Astronomy

Can a meteor shower happen simultaneously all around the planet?

Can a meteor shower happen simultaneously all around the planet?

In the original book, the classic 1962 movie and the modern 2001 re-make for TV. The store "The day of the Triffits" depicts a meteor shower that happen all around the Earth at the same time, and leaves everyone who sees it blind the following days.

Given the nature of how the Earth rotates, moves around the Sun and a meteor field (required to create a shower of many meteorites). Is it really possible for such an event to happen everywhere at the same time?

This is kind of an important plot in the story, because if one side of the planet goes blind first they can warn the other.


Realistically, no, that cannot happen. Most meteor showers that we experience on Earth - the most famous being the Perseids and the Leonids - are a result of comets passing roughly through our orbit and leaving behind debris that was burned off as the comet passed by the Sun. We then come along, sweeping through this debris and from our perspective on Earth, we see a shower of meteors raining down on us.

That implies two important things. First, we primarily see meteors as we sweep through the debris from comets. They are not objects which have made a trajectory for Earth and hit us head on. Second, we only see meteors when we're on the side of the planet facing the orbital direction of the Earth.

That being said, for the sake of the story, one could envision an alien race of sufficiently advanced technology surrounding our planet with asteroid and comet debris and subsequently "dropping" these meteroids on us from everywhere all at once. I'm not sure if aliens are involved in the story you've linked, but aside from third party intervention, there's now way you're going to see meteors from every place on Earth all at the same time.


Scientists track meteor shower to unusual comet seen every 4,000 years

Meteor showers are the dazzling result of cometary debris building up along well-worn paths through the solar system, then burning up in Earth's atmosphere as our planet crosses that dust trail.

It's hard to call a path well-worn when something passes by only once every 3,967 years. But it turns out that type of long-period comet can still be tied to a specific meteor shower, as scientists have done with Comet C/2002 Y1 Juels-Holvorcem and the UY Lyncids shower. The research that connected the long haul ice ball and the shower triples the number of celestial displays that scientists have tied to specific comets that take more than 250 years to orbit the sun.

"Until recently, we only knew five long-period comets to be parent bodies to one of our meteor showers," Peter Jenniskens, a meteor astronomer at the SETI Institute and the lead author of the new research, said in a statement. "But now we identified nine more, and perhaps as many as 15."

For some perspective, Comet C/2002 Y1 Juels-Holvorcem most recently made a close approach of the sun in 2003 &mdash which means its last such visit was around 2,000 B.C., when Egypt's Great Pyramids were just a few hundred years old, and its next pass of the sun won't occur until nearly the year 6,000.

Typically, a shorter orbit means a comet retraces its path more regularly, scattering more rubble that can become more "shooting stars" when Earth plows through the debris. That means it's difficult for skywatchers to notice meteor showers caused by comets with orbits beyond about 250 years or so.

The best known long-period comet that triggers a meteor shower is comet C/1861 G1 Thatcher, which causes the April Lyrid meteor shower. Other long-period comets' showers are less dramatic, even those scientists had previously identified, like the Aurigids (debris from C/1911 N1 Kiess) and the Leonis Minorids (from C/1739 K1 Zanotti).

The scientists behind the new study wanted to find more such connections, so they turned to a program called Cameras for Allsky Meteor Surveillance (CAMS), which includes observation stations across the United States and around the globe, including in New Zealand, Namibia, Chile and the United Arab Emirates &mdash networks totalling more than 500 individual cameras all told, all watching for meteors.

"These are the shooting stars you see with the naked eye," Jenniskens said. "By tracing their approach direction, these maps show the sky and the universe around us in a very different light."

Looking at such huge amounts of meteor sightings, scientists can pick out subtle meteor showers based on tracking only a few shooting stars to similar origin points in the sky, called radiants. So astronomers combined that analysis of a decade of observations with NASA's database of comets and their orbits.

The scientists found at least nine new matches between meteor showers and long-period comets, and identified another six potential matches. The research tracks down the comets responsible for esoteric meteor showers, like December's sigma Virginids and July's Pegasids, caused by debris from C/1846 J1 Brorsen and C/1979 Y1 Bradfield respectively.

Most of the comets in the research swing past the sun every 400 to 800 years or so, a quite respectable calendar. Three comets joined Juels-Holvorcem is a bit of an outlier with orbits longer than 1,000 years. Scientists have tied a few other long-period comets to specific meteor showers, but can't quite pin down their orbital periods.

Among the meteor showers studied, the researchers noticed an intriguing trend: Displays from long-period comets tend to last several days, and the radiant appears to move like a smudge on the sky. The scientists on the new research think the effect may be caused by a comet's orbit shifting between loops, so that the rubble fields don't align as cleanly as they do for short-period comets.

"This was a surprise to me," Jenniskens said. "It probably means that these comets returned to the solar system many times in the past, while their orbits gradually changed over time."

The research is described in a paper that will be published this autumn by the journal Icarus.


Can a meteor shower happen simultaneously all around the planet? - Astronomy

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A Fireworks Show in the Sky
The very first thing we will discuss is the difference between a meteor and a meteorite. The real answer is that basically there really isn't any. Both are small objects that crash into Earth's atmosphere at a speed of several thousand miles per hour.
A meteorite is an object that is large enough that it doesn't burn up completely before it hits the ground. A meteor is smaller and does burn up up completely before it hits the ground. What makes up the annual meteor showers, like the Persieds and Leonids, though, is pretty special. What causes these two famous annual events is the Earth passing through the very long tails of two comets!

Regular Visitors from Outer Space
The annual Perseid and Leonid meteor showers are made possible because of two comets that make regular visits to our solar system. The Leonids are caused when Earth passes throught the tail of Comet Temple-Tuttle, which sweeps through our solar system once every 33.2 years. The Persieds are caused by Comet Swift-Tuttle, which visits our solar system every 130 years.
When these two comets visit our solar system, they leave behind trails that are thousands miles long made up of very small particles of dust and ice. As Earth makes its annual journey around the Sun, it passes through the tails of these two comets. As our planet goes through these two trails of dust, the particles burn up in our atmosphere, which results in the meteor showers that we see in the sky.

Watching a Meteor Shower
The Perseid meteor shower occurs during August every year and the Leonids occur during the last part of November. You can check the Sky Maps section here at Astronomy for Kids during those months to see when the best times are for seeing these two annual events. We will also tell you where in the sky to look for the meteors.
Meteor showers are usually best viewed during the very early hours of the morning. You will get the best results if you go out of the city to an area where the skies are truly dark. Give your eyes at least half an hour to get used to the darkness and then lay on the ground and just look up. Using a telescope or binoculars doesn't help much, as you need to watch the whole sky to make sure you don't miss anything.
After watching the dark sky for a while, which is ususally interesting in itself, you should start seeing bright streaks of light as the meteors race across the sky. How many you will see can vary from as few as three or four an hour to as many as several hundred an hour. In either case, it's quite a sight to see.

There is an Adobe ® Acrobat ® file (19k) for Meteor Showers. You can view the file online by clicking here. You can save the file on your computer by right-clicking on the link.
You will need the free Adobe ® Acrobat ® Reader TM to view the file.


What causes a meteor shower?

Where do meteors come from, and what causes a meteor shower? A guide to the science of shooting stars.

This competition is now closed

Published: July 27, 2020 at 8:48 am

A lthough seemingly empty, the space between the planets of our Solar System is teeming with vast numbers of meteoroids, small pieces of rock and dust largely originating from comets and asteroids but also, to a lesser extent, from the terrestrial planets and rocky satellites. A small number even originate from outside our Solar System: so-called interstellar dust.

Meteors are produced when particles of interstellar dust enter Earth’s atmosphere at extremely high speeds (ranging from around 11km to 72km per second) causing them to burn up and leave a bright momentary streak across the sky.

Earth encounters approximately 40,000 tonnes of extraterrestrial dust every year.

Although this may sound like a lot, on a typical night it means you might see just a few meteors an hour streaking randomly across the sky. These are called sporadic meteors.

At certain times of the year these numbers can increase to around 100 meteors an hour in events called meteor showers, as Earth ploughs through denser streams of particles on its orbit around the Sun.

Currently, the Eta Aquariid meteor shower is peaking, making it the one to watch out for.

For more info, read our meteor shower guide.

The oldest meteor shower

Of all meteor showers that occur today, one of the oldest known is the Lyrid meteor shower. Observational records for it date back to 687 BC.

In these ancient times, meteor showers were interpreted as portents and then later as phenomena of the upper atmosphere. Their extraterrestrial nature was not realised until the idea of an Earth-centred Universe lost favour and astronomers became intrigued with meteors.

This was spurred on by the occurrence of spectacular meteor showers in the 19th and 20th centuries, as well as the findings from studies of meteorites – fragments of larger meteors that survive atmospheric entry and reach Earth’s surface.

We now know that the debris streams which produce meteors are left behind by comets – and occasionally asteroids, such as the Geminid meteor shower – during their passage through the inner Solar System.

The ice that binds the rocky and dusty constituents of comets is heated by the Sun and turns to vapour, flowing outwards from the nucleus and carrying these grains with it.

These grains create a trail of particles that follows approximately the orbit of the parent comet.

The orbits of comets

While Earth’s orbit around the Sun is roughly circular, comets whose paths cross the inner Solar System have orbits that are typically highly elliptical and inclined to the ecliptic.

This means the paths of Earth and cometary debris can, albeit rarely, intersect. In such cases, a meteor shower will be observed annually when Earth reaches this point in its orbit.

As Earth hits these trails, meteors viewed from the surface appear to radiate from specific points in the sky.

These meteor showers are given names relating to the constellations that are nearest these radiant points. The Leonid meteor shower, for example, appears to originate from the constellation of Leo.

Read our beginner’s guide to meteor showers for details of when to see each of the annual meteor showers and what the theoretical peak number of meteors per hour will be.

These predictions of meteor shower timings and intensities are generated by using a combination of past observational data from radar and optical telescopes and computer modelling.

Observations provide details of the activity profile (how the number of meteors changes as Earth barrels through the stream), while computer models allow us to simulate and study the release and subsequent movement of particles from particular comets.

Let’s take a look at the science behind one of the most spectacular meteor shower displays in the calendar: the Perseids.

The science of the Perseids

The Perseid meteor shower, with its radiant point in the constellation of Perseus, makes a great starting point for those interested in viewing meteors.

Soaring through Earth’s atmosphere at about 60km per second, the showers start in mid-July and peak in intensity around 12 August.

The best time to observe will be after midnight. As with all meteor showers, we see more meteors after midnight when we are on the side of Earth facing forward along its motion around the Sun, meaning we run into more meteoroids.

It’s estimated that the total mass of material contained within the Perseid stream is somewhere upwards of 10 billion tonnes.

Comet 109P/Swift-Tuttle is the parent of the Perseids and has an orbital period of about 133 years.

Its last trip through the inner Solar System was in the early 1990s, generating increased shower intensity in 1991, 1992 and 1993.

In fact, during the 1993 Perseid meteor shower, a meteoroid is believed to have impacted the OLYMPUS satellite, starting a chain of events that ultimately led to its demise, while onboard the Mir space station, cosmonauts reported hearing pings believed to have been meteoroids impacting the station’s hull.

The future of meteor showers

Meteor showers are observed annually, and some have been recorded for millennia, but for how long will they continue?

The answer is entwined in the fate of the parent comet. Ultimately, the meteor shower will begin to diminish when the comet is no longer able to top up the debris stream.

The comet could disintegrate, it could be gravitationally perturbed by a planet into another orbit, or even simply become dormant after losing all of its volatile ices.

So, while well-known and well-loved meteor showers like the Perseids exist, take the time to step outside, look up and try to catch sight of a few.

Dr Penny Wozniakiewicz is a planetary scientist and space dust expert based at at the University of Kent.


How to see the Eta Aquariid meteor shower

What is the Eta Aquariid meteor shower, when does it happen and how can I see it in 2021?

What is the Eta Aquariid meteor shower?

The Eta Aquariids is a moderately active meteor shower associated with the Comet Halley.

When is the Eta Aquariid meteor shower in 2021?

The Eta Aquariid meteor shower will peak between midnight and dawn on 6 May 2021.

This shower favours the Southern Hemisphere and will appear low in the sky for Northerly latitudes (such as the UK) in the early predawn hours.

Nevertheless, it should still be possible to see the shower in the eastern sky, even when the radiant is below the horizon.

Meteors are pieces of debris which enter our planet’s atmosphere at speeds of up to 70 kilometres per second, vaporising and causing the streaks of light we call meteors.

Where does the name Eta Aquariid come from?

Like with most meteor showers, the name comes from the constellation in the night sky that it appears to radiate from. In this case, it’s the Aquarius constellation. But why isn’t it called the 'Aquarid' meteor shower? This is because, more specifically, the name comes from one of the stars from this constellation: Eta Aquarii.


Celebrating the End of 2020? Look Up! Meteor Shower Rains Nightly Fireworks

One of the most spectacular meteor showers of the year, the Geminids , will peak this year on Monday morning, Dec. 14, lavishing the skies with as many as 120 meteors every hour.

And this year, the absence of the moon means darker skies while you enjoy the "falling stars."

If the weather is nice, cold December mornings often bring crystal clear skies, and this year the waning crescent moon will be gone most of the night, only appearing in the last moments before dawn as a thin sliver.

A Perseid meteor, captured over Park City, Utah. (NASA/Bill Dunford)

It&rsquos simple math: abundant meteors, plus a clear dark night, minus the moonlight, equals the possibility of dazzling rewards!

How To Watch the Geminids

After midnight following Sunday evening, in the early morning hours of Monday, Dec. 14, find a good, safe place where you can set up a cot or roll out a blanket on the ground and look up.

The meteors will appear to radiate from near Gemini , the Geminids&rsquo namesake constellation. By 2 a.m., Gemini will be almost directly overhead, 85 degrees above the southern horizon. Look for the &ldquotwin&rdquo stars Castor and Pollux , a pair of equally bright stars set about five degrees apart, or the width of four fingers.

View of the sky at 2 a.m. on Dec. 14. The radiant of the Geminids meteors (shown as red lines) is in the constellation Gemini, and will be almost directly overhead, and slightly to the south. (Graphic made using Stellarium)

With your sights set high, lay back and relax as (You hope!) a multitude of meteors rain down around you. If conditions are good, you may see two or so each minute. Though their radiant point is in Gemini, the meteors can appear anywhere in the sky, so use your peripheral vision to catch as many as you can.

Cloudy Weather Option: With a Bay Area forecast of cloudiness on Sunday evening and possible rain Monday morning, if you still want to see Geminids, check out the NASA Meteor Watch page, where the shower will be live-streamed from a camera at NASA's Marshall Space Flight Center in Huntsville, Alabama from 5:00 p.m. Sunday evening to 1:00 a.m. Monday morning, PST.

Another factor that affects how many meteors you see is light pollution .

If you live in or near a city, the light from cars, buildings, billboards, and streetlamps will reflect from particles in the atmosphere above, forming a pale glow to compete with the light of meteors, particularly the fainter ones.

Though this won&rsquot prevent you from enjoying the brighter meteors, it will subtract from the number you can see, so finding a place with dark skies, far away or sheltered from urban lights, will add to the experience.

Here are some ideas for good viewing places around the Bay Area.

Where Do the Geminids Come From?

Meteor showers happen when Earth passes through a trail of dust, usually left behind by a comet as it orbits close to the sun.

Diagram shows the relationship between the dusty orbital path of a comet and the Earth's orbit. When Earth passes through where the two orbits intersect, we can experience a meteor shower. In some cases, the same comet can produce two different meteor showers when the orbits intersect at two places. (NASA)

When Earth plows through the comet trail, the dust grains encounter our planet&rsquos atmosphere at speeds of 20 or more miles per second and burn up in a flash. The meteor streaks you see are located 40 to 50 miles above the Earth&rsquos surface. Meteor trails can be very bright and, because the dust grains travel so fast, the trails can be very long. But each meteor is only a small fleck of rock or metal, usually no larger than your fingernail.

Unlike most showers, the Geminids&rsquo dust trail was left behind by an asteroid, named 3200 Phaeton .

A radio image sequence shows the rotation of the "rock comet" 3200 Phaeton, the parent asteroid of the Geminids meteor shower. These images were captured in 2017 when 3200 Phaeton, a 3.6-mile-long asteroid, came within 6.4 million miles of Earth. (Arecibo Observatory/NASA/NSF)

This asteroid, of a variety sometimes called a &ldquorock comet,&rdquo orbits the sun once every 1.4 years. When it gets close to the sun and is warmed by its rays, frozen volatile materials (mostly water ice) in the asteroid evaporate and blow off into space, carrying bits of dust.

As you wait for the thrill of the next meteor to cross the sky, think about this: that bit of rock or metal of each meteor spent the last five billion years or so drifting randomly around the solar system or riding inside a comet or asteroid. Then, flash! It&rsquos gone. And you saw it.


The Geminids are quite colorful

The colors produced by the Geminids are among the most beautiful. These meteors appear to glow white while they can also appear yellow, blue, red, and green.

This meteor shower was first discovered in 1862, but its parent asteroid 3200 Phaeton wasn’t identified for almost another 150 years, in 1983. The Geminids appeared shortly before the U.S Civil War, but they received little attention since the shower was weak. Nothing hinted at the fact that the Geminids would become a major display in the sky.

Recent observations estimated that around 85% of Geminids burn up at approximately 40 to 55 miles above Earth’s surface, and around 15% of them get below 40 mi altitude.

They go deeper into the atmosphere than the Perseids because they are moving slower – at 78.000 mph while the Perseids are at 130.000 mph. Another reason for their greater descent is the fact that they are made up of denser materials.


The Leonid Meteor Shower Explained

Every November the region of the night sky associated with the constellation of Leo is filled with a prolific meteor shower, known as the Leonids. The Leonids generally occur each year between November 13th and November 21st, and is one of the 10 biggest meteor showers of the year. The shower reaches its peak on around the 17th, when 20 to 30 meteors can be seen each hour. However, every 33 years a periodic meteor storm occurs when thousands of meteors can be observed every hour, the next of which is due to occur in 2032.

Meteoroids, Meteors, Meteorites

Although the meteors appear to radiate from the Leo constellation , it is in fact caused by the Earth intersecting a trail of dust left behind by the Tempel-Tuttle comet during its countless journeys orbiting the Sun. As the comet’s trailing debris particles, known as ‘meteoroids’, hit then vaporize in Earth’s atmosphere at around 158,000 mph (256,000km/h), they produce the streaks of light in the sky we call meteors or shooting stars. Most meteoroids are completely incinerated around 60 miles above the ground, but those few making it all the way to the Earth’ surface are known as meteorites.

Biggest Leonids in History

The Leonids have apparently been observed since 902 A.D, a year which Arab historical accounts refer to as the “Year of the Stars,” and Chinese astronomers as the year “stars fell as rain.” However, the spectacular Leonid meteor storm of 1833 is credited with launching the modern study of meteors, and caused such widespread panic in the United States that many people feared that it was the end of the world.

At the time, an incredible two hundred thousand meteors an hour were seen in the November night sky. Such was the Leonids’ intensity that many people were woken from their sleep by what appeared to be the sky on fire or by the commotion coming from the streets. However, all survived the night intact, although they might have better enjoyed the spectacle had they known it was more likely they would be struck seven times in a row by lightning than being hit by a falling meteorite.


Meteor Shower Was a Dud, But Showing Up Was Half the Fun

By: Bob King November 22, 2019 33

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The Alpha Monocerotids happened as predicted, even if not quite as we expected.

Michael Boyle Sr. caught an Alpha Monocerotid speeding through Orion last night. I saw 20 meteors in an hour (not 400) from a dark sky site. But they were faint," writes Boyle.
Michael Boyle Sr.

Astronomy is just so weird. Sometimes you have to take it in stride. After the hype of the Alpha Monocerotids — of which I'm partly to blame — the shower proved to be very weak. Michael Boyle Sr., an amateur astronomer in Florida, an ideal spot from which to view the event, reported about 20 meteors per hour at peak. Others saw a few. I stood in a bitter cold wind for an hour and 15 minutes and saw exactly one.

I can't tell you exactly why the shower was a dud, but it's safe to say our understanding of the Alpha Monocerotids is imperfect despite the fact that the researchers nailed the predicted peak within 10 minutes of the original estimate (5:00 UT vs. 4:50 UT). While the 400 meteors per hour rate was for ideal conditions over a short period of time, the radiant was low for many observers in the U.S., so fewer meteors were expected. Still, I was surprised that I saw almost none. My skies were excellent despite occasional clouds, with the winter Milky Way easily visible. The radiant stood a couple of fists above the horizon. (Nov. 23 update: The count was off by a factor of 5 possibly due to Earth grazing the comet's trail instead of passing directly through it.)

While waiting and watching for meteors, other sights made the outing a special one — including seeing Sirius reflecting on Lake Superior.
Bob King

While astronomers can predict the positions of planets and stars like clockwork, some phenomena remain elusive. The aurorae are a prime example — infamous for either not showing up on time, not happening when they're "supposed to," or appearing unexpectedly.

Native American mythology makes room for nature's unpredictable side by including a character called the trickster, which usually takes the form of an animal. Locally, he's a coyote. The trickster is a supernatural being who likes to mess with humans and break the rules. If you're a skywatcher, it eventually becomes second-nature to allow for a potentially spectacular event to not happen at all. Yes, there is disappointment, but there is often joy in the occasion for the simple reason that you showed up.

Showing up means you invested a part of yourself and time to pay attention to something in that big world out there. In doing so, you've also opened yourself up to experiencing something unexpected. At the very minimum, those who did go out last night got to see Orion and Sirius in all their twinkling glory. I saw that . . . and a little more.

The sky over my house was solidly overcast an hour before the start of shower, but for some reason was clear over the neighboring Lake Superior. I wished for a boat. In lieu of that, I got in the car and drove the two miles down to the lake. Incredibly, a chunk of clear sky hung open in the southeastern sky in the direction of Orion and the shower. Elsewhere clouds hung thickly.

Spectacular shower, right? Nope. What you're seeing is actually a train of F-16 jets flying in a formation over Lake Superior. The bright star is Sirius.
Bob King

I set up a camera, stood in the 20 mph, 20° wind, and watched. I saw a couple of sporadic or unrelated meteors but no shower members until around 10:37 p.m. That's when I noticed what looked like sparks flashing from the radiant (from where the meteors appear to stream), southwest of Procyon, a star near the constellation of Monoceros, the Unicorn.

The sparking continued for several minutes and looked almost exactly like distant fireworks — pop! pop pop! pop! I started yelling crazy "wows" into the wind, thinking this was it, the event we had all hoped for — until I looked around and noticed there weren't any sister meteors plowing across the rest of the sky. That wasn't normal. A couple minutes later the flashes had shifted further west and eventually it became apparent: I was looking at a bunch of airplanes!

We have a national guard air base in Duluth, Minnesota, and the pilots will routinely practice flying at night over Lake Superior and the neighboring state of Wisconsin. I'd never seen so many bunched up so close at a distance. Their flashing lights mimicked head-on meteor flares and created the perfect fake meteor shower with a "radiant" or direction of travel from the southeast of Monoceros.

By 11 o'clock the Big Dipper began to climb the northeastern sky once again.
Bob King

The sole Alpha Monocerotid I saw streaked slowly upward from the Unicorn and sliced across Orion, maxing out around first magnitude. For me, though, the Milky Way was enough, the Big Dipper standing on his handle above wispy clouds, and the roar of waves slapping the rocks below the road where I parked my car.


Meteor Showers

Meteor shower displays are associated with the Earth’s passage through meteor streams. These streams consist of the debris left over from the passage of comets (see diagram to the left for the Leonids meteor stream). As comets pass through the inner solar system, the radiation from the Sun causes them heat up, evaporating the dusty-icy materials of the comet. These particles are left in the wake of the comets passage creating a stream of small debris that is strewn along the comets orbital path. If the orbit of the Earth intersects the orbital path of a comet, then at regular predictable times throughout the year the Earth will pass through the stream of debris creating a meteor shower.

How do I observe a meteor shower?

Enjoying a meteor shower is easy. You need only a site far from the blinding lights of the city. Take with you a lawn chair or sleeping bag, perhaps a blanket or hot chocolate to keep warm, and gaze upward towards the sky. Absolutely no equipment is needed to enjoy the cosmic show. For safety reasons, never observe alone in a secluded place. Meteors come in all brightnesses, sizes, and colors, and there is no way to predict what might appear on any given night. Most will be dim, but some can appear quite spectacular. If our Earth encounters a much larger meteoroid than is common–say, the size of a marble–it might appear much brighter than any of the stars or planets in the sky. We would see its demise as a brilliant smoking or flaming fireball. More than 50,000 fireballs occur in our atmosphere each year, though most are not seen since they occur in daylight, over un-populated areas or open ocean. If a fireball produces a sonic boom, it is then called a bolide. Only about one out of every ten fireballs behaves in this way.

When do the most intense outbursts occur?

Your best chance of seeing meteors comes after midnight and before dawn. The reason for this peculiarity lies in the motion of our Earth. In the hours following sunset, our hemisphere faces the direction opposite our orbital motion–that is, we are on the trailing side of the Earth and are looking out the Earth’s “rear window.” Only those meteoroids that catch up to us at a speed of at least 18 miles per second (29 kilometers per second) can fall into our atmosphere. With clear weather we might see two to six sporadic meteors each hour during early evening. After midnight, however, we lie on the leading side, facing the direction of the Earth’s orbital motion. Now, when we gaze into the sky, we peer out our planet’s “front window” and can see all those particles being swept into the atmosphere “head-on.” The nearer to dawn it becomes, the more sporadic meteors we can expect to see–perhaps as many as 14 per hour-as well as shower meteors.

What is a meteor storm?

Typically, a meteor shower only produces a couple dozen meteors per hour. But, occasionally a meteor shower occurs soon after the comet (whose debris is the “stuff” of the meteor shower) has made a recent visit. As a result, dense pockets of debris are left in the comet’s wake. If the Earth encounters one of these dense pockets of debris, a meteor storm occurs. One of the more famous meteor showers is the Leonids (peaking around mid-November each year). The meteor shower is caused by the comet Tempel-Tuttle with a 33 year orbit. In November of 1966, the last time Comet Tempel-Tuttle swung by our planet and left in its wake a fresh supply of dust, skywatchers were treated to a cosmic extravaganza as meteors fell at the staggering rate of 41 per second! In a typical year, the Leonids produces a meteor rate of about 60 to 100 meteors per hour falling from the direction of the constellation Leo in the eastern sky. However, every 33 years or so, watchers are treated to the show of a lifetime. It’s certainly happened before, perhaps it will happen again.

Why are some longitudes favored?

The meteors in any given shower come from a particular direction in space. You need to be on the hemisphere facing that direction to see the meteors. It also has to be night-time, except for incredibly bright fireballs.

Can damage to satellites occur?

Very high speed impacts of tiny dust grains on satellites can cause plasma to be generated, which can lead to electrical failure. There is evidence that the Olympus communications satellite was disabled owing to the impact of a meteoroid from the Perseid stream in 1993.