Category: Meteor Showers

It’s not often that both hemispheres of the Earth get treated to an annual meteor shower, but in a matter of hours the complex Orionid stream is heading to dark sky your way! Where and when do you watch? Will it be as good as this year’s Perseids as filmed by John Chumack above? Try even better! Follow me…

We are now slipping into the stream of Comet Halley and one of the finest meteor showers of the year. If skies are clear tonight, this would be the perfect chance to begin observations of the Orionid meteor shower. But get to bed early and rise well before dawn to enjoy one of the year’s most reliable meteor showers. The offspring of Comet Halley grace the early morning hours as they return as the Orionid meteor shower. This dependable shower produces an average of 10-20 meteors per hour maximum, and best activity begins before local midnight on the 20th, and reaches its peak as Orion stands high to the south about two hours before local dawn the 21st. With only the tiniest crescent of a Moon gone in the early evening, this looks to be the year’s premier meteor shower!

Although Comet Halley has now departed the inner Solar System, its debris trail remains well organized – allowing us to predict when this meteor shower will occur. The Earth first enters the stream at the beginning of October and does not leave until the beginning of November. This makes your chances of “catching a falling star” above average! These meteors are very fast, and although faint, occasional fireballs do leave persistent trails.

For best success, get away from city lights. Face south-southeast in the northern hemisphere and almost overhead in the southern – then relax and enjoy the stars of the Winter Milky Way. The radiant is near Betelguese, but may occur from any part of the sky. The meteor watching experience is much more comfortable if you include a lawn chair, blanket, and thermos of your favorite beverage.

Orionid Meteor Shower – Key Points

• The nights of October 21st and 22nd are the best times to watch.
• Maximum hours rates are typically 20/hr and meteors are described as “fast”.
• The radiant is at RA=06h20m, DEC=+16o, just above the left shoulder of Orion.
• The average magnitude of an Orionid meteor is 3.

Clouded out? Don’t despair. You don’t always need eyes or perfect weather to keep the watch. Tune an FM radio to the lowest frequency that doesn’t receive a clear signal. An outdoor FM antenna pointed to the zenith increases your chances – but isn’t essential. Simply turn up the static and listen. Those hums, whistles, beeps, bongs, and occasional snatches of signals are distant transmissions being reflected off a meteor’s ion trail!

Sky Chart Courtesy of NASA.

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Within hours, the peak of the annual Perseid meteor shower will begin. If you’re worried you’ll be clouded out, then let’s take a look at a different way that you can observe the activity… without your eyes!

Did you know that you can “listen” to meteor showers? If you’re a ham radio operator, then you prize the ionized trails that meteors leave in our atmosphere to allow further signals to “bounce” to more distant receivers. However, you don’t really need complicated equipment to listen to a meteor shower – just an FM receiver and an external antenna. Even your car radio will work!

Place your radio setting on the lowest frequency that doesn’t receive a clear signal and simply listen to the static. When a meteor passes overhead you’ll hear snatches of radio signals from distant stations, pops, buzzes, pings, shrieks, howls, and simple changes in the white noise. Sometimes it’s subtle – and sometimes it’s striking. One thing is for sure, the noises you hear are definitely out of this world! Your equipment can run the gambit from connecting a genuine outdoor FM antenna to an indoor receiver and recording with a tape deck for later playback, to a portable radio. I’ve even used an old television set connected to an outdoor television antenna tuned to channel 3. It’s all fun – and the results are amazing. Here are the dates for the 2009 Perseids.

To open the public’s eyes to just how easy radio meteor listening can be, astrophysicist Chris Lintott will be doing a presentation live in Trafalgar Square on August 14th, 19-20h BST. Chris is a co-presenter of the BBC’s “The Sky at Night” astronomy programme, and is a lecturer at University College London and the project he’s about to take part in is very unique… The Fourth Plinth.

This summer, sculptor Antony Gormley has invited the world to help create an astonishing living monument. He is asking the people of the UK to occupy the empty Fourth Plinth in Trafalgar Square in London, a space normally reserved for statues of Kings and Generals. They will become an image of themselves, and a representation of the whole of humanity. Every hour, 24 hours a day, for 100 days without a break, a different person will make the Plinth their own.

Because of the appalling levels of light pollution in London, Lintott remembered a radio-meteor demonstration given by Andy Smith of G7IZU Radio Reflection Detection and his friend David Entwistle for “The Sky at Night” a couple of years ago, and wanted to do something along those lines. Since no power or wiring are allowed on the Plinth, Chris will be utilizing a recording done by Andy beginning tonight… a talent he’s quite good at! For every hour from midnight on, G7IZU Radio Reflection Detection will be recording the Perseid event and sending Chris the most active hours as MP3 files. He’ll then play these
to the masses over an amplified speaker while holding up photos of how it all works.

If you’re interested in the live radio-meteor/astronomy demonstration, you can access a live video of the Fourth Plinth – and be sure to join them on August 14th, 19-20h BST for Chris Lintott’s presentation!

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Are you ready for this year’s Perseid Meteor Shower? What will be the best place to watch and when will be the best date to see the most “shooting stars”? Follow along and let’s find out…

The Perseid meteor shower has a wonderful and somewhat grisly history. Often referred to as the “Tears of St. Lawrence” this annual shower coincidentally occurs roughly about the same date as the saint’s death is commemorated on August 10. While scientifically we know the appearance of the shooting stars are the by-products of comet Swift-Tuttle, our somewhat more superstitious ancestors viewed them as the tears of a martyred man who was burned for his beliefs. Who couldn’t appreciate a fellow who had the candor to quip “I am already roasted on one side and, if thou wouldst have me well-cooked, it is time to turn me on the other.” while being burned alive? If nothing else but save for that very quote, I’ll tip a wave to St. Lawrence at the sight of a Perseid!

While the fall rate – the number of meteors seen per hour – of the Perseids has declined in recent years since Swift-Tuttle’s 1992 return, the time to begin your Perseid watch is now. The random rate has already increased sharply and there is no guaranteed that skies will be clear on the predicted peak time – traditionally August 12 at approximately 11:00 GMT. The tears of St. Lawrence are already beginning to fall! Let’s join John Chumack via his Northeast Sky Camera #2 in his backyard Observatory in Dayton, Ohio, USA, for a look. This 5 hour movie was compressed to 10 seconds for web viewing.

Says John, “The brightest one occurred when the radiant was low on the horizon around 1:27 a.m. This fireball was at around -8 magnitude or greater, even with all the strong moonlight, some of the meteors are very bright! This one had a double explosion too!”

Astronomers are now estimating a double peak this year for viewers in the eastern portion of North America on Wednesday morning the 12th of August 2009. One peak should occur around 1:00 a.m. EST and the other peak around 5:30 a.m. EST. However, let’s assume that not all of us can be in that place and be up at that time… So let’s take a more practical look at observing the Perseid Meteor Shower.

Perseid meteor activity begins about midnight no matter where you live, but they can happen earlier, too. Because we are also contending with a Moon which will interfere with fainter meteors, the earlier you can observe, the better. There is no harm in beginning Tuesday night before the Moon rises. The general direction to face will be east around midnight and the activity will move overhead as the night continues. While waiting for midnight or later for activity to pick up to begin isn’t a pleasant prospect, by then we are looking more nearly face-on into the direction of the Earth’s motion as it orbits the Sun, and the radiant – the constellation of the meteor shower origin – is showing well. However, it won’t be long until the Moon also begins to show very well, indeed! Put an obstruction such as the edge of a house or a tree between you and Selene… Even if you just open an umbrella, the very act of shielding some of the light will most certainly help you to see far more meteors than if you don’t. For those of you who prefer not to stay up late? Try getting up early instead!

How many can you expect to see? A very average and cautiously stated fall rate for this year’s Perseids would be about 30 per hour, but remember – this is a collective estimate. It doesn’t mean that you’ll see one every two minutes, but rather you may see four or five in quick succession with a long period of inactivity in between. You can make your observing sessions far more pleasant by planning for inactive times in advance. Bring a radio along, a thermos of your favorite beverage, and a comfortable place to observe from. The further you can get away from city lights, the better your chances will be. If you’re cloud out on the peak date, don’t stop watching – because activity continues on for several days!

Will this 2000 year-old meteor shower be a sparkling success or a total dud? You’ll never know unless you go out and try yourself. One thing we do know is the Perseids are one of the most predictable of all meteor showers and even an hour or so of watching should bring a happy reward! Wishing you clear skies and good luck…

On Sunday, March 22, two meteor showers will grace the dark evening sky – the Camelopardalids and March Geminids. Would you like to learn more about what makes them special and why? Then let’s head out into the dark…

We’ll start first with the Camelopardalids. These have no definite peak, and a screaming fall rate of only one per hour. They do have a claim to fame however – these are the slowest meteors known – arriving at a speed of only 7 kilometers per second and activity has been historically recorded on this date. Any bright streaks you might see belonging to the Camelopardalids will appear to emanate from the north. While this might seem rather boring, any member of the Camelopardalids you might spot are anything but boring. “A search for parent bodies for 22 short-period meteoroid streams with an account of long-period planetary perturbations was carried out. Five minor body complexes are found among short-period comets, Earth-crossing asteroids and meteoroid streams.” say Y.V. Obrubov, “There are ten members in the major complex : two comets, P/Schwassmann-Wachmann 3 and P/Pons-Winnecke ; four asteroids, 1984 KD (3671), 4788 PL, 1987 SJ3, 1987 PA…” So where does the stream for the Camelopardalids fit in? Try possibly asteroid Amor (1221) and/or asteroid Selevk (3288) as part of Complex 5.

1221 Amor is the namesake of the Amor asteroids – a group of near-Earth asteroids whose orbits range between those of Earth and Mars. Amor-types often cross Mars orbital path, but not Earth’s. However, on March 12, 1932, Belgian astronomer Eugene Delporte photographed Amor as it approached Earth to within 16 million kilometers (about 40 times the distance from Earth to the Moon). This was the first time an asteroid was witnessed so close to Earth and became our virtual wake-up call to potential hazards. Not surpising, 3288 Selevk is also a planet crossing asteroid, too. According to Obrubov’s research there are 22 meteoroid swarms from bodies with orbital period of less than six years that could account for up to 104 meteor showers – 72 of which have been confirmed either photographically or by radar. “The Camelopardalids has a twin – the Gamma Aurigids.” says Obrubov, “We may therefore assume that the remnants of the parent bodies have been found for two more meteor showers. The existence of complexes of minor bodies again raises the question of the possibility of the simultaneous existence of active comets and products of disintegration – meteoroid swarms and possibly asteroids of the Apollo, Amor and Aten groups…”

So, now we have meteors possibly coming from an asteroid, but what about the other meteor shower that occurs tonight? That’s right… the March Geminids. These were first discovered and recorded in 1973, then confirmed in 1975. With a much improved fall rate of up to 40 per hour, these slightly faster meteors will greatly increase your chance of spotting a shooting star. Like the Camelopardalids, the March Geminds are slower than average – but what causes them? Let’s turn to the work of Miroslav Plavec for an answer:

“In 1947, Whipple published new elements of the Geminid meteor shower, obtained photographically. An extremely short period, 1.65 years, moderate inclination and considerable eccentricity together make the orbit of this shower an extraordinary one both in comparison with comets and with minor planets. But, according to Hoffmeister, the existence of similar meteor showers seems to be indicated. Such a short-period meteor shower as the Geminids presents new aspects in meteor astronomy. Planetary perturbations are likely to play a great part in its nature. The study of secular perturbations is especially important, both in investigating the connection with comets, and also from the observer’s point of view; for example, Adams’ classical work on the Leonids.”

So, when do you start watching? Just as soon as the sky is good and dark at your local time. Use your own best judgement on where to loosely face based on the position of both Camelopardalis and Gemini at the time of your observation. (For most northern hemisphere locations, I would simply suggest facing roughly north and focusing your attention overhead.) Grab a friend, a blanket, a thermos… take your notes and a timepiece, too.

You can make an important contribution by observing when possible. Since the shower wasn’t reported until 1973 and confirmed by a high rate of activity 2 years later, scientists aren’t really sure if the Earth had passed through that particular particle stream until that time. By observing and reporting, even to sources like Universe Today, you are providing an invaluable Internet record to help determine if the stream is genuine. It the March Geminids truly are a viable annual shower, this trail might lead to an undiscovered comet.

If you wish to report your findings elsewhere, please visit the Association of Lunar and Planetary Observers (ALPO) and locate the meteor observing tab. In these pages you will also find links to information from the North American Meteor Network (NAMN), and other things to assist you like charts to understand the meteor’s magnitude, the limiting magnitude of your location, and details for recording what you see and how to fill out an observation report. While it’s certainly true you may see absolutely nothing during an hour of observing, negative observations are also important. This helps to establish if the March Geminids should be considered an annual shower or not. You may also just happen to step outside at the right time and see a flurry of activity as well. Just remember…

When opportunity knocks, you’ve got to be there to open the door!