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Moonlight for 2018 Quadrantid meteors

The 2018 Quadrantid meteor shower is expected to exhibit its narrow peak January 3 around 21-22 hours UTC. The full supermoon nearly coincides, and moonlight will interfere with the shower.

View larger. | In 2014, as the Quadrantids were flying, those at far northern latitudes were seeing auroras. Photo by Tommy Eliassen.

The Quadrantid meteor shower is 2018’s first major meteor shower. The unfortunate news is that, in 2018, the closest and largest full moon of the year nearly coincides with the peak of this annual meteor shower. Although the Quadrantids have been known to produce some 50-100 meteors in a dark sky, their peak is extremely narrow. Peaks of the Perseid or Geminid meteor showers persist for a day or more, allowing all time zones around the world to enjoy a good display of Perseids and Geminids. But the Quadrantids’ peak lasts only a few hours. So you have to be on the right part of Earth – preferably with the radiant high in your sky – in order to experience the peak of the Quadrantids. What’s more, the shower favors the Northern Hemisphere because its radiant point is so far north on the sky’s dome. Follow the links below to learn more about the Quadrantids in 2018.

Peak dates for the Quadrantid shower in 2018

Where is the Quadrantids’ radiant point?

The Quadrantids are named for a constellation that no longer exists.

Quadrantid meteors have a mysterious parent object.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014.  Thank you, Barry.

Barry Simmons in Lake Martin, Alabama captured this Quadrantid meteor on the morning of January 3, 2014. Thank you, Barry.

Peak dates for the Quadrantid shower in 2018 In 2018, the Observer’s Handbook 2018 published by the Royal Astronomical Society in Canada gives the peak as January 3 at 21 hours UTC. The International Meteor Organization seems to be in close agreement, listing 22 hours UTC as the peak. Keep in mind the prediction of the Quadrantid peak represents an educated guess, not an ironclad guarantee. So you see … this shower is a gamble!

If that prediction of the peak holds true, the northeastern part of North America could have a good shot at viewing the shower on the morning of January 3 – if not for the almost-full waning gibbous moon. If you’re game, try your luck in the predawn hours on Janaury 3 and 4.

From mid-northern latitudes, the radiant point for the Quadrantid shower doesn’t climb over the horizon until after midnight.

Where is the Quadrantids’ radiant point? All other things being equal, for any meteor shower, you are likely to see the most meteors when the radiant is high in the sky. In the case of the Quadrantid shower, the radiant point is seen highest in the sky in the dark hour before dawn.

The radiant point of the Quadrantid shower makes an approximate right angle with the Big Dipper and the bright star Arcturus. If you trace the paths of the Quadrantid meteors backward, they appear to radiate from this point on the starry sky.

Now for our usual caveat. You don’t need to find the meteor shower radiant to see the Quadrantid meteors.

You just have to be at mid-northern or far-northern latitudes, up in the wee hours of the morning and hope the peak comes at just the right time to your part of the world. The meteors will radiate from the northern sky, but appear in all parts of the sky.

The now-defunct constellation Quadrans Muralis, for which the Quadrantids are named. Image via Atlas Coelestis.

The Quadrantids are named for a constellation that no longer exists. Most meteor showers are named for the constellations from which they appear to radiate. So it is with the Quadrantids. But the Quadrantids’ constellation no longer exists, except in memory. The name Quadrantids comes from the constellation Quadrans Muralis (Mural Quadrant), created by the French astronomer Jerome Lalande in 1795. This now-obsolete constellation was located between the constellations of Bootes the Herdsman and Draco the Dragon. Where did it go?

To understand the history of the Quadrantids’ name, we have to go back to the earliest observations of this shower. In early January 1825, Antonio Brucalassi in Italy reported that:

… the atmosphere was traversed by a multitude of the luminous bodies known by the name of falling stars.

They appeared to radiate from Quadrans Muralis. In 1839, Adolphe Quetelet of Brussels Observatory in Belgium and Edward C. Herrick in Connecticut independently made the suggestion that the Quadrantids are an annual shower.

But, in 1922, the International Astronomical Union devised a list 88 modern constellations. The list was agreed upon by the International Astronomical Union at its inaugural General Assembly held in Rome in May 1922. It did not include a constellation Quadrans Muralis.

Today, this meteor shower retains the name Quadrantids, for the original and now obsolete constellation Quadrans Muralis.

The radiant point for the Quadrantids is now considered to be at the northern tip of Bootes, near the Big Dipper asterism in our sky, not far from Bootes’ brightest star Arcturus. It is very far north on the sky’s dome, which is why Southern Hemisphere observers probably won’t see many (if any) Quadrantid meteors. Most of the meteors simply won’t make it above the horizon for Southern Hemisphere skywatchers. But some might!

In 2003, Peter Jenniskens proposed that this object, 2003 EH1, is the parent body of the Quadrantid meteor shower.

Quadrantid meteors have a mysterious parent object. In 2003, astronomer Peter Jenniskens tentatively identified the parent body of the Quadrantids as the asteroid 2003 EH1. If indeed this body is the Quadrantids parent, then the Quadrantids, like the Geminid meteors, come from a rocky body – not an icy comet. Strange.

In turn, though, 2003 EH1 might be the same object as the comet C/1490 Y1, which was observed by Chinese, Japanese and Korean astronomers 500 years ago.

So the exact story behind the Quadrantids’ parent object remains somewhat mysterious.

Bottom line: The first major meteor shower of 2018, and every year, the Quadrantid meteor shower, will probably be at its best in the hours between midnight and dawn January 3. Unfortunately, in 2018, the largest full moon of the year will almost coincide with the peak of this annual shower.

Celebrate 2018 with an EarthSky moon calendar!

Bruce McClure