January 31 – A White Dwarf Is Discovered!

Posted on January 31, 2016



When I say white dwarf, I am not talking about a Little Person. Instead, I am talking about a certain kind of star.

Or, rather, I am talking about a certain part in the life cycle of some stars.

Sirius is the brightest star in the Earth's night sky. As a matter of fact, it is almost twice as bright as the next brightest star, Canopus. Naturally, it was seen by the earliest humans (and their not-yet-human ancestors), and later by ancient humans, and later still by medieval and then Renaissance humans...all the way up til now – BUT on this date in 1862, an American astronomer named Alvan Graham Clark spotted something nobody else had ever seen before:

Sirius has a much dimmer companion star!

So now, the thing we called Sirius pre-1862 now has to be called the Sirius star system, and we call the two different stars that make up that system Sirius A and Sirius B.

The Sirius star system seems bright in Earth's sky partly because it is pretty close – and getting closer! For the next 60 thousand years, Sirius will seem to get slightly brighter and brighter and brighter (after that, the distance between star systems will start to widen again, but Sirius will still be the brightest star in our sky for another couple of hundred thousand years!).

But the other reason Sirius seems so bright is because Sirius A is seriously large and seriously bright. It is about twice as massive as the Sun, and it is 25 times more luminous than the Sun. (There are stars in the universe even more massive and even more luminous than Sirius A, but they are farther away. Likewise, there are some stars that are closer, but they aren't as big and bright.)

What about Sirius B? It is much smaller than Sirius A, which is why it is called a dwarf; it is only about the size—or volume—of Earth, although it has almost as much stuff—mass—as the Sun! You have probably already guessed that Sirius B is much less luminous than Sirius A, as well – so faint that it took scientists a long time to spot it next to its brighter companion.

According to Wikipedia, Sirius B is a whopping ten thousand times less luminous than Sirius A, in visible light (although it does emit more X-rays than its companion). 

It wasn't always so. Millions and millions of years ago, both Sirius A and Sirius B were huge blue stars, burning hot and bright. Sirius B happened to be the more massive one, so it burned up its hydrogen more quickly, fusing it into helium at a much quicker rate. Once the fuel ran out, the star sort of imploded, collapsing in on itself. Once that happened, things heated up so much that helium was able to start fusing into carbon and oxygen. At that point, about 120 million years ago, Sirius B ballooned out to become a red giant. The more the star expanded, the less gravitational attraction the outer layers of the star had for the inner core, and those layers drifted away. Eventually, all that was left of Sirius B was that inner core, which is what we see. It is a very dense, very hot body is not undergoing fusion anymore. It will slowly cool off more and more and more, until it becomes a black dwarf.

This is all part of the normal life cycle of average stars, including our sun and even Sirius B.


 

  • Here is a zoom to see Sirius B next to its much larger companion. 




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January 30 – Happy Birthday, Lloyd Alexander

Posted on January 30, 2016

Here are some of my favorite friends from my childhood: Taran, Eilonwy, and Gurgi. Here are some of my kids' favorite friends, from their childhood: Taran, Eilonwy, and Gurgi.

I'm sure you realize that when I say friends, I really mean “friends” with quotation marks. Really, they were beloved characters from oft-read, much-loved books.

And therein lies the beauty of books – new generations can enjoy wonderful characters and engaging plots just as much as their parents and maybe even grandparents before them did!

Getting back to Taran, Eilonwy, and Gurgi: 

Taran was a wanderer; a boy who had no station in life, no known parents; a boy who really wanted to be a hero. 

Eilonwy was a princess with a non-stop tongue, a handy bauble that serves as a flashlight (among other things), and a stick-up-for-herself attitude. 

Gurgi was...well, nobody really knew what Gurgi was. He wasn't quite human, but he could talk, after a fashion. He was mussy and hairy and always hungry – “crunchings and munchings” were big in his life (and in my family's discussion of snacks as well)!



These three are some of the characters of the five-book Chronicles of Prydain. They were written by today's birthday. Lloyd Alexander, in the 1960s, and two of the five were honored with a Newbery Honor and a Newbery Medal. An honor that is even harder to get is a Disney movie; in 1985, Disney released a Prydain animated movie that wasn't very like the books (and wasn't, in my opinion, all that good).

Maybe I was just disappointed because the Disney Taran, Eilonwy, and Gurgi were not MY Taran, Eilonwy, or Gurgi!




Lloyd Alexander wrote more than just Prydain books...

Born on this date in 1924, in Philadelphia, Pennsylvania, Lloyd Alexander loved to read the books his parents bought at the Salvation Army. Alexander's childhood was shadowed by the Great Depression, which hugely affected his stockbroker father (and most Americans) – but Alexander could get his escape by reading.

By age 15, Alexander wanted to be a writer. He worked the job that his parents found for him, as a bank messenger, while finishing high school by age 16, but he only went to college for one year before he decided to launch out on his career. He thought that he needed to have adventures before he began to write about others' adventures, so he enlisted in the U.S. Army during World War II. He was lucky not to be deployed until late in the war; he trained and served in intelligence and counterintelligence.

Spy stuff!

One of the places where he trained was Wales.

After the war, Alexander went to university in Paris, got married, and moved back to the U.S. to write.

He wrote books for seven long years before he got any of his books published!

His first hit was fantasy, meant for children: Time Cat. Because of that success, Alexander decided to stick with children's fantasy. He revisited his wartime home, Wales, for the settings of the Prydain books. The books are about  Welsh names and were inspired by aspects of Welsh mythology – although the beloved main characters and the plots of the Prydain books were entirely Alexander's own!


  • To celebrate Alexander's birthday, check out his books!

  • If you already know and love the Prydain books, did you know that there is a wiki about Prydain? (Don't check this out if you haven't read the books – loads of spoilers!)





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January 29 – Kansas Celebrates the Anniversary of its Statehood

Posted on January 29, 2016

By the numbers, out of the 50 states Kansas is:

  • the 34th state in the U.S.
  • the 34th largest state, by population
  • the 15th largest state, by area
  • the 43rd best economy
  • the 35th best quality of life (according to CNBC)
  • the 1st in average number of F3 to F5 tornadoes!

Named for the Kansa Native American tribe, Kansas was home of a lot of different Native American groups. It was such a battleground between slaveholders and abolitionists, it was called Bleeding Kansas during the Civil War.

Kansas is known for agriculture, The Wizard of Oz, Brown v. Board of Education, evolution hearings, the birth of Pastafarianism (aka the Church of the Flying Spaghetti Monster), cowboys, and of course tornadoes.

Also, Kansas is known for being flat. Supposedly, scientists determined that Kansas is flatter than an IHOP pancake.

Luckily, flat can be beautiful:






Now, about that science-saying-Kansas-is-flatter-than-a-pancake thing. Apparently, the “study” done by three scientists showed that the pancake was 130 millimeters wide, and the relief (the difference between the highest and lowest places on the pancake) was 2 millimeters. Now we have to compare the 130-to-2 ratio to Kansas: the state is 644 kilometers wide, and so it would need to have a mountain that is at least 9,908 meters tall in order to NOT be flatter than a pancake. But the very highest mountain in the entire world, Mount Everest, is only 8,848 meters tall. So – given the way the scientists did the study – everywhere on Earth is actually flatter than a pancake!

I think it's wise to point out that the scientists WERE doing their study with their tongues firmly in their cheeks!

Here are a couple of photos that show that Kansas is not, indeed, totally flat!





Did you know...?

  • According to multiple sources on the internet, it is illegal to hunt whales in Kansas.
  • It's probably really hard to break that law, since Kansas is as pretty much as far from an ocean as you can get, in the U.S.! Kansas is the very center of the “lower 48” states.
  • Apparently, it is ALSO illegal to hunt whales in Nebraska and Oklahoma (two more states with no contact with the ocean).
  • It turns out, there is no specific mention of whales in those states' laws. Instead, Kansas, like most states, has a law against hunting threatened species. Quoting from Oklahoma's code, “'Threatened' refers to any wildlife species or subspecies in the wild or in captivity that, although not presently threatened with extinction, are in such small numbers throughout their range that they may become an endangered species within the foreseeable future or that they may be endangered if their environment deteriorates.”
    It seems that someone realized that that could pertain to whales (there are, in fact, very few whales in that state), and that someone started the whole “it's illegal to hunt whales in Oklahoma” thing, which of course soon spread to other states.
  • You can't believe everything you read on the internet!

One more thing about Kansas...

I think that the Kansas City main library is one of the most interesting and beautiful libraries I've ever seen photos of...

...both inside...

...and out!




Also on this date:









Thomas Paine Day













Flight pioneer Lawrence Hargrave's birthday







Geologist Frederick Mohs's birthday






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January 28 – Happy Birthday, Dame Kathleen Lonsdale

Posted on January 28, 2016

Diamonds are a dame's best friends?

Dame Kathleen Lonsdale was an accomplished scientist, researcher, professor. She accomplished a lot of “firsts” for women in science. (“Dame” is an honorary title for women equivalent to “Sir” for men. Lonsdale was given the title Dame Commander of the Order of the British Empire in 1956 for her scientific work.)

One of her Lonsdale's students – a woman who went on to become a science professor herself – acknowledged that she learned a lot of science from Professor Lonsdale, but she ALSO said that she learned a lot about how to balance a career and a family from Lonsdale. And that is a really important thing!

Lonsdale was born on this date in 1903 in Ireland, but she moved to England when she was just five years old. At the time that she was attending high school, mathematics and science were not offered in the High School for Girls, so she ended up transferring to a High School for Boys for those subjects! She went on to earn Bachelor of Science and Master of Science degrees at university. Eventually she became the first woman to be a tenured professor at the University College London.

I'm sure you're dying to know what that diamond crack at the top of this article was all about? Well, Lonsdale's specialty was crystallography, the study of atomic and molecular structure. One of the things she worked on was the synthesis of diamonds. (That is, making diamonds, rather than digging up diamonds that were made naturally.)

Lonsdale also determined the structure of benzene rings, which are important organic compounds, and of hexachlorobenzene. She was a pioneer in the use of X-rays to study crystals. Remember, crystals are found everywhere in nature, from snowflakes to gemstones, from salts to organic compounds to minerals. Here are some cool pictures from modern crystallography:










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Anniversary of first ski tow in the U.S.




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