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THE LEONID METEOR SHOWER has come and gone! The deluge of reports that poured into Sky & Telescope's office over the last few days has now dwindled to a trickle. If not for these reports, S&T's editors wouldn't have much to say about how the shower went, because -- sob! -- we were 100% clouded out.
More fortunate observers all over the world tell the same story: this year's Leonids were rife with dazzling fireballs, many so bright that they cast shadows. Long-lasting trains were common. Many skygazers counted meteors at rates exceeding one a minute, though the hoped-for "meteor storm" with rates of many meteors per second never materialized -- despite some reports to the contrary (see the end of this article for an explanation).
Here are excerpts from some of the Leonid e-mail we've received, in chronological order as the zone of the shower's visibility swept westward around the world over the past two nights:
Rob McNaught Great display from 17:00 - 19:40 UT Nov 16. About half of negative mag
and many good fireballs. Brightest around -14. Rates about 1 per minute.
Saw a few sky flashes from fireballs that were below our 1 degree horizon!
Rates lower than the 1993 Perseid max from S. France, but the number of
fireballs was higher. Overall, the most amazing shower I've seen and I've
been awaiting this for 32 years.
Chinese and Dutch observers in the Sino-Dutch Leonid Expedition observed
strongly enhanced activity of the Leonid meteor stream between 17:35-22:50
UT, from central China [24 hours before the predicted maximum]. The enhancement
included a spectacular number of fireballs. From 489 Leonids observed
by M. Langbroek between 19:22-22:50 UT (limiting magnitude about 6.7),
41 were brighter than magnitude -3 with several in the -8 to -12 range.
A preliminary Zenithal Hourly Rate calculation gives... 150 or 160 for
19:22-22:50 UT Nov. 16.
Warm greetings to everybody from COLD Russia!!! With -15.5 degrees C,
I couldn't bear it for more than twice an hour, but still I saw 71 Leonids
under VERY poor conditions.
I started observing at 2:00 a.m. local time and the show was already
going on at its best!.... I had to watch from a park inside city limits,
with lots of clouds from east to west. I'm afraid I lost 70-90% of possible
meteors due to this; the limiting magnitude was hardly 3.5.... An amazing
sight was at 2:37 local time (23:37 UT) when a -3 Leonid left a five-arcminutes-wide
train which was seen through the clouds for more than 25 seconds, slowly
changing its shape.
Back home I fixed myself a cup of coffee and sat by the window just
when the radiant was seen through it. The field of view is restricted
by an 8-story building in front of me; only 20 x 60 degrees of the sky
can be seen. To my surprise I've spotted 12 Leonids in 45 minutes through
the double window glass which wasn't washed for a few months.... Was soon
outdoors again!
Just got back in from a brief look at the sky... and the show is still
going on...! Even though it's rather cloudy -- not thick cloud, low, misty
stuff leaving tantalising gaps -- the meteors are visible through the
cloud, travelling very quickly, many of them ending with terminal flares
and bursts. I just saw three magnitude -7 fireballs in the space of 5
mins, and one amazing -9 or so fireball which ended in a flare which lit
up everything... Even in the areas completely hidden by cloud there are
flashes and burst of light, making the sky look like there's a WW2 artillery
bombardment going on, unbelievable, truly spectacular.... The meteors
are travelling far, far quicker than I expected; if you think you're going
to be able to follow them in binoculars, you're wrong, they're faaaaaaaaaaaast!!!
For telescopic [meteor] observers like myself [who monitor a shower's
very faintest meteors with optical aid] tonight was a major disappointment.
Where were the faint meteors? The incessant flashes of fireballs -- some
coming just seconds apart -- were a great distraction too. At times I
lost my night vision thanks to the -12 or brighter events peppering the
sky. Then there were the demands to turn the 'scope on to the long duration
trains (some as long as 20 minutes). To be fair, it was an awe-inspiring
sight to see crepe paper, hollow spiral trails, and new nebulae in the
sky.
Oh, what a night. The sky was clouded over 95%. Through the holes in
the clouds we observed for half an hour [3:45-04:15 UT Nov. 17). And we
saw the most beautiful meteors we have ever seen. Sometimes the clouds
were beautifully lit up by the fireballs behind them. To give a magnitude
to the meteors is difficult because of the bad weather conditions, but
I say most were -4 and brighter.
I don't have words to say what happened the last night. About 15 of
us on the summits of Gran Canaria, at 0:00 UT Nov. 17, were preparing
our cameras and finishing our preparations when the [shower's radiant
rose and meteor rates began] ascending in moments, fireballs crossed the
whole sky.... Some reached magnitudes of -9, most left a train of several
seconds and the most brilliant with trains 5 minutes visually. As the
radiant rose higher in the east we observed bigger activity, for moments
we were not able to record our count because even in intervals of 2 seconds
we saw up to 6 meteors. Until dawn the activity maintained, with some
ups and downs, but always characterized by fireballs.... From 0:30 to
6:00 UT [one observer] counted about 800 meteors.
I am too Leonid-flashed to compose a coherent paragraph.... [Summary:
in 3.89 hours from 2:00 to 6:17 UT, naked-eye limiting magnitude 6.1,
counted 733 Leonids.]
From 1:50 to 2:37 a.m. Eastern Standard Time [6:50 - 7:37 UT] I counted
54 Leonids (and 5 non-Leonids) in a sky mostly free of clouds (zenith
limiting magnitude maybe as good as 6.0), then in the final 13 minutes
of the hour with clouds rolling in, another 13 Leonids. During the hour
three apparently cast shadows, and there were about 5 or 6 lesser fireballs.
One of the brightest flashed off and on like lightning as it passed high
in the north. Only a few Leonids left trails which lingered 10 to 20 seconds
(as if that's bad!), but one was visible to the naked eye for 8 or 9 minutes!
Most of the bright Leonids were bright yellow but a few were blue, including
one of the very brightest.
What a night! In 32 years of observing meteors showers, this is the
brightest display that I have ever seen. A lot of fireballs and it was
not unusual to see more than 5 Leonids in only one minute. The display
was strong all the night.
The weather was not very good. It was variable sky, with periods of
overcast. Only the last hour of observation (05:15 to 06:15 EST) offered
clearer sky. Limiting magnitude was between 2.5 and 5.0 with most of the
time near 3.5.
I observed the Leonids for a brief hour Tuesday morning (between 3:15
and 4:15 a.m. EST) and, despite at least 50% obscuration from clouds &
fog, witnessed 2 meteors per minute right up until the sky completely
clouded over! Several fireballs displayed bright green and violet....
Never before have I seen a meteor shower that made me scream and squeal
with such delight!
I was seeing meteor rates of near 100 per hour off and on this morning.
I was seeing better than 300 PER HOUR THROUGH DENSE FOG after 5AM CST.
This was only the fireballs and doesn't even count the fainter ones....
Just came in to warm up. My feet are frozen. So far have observed for
3 hours Teff under nice clear skies -- limiting magnitude
6.0. SIMPLY UNBELIEVABLE!!! At times rates as high as 5-6/min. Fantastic
fireballs illuminating the horizons. Geese on the lake going nuts. I've
never seen anything like this before in my life!!!
I headed for the countryside at 3 a.m. Central Time and watched the
skies for one hour. We counted over 100 meteors including more than 50
fireballs. The fireballs left streaks of green, yellow, pink, and red.
Two lit the sky so one could see the surrounding countryside.
The meteors were streaking from every direction.... We witnessed one
spectacular pink fireball on the southern horizon that lit up the sky
as if lightning had flashed.
I have watched a number of meteor showers but nothing compares. I will
never forget the Leonids of 1998!
I was looking east and the trees nearby turned blue. I turned around
and saw the persistent train left from the fireball. It was about 1:45
CST + or - 15 minutes. The best one I saw left a train that lasted for
about 30 minutes. There seemed to be more fireballs at around 7:00 - 8:00
UT than around 11:00 -12:00 UT. The rate was around 60 per hour here in
central Missouri. There is light pollution and light ground fog, but limiting
magnitude was around 4.5.
Observing at Anderson Mesa with Brian Skiff, Bill Ferris, Chris Stubbs,
and Gene Magnier. Bill's counts peaked out at 12 Leonids in 8 minutes
from 11:40 to 11:48 UT. Mine peaked out at 19 Leonids in 12 minutes from
11:52 to 12:04. Two meteors of magnitude -5 were seen... one at 12:25
a.m. local time was 140 degrees long, leaving a train that hung around
for 10 minutes and got quickly kinked by the upper-atmosphere winds....
There were lots of foreshortened ones in the head of Leo that we figured
should be called Puff Daddies because they're just these short puffs.
I woke up around 04:20 local time. Sky mostly clear. In 15 minutes,
I only observed 4 small Leonids, trains lasted less than one second. Where
are all the fireballs? Send them this way!!
Observed 4:15 - 4:40 a.m. Pacific time (12:15-12:40 UT) with 70% of
the sky obscured by clouds. Naked-eye limiting magnitude was 4. Saw only
4 Leonids thru moving holes about the size of Orion. Mags: -2, -1, 0,
1. Cloud cover was thin enough that really bright fireballs would have
been visible thru them. Clearly not the level of activity seen earlier
in the day. Completely cloudy now and raining again. Well, at least I
saw a few....
Observed from 8:30 - 13:05 UT from Holbrook, AZ. I saw numerous bright
meteors with long persistant tails. At 12:48 witnessed a -10 mag. fireball
that left a train for 10 mins. That was the brightest... never saw any
-11 thru -15, but am thankful for the clear skies. I saw two stationary
meteors near Algieba in Leo near radiant of about -1 magnitude.
High thin clouds rolled in about 12:00 UT....
It did seem to slow down after 11:00 UT for some reason... I was seeing
on an average of 1 per minute before that time. I wasn't as impressed
with the number of meteors, but the quality was excellent.
I joined the Las Vegas Astronomy Society at Nelson's Landing near Boulder
City. Boy was I glad I did! By midnight local time we were seeing Leonid
fireballs and numerous Taurids. Local peak was between midnight and 2:00
a.m., when we were seeing approx. 300 meteors per hour! Sometimes there
were 3 or 4 in the sky at a time! Some fireballs streaked over 130 degrees
of arc. Most were green, with some white and blue.
I observed more meteors last night than in the rest of my 45 years combined.
Many LVAS members told me the same. I also saw the 50 or 60 largest meteors
of my life! The LVAS members counted and timed between 1:00 and 1:10 a.m.;
the count was 36 meteors, which works out to 216/hour. This was by no
means the peak time.
Over 100 people were observing at this location, oohing and ahhing with
each fireball. After Leo rose well above the horizon, the trails grew
shorter but were still spectacular.
George Zay and I drove east nearly to the Arizona border; the skies
were still partly cloudy but better than home. We started counting at
11:00 pm local time (even before) Leo was above the horizon. We were rewarded
5 minutes later with two beautiful Leonids that shot overhead and disappeared
low in the western sky. These long beautiful meteors continued for the
next half hour at a rate of one every two minutes. These meteors were
bright orange, often with a dim halo, and their tails were bluish. As
Leo rose these meteors became shorter and shorter. Between midnight and
1 am rates increased to an average of one per minute. The next two hours
produced 91 and 104 Leonids. High clouds began drifting in after 3 am
and we were forced to quit at 4 am. The last hour produced 88 Leonids
under thin cirrus.
Although this morning's display lacked the brilliant fireballs we saw
the previous morning, there were still many bright meteors to be enjoyed.
There were often bursts of 2 and 3 meteors all going in different directions
just seconds apart. This show is what I had wildly hoped for but never
really expected to see.
Travel to the Mount Wilson summit was rewarded with a spectacular show:
not so high a rate (several easily visible per minute) but many very bright
and various colors. One very bright event at about 4:40 am PST left a
train visible in excess of 5 minutes (most likely kept illuminated by
imminent sunrise!).
We saw a Perseid-strength max between 11:00 - 14:00 UT on the West Coast.
It was interspersed with very bright meteors... a high proportion of fireballs
in the -2 to -6 range... possibly a few bursts to -8 or so, but how do
you really gauge those mega-ones? I did not see any of the ultra Moon-like
mags reported from California on the morning of the 16th. The proportion
of fireballs certainly was memorable, better than any Perseid display
I've seen.
However, we did not see anything like 90% fireballs as seemed to be
the case in the California report. We saw lots of fainter guys too. In
all, a well balanced show punctuated with fabulous ORANGE fireballs that
left AQUA trains behind them. As the winds aloft "compacted" the two or
three brightest meteor trains, after about 30 seconds or so they looked
like oversized M31's to the naked eye.
Aloha! David Levy, his wife Wendee, Bill Harby, and I watched the Leonids
from midnight to dawn -- starting from 7,000 feet elevation on Mauna Kea,
then to the 12,000-foot level, then to the summit at nearly 14,000 feet.
We were dodging a rising mass of clouds and got snowed on at the summit
at dawn.
We successfully avoided the clouds and had very clear skies the entire
night. Here is a synopsis.
I've been waiting all night for dense cloud to lift and have now 20.00
UT (4.00 HK time) been rewarded by very clear visibility in 25% of the
sky. However, now only seeing about 5 meteors an hour, and rather average
ones. I had a better time of it last night around the same time (20.00
UT), when the count was 75 an hour, with most as bright as 0 magnitude,
and about 25% above -2, and a few above -8.
I'm wondering, as this morning I was watching just an hour after the
predicted peak, whether the peak prediction was too late. As I said, things
where hotter 24 hours ago, and reports from around the world tend to be
most exciting from the US and Europe.
Observed 10:30-15:42 UT Nov. 17th from Dillingham Airfield, Oahu, Hawaii.
I saw 226 Leonids during this interval. The limiting magnitude was around
6.5, with the cloud coverage varying from 0% to 100%; probably around
50% averaged over the whole period. [Note: This suggests that the unobstructed
observed rate would have been about 85 meteors per hour.] There was no
sign of any increase in activity during the last hour before dawn.
Sadly we saw very little... The sky was almost perfectly clear at midnight
but became steadily worse as sunrise approached. There were about 50 people
on the roof deck of Manila Observatory. So any meteor had little chance
of being missed. We saw 6 in three hours.
There was a decided decrease in the the average magnitude from the previous
night. The rates were slightly lower, but the relative paucity of fireballs
compared to Nov 16/17 was a little disappointing.
Results from central India (80.5°E, 26°N) were not good last
night. During 6 hrs of observation -- 00:00 midnight (18:30 UT) to 06:00
morning (00:30 UT, 18th Nov) -- we could see only 60 Leonids. The sky
was partly cloudy. Over 15 of them were bright fireballs mostly white
to yellow or blue.
Only a handful of Leonids between 22:30 UT and 00:30 UT this night.
Sky almost as good as yesterday: limiting magnitude around +5.5, no clouds.
Yet in what must have been around 1.5 hours effective, I only saw a few
Leonids.
We have obtained the following Leonid zenithal hourly rates (based on
one-hour time intervals) from independent observations carried out at
Teide Observatory (Tenerife, Spain):
Interval (UT) No. ZHR 01:26-02:36 20 110* 03:24-04:24 35 65 05:26-06:25 31 55 *radiant at only 10 degree elevation!The limiting magnitude varied between 6.2 and 6.4. Very few bright meteors appeared during the whole observing run.
Went out from 1 to 1:30 a.m. Eastern Standard Time. One night ago at that time the rate was over 1 a minute with many fireballs. Tonight, with the same naked-eye limiting magnitude, FOUR Leonids, all very dim.
I've been looking towards Leo for around the last hour or so, and have seen NOTHING!! There are light scattered upper level clouds, but enough holes, and thin enough that anything +1 or brighter would show.
And two final notes from the editors of Sky & Telescope:
Clear skies!
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