Welcome to August, a month defined by loud cicadas, pool parties, humidity and children fretting about an impending return to school. When it comes to celestial happenings, however, there is no larger star this month that our own moon. From a partial lunar eclipse to the first coast-to-coast solar eclipse in almost a century, the moon will be the cause of most eyeballs drifting towards the heavens over the next several weeks.
Below is a small sampling of some of the night and day celestial events to look forward to this month. Wishing you all clear skies!
The rise of the full Sturgeon Moon (Aug. 7)
The full Sturgeon Moon is so-named for the fish that are easily caught in August and early September. (Photo: Paul Kline/flickr)
August's full moon, nicknamed the Sturgeon Moon, will rise for the U.S. Eastern Seaboard on the evening of Aug. 7 at 8:05 p.m.
The Sturgeon Moon gets its name from the species of fish native to both Europe and the Americas that is easily caught this time of year. Other nicknames include the Corn Moon, Fruit Moon and Grain Moon. In countries experiencing winter, such as New Zealand, native Māori called this full moon "Here-turi-kōkā" or "the scorching effect of fire is seen on the knees of man." This reference is to warm fires that glow during the Southern Hemisphere's coldest month.
Partial lunar eclipse (Aug. 7 & 8)
Observers in Africa, Asia and Australia will see August's partial lunar eclipse in its entirety. (Photo: Forrest Tanaka/flickr)
As a kind of consolation prize for missing out on this month's total solar eclipse over North America, those living on the continents of Africa, Asia and Australia will bear witness to a partial lunar eclipse. Spectators in Europe will catch the tail end of the eclipse as the moon rises around 7:10 p.m. on Aug. 7.
This phenomenon occurs between two to four times a year when the moon passes through a portion of the Earth's shadow. Because the shadow cast is more than 5,700 miles wide, lunar eclipses last much longer than solar eclipses. In some instances, totality can occur for as long as 1 hour and 40 minutes. As a reference, maximum totality for the Aug. 21 solar eclipse will top out a mere 2 minutes and 42 seconds. The longest, at over 7 minutes, won't take place until the year 2186.
This month's partial lunar eclipse is the last of the year. Next year, total lunar eclipses will take place in January and July.
Perseid meteor shower (Aug. 12)
A composite shot of last year's Perseid meteor shower over Turkey. Notice how the path of the meteors appears to race from the constellation Perseus. (Photo: NASA)
Regarded as one of the best celestial light shows of the year, the Perseid meteor shower occurs from July 17 to Aug. 24 and peaks on the evening of Aug. 12.
The shower, sometimes creating as many as 60 to 200 shooting stars per hour, is produced as Earth passes through debris left over from the orbit of Comet Swift-Tuttle. This 16-mile-wide periodic comet, which completes an orbit around the sun every 133 years, has been described as "the single most dangerous object known to humanity." This is because every instance of its return to the inner solar system brings it ever closer to the Earth-moon system. Though astronomers believe the comet bears no threat for at least the next 2,000 years, future impacts cannot be ruled out.
If the comet were to hit Earth, scientists believe Swift-Tuttle would be at least 27 times more powerful than the asteroid or comet that wiped out the dinosaurs. For now, you can take in the beauty of the debris from this harbinger of doom by looking north towards the constellation Perseus. Because the moon will be three-quarters full, you'll need to search out a nice dark sky to escape any light pollution from urban environments.
Total solar eclipse (Aug. 21)
A total solar eclipse as captured over the Southern Hemisphere in November 2012. (Photo: NASA Goddard Space Flight Center)
By far the biggest celestial event in ages, Aug. 21 marks the first time since June 1918 that a total solar eclipse will race from coast to coast across the United States. Cities and towns along the 72-mile-wide path of totality are preparing for an influx of visitors, with millions of Americans expected to drive to view the rare phenomenon. Those outside totality will still experience a show, with partial solar eclipses happening over much of North America. Regardless, everyone will want to invest in a pair of special solar eclipse glasses to avoid ruining your eyesight.
Total solar eclipses occur when the new moon moves between the Earth and the sun and casts its shadow on the planet. This shadow is comprised of two concentric cones –– the larger penumbra, which from Earth only shows the sun partially blocked, and the much smaller umbra, which blocks the sun completely. It is within this latter cone that totality will occur, giving spectators on the ground what's considered by many to be a "once-in-a-lifetime" experience.
The Great American Eclipse will actually first start out in the Pacific (at this point, it will actually, unbelievably rise while completely eclipsed!), making landfall on the Oregon community of Lincoln Beach at 10:16:01 a.m. (PDT). From there, the moon's shadow will continue to race across the U.S. The point of greatest eclipse, where the axis of the moon's shadow passes nearest to the center of Earth, will take place in Hopkinsville, Kentucky and last 2 minutes and 40.1 seconds. In celebration of the event, the town has temporarily renamed itself "Eclipseville," and expects anywhere from 55,000 to 150,000 tourists to visit in advance of Aug. 21.
The next total solar eclipse over the U.S. will take place on April 8, 2024.
New moon (Aug. 21)
August's new moon will not only create a show during the day, but also leave the heavens to glow unimpeded by night. (Photo: Coconino National Forest/flickr)
Fresh after wowing the U.S. during the day with its solar theatrics, August's new moon will give way to dark skies for the next several nights. This is the perfect opportunity to grab a blanket and head outside into the still-warm summer evenings to enjoy the heavens in all their glory. With some remnants of the Perseids still visible, it will also offer a chance to catch some of the faintest shooting stars.
Look for Earth's shadow (All year)
The Earth's shadow and 'Belt of Venus' as captured above Mauna Kea, Hawaii. (Photo: Jay El Eskay/flickr)
Ever wonder what causes the beautiful bands of color in the eastern sky at sunset or the western sky at sunrise? The dark blue band stretching 180 degrees along the horizon is actually the Earth's shadow emanating some 870,000 miles into space. The golden-red portion, nicknamed the "Belt of Venus," is Earth's upper-atmosphere illuminated by the setting or rising sun.
Now that you know about this phenomenon, choose a night or morning sometime to try and pick it out. You'll need a western or eastern horizon that's fairly unobstructed to get a clear view of our planet's huge curved shadow.
Looking ahead to September
As fall beckons, the biggest event next month will be the dramatic death dive of the Cassini spacecraft into Saturn. Taking place on Sept. 15, Cassini will make discoveries about Saturn right up until its fiery conclusion, with unprecedented photos and data captured and transmitted during its final moments.