With crackling leaves underfoot and shorter days on the horizon, it's time to stow away the summer gear, break out the sweatshirts and make our transition into cool evenings and frosty mornings. Below are just a handful of celestial highlights to look forward to in this season of pumpkins, apple cider and the occasional high-flying witch.
The rise of an unusual Harvest Moon (Oct. 5)
The 2013 Harvest Moon rising over Lick Observatory at the University of California. (Photo: fpettinati/flickr)
October's full moon has the unusual honor this year of being known as 2017's Harvest Moon. While that designation almost always goes to September's full moon, the naming scheme itself is actually based on math. Whichever full moon lies closest to the autumn equinox wins. Since fall arrived on Sept. 22, and September's full moon came on the 6th, October's full moon won the numbers game and became the Harvest Moon.
October is generally referred to as the Hunter's Moon, so-called by Native Americans for the time of year when people would hunt to build up stores for winter. With the start of frost season, it's also been referred to as the Freezing Moon and the Ice Moon.
The 2017 Harvest Moon will rise on Oct. 5, with peak fullness coming during the daylight hours at 2:40 p.m. EDT.
Catch the Draconids meteor shower (Oct. 7 and 8)
The first of two meteor showers this month, the Draconids get their name from the northern constellation of Draco the Dragon from which they appear to radiate. Like other showers, this one is caused by Earth passing through debris shed by a periodic, 1.2 mile-wide comet called 21P/Giacobini–Zinner.
While the light of a waning gibbous moon will wash out all but the brightest shooting stars, there's still reason to reserve a bit of time to look. Past Draonids sometimes have surprised astronomers with their extreme intensity. The showers of 1933 and 1946 in particular produced thousands of shooting stars per hour and rank as two of the best meteor storms of the 20th century.
Should history repeat itself, the evenings of Oct. 7 or 8 should give you your best shot at witnessing peak displays from this shower.
A close shave from an incoming asteroid (Oct. 12)
On Oct. 12, NASA will flex its Planetary Defense system, a consortium of more than a dozen observatories, universities and labs across the globe, when asteroid 2012 TC4 makes an extremely close flyby of Earth. The house-sized rock is expected to come anywhere from 170,000 miles to as few as 4,200 miles from the Earth's surface; a veritable close-shave in astronomical terms.
“This effort will exercise the entire system, to include the initial and follow-up observations, precise orbit determination, and international communications,” team leader Professor Vishnu Reddy of the University of Arizona's Lunar and Planetary Laboratory in Tucson said in a statement.
To spot this close visitor, you'll need at least a 10-inch telescope and an unimpeded view of the constellation Pisces. You'll also need to be fast. During its last approach in 2012, TC4 peeled through the constellation Sagittarius at a rate of one degree (two full moon diameters) every 5 minutes.
For updated coordinates ahead of its close approach, check out this site for more details.
Look for the zodiacal light (Oct. 15-30)
The triangular glow of the zodiacal light taken from the European Southern Observatory's La Silla Observatory in Chile in September 2009 only minutes after sunset. (Photo: European Southern Observatory/Flickr)
Spring and fall are the two best seasons of the year to catch the haunting zodiacal light, so if you missed them earlier this year, the latter half of October offers another opportunity. Visible only to those under relatively dark skies, this celestial phenomenon looks like light pollution but is actually sunlight glinting off solar dust. A 2010 study found that nearly 85 percent of the dust was caused by fragmentation from Jupiter-family comets.
To spot it, look for a pyramid-shaped glow rising above the eastern horizon just before dawn.
Pale blue Uranus draws near (Oct. 19)
The haunting pale blue of Uranus as captured by the approaching Voyager 2 spacecraft in 1986. (Photo: NASA/flickr)
Uranus, the seventh planet from the sun, will make its closest approach this year to on Oct. 22, placing it a mere 1.7 billion miles from our backyards. Despite this little pale dot being its best and brightest, it will be barely visible to the naked eye. Those wishing for a closer look should lean on a good pair of binoculars or a telescope.
Darkness under a New Moon (Oct. 19)
October's New Moon will give way to dark skies and excellent opportunities to view everything from Uranus to galaxies, star clusters and nebulae.
Look up for the Orionids meteor shower (Oct. 22)
The Orionids meteor shower will peak on the evening of Oct. 22. (Photo: Jeffrey Sullivan/flickr)
The Orionids meteor shower, created by debris left behind by Halley's Comet, is set to peak in the pre-dawn hours of Oct. 22. With the moon enjoying a rest, this leaves perfect conditions for viewing even the faintest shooting stars from this annual display. As many as 10 to 20 (and sometimes as many as 50 to 70) shooting stars will be visible each hour.
While the Orionids tend to originate from the constellation of Orion the Hunter, most displays can be viewed from any point in the evening sky. Grab a blanket, get comfortable and look up. Chances are, you'll quickly find yourself with a glut of wishes.
Take part in International Observe the Moon Night (Oct. 28)
Grab a telescope or binoculars and take part in International Observe the Moon Night on Oct. 28. (Photo: Kim Seng/flickr)
Without our moon, life on Earth would be much different. Our tides would be weaker, our nights much darker, and solar and lunar eclipses would cease to exist. The moon has also played a major role in slowing down the Earth's rotation over billions of years. If it wasn't there from the beginning to cause tidal friction, our days would last between 6 to 8 hours and a year would last between 1,100 to 1,400 days!
In honor of our closest neighbor in the sky, Oct. 28 celebrates International Observe the Moon Night. Since 2010, the organization behind the campaign has been sponsoring events around the world to encourage people to take time out of life on Earth to look up and gaze at the wonder that is our moon.
"In 2017, we are encouraging an eclipse-focus for the event, celebrating the total solar eclipse that crossed the United States in August, a lunar eclipse that will occur in January, and past and future eclipses visible around the world," the site declares. "Eclipses are both beautiful to behold, and scientifically interesting."