Sometimes I complain about the earthly weather, but mostly I like to post about astronomy and space events. Hope you enjoy the articles.
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
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.
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
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.
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.
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.
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
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.
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
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."
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.
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
“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
By: Susie77, 10:47 PM GMT on November 11, 2013
Taurid meteors peak in moonlight on night of November 11-12
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.
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.
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.
By: Susie77, 2:38 PM GMT on November 09, 2013
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.