street cams, security cams, all-sorts-of cams everywhere, our privacy has been eroded, and organizations that have bad intentions can much more easily target us or even frame us. Facial recognition sometimes identifies the WRONG person, and yet the supposedly objective information might persuade police and judges and juries and make innocent people face imprisonment. (And that already happens far too often!)

Not only does facial recognition sometimes identify the
WRONG person, it fails with women and people of color
way more often than it does with white men. So wrongful
arrests and other incorrect identifications are much more
likely to happen to people who already have less power
 in society - and injustices will lead to MORE injustices.
On the other hand, all of our phone cameras really, really help to capture photos and videos of those in power abusing their power. A white person who wastes taxpayer dollars and police officers' time by calling 911 because a black person is doing such nefarious activities as bird watching, barbecuing, or sleeping - well, we can film the racist harassment and use that film to protect the innocent and hopefully shame the racist. Even more important, victims and bystanders filming officers who are using too much force or actually murdering citizens has turned out to be very important to start the movement toward policing the police!

As Will Smith tweeted, racism is not getting worse, it's getting filmed!









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June 28 - Descendants Day

(Last Sunday of June)
Posted on June 28, 2020

The Tennessee House of Representatives created this special day way back on 9/11 (September 11) 1996, and it was first celebrated on the last Sunday in June in 1997.

We are all descendants, and we all have ancestors. Which of us will have descendants? 


Many family trees start with a modern person and work their way back, branching and branching as more and more ancestors and great-great-greats are added to the tree. It becomes increasingly impossible to draw all the branches, and of course it also becomes increasingly difficult to find accurate information of ancestors who lived long ago.


Some family trees are upside-down - they start with a single person from history and work their way down, down, down, through the generations, again with many branches representing all the many descendants of that original person!

One thing we should all do on Descendants Day (and every day!) is to live as if the precious land and resources were going to be passed down to our own descendants - because they will be, hopefully for generations!

We want to hand over to our descendants
a well-cared-for planet!


By the way...

Here is a very interesting video about you and me (and everybody!) being a descendant of royalty!



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