22 January 2012


Well, a lot has been happening, so it's time to get caught up on science news. 

From the article Scientists Gear Up To Take A Picture Of A Black Hole ~  "The field of gravity around a black hole (see artist's rendition above, click to enlarge) is so immense that it swallows everything in its reach.  Not even light can escape its grip.  For that reason, black holes are just that ~ emitting no light whatsoever, their 'nothingness' blends into the black void of the universe.  So how does one take a picture of something that by definition is impossible to see?

"As dust and gas swirls around the black hole before it is drawn inside, a kind of cosmic traffic jam ensues.  Swirling around the black hole like water circling the drain in a bathtub, the matter compresses and the resulting friction turns it into plasma heated to a billion degrees or more, causing it to 'glow' ~ and radiate energy that we can detect here on Earth.

"By imaging the glow of mater swirling around the black hole before it goes over the edge of the point of no return and plunges into the abyss of space and time, scientists can only see the outline of the black hole, also called its shadow.  Because the laws of physics either don't apply or cannot describe what happens beyond that point of no return from which not even light can escape, that boundary is called the Event Horizon."

" .... Even though the black hole suspected to sit at the center of our galaxy is a supermassive one at four million times the mass of the Sun, it is tiny to the eyes of astronomers.  Smaller than Mercury's orbit around the Sun, yet almost 26,000 light years away, it appears about the same size as a grapefruit on the moon.  To see something that small and that far away, you need a very big telescope, and the biggest telescope you can make on Earth is to turn the whole planet into a telescope."

To learn how in the world (as it were) you do that, check out the link.

From Test Tube Yeast Evolve Multicellularity ~ "The transition from single-celled to multicellular organisms was one of the most significant developments in the history of life on Earth.  Without it, all living things would still be microscopic and simple.  There would be no such thing as a plant or a brain or a human .... [At the cellular level], since evolution acts on individual cells, it pays off for a cell to be selfish.  By hogging resources and hindering neighbors, a call can increase the odds that more of its own genes get passed into the next generation.  This logic is one of the reasons it has been challenging to imagine how multicellularity arose ~ it requires the subjugation of self-interest in favor of the group's survival."

The article goes on to describe a simple but elegant experiment to artificially select for multicellularity in yeast.  The results were startling ~ evolution into multicellular functioning, evidence of a rudimentary division of labor, and indications of the first steps toward cellular differentiation, all within a few dozen generations.  An embedded video demonstrates the process, one of the most fundamental in all of biology.

In a humorous aside, Sheril Kirshenbaum recounts the disconnect between science and journalism when she was asked by a television crew to Just Look Science-y.

And finally, with a special focus on the future of our presence in space, Marc Millis goes way out on a limb to predict An Optimistic History of the Next 40 Years.  As a self-described cynical romantic, I doubt that his projected accomplishments will come to pass quite that quickly, but I hope he's right and I'm wrong.  Cheers.

No comments:

Post a Comment