SCIENTIFIC AMERICAN / JANUARY 2015 / by Caitlin Murray

the digital economy and economic stagnation : at the same time that the digital economy has generated enormous wealth for shareholders and entrepreneurs, it has resulted in few new jobs / secular stagnation / in 2010 only 0.5 percent of the U.S. workforce were employed in industries that did not exist a decade earlier


ASTEROID REDIRECT MISSION (ARM) : the U.S. wants to send humans to Mars by 2030, as the first step NASA plans to send astronauts to a small asteroid that would be brought into a stable orbit around the moon


Research has shown that animal's common name can affect whether people want to protect it.


Do we inhabit the best of all possible worlds ? : over the past two decades astronomers have found more than 1,800 exoplanets and statistics suggest that our galaxy harbors at least 100 billion more / "superhabitable world" / we know that the earth will become far less-friendly in the future / about 5 billion years from now, our sun will have largely exhausted its hydrogen fuel and begun fusing more energetic helium into its core, causing it to swell to become a "red giant" star that will scorch the earth to a cinder / Long before that, however, life on Earth should have already come to an end / as the sun burns through its hydrogen, the temperature at its core will gradually rise, causing our star's total luminosity to slowly increase, brightening by about 10 percent every billion years / such change means that the sun's habitable zone is not static but dynamic, so that over time, as it sweeps farther out from our brightening star, it will eventually leave earth behind / recent calculations suggest that Earth is not in the middle of the habitable zone but rather on the zone's inner cusp, already teetering close to the edge of overheating

we began our work with the understanding that a truly long-lived host star is the most fundamental ingredient for superhabitability; after all, a planetary biosphere is unlikely to survive its sun's demise / our sun is 4.6 billion years old, approximately halfway through its estimated 10-billion-year lifetime / if it were slightly smaller, however, it would be a much longer-lived K dwarf star / K dwarfs have less total nuclear fuel to burn than more massive stars, but they use their fuel more efficiently, increasing their longevity

If our own earth were located in the habitable zone of a small K dwarf, the planet's interior would have grown cold long before the star expired, inhibiting habitability / for example, a planet's internal heat drives volcanic eruptions and plate tectonics, processes that replenish and recycle atmospheric levels of the greenhouse gas carbon dioxide / Without those processes, a planet's atmospheric CO2 would steadily decrease as rainfall washed the gas out of the air and into rocks / ultimately the CO2-dependent global greenhouse effect would grind to a halt, increasing the likelihood that an Earth-like planet would enter an uninhabitable "snowball" sate in which all of its surface water freezes.


Two thousand years ago a storm drove a Roman ship against a sheer rock wall on the north side of the remote Greek island of Antikythera / the boat sank, along with coins, gold jewelry, dozens of large marble and bronze statues and an extraordinary, bronze clockwork device now counted as the first analog computer / the wreck lay at the bottom of the sea, 165 feet down, untouched until 1900, when one day sponge divers came upon it / the divers were equipped with little more than a helmet and a long hose to the surface for air; they struggled just to reach the decayed vessel / one of them died, and two others were paralyzed.

new expedition last October : computerized breathing system - the gear cut down on the rate at which nitrogen builds up in the tissues, allowing him to prod the shipwreck for an hour and a half before turning back / the ascent still had to be slow after such a long submersion; short brought along a magazine so he could read at the planned stops upward.

most of the best ancient statuary has come not from land but from the sea

time stops on shipwrecks

mapping : mapping the entire regions of deep sea-floor relatively quickly using a small fleet of autonomous underwater robot vehicles / one goal : to chart the entire Aegean Sea bottom from Crete to the Greek mainland