Happy winter solstice! The event occurs today 21 Dec 2014 at 18:03 EST.

Sun 2014-12-21 18:03:00 -0500
Sun 2014-12-21 23:03:00 +0000

Why do mornings still get darker after the winter solstice? from BBC News

John Siracusa’s review of each OS X version are legendary, but the 10.10 article has a nice dive down into some of the details of the new Swift language and how it’s compiled. There are some impressive features here.

OS X 10.10 Yosemite: The Ars Technica Review, Swift
Introducing Swift at Apple Developer

In November, during the 30-day blog challenge, I wrote a series of posts on buying a telescope. With slight editing, I’ve combined them into a single document which also has a link in the menu up top.

Buying a Telescope

Scott Rosenberg writes “Code of Ages, Go and Swift take another step up the programming-language ladder.”

From Medium

Setting up two-factor authentication is a good idea, but it’s important to carefully save your recovery key in a safe place where you won’t lose it.

This story by Owen Williams makes this point clear.

From The Next Web, The dark side of Apple’s two-factor authentication

In a time of Richard Branson and Virgin Galactic, along with impressive amateur rocketeers and commercial space ventures, we might have forgotten about Bob Truax, one of the first commercial, private rocket jockeys.

From Wikipedia,

Truax also designed the Skycycle X-2, which he unsuccessfully tested on April 15, 1972 and June 24, 1973, and which Evel Knievel unsuccessfully used at the Snake River Canyon in 1974.

And also,

The X-3 Volksrocket (other names: Arriba One, Skycycle X-3) was a reusable space tourism rocket planned by Robert Truax after Evel Knievel provided a $1,000 research grant for a pilot study. Truax was looking for volunteers with enough money to help fund the effort and who wished to fly aboard his rocket. He got thousands of volunteers, but few of them had the financial resources.

The rocket used surplus components and was tested through 1991.

There was actually a TV show based on Truax called Salvage 1 and starring Andy Griffith in 1979.

Wikipedia article on Robert Truax.
Salvage 1 Series Pilot on Youtube

Do worm holes even exist? At Smithsonian.com, Victoria Jaggard writes the article “Would Astronauts Survive an Interstellar Trip Through a Wormhole?”

Given the state of current physics the answer is, No. The idea of worm holes has come and gone in the science world, though it never quite leaves. The Kerr metric solution to Einstein’s general relativity equations applies to “rotating” black holes and adds new twists, however there’s still not really a way for humans to get through.

Just like crossing an event horizon is beyond the edge of our universe, these ideas are beyond the edge of our science. Of course we don’t know everything and I have no doubt there are amazing things still to be discovered. I’d never say it can’t happen, just that we don’t have a good mechanism in our current astrophysics toolbox unless we toss in a little magic. Just like it is with faster-than-light travel.

Despite his ties to the film, [cosmologist Kip] Thorne is also pessimistic that a traversable wormhole is even possible, much less survivable. “If they can exist, I doubt very much that they can form naturally in the astrophysical universe,” he writes in the book. But Thorne appreciates that Christopher and Jonah Nolan, who wrote Interstellar, were so keen to tell a story that is grounded in science.

There’s more to come on this topic and other folks have weighed in.

Would Astronauts Survive an Interstellar Trip Through a Wormhole?

A team of astronomers using the Subaru Telescope’s Suprime-Cam to perform the Subaru Ultra-Deep Survey for Lyman-alpha Emitters have looked back more than [z=7] to find 7 early galaxies that appeared quite suddenly within 700 million years of the Big Bang. The team, led by graduate student Akira Konno and Dr. Masami Ouchi (Associate Professor at the University of Tokyo’s ICRR) was looking for a specific kind of galaxy called a Lyman-alpha emitter (LAE), to understand the role such galaxies may have played in an event called “cosmic reionization”.

The team looked at distant galaxies that primarily emit Lyman-alpha radiation, “Lyman-alpha emitters” or LAE, and saw fewer than expected, further back in time. There’s an apparent sudden cutoff at that redshift. The redshift corresponds to a distance and time in history that’s model dependent. The standard big bang model would put this at about 13.1 billion years and only 700 million years after the big bang itself. The cosmological-history implication is that these galaxies “suddenly” appear.

One thing is pretty certain. A cosmological redshift of seven indicates the universe was about 1/8 it’s current size at the time the light they observed was emitted. That’s 1 / (z + 1).

According to the team’s analysis, one reason that LAEs appeared very quickly is cosmic reionization. LAEs in the epoch of cosmic reionization became darker than the actual luminosity due to the presence of the neutral hydrogen fog. In the team’s analysis of their observations, they suggest the possibility that the neutral fog filling the universe was cleared about 13.0 billion years ago and LAEs suddenly appeared in sight for the first time.”

“However, there are other possibilities to explain why LAEs appeared suddenly,” said Dr. Ouchi, who is the principal investigator of this program. “One is that clumps of neutral hydrogen around LAEs disappeared. Another is that LAEs became intrinsically bright. The reason of the intrinsic brightening is that the Lyman-alpha emission is not efficiently produced by the ionized clouds in a LAE due to the significant escape of ionizing photons from the galaxy. In either case, our discovery is an important key to understanding cosmic reionization and the properties of the LAEs in early universe.”

Subaru Telescope detects sudden appearance of galaxies in the early universe at phys.org
Press release from ICRR
PDF of paper “Accelerated Evolution Of The Lyα Luminosity Function At z >~ 7 Revealed By The Subaru Ultra-Deep Survey For Lyα Emitters AT z = 7.3”

While looking for earlier posts about kids and programming, I came across this from a 2005-02-08 post. Someone sent this to me and I don’t know if it’s real or not. In any event, I enjoyed these.

These came from the annual “Dark and Stormy Night” competition. Actual analogies and metaphors found in high school essays:

1. Her face was a perfect oval, like a circle that had its two sides gently compressed by a Thigh Master.

There’s a question that have been worrying many of us for quite a few years now. How will today’s kids learn to program?

In the late 70s and 80s many kids were blessed with a microcomputer in their home that ran BASIC. Most folks don’t even know or remember that the first IBM PC booted straight up into BASIC, just like a Commodore 64. That’s where they learned to program. Those BASIC computers launched a whole generation of computer programmers.