8 January 2018
TECHKNOWLEDGEY 2018 n BY JEFF ECKERT
Dark Matter Matters
There is an awful lot of detectable matter and energy
flying around the universe, but people who know how to
figure such things figure that it constitutes only about four
percent of everything that’s out there. The rest is either
dark matter ( 26 percent) or dark energy (70 percent) —
both mysterious and still theoretical. Neither one absorbs
or reflects light, making it tough to deal with.
However, astronomers postulate that dark matter
— and therefore dark energy — must exist, as nothing
else explains certain observable gravitational effects
on things like galaxies. Apparently, galaxies are
rotating so rapidly that without these dark forces to
counterbalance normal gravity, they would fly apart.
Nevertheless, through the efforts of a team
assembled by the Dark Energy Survey (www.
darkenergysurvey.org) including 400+ scientists and
25 institutions in seven countries, we now have a
fairly detailed map (see illustration) of dark energy
distribution over billions of years and 1,300 square
degrees of sky.
Collected data came from the Dark Energy
Camera, mounted on the Blanco 4 m telescope in
the Chilean Andes. Related computations ate up an
estimated 300,000 core hours — many of which were
executed on the Ruby Cluster computer at the Ohio
Supercomputer Center at Ohio State ( www.osc.edu).
OSC also built many components of the 570
megapixel camera, which was powerful enough to collect
light from galaxies up to eight billion light years away.
According to OSC documents, “The new dark matter
map is 10 times the size of the one DES released in 2015,
and will eventually be three times larger than it is now.”
COMPUTERS and NETWORKING
Got Your “i” on a Phone?
When Apple ( www.apple.com) released the iPhone X, there were two
common responses: “Wow, I gotta have one no matter what it costs,” and
“$1000? You must be crazier than a dog in a hubcap factory.”
If you lean toward the latter but don’t want to go Android, you might check
out a less trendy alternative: the iPhone SE. Sure, the X has some nifty features:
5.8 in vs. 4. 7 in display; almost double the screen resolution; a telephoto lens;
facial recognition ID; and “up to” 21 hours of talk time on a charge (vs. 14).
The similarities are numerous as well.
Both have a 12-Mp front-facing camera; up to 256 GB RAM; the A11
bionic 64-bit quad-core chipset and M11 motion processor; 4K video
recording; and splash, water, and dust resistance.
Instead of a Walmart price of $1,049 ($1,199 for the 256 gig version),
you’ll shell out only $349. Plus, SIM-free models are available so you can pick
your carrier later.
Of course, you still may be in a quandary about whether $349 is a real
deal, considering the wealth of Android phones
that cost $100 or less and do essentially the same
thing. Can’t help you there. ▲ Apple’s iPhone SE: A little smaller, a lot
Map of dark matter from gravitational lensing measurements
of 26 million galaxies.