Look Up! The Southern Delta Aquariids Meteor Shower Is Here

NASA/Bill Dunford
NASA/Bill Dunford

Wake a few hours before sunrise tomorrow and you can start your day with some shooting stars. The Southern Delta Aquariid meteor shower is peaking this week, and while it's not the brightest show of the year, conditions are good and the moonlight is minimal. Provided you live in an area lacking light pollution, you might be in for quite a treat.

Consider this shower to be the big warmup for the Perseids next month. You might even see a Perseid or two tonight (though it's not like they're labeled; just stick with probability when you tell everyone what you saw). So where did these meteors come from, and what's going on up there?

BUZZING THE SUN

Comet Machholz as recorded on March 1, 2005 NASA/JPL-Caltech/U. Washington/J. Morgenthaler

The Delta Aquariids are suspected to be the debris of 96P/Machholz, a sungrazing comet that orbits the Sun every 5.3 years. Sungrazers are the fighter pilots of the comet world, buzzing perilously close to the face of the Sun as they go about an orbit. Machholz is their Chuck Yeager. The comet's perihelion—that is, its point closest to the Sun in its orbit—is 0.1 astronomical unit. This puts it far closer to the Sun than Mercury, whose perihelion is 0.3 AU. (Earth is 1 AU.) When Machholz is at aphelion—its maximum distance away from the Sun—it reaches 5.9 AU, which is beyond even Jupiter's orbit.

It gets weirder yet. The comet's orbital inclination is 58 degrees. Rather than circle the Sun along the orbital plane of most planets (think of the light bulb and marble-on-wires model of the solar system from grade school), it is swooping up and away pretty dramatically. This adds up to a comet without fear, and as it goes about its orbit, it leaves behind a debris field of dust and sand-sized particles. That's where the Earth comes in. Every year as we travel our orbit, we cross through Machholz's trail, slamming into those particles at tens of thousands of miles per hour. When they burn up in our atmosphere, we get the stunning light show we call a meteor shower.

SEEING IT

As the shower's name implies, its radius—the seeming point of origin in our night sky—is the constellation Aquarius. Don't limit yourself to looking specifically in that area, though; all the sky is a meteor's canvas. You should give your eyes 30 minutes to adjust to the darkness. Bring a blanket and scan about 45 degrees up from the horizon. That's where the most action will begin to be apparent. Good news if you live in the southern hemisphere (or if you live near the equator in the northern hemisphere): You will get the best viewing of anyone on Earth.

The meteors should be visible until sunrise. If you oversleep or the weather is bad, try again tomorrow night. This shower doesn't have a pronounced peak like others, and you have a fair chance of catching something if you stick with it in the days ahead. The next big meteor shower will be the Perseids, which will peak on the night of August 12.

Celebrate the Holidays With the 2020 Harry Potter Funko Pop Advent Calendar

Funko
Funko

Though the main book series and movie franchise are long over, the Wizarding World of Harry Potter remains in the spotlight as one of the most popular properties in pop-culture. The folks at Funko definitely know this, and every year the company releases a new Advent calendar based on the popular series so fans can count down to the holidays with their favorite characters.

Right now, you can pre-order the 2020 edition of Funko's popular Harry Potter Advent calendar, and if you do it through Amazon, you'll even get it on sale for 33 percent off, bringing the price down from $60 to just $40.

Funko Pop!/Amazon

Over the course of the holiday season, the Advent calendar allows you to count down the days until Christmas, starting on December 1, by opening one of the tiny, numbered doors on the appropriate day. Each door is filled with a surprise Pocket Pop! figurine—but outside of the trio of Harry, Hermione, and Ron, the company isn't revealing who you'll be getting just yet.

Calendars will start shipping on October 15, but if you want a head start, go to Amazon to pre-order yours at a discount.

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A Rare Blue Moon Will Light Up the Night Sky This Halloween

Halloween will be even spookier this year.
Halloween will be even spookier this year.
VladGans/iStock via Getty Images

Wolves, werewolves, and people dressed as werewolves will have a bona fide full moon to howl at this Halloween. And it’s not just any full moon—it’s a blue moon.

What Is a Blue Moon?

Since a complete lunar cycle is 29.5 days long, this usually works out to one full moon per calendar month. If a full moon occurs on the first or second day of the month, however, there could technically be another one within the same month. When that happens—about once every 2.5 to 3 years, according to the Farmers’ Almanac—the second full moon is called a “blue moon.”

But up until the mid-20th century, blue moons had a different definition. The Maine Farmers’ Almanac and similar publications used to count full moons by season, so a year with 13 full moons meant that one season would have four (not three) full moons. To avoid messing with full moon nicknames that were tied to certain times of year (e.g. the “moon before Yule”), the third full moon in a season of four was named a “blue moon.”

In a 1943 column for Sky & Telescope, Laurence J. Lafleur mentioned that blue moons occur when a year has 13 full moons, but he didn’t go into detail about how the Maine Farmers’ Almanac determined which moon was, in fact, the blue one. Three years later, another Sky & Telescope author, James Hugh Pruett, wrote an article in which he incorrectly assumed that the blue moon was the second full moon in a month with two. The magazine repeated Pruett’s rule in future stories, and it eventually caught on with the general public.

Why Is It Called a “Blue Moon”?

Just like a pink moon isn’t pink and a worm moon isn’t crawling with worms, a blue moon isn’t actually blue. One theory holds that the name is derived from the Old English word belewe, or “to betray”—perhaps since blue moons betray the normal schedule of full moons. This lunar rarity is also said to be the origin of the phrase once in a blue moon.

The moon actually has appeared blue in the past. After a massive volcanic eruption, the ash in the sky can sometimes block red light particles, giving the moon a bluish tint. According to NASA, this happened after Indonesia’s Krakatoa erupted in 1883, and again when Mexico’s El Chichón spewed its molten guts a century later.

When Can I See October’s Blue Moon?

October's first full moon, the harvest moon, is coming on Thursday, October 1. The second one, the blue moon, will peak on Saturday, October 31, at 10:49 a.m. EST, so you’ll be able to see it before the sun rises or after it sets. Since a full moon on Halloween only happens once every 19 years or so, cross your fingers for clear skies that night.