The Tau Herculids meteor shower could light up the night sky over North America

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Earth is expected to pass through the debris trail of a shattered comet Monday evening and early Tuesday morning. This could lead to a whole new meteor shower.

Night sky watchers in North America have the best chance of seeing the Herculid tau shower, with NASA recommending around 1 a.m. on the east coast or 10 p.m. on the west coast as the best times to look up. The moon is new, so there will be no moonlight to obscure the meteors.

However, there is no guarantee of a dazzling display even if the sky is clear and dark, NASA pointed out. It might do nothing.

The comet, officially known as 73P/Schwassmann-Wachmann, or SW3, was discovered in 1930 by German observers Arnold Schwassmann and Arno Arthur Wachman. It wasn’t spotted until the late 1970s, and in the 1990s the comet broke into several pieces, NASA said.

By the time SW3 passed Earth again in 2006, it was in nearly 70 pieces and has continued to fragment ever since, according to the release.

NASA said observations from the Spitzer Space Telescope published in 2009 indicated that some fragments were moving fast enough to be visible and exciting to space scientists.

Each year, there are about 30 meteor showers, which occur when Earth passes through the trail of debris left by a comet or asteroid, visible to the naked eye.

Some meteor showers have been around for centuries. For example, the Perseid meteor shower, which occurs every August, was first observed about 2,000 years ago and recorded by Chinese astronomers, NASA said. New meteor showers like this, should they materialize, are relatively rare.

Debris from SW3 will hit Earth’s atmosphere more slowly than other meteor showers and it is the speed at which the debris hits rather than the size of the debris that causes the shower.

Even if they are visible, that means the meteors would be much fainter, for example, than the eta Aquariids meteors earlier this month.

“It will be an all or nothing event. If the debris from SW3 was traveling over 220 miles per hour when it separated from the comet, we could see a nice meteor shower. If the debris had slower ejection velocities then nothing will come to Earth and there will be no meteors from this comet,” said Bill Cooke, who heads the Office of Meteoroid Environment at the NASA at NASA’s Marshall Space Flight Center in Huntsville, Alabama, in a statement. .

Meteor showers are usually named after the constellation from which they appear to radiate into the night sky, although Robert Lunsford, secretary general of the International Meteor Organization, said the tau Herculids were misnamed. He said they would appear to radiate from a constellation known as Bootes, northwest of the bright orange star known as Arcturus (alpha Bootis).

“The radiant should be a large part of the sky and not a specific point. So any slow-moving meteor in this general area of ​​the sky can be expected to come from SW3,” Lunsford said in a blog post.

“You don’t need to look directly overhead because meteors can appear in any part of the sky. They are actually more likely to appear at lower altitudes in the sky because at these altitudes, one is looking through a much thicker slice of the atmosphere than when looking straight up.

If the Herculid tau shower turns out to be a dud, fear not, there are several other opportunities to witness meteor showers this year.

The Delta Aquariids are best visible from the southern tropics and will peak between July 28-29, when the moon is 74% full.

Interestingly, another meteor shower peaks the same night – the Alpha Capricornids. Although a much weaker downpour, it has been known to produce bright fireballs during its peak. It will be visible to everyone, regardless of which side of the equator they are on.

The most popular Perseid meteor shower of the year will peak between August 11 and 12 in the Northern Hemisphere, when the moon is only 13% full.

Here’s the meteor shower schedule for the rest of the year, according to EarthSky’s meteor shower outlook.