Leonids 2011: visual data quicklook

Introduction

This page shows automated results of the Leonids 2011, based on visual observations by volunteers astronomers collected through the report form of the International Meteor Organization (IMO). The information on this page is generated automatically; for scientific use please refer to manual analyses published in scientific journals (such as WGN). Send your feedback regarding this page to Geert Barentsen.

Page contents:

Page generated: 2011 November 17 at 9:00 UTC.

Activity profile

The graph below shows the ZHR (Zenithal Hourly Rate), which is the number of meteors an observer would see under a very dark sky with the radiant of the shower in zenith.
ZHR_max = 2 based on 6 Leonids reported in 4 intervals, assuming population index r = 2.5

http://www.imo.net/live/leonids2011/out/leo2011overview.png?time=1321520401

The reported intervals are automatically added together into the bins shown above, based on the number of meteors and the distribution of the intervals. For each bin, the following parameters are computed:

• Time is the averaged centre of the reported intervals in Universal Time (UTC);
• Solarlon is the astronomical position of the earth relative to the sun at the above time (equinox J2000.0);
• nINT is the number of reported intervals used;
• nLEO is the number of Leonids observed in those intervals;
• ZHR is the Zenithal Hourly Rate, defined as (1 + sum nLEO) / sum(Teff/C) where Teff is the effective observing time and C is the total correction coefficient for limiting magnitude, clouds and zenith correction 1/sin(h_R);
• Particle density is the approximate number of particles (meteoroids) causing meteors brighter than magnitude +6.5 per billion cubic kilometer (i.e., a cube with 1000 km edge length). The ZHR depends on this density (which can be variable) and the velocity (which is roughly constant) of the meteoroid stream. For more information about the computation method, see the references at the bottom.

Observer statistics

Data has been received from 2 observers in 2 countries. Thank you for your efforts!

Spatial distribution of observers

Note: click on the map for an interactive version.

http://www.imo.net/live/leonids2011/out/world_small.png

Temporal distribution of observers

http://www.imo.net/live/leonids2011/out/leo2011temporal.png

Table of observers

Data access

Create your own analysis. The files below can be opened using Excel:
leo2011_rate.csv (number of meteors per interval per observer)
leo2011_magn.csv (number of meteors per magnitude bin per observer)

Credits and references

The information on this page may be distributed freely provided credit is given to the International Meteor Organization (IMO) and, when possible, to the individual observers. The computer facilities to generate this page are provided by ESA/RSSD and Armagh Observatory.

References:

1. Rendtel J. and Arlt R., editors (2009). Handbook for meteor observations; Chapter 9, Analyses and Calculations. International Meteor Organization. ISBN 978-2-87355-020-2.
2. Koschack R., Rendtel J. (1990). Determination of spatial number density and mass index from visual meteor observations (II). WGN 18, 119-140.

原文：http://www.imo.net/live/leonids2011/