The earliest definitions of time and time-interval quantities were based on observed astronomical phenomena, such as apparent solar or lunar time, and as such, time as measured by clocks, and frequency, as measured by devices ...
General Physics
Mar 22, 2016
0
131
The Internet Time Service operated by the National Institute of Standards and Technology (NIST) serves much of the Earth, with customers from around the globe. In one month of study alone, just two of the 20 NIST servers ...
General Physics
Mar 8, 2016
0
9
The number 2016 divided by 4 equals 504, exactly – with no remainder, which makes the year 2016, like the upcoming years 2020, 2024 and 2028 (and beyond), a leap year. We will get an "extra" day, February 29.
Space Exploration
Feb 26, 2016
0
43
You are about to enter the strange world of coordination geometries, where energy and atomic bonding interplay to give materials unusual properties, such as negative thermal expansion (you heat something and it gets smaller) ...
Materials Science
Jan 12, 2016
1
2010
It is no split-second decision. In fact, countries are at such odds over whether to do away with the "leap second"—an extra second periodically added to compensate for irregularities in the earth's rotation around the ...
Space Exploration
Nov 19, 2015
3
90
Many people didn't notice, but the last day in June was just a little bit longer than in years past.
Earth Sciences
Jul 1, 2015
9
65
Question: When is a minute not a minute?
General Physics
Jun 16, 2015
1
1547
(Phys.org)—DNA bricks are an odd phenomenon. They are nanostructures built from synthetic, single-strand DNA that self-assemble into 3D structures. Several years ago, researchers at Wyss Institute at Harvard demonstrated ...
A honeycomb is a very stable structure. If it has a larger hole, however, stability is largely lost. What might a honeycomb look like, which survives external forces in spite of a hole? Such stable types of known constructions ...
General Physics
Apr 23, 2015
0
2749
In another advance at the far frontiers of timekeeping by National Institute of Standards and Technology researchers, the latest modification of a record-setting strontium atomic clock has achieved precision and stability ...
General Physics
Apr 21, 2015
3
87
