Everything you need to know: Leonid meteor shower

Everything you need to know: Leonid meteor shower

Regulus, the brightest star in the constellation Leo the Lion, dots a backwards question mark of stars known as the Sickle. If you trace all the Leonid meteors backward, they appear to radiate from this area of the sky. This year, in 2015, the planet Jupiter shines in eastern Leo, not far from the Lion's Tail.

Here are all the details you need for 2015’s Leonid meteor shower, peaking on the morning of November 18.

Leonid meteors, viewed from space in 1997. Image via NASA
November’s wonderful Leonid meteor shower happens every year at this time, as our world crosses the orbital path of Comet Tempel-Tuttle. Like many comets, Tempel-Tuttle litters its orbit with bits of debris. It’s when this cometary debris enters Earth’s atmosphere, and vaporizes, that we see the Leonid meteor shower. In 2015, the peak night of the shower is expected from midnight to dawn on Wednesday morning (November 18). The morning before that might be good as well. Although this shower is known for its periodic storms, no Leonid storm is expected this year. The waxing moon will set in the evening hours, so moonlight will not obstruct this year’s Leonid shower. Also, it’ll be fun to look for the bright planet Jupiter, which shines in front of the constellation Leo this year. Follow the links below to learn more:
How many Leonid meteors will you see in 2015?
When should you watch for Leonid meteors in 2015?
Where should you watch the meteor shower?
Which direction should I look to see the Leonids?
Will the Leonids produce a meteor storm in 2015?
Live by the moon! Order your 2016 EarthSky moon calendar today!

Aaron Robinson in Idaho Falls, Idaho captured this photo on November 15, 2015. He wrote: “The Taurid meteors have been overlapping with the Leonid meteors! I have been capturing dozens of them!”
How many Leonid meteors will you see in 2015? The answer of course depends on when you watch, the clarity and darkness of your night sky. This shower has been known to produce meteor storms, but no Leonid storm is expected this year. The Leonids are usually a modest shower, with typical rates of about 10 to 15 meteors per hour at the peak, in the darkness before dawn.
When should you watch for Leonid meteors in 2015? Knowing what time to watch is easy. As with most meteor showers, the best time to watch the Leonids is usually between the hours of midnight and dawn. The expected peak morning is November 18. That’s the morning (not the evening) of the November 18. The morning before might be good as well. Fortunately, the waxing moon won’t jeopardize the view of this year’s Leonid meteor shower.
Where should you watch the meteor shower? We hear lots of reports from people who see meteors from yards, decks, streets and especially highways in and around cities. But the best place to watch a meteor shower is always in the country. Just go far enough from town that glittering stars, the same stars drowned by city lights, begin to pop into view.
City, state and national parks are often great places to watch meteor showers. Try googling the name of your state or city with the words city park, state park or national park. Then, be sure to go to the park early in the day and find a wide open area with a good view of the sky in all directions.
When night falls, you’ll probably be impatient to see meteors. But remember that the shower is best after midnight. Catch a nap in early evening if you can. After midnight, lie back comfortably and watch as best you can in all parts of the sky.
Sometimes friends like to watch together, facing different directions. When somebody sees one, they can call out meteor! Then everyone can quickly turn to get a glimpse.

Regulus, the brightest star in the constellation Leo the Lion, dots a backwards question mark of stars known as the Sickle. If you trace all the Leonid meteors backward, they appear to radiate from this area of the sky. This year, in 2015, the planet Jupiter shines in eastern Leo, not far from the Lion’s Tail.
Which direction should I look to see the Leonids? Meteors in annual showers are named for the point in our sky from which they appear to radiate. This shower is named for the constellation Leo the Lion, because these meteors radiate outward from the vicinity of stars representing the Lion’s mane.
If you trace the paths of Leonid meteors backward on the sky’s dome, they do seem to stream from near the star Algieba in the constellation Leo. The point in the sky from which they appear to radiate is called the radiant point. This radiant point is an optical illusion. It’s like standing on railroad tracks and peering off into the distance to see the tracks converge. The illusion of the radiant point is caused by the fact that the meteors – much like the railroad tracks – are moving on parallel paths.
In recent years, people have gotten the mistaken idea that you must know the whereabouts of a meteor shower’s radiant point in order to watch the meteor shower. You don’t need to. The meteors often don’t become visible until they are 30 degrees or so from their radiant point. They are streaking out from the radiant in all directions.
Thus the Leonid meteors – like meteors in all annual showers – will appear in all parts of the sky.

Old woodcuts depicting 1833 Leonid meteor storm.
Will the Leonids produce a meteor storm in 2015? No. Not this year. Most astronomers say you need more than 1,000 meteors an hour to consider a shower as a storm. That’s a far cry from the 10 to 15 meteors per hour predicted for this year. Still, even one bright meteor can make your night.
The Leonid shower is known for producing meteor storms, though. The parent comet – Tempel-Tuttle – completes a single orbit around the sun about once every 33 years. It releases fresh material every time it enters the inner solar system and approaches the sun. Since the 19th century, skywatchers have watched for Leonid meteor storms about every 33 years, beginning with the meteor storm of 1833, said to produce more than 100,000 meteors an hour.
The next great Leonid storms were seen about 33 years later, in 1866 and 1867.
Then a meteor storm was predicted for 1899, but did not materialize.
It wasn’t until 1966 that the next spectacular Leonid storm was seen, this time over the Americas. In 1966, observers in the southwest United States reported seeing 40 to 50 meteors per second (that’s 2,400 to 3,000 meteors per minute!) during a span of 15 minutes on the morning of November 17, 1966.
In 2001, another great Leonid meteor storm occurred. Spaceweather.com reported:

The display began on Sunday morning, November 18, when Earth glided into a dust cloud shed by comet Tempel-Tuttle in 1766. Thousands of meteors per hour rained over North America and Hawaii. Then, on Monday morning November 19 (local time in Asia), it happened again: Earth entered a second cometary debris cloud from Tempel-Tuttle. Thousands more Leonids then fell over east Asian countries and Australia.

View SpaceWeather’s 2001 Leonid meteor gallery.
Bottom line: If you want to watch the 2015 Leonid meteor shower, just know that the waxing moon won’t substantially interfere on the peak morning of November 18. The morning before, November 17, might be good as well. Find a dark sky location. Plan to watch between the hours of midnight and dawn. Bring along a blanket or lawn chair and spend at least an hour watching. Look for the planet Jupiter near the Leonids’ radiant point. And enjoy!
EarthSky’s meteor shower guide for 2015
Don’t miss anything. Sign up for EarthSky News by email
Easily locate stars and constellations during any day and time with EarthSky’s Planisphere.


Thanks to: http://earthsky.org

Leonid meteors midnight to dawn November 18

• 264
  
• 
  

Tonight for November 17, 2015

Courtesy U.S. Naval Observatory


Tonight – November 17, 2015 – and Wednesday morning before dawn, watch for the 2015 Leonid meteor shower. The predawn hours on November 18 are likely to be the optimum time, no matter where you live on the globe. Will you see what’s shown on the image at the top of this post? Thousands of meteors per hour? No. That image is from 1998, when the Leonids parent comet – Comet Temple-Tuttle – was nearby. The Leonids are famous for producing meteor storms when the comet is in our neighborhood, but no meteor storm is expected this year, only a modest 10 to 15 Leonid meteors per hour.
There’s good news about this year’s shower, though. The moon will set at late evening, leaving dark skies from late night until dawn.
Here’s another tip: the radiant point. As darkness falls in mid-November, the radiant point of the Leonid shower sits below your horizon, as seen from all parts of Earth. As the Earth turns, the constellation Leo the Lion – carrying the meteor shower radiant point – will rise over your eastern horizon around midnight (or around 1 a.m. at temperate latitudes in the Southern Hemisphere). The Leonid meteors are few and far between around midnight, when the radiant point is at or near the horizon. That’s why you’ll see more meteors in the hours before dawn.
Just remember, you don’t have to locate a meteor shower radiant to watch the meteor shower. The meteors will appear in all parts of the sky.
Also, all is not lost in the evening hours! Evening is the best time to try to catch a rare earthgrazer – a slow-moving and long-lasting meteor that travels horizontally across the sky.
EarthSky lunar calendars make great gifts for astronomy-minded friends and family.

Regulus, the brightest star in the constellation Leo the Lion, dots a backwards question mark of stars known as the Sickle. If you trace all the Leonid meteors backward, they appear to radiate from this area of the sky. This year, in 2015, the planet Jupiter shines in eastern Leo, not far from the Lion’s Tail.
What else can you see on the night of the 2015 Leonids peak?
The radiant for the Leonids is near the star Algieba in Leo. This is not Leo the Lion’s brightest star. That distinction goes to Leo’s star Regulus.
Watch for both of these stars. And, during the predawn/dawn hours, look for the line-up of planets in the eastern sky: Venus, Mars and Venus.

Look eastward before dawn to see the grand line-up of planets: Jupiter, Mars and Venus. Click here for recommended almanacs. They can help you know these planets’ rising times.
Both Algieba and Regulus belong to a noticeable pattern on the sky’s dome, in the shape of a backwards question mark. This pattern is called “the Sickle.” The paths of Leonid meteors can be traced backwards to the Sickle pattern, which is a famous asterism – or noticeable star pattern – within the constellation Leo.
By the way, the Leonids are a fast-moving meteor stream. The meteors impact the Earth at some 45 miles per second (72 km/second)! The Leonid meteor shower is known for having bright meteors or fireballs, which can punch into the atmosphere with the kinetic energy of a car hitting at 60 miles per second (nearly 100 km/second).
Bottom line: In 2015, the Leonid meteor shower is expected to be at its best on the night of November 17-18. Usually the most meteors fall in the dark hours before dawn.
EarthSky’s top 10 tips for meteor-watchers
EarthSky’s meteor shower guide for 2014
Donate: Your support means the world to us
Deborah Byrd


Thanks to: http://earthsky.org