1 00:00:00,390 --> 00:00:04,390 If you look outside on September 27th, 2015, 2 00:00:04,410 --> 00:00:07,520 you can catch a glimpse of a very rare event in the night sky: 3 00:00:07,540 --> 00:00:10,580 a supermoon lunar eclipse. 4 00:00:10,600 --> 00:00:14,600 To understand what this is – first, take a full moon. 5 00:00:14,620 --> 00:00:17,630 6 00:00:17,650 --> 00:00:21,660 Now add the closest approach the moon makes to the Earth on its elliptical orbit – 7 00:00:21,680 --> 00:00:25,680 which results in it looking up to fourteen percent larger in diameter. 8 00:00:25,700 --> 00:00:26,980 That's a supermoon. 9 00:00:27,000 --> 00:00:28,980 Now combine this with a lunar eclipse, 10 00:00:29,000 --> 00:00:33,340 when the Moon passes directly behind the Earth into its shadow - giving it a red tint. 11 00:00:33,360 --> 00:00:34,980 12 00:00:35,000 --> 00:00:37,400 Now you have a supermoon lunar eclipse. 13 00:00:37,420 --> 00:00:40,440 This is a really special event, because it doesn't happen very often. 14 00:00:40,460 --> 00:00:42,490 Let's take a look back. 15 00:00:42,510 --> 00:00:47,560 Since 1900, a supermoon lunar eclipse has only happened 5 times. 16 00:00:47,580 --> 00:00:50,600 A lot changes here on Earth in between these moments. 17 00:00:50,620 --> 00:00:54,760 In fact, the last time you could see this event was 1982. 18 00:00:54,780 --> 00:01:00,760 And if you miss seeing it in 2015, your next opportunity won't come until 2033. 19 00:01:00,780 --> 00:01:07,110 So mark your calendar and head outside on September 27th. 20 00:01:07,130 --> 00:01:20,427