National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
Planets
Leonids
Leonid meteor shower. Credit: Jimmy Westlake
Leonid meteor shower. Credit: Jimmy Westlake

2014 Leonids Forecast
This year the Leonids will peak during the night (after midnight) and early morning hours of 17 and 18 of November (The hours right before dawn are considered the best.). A waning-crescent moon will provide dark enough skies to view these bright and colorful meteors.

Fast Facts

  • Comet of Origin: 55P/Tempel-Tuttle
  • Radiant: Constellation Leo
  • Active: 6-30 Nov. 2014
  • Peak Activity: 17-18 Nov. 2014
  • Peak Activity Meteor Count: Approximately 15 meteors per hour
  • Meteor Velocity: 71 km (44 miles) per second

About the Meteor Shower
The Leonids, which peak during mid-November each year, are considered to be a major shower though meteor rates are often as low as about 15 meteors per hour. The Leonids are bright meteors and can also be colorful. They are also fast: Leonids travel at speeds of 71 km (44 miles) per second, and are considered to be some of the fastest meteors out there.

Every 33 years, or so, viewers on Earth may experience a Leonid storm that can peak with hundreds to thousands of meteors seen per hour depending on the location of the observer.

A meteor storm versus a shower is defined as having at least 1,000 meteors per hour. Viewers in 1966 experienced a spectacular Leonid storm: thousands of meteors per minute fell through Earth's atmosphere during a 15 minute period. There were so many meteors seen that they appeared to fall like rain. The last Leonid meteor storm took place in 2002.

Leonids are also known for their fireballs and earthgrazer meteors. Fireballs are larger explosions of light and color that can persist longer than an average meteor streak. This is due to the fact that fireballs originate from larger particles of cometary material. Fireballs are also brighter, with magnitudes brighter than -3. Earthgrazers are meteors that streak close to the horizon and are known for their long and colorful tails.

Viewing Tips
The Leonids are best viewed starting after midnight. Find an area well away from city or street lights. Come prepared with a sleeping bag, blanket or lawn chair. Orient yourself with your feet towards east, lie flat on your back, and look up, taking in as much of the sky as possible. In less than 30 minutes in the dark, your eyes will adapt and you will begin to see meteors. Be patient -- the show will last until dawn, so you have plenty of time to catch a glimpse.

Where Do Meteors Come From?
Meteors come from leftover comet particles and bits from broken asteroids. When comets come around the sun, the dust they emit gradually spreads into a dusty trail around their orbits. Every year the Earth passes through these debris trails, which allows the bits to collide with our atmosphere where they disintegrate to create fiery and colorful streaks in the sky.

The Comet
The pieces of space debris that interact with our atmosphere to create the Leonids originate from comet 55P/Tempel-Tuttle. It takes comet Tempel-Tuttle 33 years to orbit the sun once.

Comet Tempel-Tuttle was discovered twice independently -- in 1865 and 1866 by Ernst Tempel and Horace Tuttle, respectively. Tempel-Tuttle is a small comet -- its nucleus measures only about 3.6 km (2.24 miles) across.

The Radiant
Their radiant -- the point in the sky from which the Leonids appear to come from -- is the constellation Leo, the lion, near the bright star Regulus. The constellation of Leo is also where we get the name for the shower: Leonids. Note: The constellation for which a meteor shower is named only serves to aid viewers in determining which shower they are viewing on a given night. The constellation is not the source of the meteors.

Also, you need not look only to the constellation of Leo to view the Leonids -- they are visible throughout the night sky. It is actually better to view the Leonids away from the radiant: They will appear longer and more spectacular from this perspective. If you do look directly at the radiant, you will find that the meteors will be short -- this is called foreshortening.

Determine Meteor Shower Activity for Where You Live
http://leonid.arc.nasa.gov/estimator.html

Eyewitness Accounts of the 1966 Storm
http://leonid.arc.nasa.gov/1966.html

Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writer: Autumn Burdick
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> USA.gov
> ExpectMore.gov
> NASA Advisory Council
> Open Government at NASA
Last Updated: 7 Apr 2014