Tuesday, November 18, 2014

Whittling Away At SN1987A

Whittling Away At SN1987A:



Left Panel: SNR1987A as seen by the Hubble Space Telescope in 2010.Middle Panel: SNR1987A as seen by the Australia Telescope Compact Array (ATCA) in New South Wales and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. Right Panel: A computer generated visualisation of the remnant showing the possible location of a Pulsar. Credit: ATCA & ALMA Observations & data - G. Zanardo et al. / HST Image: NASA, ESA, K. France (University of Colorado, Boulder), P. Challis and R. Kirshner (Harvard-Smithsonian Center for Astrophysics)


Left Panel: SNR1987A as seen by the Hubble Space Telescope in 2010.Middle Panel: SNR1987A as seen by the Australia Telescope Compact Array (ATCA) in New South Wales and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. Right Panel: A computer generated visualization of the remnant showing the possible location of a Pulsar. Credit: ATCA & ALMA Observations & data – G. Zanardo et al. / HST Image: NASA, ESA, K. France (University of Colorado, Boulder), P. Challis and R. Kirshner (Harvard-Smithsonian Center for Astrophysics)
A team of Australian astronomers has been busy utilizing some of the world’s leading radio telescopes located in both Australia and Chile to carve away at the layered remains of a relatively new supernova. Designated as SN1987A, the 28 year-old stellar cataclysm came to Southern Hemisphere observer’s attention when it sprang into action at the edge of the Large Magellanic Cloud some two and a half decades ago. Since then, it has provided researchers around the world with a ongoing source of information about one of the Universe’s “most extreme events”.

Representing the University of Western Australia node of the International Centre for Radio Astronomy Research, PhD Candidate Giovanna Zanardo led the team focusing on the supernova with the Australia Telescope Compact Array (ATCA) in New South Wales. Their observations took in the wavelengths spanning the radio to the far infrared.

“By combining observations from the two telescopes we’ve been able to distinguish radiation being emitted by the supernova’s expanding shock wave from the radiation caused by dust forming in the inner regions of the remnant,” said Giovanna Zanardo of the International Centre for Radio Astronomy Research (ICRAR) in Perth, Western Australia.

“This is important because it means we’re able to separate out the different types of emission we’re seeing and look for signs of a new object which may have formed when the star’s core collapsed. It’s like doing a forensic investigation into the death of a star.”

“Our observations with the ATCA and ALMA radio telescopes have shown signs of something never seen before, located at the centre or the remnant. It could be a pulsar wind nebula, driven by the spinning neutron star, or pulsar, which astronomers have been searching for since 1987. It’s amazing that only now, with large telescopes like ALMA and the upgraded ATCA, we can peek through the bulk of debris ejected when the star exploded and see what’s hiding underneath.”

A video compilation showing Supernova Remnant 1987A as seen by the Hubble Space Telescope in 2010, and by radio telescopes located in Australia and Chile in 2012. The piece ends with a computer generated visualization of the remnant showing the possible location of a Pulsar. Credit: Dr Toby Potter, ICRAR-UWA, Dr Rick Newton, ICRAR-UWA

But, there is more. Not long ago, researchers published another paper which appeared in the Astrophysical Journal. Here they made an effort to solve another unanswered riddle about SN1987A. Since 1992 the supernova appears to be “brighter” on one side than it does the other! Dr. Toby Potter, another researcher from ICRAR’s UWA node took on this curiosity by creating a three-dimensional simulation of the expanding supernova shockwave.

“By introducing asymmetry into the explosion and adjusting the gas properties of the surrounding environment, we were able to reproduce a number of observed features from the real supernova such as the persistent one-sidedness in the radio images”, said Dr. Toby Potter.

So what’s going on? By creating a model which spans over a length of time, researchers were able to emulate an expanding shock front along the eastern edge of the supernova remnant. This region moves away more quickly than its counterpart and generates more radio emissions. When it encounters the equatorial ring – as observed by the Hubble Space Telescope – the effect becomes even more pronounced.

A visualization showing how Supernova1987A evolves between May of 1989 and July of 2014. Credit: Dr Toby Potter, ICRAR-UWA, Dr Rick Newton, ICRAR-UWA

“Our simulation predicts that over time the faster shock will move beyond the ring first. When this happens, the lop-sidedness of radio asymmetry is expected to be reduced and may even swap sides.”

“The fact that the model matches the observations so well means that we now have a good handle on the physics of the expanding remnant and are beginning to understand the composition of the environment surrounding the supernova – which is a big piece of the puzzle solved in terms of how the remnant of SN1987A formed.”

Original Story Source: Astronomers dissect the aftermath of a Supernova – International Centre for Radio Astronomy Research News Release.



About 

Tammy is a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She’s received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status.
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Chaotic Wombs May Birth Wrong-way Planets

Chaotic Wombs May Birth Wrong-way Planets:



Turbulent somethings lead to something. Image Credit: Vob


Turbulent conditions lead to retrograde exoplanets. Image Credit: Vorobyov
We’ve heard it time and time again. When it comes to new exoplanet findings, our conventional wisdom never holds. So the surprise that a batch of extrasolar planets are moving retrograde, orbiting in directions opposite to the way their stars are spinning, shouldn’t come as a surprise.

Then again, maybe it should. These discoveries turned the long-standing view of how planets form on its head. Now Eduard Vorobyov at the University of Vienna and colleagues argue that chaotic conditions in the planetary system’s gaseous wombs may be to blame.

Theorists have long assumed that stars and their planetary companions assemble from spinning disks of gas and dust. This causes the star to spin in one direction, while its planetary companions follow suit. “In some fundamental sense, the cloud carries a ‘genetic code’ that obligates the formation of corotating stars and planets,” Vorobyov told Universe Today.

So how do these wrong-way exoplanets get out of whack? Some theorists have postulated that the gravitational tugs from neighbors might change their direction of rotation. But this is pretty difficult for massive planets.

So Vorobyov and his colleagues took a second look at the initial clouds in which stars and their corotating planets form. Initially, astronomers thought that clouds evolve in relative isolation. Recent simulations, however, suggest that “clouds form within a turbulent environment and move like bees in a hive from one place to another,” said Vorobyov.

So a moving cloud might end up in an environment that’s quite different from the one it had at birth. It could even find itself surrounded by gas that’s swirling opposite to its spin.

Vorobyov and colleagues ran simulations that place clouds into environments with various characteristics. Sure enough when a gas cloud is surrounded by gas that’s swirling in the opposite direction, the inner disk continues to rotate in the same direction of the star, but the outer disk flips and starts to rotate in the opposite direction.

Over time, grains glom together in both disks until they ultimately form planets. Any inner planets will rotate with the star and any outer planets will rotate opposite the star.



ALMA image of the protoplanetary disc around HL Tauri


ALMA image of the protoplanetary disc around HL Tauri. Image Credit: ALMA / ESO / NOAJ / NRAO / NSF
But there are a few interesting byproducts. The first is that there’s a gap between the two counter-rotating disks. So whenever we see gaps in protoplanetary disks (like the one ALMA spotted a few weeks ago), these gaps might not be the result of a forming planet, but instead a null space between two counter-rotating disks.

The second is that the outer disk produces shock waves, which can trigger early planet formation. “The idea that planets would naturally form in the first very short (100,000 to 400,000 years) lifetime of the protostar would be profound, even if some of the planets were later destroyed,” expert Joel Green from the University of Texas told Universe Today.

This stands in contrast to the idea that planets collect their mass from collisions. It’s a process that astronomers think takes millions of years. But Green isn’t completely convinced by the simulations just yet as there seems to be no physical reason for the outer disks to end up counter rotating.

It all really comes down to the question of nature vs. nurture. “In some philosophical sense, the nurture (external environment) may completely change the nature of planet-forming disks,” said Vorobyov.

The results will be published in Astronomy & Astrophysics and are available online.



About 

Shannon Hall is a freelance science journalist. She holds two B.A.'s from Whitman College in physics-astronomy and philosophy, and an M.S. in astronomy from the University of Wyoming. Currently, she is working toward a second M.S. from NYU's Science, Health and Environmental Reporting program. You can follow her on Twitter @ShannonWHall.
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NASA’s RapidScat Ocean Wind Watcher Starts Earth Science Operations at Space Station

NASA’s RapidScat Ocean Wind Watcher Starts Earth Science Operations at Space Station:



ISS-RapidScat data on a North Atlantic extratropical cyclone, as seen by the National Centers for Environmental Prediction Advanced Weather Interactive Processing System used by weather forecasters at the National Oceanic and Atmospheric Administration's Ocean Prediction Center. Image Credit: NASA/JPL-Caltech/NOAA


ISS-RapidScat data on a North Atlantic extratropical cyclone, as seen by the National Centers for Environmental Prediction Advanced Weather Interactive Processing System used by weather forecasters at the National Oceanic and Atmospheric Administration’s Ocean Prediction Center. Image Credit: NASA/JPL-Caltech/NOAA
Barely two months after being launched to the International Space Station (ISS), NASA’s first science payload aimed at conducting Earth science from the station’s exterior has started its ocean wind monitoring operations two months ahead of schedule.

Data from the ISS Rapid Scatterometer, or ISS-RapidScat, payload is now available to the world’s weather and marine forecasting agencies following the successful completion of check out and calibration activities by the mission team.

Indeed it was already producing high quality, usable data following its power-on and activation at the station in late September and has monitored recent tropical cyclones in the Atlantic and Pacific Oceans prior to the end of the current hurricane season.

RapidScat is designed to monitor ocean winds for climate research, weather predictions, and hurricane monitoring for a minimum mission duration of two years.

“RapidScat is a short mission by NASA standards,” said RapidScat Project Scientist Ernesto Rodriguez of JPL.

“Its data will be ready to help support U.S. weather forecasting needs during the tail end of the 2014 hurricane season. The dissemination of these data to the international operational weather and marine forecasting communities ensures that RapidScat’s benefits will be felt throughout the world.”



ISS-RapidScat instrument, shown in this artist's rendering, was launched to the International Space Station aboard the SpaceX CRS-4 mission on Sept. 21, 2014 and attached at ESA’s Columbus module. It will measure ocean surface wind speed and direction and help improve weather forecasts, including hurricane monitoring. Credit: NASA/JPL-Caltech/Johnson Space Center.


ISS-RapidScat instrument, shown in this artist’s rendering, was launched to the International Space Station aboard the SpaceX CRS-4 mission on Sept. 21, 2014, and attached at ESA’s Columbus module. It will measure ocean surface wind speed and direction and help improve weather forecasts, including hurricane monitoring. Credit: NASA/JPL-Caltech/Johnson Space Center.
The 1280 pound (580kilogram) experimental instrument was developed by NASA’s Jet Propulsion Laboratory. It’s a cost-effective replacement to NASA’s former QuikScat satellite.

The $26 million remote sensing instrument uses radar pulses reflected from the ocean’s surface at different angles to calculate the speed and direction of winds over the ocean for the improvement of weather and marine forecasting and hurricane monitoring.

The RapidScat, payload was hauled up to the station as part of the science cargo launched aboard the commercial SpaceX Dragon CRS-4 cargo resupply mission that thundered to space on the company’s Falcon 9 rocket from Space Launch Complex-40 at Cape Canaveral Air Force Station in Florida on Sept. 21.

ISS-RapidScat is NASA’s first research payload aimed at conducting near global Earth science from the station’s exterior and will be augmented with others in coming years.



ISS-RapidScat viewed the winds within post-tropical cyclone Nuri as it moved parallel to Japan on Nov. 6, 2014 05:30 UTC. Image Credit: NASA/JPL-Caltech


ISS-RapidScat viewed the winds within post-tropical cyclone Nuri as it moved parallel to Japan on Nov. 6, 2014, 05:30 UTC. Image Credit: NASA/JPL-Caltech
It was robotically assembled and attached to the exterior of the station’s Columbus module using the station’s robotic arm and DEXTRE manipulator over a two day period on Sept 29 and 30.

Ground controllers at Johnson Space Center intricately maneuvered DEXTRE to pluck RapidScat and its nadir adapter from the unpressurized trunk section of the Dragon cargo ship and attached it to a vacant external mounting platform on the Columbus module holding mechanical and electrical connections.

The nadir adapter orients the instrument to point its antennae at Earth.

The couch sized instrument and adapter together measure about 49 x 46 x 83 inches (124 x 117 x 211 centimeters).

“The initial quality of the RapidScat wind data and the timely availability of products so soon after launch are remarkable,” said Paul Chang, ocean vector winds science team lead at NOAA’s National Environmental Satellite, Data and Information Service (NESDIS)/Center for Satellite Applications and Research (STAR), Silver Spring, Maryland.

“NOAA is looking forward to using RapidScat data to help support marine wind and wave forecasting and warning, and to exploring the unique sampling of the ocean wind fields provided by the space station’s orbit.”



A SpaceX Falcon 9 rocket carrying a Dragon cargo capsule packed with science experiments and station supplies blasts off from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida, at 1:52 a.m. EDT on Sept. 21, 2014 bound for the ISS. Credit: Ken Kremer/kenkremer.com


A SpaceX Falcon 9 rocket carrying a Dragon cargo capsule packed with science experiments and station supplies blasts off from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida, at 1:52 a.m. EDT on Sept. 21, 2014, bound for the ISS. Credit: Ken Kremer/kenkremer.com
This has been a banner year for NASA’s Earth science missions. At least five missions will be launched to space within a 12 month period, the most new Earth-observing mission launches in one year in more than a decade.

ISS-RapidScat is the third of five NASA Earth science missions scheduled to launch over a year.

NASA has already launched the of the Global Precipitation Measurement (GPM) Core Observatory, a joint mission with the Japan Aerospace Exploration Agency, in February and the Orbiting Carbon Observatory-2 (OCO-2) carbon observatory in July 2014.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer



About 

Dr. Ken Kremer is a speaker, scientist, freelance science journalist (Princeton, NJ) and photographer whose articles, space exploration images and Mars mosaics have appeared in magazines, books, websites and calanders including Astronomy Picture of the Day, NBC, BBC, SPACE.com, Spaceflight Now and the covers of Aviation Week & Space Technology, Spaceflight and the Explorers Club magazines. Ken has presented at numerous educational institutions, civic & religious organizations, museums and astronomy clubs. Ken has reported first hand from the Kennedy Space Center, Cape Canaveral and NASA Wallops on over 40 launches including 8 shuttle launches. He lectures on both Human and Robotic spaceflight - www.kenkremer.com. Follow Ken on Facebook and Twitter
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Monday, November 17, 2014

Black Hole Powered Jets Plow Into Galaxy

Black Hole Powered Jets Plow Into Galaxy:



4C+29.30


This composite image
of a galaxy illustrates how the intense gravity of a supermassive
black hole can be tapped to generate immense power. The image
contains X-ray data from NASA's Chandra X-ray Observatory (blue),
optical light obtained with the Hubble Space Telescope (gold) and
radio waves from the NSF's Very Large Array (pink).

This multi-wavelength view shows 4C+29.30, a galaxy
located some 850 million light years from Earth. The radio emission
comes from two jets of particles that are speeding at millions of
miles per hour away from a supermassive black hole at the center of
the galaxy. The estimated mass of the black hole is about 100
million times the mass of our Sun. The ends of the jets show larger
areas of radio emission located outside the galaxy.

The X-ray data show a different aspect of this galaxy,
tracing the location of hot gas. The bright X-rays in the center of
the image mark a pool of million-degree gas around the black hole.
Some of this material may eventually be consumed by the black hole,
and the magnetized, whirlpool of gas near the black hole could in
turn, trigger more output to the radio jet.

Most
of the low-energy X-rays from the vicinity of the black hole are
absorbed by dust and gas, probably in the shape of a giant doughnut
around the black hole. This doughnut, or torus blocks all the
optical light produced near the black hole, so astronomers refer to
this type of source as a hidden or buried black hole. The optical
light seen in the image is from the stars in the galaxy.

The bright spots in X-ray and radio emission on the outer
edges of the galaxy, near the ends of the jets, are caused by
extremely high energy electrons following curved paths around
magnetic field lines. They show where a jet generated by the black
hole has plowed into clumps of material in the galaxy (mouse over
the image for the location of these bright spots). Much of the
energy of the jet goes into heating the gas in these clumps, and
some of it goes into dragging cool gas along the direction of the
jet. Both the heating and the dragging can limit the fuel supply
for the supermassive black hole, leading to temporary starvation
and stopping its growth. This feedback process is thought to cause
the observed correlation between the mass of the supermassive black
hole and the combined mass of the stars in the central region or
bulge of a galaxy.

More at http://chandra.harvard.edu/photo/2013/4c2930/

-Megan Watzke, CXC



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NASA X-ray Telescopes Find Black Hole May Be a Neutrino Factory

NASA X-ray Telescopes Find Black Hole May Be a Neutrino Factory:



Sagittarius A*


The supermassive black hole at the center of the Milky Way, seen in this image from NASA's Chandra X-ray Observatory, may be producing mysterious particles called neutrinos, as described in our latest press release. Neutrinos are tiny particles that have virtually no mass and carry no electric charge. Unlike light or charged particles, neutrinos can emerge from deep within their sources and travel across the Universe without being absorbed by intervening matter or, in the case of charged particles, deflected by magnetic fields.

While the Sun produces neutrinos that constantly bombard the Earth, there are also other neutrinos with much higher energies that are only rarely detected. Scientists have proposed that these higher-energy neutrinos are created in the most powerful events in the Universe like galaxy mergers, material falling onto supermassive black holes, and the winds around dense rotating stars called pulsars.

Using three NASA X-ray telescopes, Chandra, Swift, and NuSTAR, scientists have found evidence for one such cosmic source for high-energy neutrinos: the 4-million-solar-mass black hole at the center of our Galaxy called Sagittarius A* (Sgr A*, for short). After comparing the arrival of high-energy neutrinos at the underground facility in Antarctica, called IceCube, with outbursts from Sgr A*, a team of researchers found a correlation. In particular, a high-energy neutrino was detected by IceCube less than three hours after astronomers witnessed the largest flare ever from Sgr A* using Chandra. Several flares from neutrino detections at IceCube also appeared within a few days of flares from the supermassive black hole that were observed with Swift and NuSTAR.

This Chandra image shows the region around Sgr A* in low, medium, and high-energy X-rays that have been colored red, green, and blue respectively. Sgr A* is located within the white area in the center of the image. The blue and orange plumes around that area may be the remains of outbursts from Sgr A* that occurred millions of years ago. The flares that are possibly associated with the IceCube neutrinos involve just the Sgr A* X-ray source.

More information at http://chandra.harvard.edu/photo/2014/sgra/index.html

-Megan Watzke, CXC

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NASA Holds Telecon on Rocket Experiment Results

NASA Holds Telecon on Rocket Experiment Results:

Spitzer Spies Spectacular Sombrero
The Sombrero galaxy as seen by NASA's Spitzer and Hubble space telescopes in a combined visible- and infrared-light view. Image credit: NASA/JPL-Caltech/University of Arizona

› Full image and caption
NASA will host a news teleconference at 11 a.m. PST (2 p.m. EST) Thursday, Nov. 6, to announce discoveries from a sub-orbital rocket experiment that are redefining what we think of as galaxies.

The results are embargoed by the journal Science until 11 a.m. PST (2 p.m. EST) Nov. 6.

The briefing participants are:

-- Michael Garcia, program scientist, NASA Headquarters, Washington

-- James Bock, astronomer, NASA's Jet Propulsion Laboratory and California Institute of Technology, Pasadena, California

-- Michael Zemcov, astronomer, Caltech and JPL

-- Karoline Gilbert, assistant astronomer, Space Telescope Science Institute, Baltimore, Maryland

Audio of the teleconference will be streamed live at:

http://www.nasa.gov/newsaudio

Visuals will be posted at the start of the event at:

http://www.nasa.gov/mission_pages/sounding-rockets/

Audio and supporting visuals will be streamed live at:

http://www.ustream.tv/NASAJPL2

For more information, visit:

http://www.nasa.gov

Media Contact

Whitney Clavin

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-4673

whitney.clavin@jpl.nasa.gov

Felicia Chou
NASA Headquarters, Washington
202-358-0257
felicia.chou@nasa.gov

2014-379
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NASA Rolls Out Enhanced, Mobile-Friendly Climate Site

NASA Rolls Out Enhanced, Mobile-Friendly Climate Site:

NASA's Global Climate Change website tracks key indicators of climate change
NASA's Global Climate Change website tracks key indicators of climate change, include the retreat of glaciers and the shrinking of ice sheets around the world. Image credit: Shutterstock

› Larger image
NASA has relaunched its Webby Award-winning website, Global Climate Change, with enhanced interactive features that play on any mobile device, state-of-the-art visuals, and new sections on climate change solutions and the people behind the science.

First launched in 2008, the Global Climate Change website provides easy-to-understand information about the causes and effects of climate change and the ways NASA studies them, along with the latest climate news from the agency, graphics and visualizations. The URL is:

http://climate.nasa.gov

Highlights of the redesign include:

-- An improved Vital Signs dashboard, providing interactive charts with continuously updated data on atmospheric carbon dioxide, sea level rise, Arctic ice extent, global temperature and other key indicators of climate change

-- Visualizations of change over time from NASA's Scientific Visualization Studio

-- A section that focuses on science and technology advances that are providing essential data for adapting to and mitigating the effects of climate change

-- Making a Difference, a section that highlights NASA's climate researchers and the work they do

The updated site retains popular features of the earlier version, including the Images of Change gallery, the Climate Time Machine and the Eyes on the Earth data visualization tool.

The website is optimized for most mobile devices, including smartphones and tablets.

"NASA is a world leader in Earth system science and climate research, and it's important that we make the content of our work accessible to the general public," said Peg Luce, deputy director of NASA's Earth Science Division. "The continuing popularity and recognition of this site underscores the need for credible resources with timely climate change information."

For more information on NASA's Earth Science Program, visit:

http://science.nasa.gov/earth-science/ and

http://www.nasa.gov/earthrightnow/

Media Contact

Alan Buis

818-354-0474

Jet Propulsion Laboratory, Pasadena, California

Alan.Buis@jpl.nasa.gov

Written by Carol Rasmussen
NASA Earth Science News Team

2014-384
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Jupiter's Red Spot is Likely a Sunburn, Not a Blush

Jupiter's Red Spot is Likely a Sunburn, Not a Blush:

Research suggests effects of sunlight produce the color of Jupiter's Great Red Spot.
Research suggests effects of sunlight produce the color of Jupiter's Great Red Spot. The feature's clouds are much higher than those elsewhere on the planet, and its vortex nature confines the reddish particles once they form. Image credit: NASA/JPL-Caltech/ Space Science Institute

› Larger image
The ruddy color of Jupiter's Great Red Spot is likely a product of simple chemicals being broken apart by sunlight in the planet's upper atmosphere, according to a new analysis of data from NASA's Cassini mission. The results contradict the other leading theory for the origin of the spot's striking color -- that the reddish chemicals come from beneath Jupiter's clouds.

The results are being presented this week by Kevin Baines, a Cassini team scientist based at NASA's Jet Propulsion Laboratory, Pasadena, California, at the American Astronomical Society's Division for Planetary Science Meeting in Tucson, Arizona.

Baines and JPL colleagues Bob Carlson and Tom Momary arrived at their conclusions using a combination of data from Cassini's December 2000 Jupiter flyby and laboratory experiments.

In the lab, the researchers blasted ammonia and acetylene gases -- chemicals known to exist on Jupiter -- with ultraviolet light, to simulate the sun's effects on these materials at the extreme heights of clouds in the Great Red Spot. This produced a reddish material, which the team compared to the Great Red Spot as observed by Cassini's Visible and Infrared Mapping Spectrometer (VIMS). They found that the light-scattering properties of their red concoction nicely matched a model of the Great Red Spot in which the red-colored material is confined to the uppermost reaches of the giant cyclone-like feature.

"Our models suggest most of the Great Red Spot is actually pretty bland in color, beneath the upper cloud layer of reddish material," said Baines. "Under the reddish 'sunburn' the clouds are probably whitish or grayish." A coloring agent confined to the top of the clouds would be inconsistent with the competing theory, which posits that the spot's red color is due to upwelling chemicals formed deep beneath the visible cloud layers, he said. If red material were being transported from below, it should be present at other altitudes as well, which would make the red spot redder still.

Jupiter is composed almost entirely of hydrogen and helium, with just a sprinkling of other elements. Scientists are interested in understanding what combinations of elements are responsible for the hues seen in Jupiter's clouds, as this would provide insights into the giant planet's make-up.

Baines and colleagues initially set out to determine if the Great Red Spot's color might derive from sun-induced breakdown of a more complex molecule, ammonium hydrosulfide, which makes up one of Jupiter's main cloud layers. They quickly found that instead of a red color, the products their experiment produced were a brilliant shade of green. This surprising negative result prompted the researchers to try simple combinations of ammonia with hydrocarbons that are common at Jupiter's high altitudes. Breaking down ammonia and acetylene with ultraviolet light turned out to best fit the data collected by Cassini.

The Great Red Spot is a long-lived feature in Jupiter's atmosphere that is as wide as two earths. Jupiter possesses three main cloud layers, which occupy specific altitudes in its skies; from highest to lowest they are: ammonia, ammonium hydrosulfide and water clouds.

As for why the intense red color is seen only in the Great Red Spot and a few much smaller spots on the planet, the researchers think altitude plays a key role. "The Great Red Spot is extremely tall," Baines said. "It reaches much higher altitudes than clouds elsewhere on Jupiter."

The team thinks the spot's great heights both enable and enhance the reddening. Its winds transport ammonia ice particles higher into the atmosphere than usual, where they are exposed to much more of the sun's ultraviolet light. In addition, the vortex nature of the spot confines particles, preventing them from escaping. This causes the redness of the spot's cloud tops to increase beyond what might otherwise be expected.

Other areas of Jupiter display a mixed palette of oranges, browns and even shades of red. Baines says these are places where high, bright clouds are known to be much thinner, allowing views to depths in the atmosphere where more colorful substances exist.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington. The VIMS team is based at the University of Arizona in Tucson.

More information about Cassini is available at the following sites:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

Media Contact

Preston Dyches

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-5011

preston.dyches@jpl.nasa.gov

2014-391
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Rosetta's Comet Lander Landed Three Times

Rosetta's Comet Lander Landed Three Times:

Image of the first touchdown site for the Rosetta spacecraft's Philae lander on comet 67P/Churyumov-Gerasimenko
This image of comet 67P/Churyumov-Gerasimenko marks the first touchdown point of the Philae lander of the European Space Agency's Rosetta mission. The image was taken by the Onboard Scientific Imaging System (OSIRIS) on the Rosetta orbiter from a distance of about 19 miles (30 kilometers) on Sept. 14, 2104, nearly two months before Philae's Nov. 12 landing.

› Full image and caption
On Wednesday, Nov. 12, the European Space Agency's Rosetta mission successfully landed on the surface of comet 67P/Churyumov-Gerasimenko. Descending at a speed of about 2 mph (3.2 kilometers per hour) the lander, called "Philae," first touched down and its signal was received at 8:03 a.m. PST (11:03 a.m. EST).

Partially due to anchoring harpoons not firing, and the comet's low gravity (a hundred-thousand times less than that of Earth), Philae bounced off the surface and flew up to about six-tenths of a mile (1 kilometer) both above the comet's surface as well as downrange. At 9:53 a.m. PST (12:53 p.m. EST), almost two hours after first contact, Philae again touched down. A second, more modest bounce resulted, again sending it airborne. Philae's third contact with the comet's nucleus was the charm. At 10 a.m. PST (1 p.m. EST), the Rosetta mission's Philae lander became the first spacecraft to soft-land on a comet.

Rosetta mission controllers believe Philae alighted in a hole, or crevice, about six feet (two meters) in diameter and six feet (two meters) deep and that it is lying on its side. While the lander remains unanchored to the surface, it remains stable. and eight of its 10 instruments have already begun sending back data. The science team is working on its next moves.

"Philae is on the surface and doing a marvelous job, working very well, and we can say we have a very happy lander," said Paolo Ferri, ESA's head of mission operations at the European Space Operations Center, Darmstadt, Germany.

Teams are still working to confirm the location and the overall power and thermal situation on board. The lander did receive power from some of its solar panels. It appears that some parts of the lander were in shadow during the time that last night's surface telemetry data were being transmitted.

Launched in March 2004, Rosetta was reactivated in January 2014 after a record 957 days in hibernation. The mission consists of an orbiter and lander. Its objectives since arriving at comet 67P/Churyumov-Gerasimenko this summer have been to study the celestial object up close in unprecedented detail, and prepare for yesterday's landing. The orbiter will continue tracking the comet's changes as it sweeps past the sun.

The scientific imaging system OSIRIS -- for Onboard Scientific Imaging System -- was built by a consortium led by the Max Planck Institute for Solar System Research (Germany) in collaboration with CISAS, University of Padua (Italy), the Laboratoire d'Astrophysique de Marseille (France), the Instituto de Astrofísica de Andalucia, CSIC (Spain), the Scientific Support Office of the European Space Agency (The Netherlands), the Instituto Nacional de Técnica Aeroespacial (Spain), the Universidad Politéchnica de Madrid (Spain), the Department of Physics and Astronomy of Uppsala University (Sweden), and the Institute of Computer and Network Engineering of the TU Braunschweig (Germany). OSIRIS was financially supported by the national funding agencies of Germany (DLR), France (CNES), Italy (ASI), Spain (MEC), and Sweden (SNSB) and the ESA Technical Directorate. Rosetta is a European Space Agency mission with contributions from its member states and NASA.

Rosetta's Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; National Center of Space Studies of France (CNES), Paris; and the Italian Space Agency, Rome. NASA's Jet Propulsion Laboratory in Pasadena, California, a division of the California Institute of Technology, manages the U.S. participation in the Rosetta mission for NASA's Science Mission Directorate in Washington.

For more information on the U.S. instruments aboard Rosetta, visit:
http://rosetta.jpl.nasa.gov

More information about Rosetta is available at:
http://www.esa.int/rosetta

Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

Dwayne Brown
202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

Markus Bauer
011-31-71-565-6799
European Space Agency, Noordwijk, Netherlands
markus.bauer@esa.int

2014-396
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New Map Shows Frequency of Small Asteroid Impacts, Provides Clues on Larger Asteroid Population

New Map Shows Frequency of Small Asteroid Impacts, Provides Clues on Larger Asteroid Population:

This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth's atmosphere
This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth's atmosphere to create very bright meteors, technically called "bolides" and commonly referred to as "fireballs".  Sizes of red dots (daytime impacts) and blue dots (nighttime impacts) are proportional to the optical radiated energy of impacts measured in billions of Joules (GJ) of energy, and show the location of impacts from objects about 1 meter (3 feet) to almost 20 meters (60 feet) in size. Image Credit: Planetary Science

› Larger image
A map released today by NASA's Near Earth Object (NEO) Program reveals that small asteroids frequently enter and disintegrate in the Earth's atmosphere with random distribution around the globe. Released to the scientific community, the map visualizes data gathered by U.S. government sensors from 1994 to 2013. The data indicate that Earth's atmosphere was impacted by small asteroids, resulting in a bolide (or fireball), on 556 separate occasions in a 20-year period. Almost all asteroids of this size disintegrate in the atmosphere and are usually harmless. The notable exception was the Chelyabinsk event which was the largest asteroid to hit Earth in this period. The new data could help scientists better refine estimates of the distribution of the sizes of NEOs including larger ones that could pose a danger to Earth.

Finding and characterizing hazardous asteroids to protect our home planet is a high priority for NASA. It is one of the reasons NASA has increased by a factor of 10 investments in asteroid detection, characterization and mitigation activities over the last five years. In addition, NASA has aggressively developed strategies and plans with its partners in the U.S. and abroad to detect, track and characterize NEOs. These activities also will help identify NEOs that might pose a risk of Earth impact, and further help inform developing options for planetary defense.

The public can help participate in the hunt for potentially hazardous Near Earth Objects through the Asteroid Grand Challenge, which aims to create a plan to find all asteroid threats to human populations and know what to do about them. NASA is also pursuing an Asteroid Redirect Mission (ARM) which will identify, redirect and send astronauts to explore an asteroid. Among its many exploration goals, the mission could demonstrate basic planetary defense techniques for asteroid deflection.

For more information about the map and data, go to:

http://neo.jpl.nasa.gov

For details about ARM, and the Asteroid Grand Challenge, visit:

http://www.nasa.gov/asteroidinitiative

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.

Media Contact

DC Agle

Jet Propulsion Laboratory, Pasadena, Calif.

818-393-9011

agle@jpl.nasa.gov

Dwayne Brown

NASA Headquarters, Washington

202-358-1726

dwayne.c.brown@nasa.gov

2014-397
Posted by Nelio Inacio at 5:20 PM 0 comments
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Monday, November 3, 2014

Small Spacecraft Ejected from Space Station Airlock Will Provide Same-Day, On-Demand Parcel Delivery

Small Spacecraft Ejected from Space Station Airlock Will Provide Same-Day, On-Demand Parcel Delivery:



Artist concept of the Terrestrial Return Vehicle (TRV). Credit: Intuitive Machines


Artist concept of the Terrestrial Return Vehicle (TRV). Credit: Intuitive Machines
Getting to the International Space Station is no easy task. Generally speaking, it involves loading up a space capsule with several tons of cargo and then expending millions of liters of fuel to get it into orbit. This process is time consuming and very expensive. And what if astronauts want to send some things back? Currently, their only option for return capability is provided by the same cargo capsules that are sent up to them.

Which means that the only way the ISS can send things back to Earth is for us to spend several million dollars sending a return vehicle up to them. Luckily, this is about to change, thanks to a project known as the Terrestrial Return Vehicle (TRV).


The TRV represents a collaborative effort between NASA and CASIS, the non-profit Center for the Advancement of Science in Space, which was recently endowed  with the responsibility of making sure that we make good use of the US laboratory aboard the ISS. Towards this end, they have contracted with Intuitive Machines – a Texas-based private space firm – to create a return vehicle that will enable the on-demand, rapid return of experiments from the International Space Station (ISS) National Laboratory.

“I believe with this new ‘on demand’ delivery capability for returning scientific samples to earth we will extend the viability of the ISS National Laboratory as a research platform for commercial benefit,” Steve Altemus, the president of Intuitive Machines, told Universe Today via email. “The principle investigators and scientists engaged in microgravity research in space can now begin to imagine new and different experiments and methodologies enabled by returning samples on a nearly daily basis and landing them precisely and gently on the Earth.”

The proposed TRV is a small, wingless capsule that can be loaded up with samples and ejected from the airlock in the Japanese Experiment Module (JEM), guaranteeing delivery back to Earth in under 24 hours. From the outside, the design looks a little like the Space Shuttle, or the Boeing X-37B space plane. Minus the stubby wings, of course.



Credit: NASA


The International Space Station. Credit: NASA
For the ISS crews, having these vehicles on hand will be a major boon for research, allowing for the delivery of critical or perishable samples to Earth laboratories in a timely manner. A number of these TRV’s will be shipped to the ISS – presumably as part of a normal cargo run using a SpaceX Dragon capsule.

Once there, the process for using them to make deliveries will be quite straightforward. First, astronauts will load them with the scientific samples they intend to send home. Then, they will push them out the airlock and shunt them out into space using the Station’s Japanese-made robotic arm.

The TRV will then return to Earth much like any other spacecraft, descending through the atmosphere and eventually deploying a parachute to slow it down from supersonic speeds. Another larger parachute will deploy once it’s closer to the ground and bring it safely down to a landing site in Utah.

This return trip will take six hours, and since the ISS orbits the Earth about 15 times a day, the total delivery time should always be less than 24 hours. This will be especially useful considering that a number of scientific experiments take place on the International Space Station, mainly because the zero-gravity environment is more ideal for growing cell cultures in three dimensions.



Getting a TRV from the Space Station back to Earth. Credit: Intuitive Machines (some images courtesy of NASA)


Getting a TRV from the Space Station back to Earth. Credit: Intuitive Machines (some images courtesy of NASA)
“The International Space Station, with its unique microgravity laboratories and crew, enables research over a wide range of disciplines from physics through biology,” said Dr. David Wolf, a research scientist and former astronaut. “This small payload return capability will provide controlled conditions and flexible choices for timely sample analysis. The scientific team will be able to much more efficiently adjust experimental parameters in response to results, exploit unique results, and correct problems encountered.”

In short, if astronauts are busy testing techniques for bioprinting organs or developing new types of pharmaceuticals, they would certainly prefer to send the samples produced straight back to Earth rather than being forced to wait weeks for a cargo ship to arrive.

However, beyond facilitating the research efforts of astronauts, Intuitive Machines sees the TRV as a means of enabling new and exciting research aboard the ISS National Laboratory, as well as opening the door for commercial ventures in space.

Currently, Intuitive Machines plans to provide its TRV technology to a wide range of customers – including scientific, academic, commercial, and government interests. It is their hope that the new same-day capability will enable increased utilization of the ISS as a national laboratory, and improve the commercialization opportunities of experiments for terrestrial benefit.

The first batch of TRVs is scheduled to be sent up to the ISS in 2016. At first, they will be used strictly to return scientific samples – but apparently, a version that would be capable of returning live rodents is also in the works.

Further Reading: Intuitive Machines



About 

Author, freelance writer, educator, Taekwon-Do instructor, and loving hubby, son and Island boy!
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Orbiting Solar Observatory Sees It Burn, Burn, Burn: The Ring of Fire

Orbiting Solar Observatory Sees It Burn, Burn, Burn: The Ring of Fire:



Image of the Oct. 23, 2014 eclipse acquired with the Hinode spacecraft's X-ray telescope. (NASA/JAXA/SAO)


Image of the Oct. 23, 2014, eclipse acquired with the Hinode spacecraft’s X-ray telescope. (NASA/JAXA/SAO)
Did you catch the solar eclipse on October 23? If so, you saw the Moon “take a bite” out of the Sun (to various extents, depending on your location) during what was a partial eclipse for viewers on Earth. But for the Hinode (pronunciation alert: that’s “HEE-no-day”) solar observatory satellite, in its Sun-synchronous orbit around Earth at an altitude of 600 km (373 miles), the eclipse was annular – a “ring of fire.”

The image above was captured with Hinode’s X-ray Telescope at the moment of maximum annularity. Want to watch it burn, burn, burn like Hinode did? Check out a video below:



Not to be confused with “annual,” meaning yearly, an annular eclipse occurs when the Moon passes directly in front of the Sun but at such a distance from Earth to not quite manage to fully cover the Sun’s disk. The bright ring of visible Sun around the Moon’s silhouette gives the event its name: annular is from the Latin word anulus, meaning ring.

The next annular eclipse to be visible from Earth will occur on Sept. 1, 2016.

Led by the Japan Aerospace Exploration Agency (JAXA), the Hinode mission is a collaboration between the space agencies of Japan, the United States, the United Kingdom, and Europe, and is now in its eighth year. NASA helped in the development, funding, and assembly of the spacecraft’s three science instruments. Learn more about the mission here.

Image and video credits: NASA/JAXA/SAO



About 

A graphic designer in Rhode Island, Jason writes about space exploration on his blog Lights In The Dark, Discovery News, and, of course, here on Universe Today. Ad astra!
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Completely Gorgeous Shot of the Milky Way Over Jasper National Park

Completely Gorgeous Shot of the Milky Way Over Jasper National Park:

by Nancy Atkinson on October 27, 2014


The Milky Way over Lake Annette in Jasper National Park, Alberta, a Dark Sky Preserve, on October 24, 2014. Credit and copyright: Alan Dyer/Amazing Sky Photography.


The Milky Way over Lake Annette in Jasper National Park, Alberta, a Dark Sky Preserve, on October 24, 2014. Credit and copyright: Alan Dyer/Amazing Sky Photography.
Does it get any more gorgeous than this? What an absolutely beautiful view of the night sky over Lake Annette and Whistler’s Mountain in Jasper National Park.

“I shot this at the Lake Annette Star Party, one of the Dark Sky Festival events, using the Canon 60Da and 10-22mm lens at 10mm f/4 and ISO 3200 for 1 minute, untracked,” said prolific astrophotographer Alan Dyer on Flickr. “Shot October 24, 2014, with fresh snow on Whistler across the lake and valley and on a calm night with still waters reflecting the stars.”


Absolutely spell-binding! Click on the image for larger versions on Flickr, and check out more of Alan’s stunning imagery on his website, Amazing Sky Photography.

#MilkyWayMonday

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
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Comet K1 PanSTARRS: See It Now Before it Heads South

Comet K1 PanSTARRS: See It Now Before it Heads South:



Credit:


Comet K1 PanSTARRS cruises through Hydra on October 1st. Note the twin opposing ion and dust tail. Credit: Ken Moore, used with permission.
Comet C/2012 K1 PanSTARRS, one of the most dependable comets of 2014, may put on its encore performance over the coming weeks for southern hemisphere observers.

First, the story thus far. Discovered as a +19th magnitude smudge along the borders of the constellations Ophiuchus and Hercules in mid-May 2012 courtesy of the Panoramic Survey Telescope And Rapid Response System (PanSTARRS) based atop Haleakala on the Hawaiian island of Maui, astronomers soon realized that comet C/2012 K1 PanSTARRS would be something special.

The comet broke +10th magnitude to become a visible binocular object in early 2014, and wowed northern hemisphere observers as it vaulted across the constellations of Boötes and Ursa Major this past spring.



NEOWISE


NASA’s NEOWISE mission spies K1 PanSTARRS on May 20th as it slides by the galaxy NGC 3726 (blue). Credit: NASA/JPL.
The comet is approaching the inner solar system on a retrograde, highly-inclined orbit tilted 142 degrees relative the ecliptic. This bizarre orbit also assures that the comet will actually reach opposition twice in 2014 as seen from our earthly vantage point: once on April 15th, and another opposition coming right up on November 7th.

As was the case with comet Hale-Bopp way back in 1997, had C/2012 K1 PanSTARRS arrived six months earlier or later, we would’ve been in for a truly spectacular show, as the comet reached perihelion on August 27th, 2014, only 0.05 A.U.s (4.6 million miles or 7.7 million kilometres) outside the orbit of the Earth! But such a spectacle was not to be… back in ’97, Hale-Bopp’s enormous size — featuring a nucleus estimated 40 to 60 kilometres across — made for a grand show regardless… fast forward to 2014, and the tinier nucleus of K1 PanSTARRS has been relegated to binocular status only.



Credit


The position of comet K1 PanSTARRS as it passes its second opposition of the year. Credit: NASA/JPL.
From here on out, K1 PanSTARRS is headed south “with a bullet” and into memory for most northern hemisphere observers. We spied the comet this morning low to the south near +3rd magnitude Nu Puppis in the pre-dawn sky with our trusty 15×45 binocs from Yuma, Arizona, for what will probably be our last time. This also means that the time to catch a last glimpse of K1 PanSTARRS for northern hemisphere viewers is now. This week sees the comet transiting just 20 degrees above the southern horizon at 3:00 to 4:00 AM local for observers based from latitude 30 degrees north as it crosses the constellation Puppis. The bright star Sirius nearly shares the same position as the comet in right ascension this week, and K1 PanSTARRS sits about 24 degrees south of the Dog Star.



K1 PanSTARRS jaicoa


Comet K1 PanSTARRS imaged on June 14th. Credit: Efrain Morales.
Halloween sees the comet even lower, crossing the southern meridian at only 13 degrees elevation as seen from latitude 30 degrees north. Draw a straight line from Sirius to the south celestial pole around this date to find the comet just 5 degrees to the north of Canopus.

But the show is just beginning for southern hemisphere residents. Observing from the town of Bright Australia, Robert Kaufmann recently noted in a posting on the Yahoo Groups Comet Observer’s message board that the comet currently exhibits a 4’ wide coma shining at about magnitude +7.3 with an elevation of 28 degrees above the horizon on October 25th.

And if the comet holds steady in brightness, it may break the visual threshold and become a naked eye object as seen from a dark sky site in early November.



Light curve


The projected light curve of K1 PanSTARRS with brightness observations (black dots). The vertical pink line marks the comet’s perihelion passage in late August. Credit: Seiichi Yoshida’s Weekly Information on Bright Comets.
The comet will be literally “hauling tail” across the constellation Dorado as it nears its second opposition of the year on November 7th, moving about 1.5 degrees a day – 3 times the apparent diameter of the Full Moon – on closest approach.

Currently, the comet has been observed to have an estimated magnitude holding steady at+7 and is predicted to peak at perhaps magnitude +6 early next month. And while it would’ve been great had it arrived 6 months earlier or later, the aforementioned high retrograde inclination of its orbit assured that K1 PanSTARRS was a top performer for both hemispheres in 2014.

Perihelion passage occurred two months ago, but to paraphrase a famous Monty Python skit, Comet K1 PanSTARRS is “not dead yet.”  Here are some key observing dates coming right up as the comet gains prominence in the southern hemisphere sky:

(Note that close passages of less than one degree near stars +4th magnitude or brighter only are mentioned).

Oct 31st: Passes closest to Earth, at 0.953 A.U.s distant.

Nov 1st: Crosses into the constellation Pictor.

Nov 2nd: Passes near the +3.8 magnitude star Beta Pictoris.

Nov 6th: Crosses into the constellation Dorado.

Nov 6th: Full Moon occurs, marking the beginning of an unfavorable week for comet hunting.

Nov 7th: The second opposition of the comet for 2014 occurs at 3:00 UT.

Nov 8th: Passes near the +3.3 magnitude star Alpha Doradus.

Nov 11th: Crosses into the constellation Reticulum.

Nov 13th: Crosses into the constellation Horologium.

Nov 14th: Passes 34 degrees from the South Celestial Pole.

Nov 20th: Crosses into the constellation Eridanus.

Nov 22nd: New Moon occurs, marking a week long span optimal for comet-hunting.

Nov 25th: Crosses into the constellation Phoenix.



Starry Night Education Software.


The path of K1 PanSTARRS from October 27th through December 1st. Created by the author using Starry Night Education Software.
Dec 6th: Full Moon occurs.

Dec 12th: Passes near the +2.8 magnitude star Alpha Phoenicis (Ankaa).

Dec 18th: Crosses into the constellation Sculptor.

Dec 22nd: New Moon occurs.



Looking at 2015, K1 PanSTARRS will probably fall back below +10th magnitude by late January. The comet will then head back out into the depths of the outer solar system, its multi-million year orbit only slightly altered by its inner solar system passage down into the ~700,000 year range. What will Earth be like on that far off date? Will human eyes greet the comet once again, and will anyone remember its appearance way back in the mists of time in 2014? All thoughts to ponder as we bid fair well to Comet C/2012 K1 PanSTARRS, a fine binocular comet indeed.



About 

David Dickinson is an Earth science teacher, freelance science writer, retired USAF veteran & backyard astronomer. He currently writes and ponders the universe from Tampa Bay, Florida.
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