Celestial events Sep 2014: Third supermoon to start Sept. 9
September 4, 2014 - Supermoon
The third supermoon in 2014 will take place on Sept. 9. Earth’s healthy satellite will seem bigger and brighter than other unchanging full moons. Although not uncommon, a supermoon – scientifically called a perigee moon – can be utterly a spectacle, generally when it’s accompanied by what is called a “moon illusion.”
“Generally speaking, full moons start nearby perigee each 13 months and 18 days, so it’s not all that unusual,” Geoff Chester of a U.S. Naval Observatory told NASA Science News. “In fact, usually final year there were 3 perigee moons in a row, though usually one was widely reported.”
Since a moon follows an elliptical circuit around Earth, it is healthy that there are times when it passes closer to a planet. It’s nearer to Earth by about 50,000 kilometers when it’s on a perigee side of a circuit than when it’s on a round side. Supermoons start when a full moon scarcely coincides with a perigee.
The moon during a perigee is some-more or reduction 30 percent brighter and 14 percent bigger than when it’s on a round side of a orbit. Furthermore, when a moon is tighten to a horizon, it generally appears unnaturally vast – a materialisation called “moon illusion” that can't nonetheless be entirely explained. Thus, a supermoon appears like a outrageous universe as it rises adult a eastern horizon.
Although a occurrence of perigee moons is not unusual, there are singular incidents when it’s scarcely perfect. According to Chester in an progressing interview, near ideal supermoons like a one that occurred on Mar 19, 2011 (less than one hour from perigee) occur usually once each 18 years or so.