Earth Weather / Space Weather

New Meteor Shower?

By: Susie77, 12:34 PM GMT on April 30, 2014


By in
| Human World | Space on Jan 11, 2014



Will Comet LINEAR produce a new major meteor shower in 2014?




The list of major meteor showers hasn’t changed much in recent
decades, but it has changed a little. Meteor showers are part of
nature, after all, and the list of major showers shifts and changes
slightly, as all things in nature do, with one shower or another
becoming more or less exciting as the years pass. In 2014, though, an
exciting new meteor shower might come on the scene. This possible
shower stems from a comet – Comet 209P/LINEAR – discovered in 2004.
Comet 209P/LINEAR passed near the sun in 2009 and will pass near it
again in early May, 2014. On the night of May 23-24, 2014 – if the
predictions hold true – Earth might be sandblasted with debris from this
comet, resulting in a fine display of meteors, or shooting stars.
Mid-northern North American latitudes are favored. Follow the links
below to learn more about the possible 2014 meteor shower of Comet
209P/LINEAR.
What we know about Comet 209P/LINEAR.
Will Comet 209P/LINEAR create a meteor storm?
When to watch, and who is best placed on Earth.
View larger. | Comet 209P/LINEAR on April 25, 2009 as captured by Michael Jager in Austria.  Used with permission.  Thank you, Michael!
View larger.
| Comet 209P/LINEAR on April 25, 2009 as captured by Michael Jager in Austria. Used with permission. Thank you, Michael!
What we know about Comet 209P/LINEAR.
An automated observing campaign, the Lincoln Near-Earth Asteroid
Research project (LINEAR), found this small and somewhat dim comet on
February 3, 2004. The International Astronomical Union gave it the
permanent number 209P on December 12, 2008.
P209/LINEAR is a periodic comet, that is, its orbit around
the sun is relatively short so that we see the comet come close to the
sun again and again. Comet 209P/LINEAR’s orbit brings it near the sun
in just over 5 years. Its next perihelion passage will be May 6, 2014.

The comet itself is not all that exciting. What’s exciting is that
calculations of the orbit of P209/LINEAR indicate that – in May 2014 –
the comet’s debris trails will pass close to Earth. Debris left behind
by the comet may enter our atmosphere and burn up, creating a new meteor
shower.
According to predictions, a little-known comet will pass perihelion in early May of 2014 and, two weeks later, sandblast Earth with dust particles spread along its orbit.  Image by NASA / JPL / Horizons via skyandtelescope.com
Comet 209P/LINEAR will sweep closest to the sun in early May of 2014. Two  weeks later, dust particles spread along its orbit may enter Earth’s atmosphere, creating a meteor shower. Image by NASA / JPL / Horizons via skyandtelescope.com
Will Comet 209P/LINEAR create a meteor storm?

In 2012, meteor experts Esko Lyytinen of Finland and Peter Jenniskens
at NASA Ames Research Center were the first to announce that Earth was
due for a May 2014 encounter with debris from Comet 209P/LINEAR. Other
meteor experts quickly confirmed this prediction and some did use the
words “meteor storm.” The most recent calculations, however, indicate
we might get a strong shower, but perhaps not a storm of meteors.
In 2012, Jeremie Vaubaillon of The Institut de Mecanique Celeste et de Calcul des Ephemerides in France told space.com:
So far,given the observations, we estimate a ZHR
(zenithal hourly rate) of 100/hr to 400/hr, which is an excellent
outburst! But this shower can become an exceptional one. Indeed, given
the current orbit of the comet, all the trails ejected between 1803 and
1924 do fall in the Earth’s path in May 2014! As a consequence, this
shower might as well be a storm.

The more recent, less optimistic calculations come from Quanzhi Ye
and Paul A. Wiegert, both at University of Western Ontario. Their work
was published online in November 2013. In a report on their work at skyandtelescope.com,
John Bochanski wrote that Ye and Wiegert’s work suggests a rate of 200
meteors per hour under ideal conditions. Bochanski wrote:
But Ye and Wiegert warn that, given the current
relatively weak dust production of the comet, rates could be much lower.
With the low dust production, as well as the team’s lower estimate of
how many debris streams from the comet’s previous passes are hanging
around in this region of space, it’s highly unlikely that we’re in for a
meteor storm (1,000 per hour) — although the team couldn’t quite rule
it out.

Will Comet 209P/LINEAR produce a meteor storm, or at least a strong
meteor shower? As with all meteor showers, the only way to know is to
go outside on the night of the predicted peak and see for yourself.
This hemisphere of Earth will be facing into the stream of debris left behind by Comet LINEAR on the night of May 24, 2014. Skywatchers in southern Canada and the continental U.S. will be especially well positioned to see the meteors.  Image via meteor scientist Mikhail Maslov of Russia.  Visit Maslov's website on the new meteor shower here.
This
hemisphere of Earth will be facing into the stream of debris left
behind by Comet LINEAR on the night of May 24, 2014. Skywatchers in
southern Canada and the continental U.S. will be especially well
positioned to see the meteors. Image via meteor scientist Mikhail
Maslov of Russia. Visit Maslov’s website on the new meteor shower here.
The constellation Camelopardalis is far to the north on the sky's dome, close to the north celestial pole.  It's the radiant point of the possible meteor shower from Comet 209P/LINEAR.  Chart via Wikimedia Commons.
The
constellation Camelopardalis is far to the north on the sky’s dome,
close to the north celestial pole. It’s the radiant point of the
possible meteor shower from Comet 209P/LINEAR. Chart via Wikimedia Commons.
When to watch, and who is best placed on Earth. The peak night of the shower is predicted for May 23-24, 2014.
The meteors will radiate from the constellation Camelopardalis
(camelopard), a very obscure northern constellation. Its name is
derived from early Rome, where it was thought of as a composite
creature, described as having characteristics of both a camel and a
leopard. Nowadays we call such a creature a giraffe!
This constellation – radiant point of the May 2014 meteor shower
– is in the northern sky, close to the north celestial pole, making
this meteor shower better for the Northern Hemisphere than the Southern
Hemisphere.
As for the predicted time of the shower … skywatchers in southern
Canada and the continental U.S. are said by the experts to be especially
well positioned to see the meteors on the night of May 23-24, 2014.
Bottom line: On May 24, 2014 – if predictions hold true – Earth
might be sandblasted with debris from Comet 209P/LINEAR, resulting in a
fine display of meteors, or shooting stars. Will it be a meteor storm? Most recent calculations say no, but it might be a strong-enough shower to be thrilling!


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Unexpected Teleconnections in Noctilucent Clouds

By: Susie77, 11:54 AM GMT on April 16, 2014



Unexpected Teleconnections in Noctilucent Clouds


April 16, 2014: Earth's poles are separated by four oceans, six continents and more than 12,000 nautical miles.

Turns out, that's not so far apart.

New data from NASA's AIM spacecraft have revealed
"teleconnections" in Earth's atmosphere that stretch all the way from
the North Pole to the South Pole and back again, linking weather and
climate more closely than simple geography would suggest.
splash

A new ScienceCast video explores unexpected "teleconnections" in
Earth's atmosphere that link weather and climate across vast
distances.  Play it

For example, says Cora Randall, AIM science team member and Chair
of the Dept. of Atmospheric and Oceanic Sciences at the University of
Colorado, "we have found that the winter air temperature in
Indianapolis, Indiana, is well correlated with the frequency of
noctilucent clouds over Antarctica."

Noctilucent clouds, or "NLCs," are Earth's highest clouds.  They
form at the edge of space 83 km above our planet's polar regions in a
layer of the atmosphere called the mesosphere.  Seeded by "meteor
smoke," NLCs are made of tiny ice crystals that glow electric blue when
sunlight lances through their cloud-tops.

AIM was launched in 2007 to investigate these "night-shining"
clouds, to discover how they form and to learn about their inner
chemistry.  As is often the case, however, when exploring the unknown,
researchers found something they weren't even looking for:
teleconnections.

"It has been a surprise," says Hampton University professor of
atmospheric and planetary science James Russell, Principal Investigator
of the AIM mission. "Years ago when we were planning the AIM mission,
our attention was focused on a narrow layer of the atmosphere where NLCs
form.  Now we are finding out this layer manifests evidence of
long-distance connections in the atmosphere far from the NLCs
themselves."

One of these teleconnections links the Arctic stratosphere with the Antarctic mesosphere.

"Stratospheric winds over the Arctic control circulation in the
mesosphere," explains Randall. "When northern stratospheric winds slow
down, a ripple effect around the globe causes the southern mesosphere to
become warmer and drier, leading to fewer NLCs. When northern winds
pick up again, the southern mesosphere becomes colder and wetter, and
the NLCs return."
image

The winter air temperature in Indianapolis is correlated with the frequency of noctilucent clouds over Antarctica. More
This January, a time of year when southern NLCs are usually
abundant, the AIM spacecraft observed a sudden and unexpected decline in
the clouds. Interestingly, about two weeks earlier, winds in the Arctic
stratosphere were strongly perturbed, leading to a distorted polar
vortex.

"We believe that this triggered a ripple effect that led to a
decline in noctilucent clouds half-way around the world," says Laura
Holt of the University of Colorado's Laboratory for Atmospheric and
Space Physics. "This is the same polar vortex that made headlines this
winter when parts of the USA experienced crippling cold and ice."

Holt took a careful look at meteorological data and found that,
indeed, there was a statistical link between winter weather in the USA
and the decline in noctilucent clouds over Antarctica.

"We picked Indianapolis as an example, because I have family
living there," says Randall, "but the same was true of many northern
cities: cold air temperatures on the ground were correlated with NLC
frequencies high above Antarctica two weeks later," she says.

The two week delay is, apparently, how much time it takes for the
teleconnection signal to propagate through three layers of atmosphere
(the troposphere, stratosphere and mesosphere), and from pole to pole.

It is a complicated topic, but this much is clear: "NLCs are a
valuable resource for studying long-distance connections in the
atmosphere," says Russell, "and we are just getting started."

Credits:Author: Dr. Tony Phillips |  Production editor: Dr. Tony Phillips | Credit: Science@NASA

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Lyrid meteor shower

By: Susie77, 11:45 PM GMT on April 10, 2014


By in
| Astronomy Essentials on Apr 10, 2014


Everything you need to know: Lyrid meteor shower
Lyrids and others via NASA/MSFC/D. Moser

Lyrids and others via NASA/MSFC/D. Moser







Short-lived Lyrids’ peak comes on morning of April 22.
In 2014, moon rises in middle of the night, but these meteors are
bright. Some will withstand the moonlight.



The annual Lyrid meteor shower is active each year from about
April 16 to 25. The short-lived peak of this shower usually lasts for
less than a day. In 2014, the peak date will probably fall on April 22,
with the greatest number of meteors falling during the few hours before
dawn. A last quarter moon,
rising in the middle of the night, intrudes on the Lyrid shower in
2014, but these meteors tend to be bright. Some may overcome the
moonlight. Follow the links below to learn more about the Lyrid meteor
shower: April’s shooting stars!
How many Lyrids meteors can I expect to see?
Where is the radiant point for the Lyrid meteor shower?
Lyrid meteors in history.
How to watch the Lyrid meteors.
Comet Thatcher is the source of the Lyrid meteors.
What was that date again?

A fireball meteor falling earthward, courtesy of NASA/George Varros
How many Lyrids meteors can I expect to see?
On a moonless night, you can often see up 10 to 20 meteors an hour at
the shower’s peak. Due to the phase of the moon, meteor counts could be
down in 2014.
On the other hand, meteor showers are notorious for defying the most
careful predictions. The Lyrids stand as no exception. An outburst of
Lyrid meteors is always a possibility (though no Lyrid outburst is
predicted for 2014).
For instance, American observers saw an outburst of nearly 100 Lyrid
meteors per hour in 1982. Around 100 meteors per hour were seen in
Greece in 1922 and from Japan in 1945.
Meteor-watchers are risk-takers, as a group. They’re always hoping
for that fabulous display. So you can bet that some aficionados will be
out there on April 22, set up to watch the 2014 Lyrids, despite the
moon.
The radiant point of the Lyrid meteor shower is near the bright star Vega in the constellation Lyra the Harp.
The radiant point of the Lyrid meteor shower is near the bright star Vega in the constellation Lyra the Harp.

Another
view of the brilliant star Vega, which nearly coincides with the
radiant point of April’s Lyrid meteor shower. Image via AlltheSky


Where is the radiant point for the Lyrid meteor shower?
If you trace the paths of all the Lyrid meteors backward, they seem to
radiate from the constellation Lyra the Harp, near the brilliant star
Vega. However, this is only a chance alignment, for these meteors burn
up in the atmosphere about 100 kilometers – or 60 miles – up. Vega lies
trillions of times farther away at 25 light-years.
The star Vega resides quite far north of the celestial equator, so
for that reason the Lyrid meteor shower favors the Northern Hemisphere.
At mid-northern latitudes, Vega sits low over the northeastern horizon
around 10 p.m. Afterwards, Vega soars upward during the nighttime hours
and reaches its highest point in the sky around dawn.
As a general rule, the higher that Vega climbs into the sky, the more
meteors that you’re likely to see. That’s why the greatest numbers of
meteors generally fly in the dark hours before dawn.
More about radiant point of April’s Lyrid meteor shower
Portrait of Confucius.
Portrait of Confucius.
Lyrid meteors in history. The
Lyrid meteor shower has the distinction of being among the oldest of
known meteor showers. Records of this shower go back for some 2,700
years.
The ancient Chinese are said to have observed the Lyrid meteors “falling like rain” in the year 687 BC.
That time period in ancient China, by the way, corresponds with what is called the Spring and Autumn Period
(about 771 to 476 BC), which tradition associates with the Chinese
teacher and philosopher Confucius, one of the first to espouse the
principle: “Do not do to others what you do not want done to yourself.”
I wonder if he saw the meteors …
How to watch the Lyrid meteors.
Fortunately, you don’t need any special equipment to watch a meteor
shower. Just find a dark, open sky away from artificial lights. Lie down
comfortably on a reclining lawn chair, and look upward.
Although the moonlight is likely to wash out some Lyrid meteors in
2014, a portion of these Lyrid meteors should be bright enough to
overcome the moonlit glare.
Another beautiful feature of the Lyrids to watch for … about one quarter of these swift meteors exhibit persistent trains – that is, ionized gas trails that glow for a few seconds after the meteor has passed.
Lyrids and others via NASA/MSFC/D. Moser
Lyrids and others via NASA/MSFC/D. Moser
Comet Thatcher is the source of the Lyrid meteors.
Every year, in the later part of April, our planet Earth crosses the
orbital path of Comet Thatcher (C/1861 G1), of which there are no
photographs due to its roughly a 415-year orbit around the sun. Comet
Thatcher last visited the inner solar system in 1861, before the
photographic process became widespread. This comet isn’t expected to
return until the year 2276.
Bits and pieces shed by this comet litter its orbit and bombard the
Earth’s upper atmosphere at 177,000 kilometers (110,000 miles) per hour.
The vaporizing debris streaks the nighttime with medium-fast Lyrid
meteors.
If Earth passes through an unusually thick clump of comet rubble, an elevated number of meteors could be in store.
What was that date again? So heads up in late April! The Lyrids will probably be best between midnight and dawn on April 22, 2014. The light of the last quarter moon
will interfere, but if you’re out there with friends, a lawn chair to
recline on, a sleeping bag to stay warm and thermos of something hot to
drink … you’ll have fun.
Bottom line: Remember that the Lyrids aren’t the year’s best meteor
shower. In the Northern Hemisphere, that distinction often goes to the
Perseids in August or the Geminids in December. But the Lyrids do offer
10 to 20 meteors per hour at their peak on a moonless night; in 2014,
the last quarter moon will likely temper the production before dawn on
April 22. And remember that, like all meteor showers, the Lyrids aren’t
altogether predictable. In rare instances, they can bombard the sky
with up to nearly 100 meteors per hour.


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Moon, Jupiter, Winter Circle after sunset April 5, 6 and 7

By: Susie77, 1:38 PM GMT on April 05, 2014


Moon, Jupiter, Winter Circle after sunset April 5, 6 and 7


2014-april-5-jupiter-moon-night-sky-chart


Look for the waxing crescent moon
as soon as darkness falls on April 5, 2014. The nearby super-brilliant
“star” is Jupiter, the fifth planet outward from the sun. The moon will
be even closer to Jupiter tomorrow, as darkness falls on April 6.
For a challenge, you might want to use the moon and Jupiter to
star-hop to the great big loop of stars known as Winter Circle. This
Winter Circle is an asterism – a star pattern that is not a
constellation. In fact, this brilliant star formation dwarfs the
constellation Orion, with Orion’s bright star Rigel marking the southwest part of the Winter Circle.


The Winter Circle lassos the waxing crescent moon and the planet Jupiter on April 5, 2014.

The Winter Circle lassos the waxing crescent moon and the planet Jupiter on April 5, 2014.

You can see the Winter Circle from southerly latitudes in the
Southern Hemisphere, too. Keep in mind, however, that from this part of
the world, the Winter Circle appears “upside-down,” with the star Sirius at top and the star Capella at bottom. Nonetheless, the moon, Jupiter and the constellation Orion  serve as your guides to the Winter Circle from either the Northern or
Southern Hemisphere.

If you’re familiar with the three moderately-bright stars of Orion’s
Belt, use this compact line of stars to find two Winter Circle stars:
Sirius and Aldebaran. Orion’ Belt points in one direction to Sirius, the
brightest star in the nighttime sky; and in the opposite direction, to Aldebaran, the brightest star in the constellation Taurus the Bull.

The two stars in the vicinity of Jupiter are Castor and Pollux, the two brightest stars in the constellation Gemini the Twins. The star Procyon is found between Sirius and the Gemini stars, whereas Capella reigns as the northernmost star of the Winter Circle.

You can count on Jupiter to be your guide to the Winter Circle throughout April and May of 2014.

Bottom line: Northern Hemisphere spring is here, but the Winter Circle
star are still here, for awhile. Soon, this star formation will start
to sink into the sunset glare. On April 5, 6 and 7, the moon is also in
this part of the sky. Jupiter is the bright object near the moon on
these nights.

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About Susie77

Sometimes I complain about the earthly weather, but mostly I like to post about astronomy and space events. Hope you enjoy the articles.

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