This document contains my observations of the Leonid meteor shower, collected over several years.
I got up early this morning again to check out the Leonids. Contrary to the impression I got from the weather forecasts, the sky conditions this morning were excellent. The sky was much better than yesterday morning. I used the IMO's technique for estimating limiting magnitude. In particular, I counted stars in designated regions of the sky and looked up my counts in the tables provided by the IMO. Using this method I found a limiting magnitude this morning of around 6.0 to 6.1 in the region of Leo.
My first session this morning started around 3:45am and ran until 4:35am. After that I went in to warm up a bit. The outside temperature was -3C. I then went out again from about 5:15am to 5:45am. After that the twilight was strong enough to convince me to go in. The limiting magnitude had dropped to 4.0 or so in the region of Leo by 5:45.
The Leonids made a magnificent showing this morning! During my first session I counted 207 meteors in 50 minutes. Many of the Leonids were faint, but many were also quite bright. Several exceeded the brightness of Venus. On two occassions I missed the meteor itself, but I was aware of it because the ground around me flashed from the meteor's light. When I was able to directly observe a particularly bright meteor I noticed that they tended to end with brillant flashes of light. In one case, the meteor continued (more faintly) after the flash. I got the impression that the meteor had exploded and a fragment was still burning afterwards. There was no sound.
All of the bright Leonids (magnitude zero and brighter) left obvious trains that sometimes took a second or two (or longer) to fade. I observed some of these in binoculars. They looked like long tracks of fuzz that drifted laterally due, I assume, to high altitude winds. The brighter the meteor the more dramatic the train. Some were even visible to the naked eye for nearly a minute.
I noticed that many meteors appeared quite far from the radiant. It was common to observe them over 90 degrees away. I did most of my observing this morning in the field across the street from my house it was wise that I did so. I was able to see many more meteors with a larger view of the sky than I could have in my yard. Even so, I wasn't able to look at the whole sky at once, of course, and so I'm sure I missed many meteors.
On two occassions I saw a bright interloper. The non-Leonids were slower and moving in the wrong direction. Yet the two that I saw were also quite bright (one was very red).
During my second session the activity level of the shower was even higher than it had been 30 minutes before. I estimate that I observed 10-15 meteors per minute (or up to 900 per hour observed). At times I could see one meteor per second for 10 seconds at a time. It wasn't unusual to see 2 or 3 meteors simultaneously. At one point I saw five at once! If I faced the radiant and held my gaze steadly on Leo, I could see meteors radiating out from the constellation—sometimes several at a time. The effect was quite amazing. This was definitely the most active shower I've yet observed.
Despite the high rate of meteors I would not say that I observed a storm. I could easily see a person going about their normal business and missing the show entirely. How many people look at the sky when they get in their cars to go someplace? Even if a person did a glance quickly upwards he or she might not see any meteors. Even if a person saw one he or she might not think much of it by itself. However, to an amateur astronomer it was definitely an impressive showing.
I got up early this morning to take advantage of the clear weather and to check out the Leonids. Although the predictions are mostly all saying that tomorrow morning will be the best time for the meteors, I wasn't as confident about the weather forecast for Sunday morning. I will get up again early tomorrow if the weather holds up.
I was outside by around 4:00am and observed until a bit after 4:30am. The temperature was around -2C. I was dressed with medium weight clothing and I felt fine for the time I was outside. However, a longer session in -2C would probably require heavier clothes than I was using this morning.
Initially the sky conditions were acceptable, but not great. I could see haze surrounding bright objects like Jupiter and the brightest stars. In my binoculars, haze around even second magnitude stars was obvious. Certain sections of the sky were quite poor—particularly the west. The area of the Leonid radiant, however, was in decent condition. Although the faintest stars normally visible on an excellent night were washed out, the limiting magnitude was probably around 5.0 anyway. I didn't make a formal observation of limiting magnitude, but I probably should have. Perhaps I will print out the necessary charts today to have them on hand for tomorrow morning.
During my time outside I saw one meteor that was probably a Leonid. It was somewhat faint, fast moving, and radiating from Leo. I saw two other random meteors unrelated to the shower (moving in the wrong direction). I should note that although I did spend a fair percentage of my time watching the Leo area, I also spent time working sections of the sky with the binoculars, and viewing other regions with my naked eyes. This wasn't a serious, formal Leonid session. However, I can conclusively say that the amount of Leonid activity this morning was quite low. I believe that I would have noticed more meteors if the ZHR had been anything significant—even by ordinary shower standards. Hopefully I'll have a chance to observe the area again tomorrow.
By the end of my session the sky conditions were degrading rapidly. Very obvious fuzz was visible around the stars in Orion in the west and the Hyades and Pleiades clusters in Tau were nearly invisible. The limiting magnitude in Leo was maybe around 4.0. Since it didn't seem like I would see many Leonids and since the sky conditions would have made hunting deep sky objects in my binoculars very difficult, I ended up coming in earlier than I expected.
Here are some links to other pages about the Leonids.