Tuesday, January 27, 2009

Eye Candy

The Ecliptic

The plane of the Earth's orbit around the Sun is called the ecliptic. It is the path the Sun appears to follow against the background stars. Both the Sun and moon must be in this band for eclipses to occur. It also forms the part of the sky in which the planets are always seen.

In other words, as the Earth orbits, the inside of the orbit always faces the Sun, while the outside faces a band of stars which changes predictably each year.

Ancient astronomers were able to trace the ecliptic as a line across the sky, even though they didn't realize that the Earth revolved around the Sun. They simply mapped the position of the Sun relative to the other stars in the sky, noticing that every 365 days or so the constellations would recur, and the Sun would start going over the same locations again.

An equinox is a time of year when our planet is at a location where the ecliptic plane intersects the equator. On the day of the equinox, there are as many minutes of daylight as there are of night, hence the term "equinox," meaning "equal darkness".

We all know that the Earth spins like a top. Like a top, it wobbles a bit while it spins, so that its axis traces out a circle in the celestial sphere. This wobbling is called "precession". The effects of precession are barely noticeable to the human eye, so ancient astronomers must have kept records for thousands of years to have realized that it was occuring.

The ecliptic is divided into twelve sectors, named for the constellations they contain, commonly known as the signs of the Zodiac. Because of precession, the dates when the Sun is in each constellation no longer lines up with the dates associated with the astrological house of the same name.

Additionally, we have divived the year into equally long sectors even though the constellations aren't all the same size. The Sun passes through Scorpio in only seven days, while Virgo takes 44 days.

The appearance of each constellation of the Zodiac occurs predictably, but changes very slightly each year. It takes 2150 years for the equinox to shift from one constellation to the next, called an astronomical age. We are currently in the Age of Pisces (the Sun is in Pisces during the spring equinox), but in 2150 will enter the Age of Aquarius.
One complete wobble of the Earth takes 25,800 years, called a Great or Platonic Year.

More on precession in my next astronomy post. For my previos posts on astronomy, click here.

For an awesome coffee table book on outer space, filled with amazing pictures from all over the Universe, check out Astronomy: A Visual Guide, by Mark A. Garlick.

Sunday, January 25, 2009

Eye Candy

Spud: The Madness Continues

Spud: The Madness Continues, by John van de Ruit
$11.55 in the Hansisgreat Gift Shop
ISBN: 1595141901
This is the sequel to a book I reviewed about a year ago also worth checking out. You can enjoy this book on its own, but will know the characters and understand the plot better if you read the previous installment first.
John "Spud" Milton is fourteen years old and a student at a boarding school in South Africa as Apartheid is ending. Although the story occassionally touches on issues of race, it's mostly about a boy coming of age. To some extent it resembles Catcher in the Rye, but unlike Holden Caulfield, Spud is not an asshole.
In fact, he's a very sweet kid who spends most of his time getting into mischief with his gang, dubbed "the Crazy Eight", and obsessing about his first love whom he has clearly idealized. The fact that it takes place in Africa presents a new twist on the sometimes tired boarding school setting. The boys take a trip on a wild animal safari, something which would never happen in New England. They are also whipped when they misbehave, which rarely happens in American schools these days.
At the beginning of the book, he's still very child-like: his scrotum is hairless (from which his nickname is derived, for his testicles which resemble new potatoes) and he sings soprano in his school's boys' choir. By the end he's drinking, pining for sex, and dealing with all the other problems of true manhood.
He plays the part of the dove in a disastrous production of Noah's Ark, and visits London with his bohemian mother who accosts the help at their hotel when the bar doesn't open at 11 AM. His father comes up with one absurd, get rich quick scheme after another while his grandmother lapses into an obnoxious senility.
In spite of all this, Spud is never mortified as I would be. Insted, he deals with his family and friends' foibles with humor and dignity, clearly on the road to becoming a fine young man. When one of the Crazy Eight's pranks gets out of control, Spud is only concerned with doing right, not with escaping the consequences of his actions.
Don't expect too much action or controversy: this novel is based on the diary of a teenage boy, so it's mostly about longing for that first kiss and feeling self-conscious about his body. In its own quiet way, both Spud books are engaging and bring back positive memories about early adolescence. Although he was raised on a different continent, I related to the kid on almost every page. This is a good choice if you like coming-of-age novels, or if you're looking for a book for a teenager who is reluctant to read. Easy to get into, and enjoyable to the last chapter.

Saturday, January 24, 2009

Eye Candy


Lesothosaurus

Among the first true dinosaurs, lesothosaurus is considered an ancestor of the entire subsequent class of ornithischian (bird-hipped) dinosaurs, and was perhaps one of the first predatory dinosaurs from which all the great meat eaters developed. Although it was only the size of a modern house cat, this strange animal's teeth are almost like those of modern mammals: with pointed teeth at the front of the mouth which suggest that this creature may have eaten meat from time to time.

Lesotho is a remote, mountainous region in southern Africa, where fossilized remains of this dinosaur were first discovered in 1978. Lesothosaurus remains have also been found in South America, which was connected to Africa's west coast at the time. Because of its hot, dry conditions in an area relatively unmolested by man, Lesotho has been a valuable source for dinosaur hunters.

Lesothosaurus is very similar to the previously discovered fabrosaurus. In fact many scientists believe the two were actually the same animal. Remains of fabrosaurus, however, are so poor that it is impossible to say for sure.

Lesothosaurus had hollow bones and a small, light skeleton. Its only defense against a large predator would have been its ability to run away quickly, similar to the behavior of modern gazelles.

This animal shares many features with other ornithischian dinosaurs in addition to the bird-like hipbones. A "predentary" bone links the left and right sides of the lower jaw together. This bone was covered with a horny sheath, giving the animal a beak shaped mouth without the fleshy cheeks of most meat eaters. It also had a bone across its eye and eye socket, similar to those found in modern crocodiles.

It is interesting to note that, although it lived 208-200 milliuon years ago, ages before the first mammals, lesothosaurus had five digits on each hand and five toes on each foot.

For a long time, lesothosaurus was considered a very early ornithischian, related to hadrosaurs (duck-billed dinosaurs) and hypsilophodon. These animals were seperated from each other by more than 80 million years, however, leading one to believe that lesothosaurus actually has no close relative known to modern science. For this reason, it is difficult to classify on the dinosaur family tree.

Was lesothosaurus the mother of all carnivorous dinosaurs, or is the resemblance simply a coincidence?

For my previous posts on dinosaurs, click here.

Check out a couple good books on dinosaurs in the Hansisgreat Gift Shop. My two favorites are National Geographic Dinosaurs, by Paul Barrett; and Dinosaurus, by Steve Parker.

Thursday, January 15, 2009

Eye Candy


Returning Soon...

I apologize for not posting for such a long time. As you may know by now, I made the mistake of buying an expensive Apple iMac last year to run Hansisgreat. 47 days out of warranty, the whole computer crashed and the people at Apple have washed their hands of the whole affair.
My whole life was on that computer. Pity it was such an unreliable one. I'm gradually rebuilding all the research I did for future blog posts which was lost, and retyping it into my old Dell laptop (which cost 12% of what the iMac cost, but still works after 6 years).

Times are tough for all of us right now. It is especially galling, therefore, to be ripped off so unabashedly for such a major purchase. F**k Apple Computers. These things suck!

Sorry for the tirade. It's just been a nightmare over here and I needed to vent. More book reviews and light cultural interest stories soon, I promise.

Friday, January 9, 2009

Hansisgreat Down and Out

A quick update for those of you who are wondering where I've been...

A little over a year ago, I bought a new Apple iMac, which has been a nightmare from beginning to end. This is the most unreliable piece of equipment I've ever had the misfortune to own. After my last post, it stopped working completely. It's only 14 months old, 6 weeks out of warranty, and would cost $800 to repair.
Since I don't happen to have $800 lying around (I manage a bookstore and don't make that much) I am currently without a computer and therefore unable to publish on Hansisgreat.
My hope is to get a replacement PC soon. In the meantime, I'm afraid I must apologize for the delay. The people at Apple have been no help at all in getting this problem resolved.
I'll be back soon. In the meantime, if you're thinking of buying an Apple computer... just DON'T.

Best wishes,
Hans