Image credit: s58y
The last quarter moon will come on June 30, 2013, at precisely 4:53 Universal Time (or at North America’s Central Daylight Time zone: June 29, 2013 at 11:53 p.m.). From around the world, tonight’s moon will rise over the eastern horizon around midnight local time (1 a.m. local daylight-saving time). The moon will reside at it highest point in the sky at roughly 6 a.m. (7 a.m. daylight-saving time) tomorrow, on June 30.
At last quarter moon, the moon appears half-illuminated in sunshine and half-engulfed in the moon’s own shadow. The terminator – the shadow line dividing the lunar day from the lunar night – will show you where it’s sunset on the waning moon.
For the Eastern Time Zone in North America, the last quarter moon falls at roughly the same time as tonight’s moonrise (around midnight or 1 a.m. daylight-saving time). For Africa, the last quarter moon happens at or near sunrise June 30. Click here to find out the precise times of moonrise and the last quarter moon for your time zone.
Day and night sides of Earth at instant of June 2013 last quarter moon
Day and night sides of Earth at the precise instant of the June 2013 last quarter moon (2013 June 30 at 4:53 Universal Time)
Here are some cool things to think about when you see a last quarter moon.
1. The last quarter moon mirrors a first quarter Earth. In other words, as we stand on Earth, gazing skyward, we’ll see the moon appear pretty much half illuminated in our sky. Likewise, if you could stand on the moon, you would see the Earth as half illuminated. One difference would be that the moon we see from Earth is waning. It’s a last quarter moon, heading toward new moon. The Earth you would see from the moon tomorrow is waxing. It’s a first quarter Earth, heading toward full Earth as seen in the lunar sky.
The first quarter Earth as seen from the last quarter moon on 2013 June 30 at 4:53 Universal Time
2. The last quarter moon shows you the direction Earth revolves around the sun. In other words, as you stand gazing at that last quarter moon, you are looking in a forward direction along Earth’s orbit. Earth moves through space at some 67,000 miles per hour! That’s 18 miles per second (30 km per second). We can’t anchor the last quarter moon in space, but if we could Earth would fly to the moon’s location in space in only a few hours.
Moon phases via Holt Physical Science class. Notice the location of the last quarter moon with respect to the incoming rays of the sun. Earth is moving around the sun in the direction of the last quarter moon - in other words, in this image, we're moving toward the bottom of the image.
By the way, tonight’s moon shines quite close to Uranus, the seventh planet outward from the sun. However, you’ll probably need binoculars and possibly a good sky chart to see Uranus in tonight’s moonlit glare.
Bottom line: Looking for the moon tonight? You won’t find it until around midnight or after. The moon reaches the last quarter phase on June 30, 2013 at 4:53 UT (June 29 at 11:53 p.m. CDT). A last quarter moon rises around midnight and sets around noon. No matter where you are on Earth, you’ll see tomorrow’s moon at its highest around 6 a.m. (7 a.m. dayligth-saving time) on June 30.
