Earth Weather / Space Weather

Go ISON Go!

By: Susie77, 2:35 PM GMT on November 28, 2013

Courtesy of earthsky.org/space/big-sun-diving-comet-ison-might -be-spectacular-in-2013


Everything you need to know: Go, Comet ISON, go!
Comet ISON Nov. 25, 2013 via SECCHI

Comet ISON Nov. 25, 2013 via SECCHI









After traveling a light-year’s distance from the Oort
comet cloud , Comet ISON will encounter the sun today at around 18:44
UTC/ 1:44 p.m. EST.





comet-ison-bright-tweet
NOVEMBER 28, 2013. Today’s the day. After
traveling a light-year’s distance – over a million years – from the Oort
comet cloud surrounding our solar system, Comet ISON will encounter the
sun today. It’ll sweep only 730,000 miles (1.1 million km) above the
sun’s surface. If it survives this encounter – and things are looking
very, very good at this moment – Comet ISON may go on to become a
beautiful comet in Earth’s sky.
Want to watch its moment of truth? Your best bet for the few hours around perihelion may be NASA’s SDO page. Perihelion comes at around 18:44 UTC/ 1:44 p.m. EST on November 28. Look here to translate Universal Time to your time.
Or participate in a Google hangout with experts today. It’ll include
live feed from NASA’s SOHO sun-observing satellite and from the Kitt
Peak Observatory solar telescope. The hangout will take place at 18:00 –
20:30 UTC (1:00 – 3:30 p.m. EST).
Experts will also be answering questions live from Twitter; use the hashtags #ISON and #askNASA.
Click here for more links to real-time images of Comet ISON this week
Here’s how Comet ISON looked via SOHO yesterday.

Follow the links below for more information about Comet ISON.
When will we know if Comet ISON has disintegrated?
What was the evidence for Comet Lovejoy’s disintegration early in the week of November 25?
What might happen to ISON when closest to the sun? NASA’s Don Yeomans explains.
How has Comet ISON looked from Earth, so far?
When will be the best time to see Comet ISON from Earth?
Will Comet ISON still be visible to the eye in January, 2014?
Will Comet ISON live up to expectations?
Best photos, images, videos of Comet ISON
This
is what we’re hoping for: a very bright comet in Earth’s skies. This
is NOT Comet ISON. It’s Comet Lovejoy of 2011. Like ISON, that comet
was a sungrazer. It was one of the most beautiful comets in living
memory. Here the comet is reflected in the water of Mandurah Esturary
near Perth on December 21, 2011. Image via Colin Legg.
When will we know if Comet ISON has disintegrated? That’s a tough question because we have never witnessed such a large comet come from such a far distance, which will come so close to the sun. Karl Battams (@SungrazerComets) has a great post about this at NASA’s Comet ISON Observing Campaign website. He explained:

… we will not know if ISON will survive until it actually
does so, or gets vaporized before our very eyes! And even if we do see
it emerge from the solar atmosphere tomorrow, it will not necessarily
mean that the comet’s nucleus is intact.

ISON does not appear to have disintegrated, at least not completely,
at this time, but we still don’t know. Earlier this week, there was
evidence the comet had fragmented, but now it appears to be holding its
own. What’s more, Comet ISON has been brightening dramatically, as a
sungrazing comet should do when closest to the sun. Battams wrote:
Most of you reading this must have seen the latest SOHO images
which are updating in realtime and, as of a short time, showing us a
very healthy sungrazing comet! And indeed that’s our bottom line for
right now: Comet ISON has started to act like a sungrazing comet.
What does this mean? Well it means that ISON is now in a very
near-sun region of the solar system and is experiencing levels of solar
radiation that your average comet is never going to have to deal with.
Accordingly, its surface is boiling away furiously, releasing
tremendous amounts of ice, dust and gas and brightening up enormously.

Battams added:
The rapid brightening we are seeing now in LASCO does not
offer us any evidence at all as to whether it will survive or not. All
it does tell us is that there is still a lot of volatile material
centrally located at the comet’s head. We don’t know if there is a
coherent nucleus or not, though I would lean towards thinking there is
at least still some solid chunk in there.

In 2011, we witnessed comet C/2011 W3 (Lovejoy) pass through the
million degree solar corona and emerge the other side, seemingly in one
piece. But about two weeks later we realized that during that close
passage by the sun, its nucleus suffered a catastrophic breakup and had
actually completely dissolved within a day or so of perihelion.
Nonetheless, the comet was a spectacular sight for Southern Hemisphere observers, so this does bode well for ISON.
ison-encke-novComets
ISON (brighter) and Encke from November 19-22, 2013 as seen
encountering the solar wind. Image via Karl Battams/NRL/NASA-CIOC.

What was the evidence for Comet Lovejoy’s disintegration early in the week of November 25?
The evidence for ISON’s possible disintegration came primarily in the
form of a rapid drop in emissions, in recent days, from a certain kind
of molecule (hydrogen cyanide molecule) known to be embedded in cometary
ice.
It’s the ice of a comet like ISON that holds the comet together, and
ISON is full of fresh ice. It’s a first-time visitor from the Oort comet
cloud surrounding our solar system. If enough ice boils off the comet as it gets closer to the sun, the comet will literally fall apart.
But how much ice has ISON lost? Enough so that the comet will fall
apart? Meanwhile, dust has also been observed to be pouring from the
comet. These signs could mean that ISON’s nucleus has completely disrupted. Or not.
The good news on Tuesday, November 26 was that ISON suddenly got
brighter again. This is a sign that it still has a fairly large, fairly
intact nucleus. We’ll see, and fingers crossed!
Read the details of these recent observations from astronomer Karl Battams
View larger. | Gerald Rhemann in Namibia in SW Africa captured this photo of Comet ISON on November 21, 2013, one week before its encounter with the sun.  Visit Gerald's website Sky Vistas.View larger.
| Gerald Rhemann in Namibia in SW Africa captured this photo of Comet
ISON on November 21, 2013, one week before its encounter with the sun. Visit Gerald’s website Sky Vistas. Used with permission.
How has Comet ISON looked from Earth, so far?
November was an exciting month for Comet ISON! The comet became visible
through binoculars in early in the month and then, around November 12,
many saw that Comet ISON had had an outburst. It suddenly became much
brighter. Many began to pick it up with the eye alone in dark skies,
and many captured photos.
Also, in November, Comet ISON passed very close to the bright star
Spica, in the constellation Virgo. This bright star helped many find the
comet.
But ISON was not widely seen in November, 2013. It was still too
faint. The hope is that Comet ISON will round the sun and then brighten
dramatically in Earth skies, as it returns to view.
The best time to see Comet ISON should be early December, after its November 28 perihelion - or closest point to the sun - IF the comet survives!The
best time to see Comet ISON should be early December, after its
November 28 perihelion – or closest point to the sun – IF the comet
survives. In early December, ISON will be visible from all over Earth
in the eastern, predawn sky.
By late December, Comet ISON will have moved so far north on the sky's dome that it'll become circumpolar, visible in both the morning and evening.  This chart shows the evening view of ISON in late December and early January.By
late December, Comet ISON will have moved so far north on the sky’s
dome that it’ll become circumpolar for those at northern latitudes on
Earth, visible in both the morning and evening. This chart shows the
evening view of ISON in late December and early January. Will you need
binoculars or a telescope to see the comet then? Maybe.
When will be the best time to see Comet ISON from Earth?
Early December should be the best time to see Comet ISON, assuming it
has survived its close pass near the sun intact. The comet will be
visible in the morning sky before sunrise at its brightest.
Later in December, it’ll appear in both the morning and evening sky
(because it will have traveled so far north on the sky’s dome that it
will become circumpolar). However, don’t wait until late December, for
ISON to appear in the evening sky. As ISON’s distance from the sun
increases, it’ll grow dimmer.
Comet expert John Bortle wrote on June 13:
The crescendo of the apparition will likely occur between
December 10th and 14th, when the comet will be best seen just before
dawn after the moon sets. Although little or perhaps nothing of the head
will remain, the huge tail will loom in the northeastern sky. Almost
evenly illuminated over its length, this rapidly fading appendage could
[span] almost a quarter of the heavens as seen under good, dark
observing conditions.

December finder charts for Comet ISON here.
Comet ISON is now in the LASCO C3 field of view and is already beginning to saturate the detector. This marks a dramatic rise in brightness in the past 24 hours.  Image via ESA/NASA/Karl Battams at the Comet ISON Observing Campaign website.On
November 27, Comet ISON appeared fully in the field of view of the SOHO
mission’s LASCO C3 instrument. The comet has brightened dramtically
within the past 24 hours. It’s now beginning to ‘saturate’ (overwhelm)
the detector. That’s why Karl Battams, who labeled this image, marked
the ‘saturation spike.’ The ‘spike’ is not really part of the comet;
it’s just an artifact on the image created by so much brightness. Image
via ESA/NASA/Karl Battams at the Comet ISON Observing Campaign website.
Will Comet ISON still be visible to the eye in January, 2014?
Hopefully. Only time will tell. On January 8, 2014, the comet will lie
only 2° from Polaris — the North Star. And here’s something else that’s
fun. On January 14-15, 2014, after the comet itself has passed but when
Earth is sweeping near the comet’s orbit, it might produce a meteor
shower, or at least some beautiful night-shining or noctilucent clouds. January finder charts for Comet ISON here.
Will Comet ISON live up to expectations? Comet ISON won’t become a legendary comet of the century. Comet ISON might still break into fragments when closest to the sun, as the much-hyped Comet Elenin did around August 2011.
Or, Comet ISON might survive its encounter with the sun as Comet Lovejoy did
in late 2011. If so, when it emerges from perihelion (closest point to
sun) in early December, it might become visible to the eye. And there is
one thing we can count on. That is, if Comet ISON does become a bright comet, visible to the eyes of watching earthlings, it will be beautiful. All bright comets are.
Bottom line: Comet C/2012 S1 (ISON)’s perihelion – closest point to
the sun – is November 28, 2013. Perihelion comes at around 18:44 UTC/ 1:44 p.m. EST on November 28. Look here to translate Universal Time to your time.



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What's Next for Comet ISON?

By: Susie77, 10:48 PM GMT on November 14, 2013



Comet ISON: What's Next?


Nov. 14, 2013: 
Comet ISON is now inside the orbit of Earth as it plunges headlong
toward the sun for a fiery close encounter on Nov. 28th.  Although the
comet is not yet as bright as many forecasters predicted, the comet is
putting on a good show for observatories around the solar system.  NASA
spacecraft and amateur astronomers alike are snapping crisp pictures of
the comet's gossamer green atmosphere and filamentary double-tail.
splash
Comet ISON photographed on Nov. 10th by amateur astronomer Michael Jäger of Jauerling Austria. More
Because ISON has never passed through the inner solar system
before (it is a first-time visitor from the distant Oort cloud), experts
aren't sure what will happen next. Can the comet survive its
Thanksgiving Day brush with the sun?  Will it emerge as a bright
naked-eye object?


Lowell Observatory astronomer Matthew Knight, a member of NASA's
Comet ISON Observing Campaign, lays out some of the possibilities.


"I've grouped the possible outcomes into three scenarios,
discussed in chronological order," says Knight. "It is important to note
that no matter what happens, now that ISON has made it inside Earth's
orbit, any or all of these scenarios are scientifically exciting.  We're
going to learn a lot no matter what."
Nairas
The breakup of Comet LINEAR (D/1999 S4) as viewed by Hubble Space Telescope in 2000. More#1 Spontaneous Disintegration before Thanksgiving
The first scenario, which could happen at any time, is that ISON
spontaneously disintegrates. A small fraction (less than 1%) of comets
have disintegrated for no apparent reason.  Recent examples include
Comet LINEAR (C/1999 S4) in 2000 and Comet Elenin (C/2010 X1) in 2011.
ISON is now reaching the region of space, within ~0.8 AU of the Sun
where comets like these have disintegrated.


Comet ISON is being observed by a tremendous variety of telescopes
on Earth and beyond. If ISON does disintegrate, it would be the
best-observed case of cometary disruption in history and would likely
contribute vast new information about how comets die.

#2 Death by Sunburn around Thanksgiving Day


Assuming ISON survives the next few weeks intact, it faces an even
more daunting challenge: making it around the Sun. At closest approach
to the sun, the comet's equilibrium temperature will approach 5000
degrees Fahrenheit, hot enough to cause much of the dust and rock on
ISON's surface to vaporize.

While it may seem incredible that anything can survive this
inferno, the rate at which ISON will likely lose mass is relatively
small compared to the actual size of the comet's nucleus. ISON needs to
be 200 m wide to survive; current estimates are in the range 500 m to 2
km.  It helps that the comet is moving very fast so it will not remain
long at such extreme temperatures.

Unfortunately for ISON, it faces a double whammy from its
proximity to the Sun: even if it survives the rapid vaporization of its
exterior, it gets so close to the sun that the suns gravity might
actually pull it apart.


Destroyed comets can still be spectacular, though.  Sungrazing
Comet Lovejoy, for instance, passed within 100,000 miles of the sun's
surface in December 2011.   It disintegrated, forming a long tail of
dust that wowed observers on Earth.
Nairas
Sungrazing Comet Lovejoy (C/2011 W3) seen over Australia in Dec. 2011. Image credit: Alex Cherney, TWAN.  More#3 Survival
The final case is the most straightforward: ISON survives its
brush with the sun and emerges with enough nuclear material to continue
as an active comet.  If ISON survives in tact, it would likely lose
enough dust near the Sun to produce a nice tail. In a realistic
best-case scenario, the tail would stretch for tens of degrees and light
up the early morning sky like Comet McNaught (C/2006 P1) did in 2007.


The best of all possible worlds would be if ISON broke up just a
bit, say, into a few large pieces.  This would throw out enough extra
material to make the comet really bright from the ground, while giving
astronomers pieces of a comet to study for months to come.


"I'm clearly rooting for #3," says Knight.


"Regardless of what happens, we're going to be thrilled," he
predicts. "Astronomers are getting the chance to study a unique comet
traveling straight from 4.5 billion years of deep freeze into a near
miss with the solar furnace using the largest array of telescopes in
history."

“Hang on,” he says, “because this ride is just getting started.”


For updates and more information about Comet ISON as it approaches the sun, visit http://isoncampaign.org.
Credits:Author: Dr. Tony Phillips | Production editor: Dr. Tony Phillips | Credit: Science@NASAMore information:
Editor’s note: The text of this story is closely based on a blog
post by Matthew Knight at the CIOC web site.  It is recommended reading
for more information about the three scenarios: http://www.isoncampaign.org/mmk/what-might-happen

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Taurid Meteor Shower Peaks Tonight

By: Susie77, 10:47 PM GMT on November 11, 2013


Taurid meteors peak in moonlight on night of November 11-12







Dwayne Darnall in central Illinois captured this image of a meteor in moonlight in early 2012.


Tonight for November 11, 2013

Meteor forecasters are calling for the peak of the North Taurid
meteor shower late evening Monday, November 11 until dawn Tuesday,
November 12, 2013. This is a somewhat rambling – and sparse – shower,
and we’ve been hearing from a few people who have seen meteors already,
especially throughout this weekend. Generally speaking, the North
Taurid meteors are few and far between at mid-evening and tend to pick
up steam around midnight. Best time to watch will be the hours before
dawn. Expect as many as 5 to 10 meteors per hour. There will be a
bright waning gibbous moon in the sky this evening, which, fortunately,
will set around the time the shower is picking up.
It’s time to purchase your 2014 EarthSky moon calendar! Makes a swell gift.
This is the approximate moon phase at the peak of the November 11-12 North Taurid meteor shower.  Image via U.S. Naval Observatory.This
is the approximate moon phase at the peak of the November 11-12 North
Taurid meteor shower. Image via U.S. Naval Observatory.
So try to observe after moonset if you can! Want to know the time of moonset in your location? Try this custom sunrise-sunset calendar, and be sure to check the box for moonrise-moonset times.
Or make a night of it. There are also four planets visible in various parts of the night tonight.
Image top of post: A meteor in bright moonlight, taken in early 2012, by Dwayne Darnall in central Illinois.
The radiant point of November's North Taurid meteor shower.The radiant point of November’s North Taurid meteor shower.
The Pleiades star cluster, also known as the Seven Sisters, marks the radiant for the North Taurid meteor shower.  This cluster is part of the constellation Taurus the Bull.  Photo by Dave Dehetre on Flickr.The
Pleiades star cluster, also known as the Seven Sisters, marks the
radiant for the North Taurid meteor shower. This cluster is part of the
constellation Taurus the Bull. Photo by Dave Dehetre on Flickr.
The North Taurid meteors are named for the constellation Taurus the
Bull because the meteors appear to radiate from this part of the starry
sky. In fact, the radiant for this shower is not far from the famous
Pleiades star cluster, also known as the Seven Sisters, in Taurus.
Taurus rises over the northeast horizon around 7 to 8 p.m. at
mid-northern latitudes. At temperate latitudes in the Southern
Hemisphere, Taurus rises a few hours later.
Easily locate stars and constellations during any day and time with EarthSky’s Planisphere.
Taurus climbs upward as evening deepens into late night, and soars
highest for the night shortly after midnight. The higher that Taurus
appears in your sky, the more meteors that you’re likely to see. Because
Taurus is a northern constellation, it climbs higher in the Northern
Hemisphere sky than for our cousins in the Southern Hemisphere.
You don’t need to find the constellation Taurus to enjoy the North
Taurid meteor shower. But you do need to find a dark, open sky and to be
mindful of the setting time of the moon. Be sure to take along a
reclining lawn chair for comfort.
Bottom line: From midnight November 11, 2013 until dawn on November
12, you might see as many as 5 to 10 North Taurid meteors per hour in a
dark sky. Some might be bright! Best time to observe: After moonset on
the morning of November 12.

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Incredible Images of Super Typhoon Haiyan

By: Susie77, 2:38 PM GMT on November 09, 2013


Courtesy of  http://earthsky.org/earth/incredible-images-and-vi deo-of-super-typhoon-haiyan

By in
| | Earth | Human World on Nov 09, 2013













Incredible images and video of Super Typhoon Haiyan











Image credit: CIMSS

Image credit: CIMSS









Death toll is rising as reports trickle in from storm-damaged areas. Video and images here of Super Typhoon Haiyan.
















Super Typhoon Haiyan, called Yolanda in the Philippines, struck
the Philippines in the early morning hours of November 8, 2013 as one of
the strongest tropical cyclones to make landfall in recorded history.
At landfall, it was producing sustained winds at 195 miles per hour
(mph) with gusts as high as 225 mph. We are still receiving information
regarding damages and possible deaths. CNN reported
late in the day on November 8 that more than 100 people were killed in
the coastal Philippine city of Tacloban, but by this morning (November
9) the Red Cross was reporting
over 1,000 killed in Tacloban. For now, I will simply share these
images and video of Super Typhoon Haiyan. From a meteorological
perspective, Haiyan is no doubt the most extraordinary storm I have seen
in satellite images. We might never know exactly how powerful the storm
was, but, as I looked at the satellite imagery, I could not remember a
scarier-looking storm.
I have seen pictures of storm surge flooding towns and strong winds
blowing debris into the air. By some reports, some areas saw a storm
surge up to 50 feet (15 meters). This storm struck as a Category 5
storm, which is defined by the National Hurricane Center like this:
Catastrophic damage will occur: A high percentage of
framed homes will be destroyed, with total roof failure and wall
collapse. Fallen trees and power poles will isolate residential areas.
Power outages will last for weeks to possibly months. Most of the area
will be uninhabitable for weeks or months.

This natural color satellite image of Super Typhoon Haiyan over the Philippines. was acquired at 2:10 p.m. local time (5:10 UTC) on November 8, 2013, when winds were estimated to be 270 kph (165 mph). Image credit: NASAThis
natural color satellite image of Super Typhoon Haiyan over the
Philippines. was acquired at 2:10 p.m. local time (5:10 UTC) on November
8, 2013, when winds were estimated to be 270 kph (165 mph). Image
credit: NASA
Image credit: NOAAImage credit: NOAA
Look at Haiyan from space. Image Credit: NOAALook at Haiyan from space. Image Credit: EUMETSAT
View of Haiyan’s eye Thursday afternoon local time (05:25 UTC on November 7 or just after midnight Thursday EST) Image Credit: NOAAView
of Haiyan’s eye Thursday afternoon local time (05:25 UTC on November 7
or just after midnight Thursday EST) Image Credit: NOAA
Animation loop showing you the extremely vivid colors and cold cloud tops as Super Typhoon Haiyan continued to intensify. . Image Credit: NOAAAnimation
loop showing you the extremely vivid colors and cold cloud tops as
Super Typhoon Haiyan continued to intensify. . Image Credit: NOAA
Image credit: CIMSSImage credit: CIMSS
Here is video of the storm as it began to make landfall in the central part of the Philippines.

Bottom line: We are still getting information regarding how badly
Super Typhoon Haiyan affected parts of the Philippines. It is likely one
of the most strongest storms to ever make landfall on Earth. The
satellite imagery of this storm is simply remarkable! See images and
video in this post.


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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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