This is an archived article that was published on sltrib.com in 2015, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.
If Tuesday feels a bit longer, that's because it will be.
A leap second will be added to the world's clocks on Tuesday — at 5:59:59 p.m. Mountain time — making the day one second longer.
"Somehow I doubt most people will notice," wrote Patrick Wiggins, NASA/JPL Solar System Ambassador to Utah, "though the last time a leap second was added, in 2012, it did crash a few websites."
Leap seconds happen from time to time, to keep clocks in sync with the Earth's rotation. The first use of leap seconds took place in 1972, when scientists found that clocks were off by 10 seconds and added 10 leap seconds to make up for it.
Another astronomical event happening in the next week, Wiggins wrote, is that on Monday, July 6, Earth will be at aphelion — the furthest point from the sun during Earth's orbit.
The difference between aphelion and perihelion, the closest point to the sun, is negligible — which is why it still will feel beastly hot this week. It's the tilt of Earth's axis that is the main cause for the difference in temperatures, making the days longer in summer in the Northern Hemisphere.