Based on the latest national forecast, skies will be mainly clear on Tuesday evening across much of the contiguous (48) United States, as costumed kids arrive at the door looking for candy or some other Halloween treat.
A very large and expansive dome of high pressure will be positioned over the central United States and will bring mainly clear skies almost from coast to coast. The only regions that may have to contend with significant cloud cover would be near and around the Great Lakes thanks to instability generated by an upper-level disturbance and perhaps south Florida where a cold front might touch off some showers.
The rest of the country, however, will be in fine shape with mid-autumn stars and constellations plus two bright planets shining prominently in the early evening sky.
Related: The 25 scariest spaceflight moments show dangers in orbit and beyond
The lord of the rings and the king of the planets
If you plan to accompany children around your neighborhood, you might want to enlighten them by pointing out some of the objects that will be visible in the sky.
The first two objects that will attract attention will be the planets Saturn and Jupiter; about two hours after sunset Saturn will be visible about one-third up — 30 degrees high — in the south-southeast sky. Remember that your clenched fist held at arm's length is approximately equal to 10 degrees in width, so Saturn appears roughly "three fists" up from the horizon; it shines like a bright star with a sedate yellow tint.
Many consider Saturn as the most beautiful of all the planets. Its rings are still readily evident, with the north face tilted some 10 degrees to our line of sight. A telescope magnifying 30-power will bring them out; through a 4-inch telescope at 100-power, they are readily seen, while the view through larger instruments is jaw-dropping. Be prepared to hear exclamations from your young audience like "Awesome!" and "No Way!"
And you really can't miss Jupiter — the largest planet in our solar system. Although only about one-third as high — 10 degrees — compared to Saturn, it will be in the eastern sky, appearing to shine with a very bright, silvery-white light. With even a small telescope using low magnification, you'll be able to see its disk as well as all four of the famous Galilean satellites, so named because Galileo Galilei was the first to see them with his own crude telescope in 1610. On this Halloween night, you'll see two satellites to the east (left) of Jupiter, going outward, Io and Ganymede, and two others to the west (right), Europa and finally Callisto.
Halloween's moon
If you're outside as late as 8:30 p.m., the main celestial object that will attract everyone's attention will emerge from beyond the east-northeast horizon. Earth's nearest neighbor in space: the moon.
On Halloween evening, our natural satellite will be three days past its full moon phase.
One might get the impression that showing off the moon through a simple pair of binoculars might be a bit of a comedown from using a telescope. And yet, even a casual glance at a gibbous moon through 7-power binoculars can show you more detail of the lunar landscape than was seen by Galileo who gazed upon its surface more than four centuries ago. The moon is by far, the most satisfying object that a youngster can observe. It appears the biggest and exhibits lots of surface features. And best of all, it shows well even in heavily light-polluted cities.
Dark zones on the lunar surface were referred to as "mare" (pronounced "Mar-rey") or seas by the first observers to explore the lunar landscape with telescopes, though we know today that there is not a single drop of water in these regions.
The line separating light and dark on the lunar surface is called the terminator. Point out how mountains, valleys and craters all stand out in sharp relief right along the terminator, demonstrating just how rough and rugged the lunar terrain really is.
Watch out for fireballs!
Because they are active over Halloween, and they displayed an impressive outburst in 2005 at the end of October, the Taurid meteor shower is sometimes called the "Halloween Fireballs."
The bits of debris that make up the Taurids are a little larger than average, so they can result in brighter meteors and even fireballs, or exploding meteors (called bolides), that streak across the sky and leave incandescent trains in their wake. While they are most active during the second week of November, a few forerunners can show up on Halloween night, darting from out of the east-northeast part of the sky. So, if you or your young visitors see something resembling a flare from a Roman candle sweeping majestically across the evening sky, it may very well be a Taurid meteor.
Related: How to photograph meteors and meteor showers
Helpful hints for young telescope viewers
In the September 2019 issue of The Astronomical League Magazine "Reflector," author Richard W. Schmude Jr., offered some tips for those who plan to do public outreach for astronomy on Halloween:
"Firstly, children sometimes grab or touch the eyepiece, so use an inexpensive one. I gently warn children not to touch the telescope. In my area, parents have learned to tell their children not to touch the telescope. In some cases, a child will grab the eyepiece, causing the telescope to shift. For this reason, a Dobsonian telescope with a good finderscope is a good choice for Halloween outreach. A small stool or booster ladder may help very small viewers. Sometimes, parents hold their children up to look through the eyepiece. One may also place a monitor-connected video camera in the telescope and people can easily see the object on a screen." "Finally," adds Mr. Schmude, "I have my bag of goodies next to my telescope so that the children get two treats!"
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmers' Almanac and other publications. Follow us on Twitter @Spacedotcom and on Facebook.
Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.
