Why didn't Leonid Meteor Shower appear last year?
Can we watch the Leonid Meteor Shower on Nov.17 this year ?
Let's see the explanation of Leonid in Planetarium Show.

-- November 17, 1998
-- Beach near Kanazawa Hakkei

It was past midnight but people were not leaving the beach.
Cats wondering around seemed to be surprised by the crowd.

November 17, 1998. It was forecast that the Leo meteor shower could be seen that night, an event that occurs once every 33 years.
Many Japanese people stayed up in early morning hours to see the Leo meteor shower.

The Leo meteor shower is a very special event among enthusiasts of astronomy.

Unlike other meteor showers, you can only see the Leo meteor shower once or twice about every 33 years.
When Leo meteor shower does appear, the shooting stars could be traveling at km up to several hundred thousand per hour.
In other words, more than 30 shooting stars appear every second.
And this wonderful phenomenon continues for several ten minutes.

This rare event every 33 years was supposed to occur tonight, November 17, 1998, but . . .

-- Gradually daylight breaks.

We could not see the meteor shower even after the forecast time.

It was not a total failure. Nearly ten very fast flashing shooting stars, which characterize the Leo meteor shower, could be seen in one hour even from the city.
The meteor shower over the Izu Peninsula at 4:13 a.m. on November 18, was particularly impressive.

The Leo meteor shower observed in Japanese skies last year was far from traditional.
What was wrong with the forecast?

-- Different scene. New paper articles are shown.

Last fall, all of Japan went crazy over the Leo meteor shower.
Amateur astronomers and social organizations held orientations throughout Japan, and books about the Leo meteor shower were available in bookstores everywhere.
The first joint observation involving 238 teams of high school students also took place.

-- Gate of astronomical observatory.

We interviewed the Public Relations Department of the National Astronomical Observatory about the situation last year.

Manager: We were so busy with TV interviews, lecture meetings, monthly interviews, and continuous interviews on the actual day.

Mr. Ono: There were so many inquiring phone calls that we were unable to do any other work.
That is why we urgently created a special dial for the Leo meteor shower.

"Despite all that . . ."

-- Different scene, next day's newspaper.

Headline: "Why Didn't Leo Meteor Shower Appear?"

Why didn't the Leo meteor shower appear?
Before we go any further, let's first define a meteor shower.

-- Caption "What is a meteor shower?" and the explanatory diagram.

The shooting stars are small planets and dust particles which circle the solar system, enter the earth's atmosphere, then burn up due to friction.
They burn up around 100 km above earth and create light.
This is ten times the altitude at which airliners cruise.

Dust particles, which become shooting stars usually weigh only 0.2 g or about as heavy as a paper clip.

-- Photo of meteor shower.

But, is it really possible to clearly see from earth such small particles burning?

-- Explanatory diagram.

In reality, we are not seeing the actual flames dust particles.
Dust particles becoming a meteor shower enter the atmosphere at a speed of several tens of km per second.
Enormous energy is output at this point, the dust particles are decomposed into atoms, and transform into electronic gas called plasma.
What we see as shooting stars is the light of this plasma.
The mechanism of the light of shooting stars was a mystery for a long time, but we gradually discovered the truth thanks to spectral observation.

-- Explanatory diagram under the caption "What is a meteor shower?".

Just many shooting stars appearing is not a meteor shower.
A meteor shower is only when many shooting stars fall from a single point of the sky like fireworks.

-- Explanatory diagram.

Another thing is that, even though it is like fireworks, a meteor shower does not shoot in the small area like this.
It shoots across the entire sky equally.
Therefore, for observation, it is better to be able to see the entire sky.
A telescope that only shows a small area of the sky is therefore useless, and it is best to observe with your own eyes.

(Note: Specialists also use telescopes to observe meteor showers.)

-- Caption "Why does a meteor shower shoot from a single point in the sky?"

How does such a strange phenomenon as stars shooting down from a single point in a constellation occur?

-- Explanatory video.

Now think about when you are standing in the rain.
What do you see when you look up?
It looks like raindrops falling from a single point in the sky.
The same can be said about a meteor shower.

The raindrops appear to fall from the same point directly above you.
This seems radical because all raindrops fall in the same direction.

-- Explanatory diagram on the side.

This is same in a meteor shower.
It seems radical to us when shooting stars fall in the same direction.
For the Leo meteor shower, shooting stars are shooting to us from Leo.

-- Caption "Why can we see meteor showers on the same day every year?" and date chart.

There is another strange point.
Meteor showers can be seen on the same day every year.
Such as around August 13 for the Perseus meteor shower and December 13 for the Gemini meteor shower.

-- Explanatory diagram.

What does this same date implying?
Earth revolves around the sun in one year.
For example, if the earth was at this point on September 1, then the earth would return to the same point on September 1 of next year.
So, seeing a meteor shower on the same date means that we can see meteor showers only when the earth reaches a certain point.

This means that many dust particles at that certain point appear to be a meteor shower.

However, what will happen if certain dust particles stayed at one point?
Those dust particles will be pulled by the sun's gravity into the sun.

What can be done to avoid this?

Dust particles can move around the sun just like the earth and Hally's Comet.
When these particles are moving, centrifugal force will keep they from falling.

In other words, meteor shower is the belt of dust particles revolving around the sun.
We can see a meteor shower when that belt of dust passes across the earth's orbit.

-- Explanatory diagram of circling belt of dust.

Now, how was this belt of dust created?
There is only one type of astronomical body that continuously creates this dust --- comets.

-- Comets go around the orbit of the belt of dust.

Meteor showers are created by the dust particles left by various comets.
The Leo meteor shower is the dust of a comet called the Tempel-Tattle comet.

The cycle of the Leo meteor shower dust orbit is about 33 years, and that of the Tempel-Tattle comet is about 33.2 years.
Both orbits match perfectly.

-- Close up of belt of dust.

There are various types of belts of dust based on the meteor shower.
The left belt is that of the Perseus Meteor Shower which occurs every year, the right belt is that of the Leo meteor shower which can be clearly seen every 33 years.

The Leo meteor shower is a type of meteor shower in which dust particles collect instead of dispersing.

-- Change to a huge diagram with the earth in motion.

On November 17, the earth is moving into the belt of dust.
However, this belt seems to be quite uneven.
If the earth does pass through the dense part of the dust, no wonder that a meteor shower cannot be seen.

Some say that the dense part of this dust is like a twisted ribbon.
Could the earth pass through the dense and very narrow part and still rotate?
This is very difficult to predict.

Actually, for the Leo meteor shower, there were meteor shower in 1966, but not in 1933, even though a big shower was predicted.

-- Caption "How many shooting stars were there in 1998?" and Explanatory diagram.

So, how many shooting stars were there in 1998?
Last year in Japan, the number of shooting stars did not change much from 1:30 am (when Leo appeared) to 4:30 am (when the maximum number of stars could be seen) November 18.
Most people could only see ten shooting stars in one hour.

However, there was a time when several hundreds of shooting stars were observed in one hour.
That was around 11 a.m. on November 17.
The Nobeyama Radio Wave Observatory observed this shower.
This radio wave observation was possible because the plasma created by the shooting stars reflected the radio wave.
However, this large-scale meteor shower in daylight was impossible to observe with the naked eye.

When this large-scale appearance was observed in Japan by using radio waves, it was night time in Europe.
From the European reports gathered by the International Shooting Star Organization, 260 shooting stars was observed in one hour in the area under favorable conditions.
Some reports indicated even move stars observed.

However, 260 stars in one hour is still not a true Leo meteor shower.

-- The skyline of China.

Let's examine the last prediction of a meteor shower and the result.

Records documenting the first sighting of the Leo meteor shower around the10th century were found in China and Europe.
After that, the Leo meteor shower was reported in the historical documents of mainly China and Japan every 33 years.

We can confirm the report on the Tempel-Tattle comet which created the dust of the Leo meteor shower based on the history of the Leo meteor shower.
You can see that the Leo meteor shower makes a big appearance just before and after the Tempel-Tattle comet enters the earth's orbit.

-- The skyline of old America.

However, the Leo meteor shower was unknown to modern Europe.
Perhaps there were no major sightings.
Then in 1799, a major sighting was reported.
If you trust the records of that time, 50,000 shooting stars in one hour, or more than ten stars shot in per second.
Even astronomers did not know what was going on.

In 1833, 34 years later, a big shower was observed in America.
From the way that shooting stars fell and the position of radiation, the mechanism of the meteor shower was understood by the work of Ormstead and others.

-- Table of Leo meteor Shower Sightings.

Astronomers expected to see a wonderful meteor shower every 33 years after that, but the reality is as you all know.
None were observed in some years and only few stars were observed in others (like in Japan last year).
Astronomers learned how difficult it is to predict a meteor shower.

Last year was not a total failure, but in Japan, which reputedly has the most favorable conditions was far from what people excepted.
Only 260 shooting stars were observed in Europe in one hour (where most shooting stars were observed).

So, what will 1999 be like?
Many shooting star specialists are making predictions.
By averaging the various predictions, it seems that 11 a.m. on the 18th is the best time.

It is daytime in Japan, but it is night in Europe, and the conditions are said to be good.
However, like last year, the best time can differ from that of predicted..
If the predicted time does differ, we may be able to see a wonderful meteor shower in Japan.

Now we will have Mr. Kawahata of the Shooting Star Observers Club of Tokyo give us few points about meteor shower.

I will like to talk about a few points about observing a meteor showers.
The time is when Leo is just above the horizon.
It is better without the moon, as dark shooting stars can also be seen.
In 1999, the moon will fall before midnight, so it would be better to observe after that.

For the observation site, it is better to go where there are no city lights and street lights.
City light will reduce the number of stars which can be seen.
Fields and parks with a good view will be ideal.

Regarding the method of observation, it is going to be very cold in November.
Wear warm clothes and lay down.
Your neck will quickly become tired if you observe standing up.
How about observing with several people enjoyably like this?
And last, the prediction of a meteor shower is very difficult.
Please consider yourself very fortunate if you see one.
Please take care when you go.

-- Close up of the skyline of Kyoto or Nara in the Heian era.

In China, shooting stars were called "Tengu-boshi".
The mysterious stars that run across the night sky.
This story came to Japan where Tengu' the monster that flies across the sky at enormous speed, was created.

-- The skyline changes to the Arabian desert, with a mosque in the background.

In Arabia, shooting stars were said to have been sent from the sky to kill the evil monster Jin.
The sky releases a large number of shooting stars to kill the evil Jin in August and November.

November 17, 1999, observation conditions seem good with the moon falling at midnight.
The Leo meteor shower, the desert stones of God used to kill evil on earth.
Are we able to see them?