Tuesday, July 22, 2014

European Space Probe Aims for 1 Comet, Finds 2

(Image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

by Jacob Aron

Comet-chaser Rosetta has lucked out with a two-for-one deal. Pictures from the European Space Agency (ESA) probe suggest that its target comet, Churyumov-Gerasimenko, is actually two icy rocks stuck together in an arrangement known as a contact binary.

"This is the reason we organise these missions, to find surprises," says Pedro Lacerda of the Max Planck Institute for Solar System Research in Göttingen, Germany, who has set up a team to analyse results from Rosetta.

Launched 10 years ago, Rosetta's mission is to make the first-ever landing on a comet. This latest discovery could complicate the mission.

It's not yet clear whether these are two different comets that have come together, or parts of a single comet that fractured but remained gravitationally bound.

More - Link >>> http://www.newscientist.com/article/dn25904-rosettas-target-comet-is-a-surprise-double-space-rock.html#.U87rvaKweKI

Source: New Scientist Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


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Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Sunday, July 20, 2014

45 Years Ago: Man Lands on the Moon !

http://www.nasa.gov/sites/default/files/62297main_neil_on_moon_full.jpg
The American Flag mounted at Tranquility Base on the Moon, after the landing of Apollo 11.
(Image Source: NASA)

By Glenn A. Walsh
Reporting for SpaceWatchtower

At the moment of this blog post, 45 years ago, man first landed on another planetary body, the Earth's Moon. On Sunday Afternoon, 1969 July 20 at 4:17:40 p.m. EDT / 20:17:40 Coordinated Universal Time, the Lunar Excursion Module (LEM) named "Eagle," which included American Astronauts Neal Armstrong and Buzz Aldrin, landed in the Moon's Sea of Tranquility, with only 25 seconds of fuel left.

Upon landing, Neal Armstrong announced, "Houston, Tranquility Base here. The Eagle has landed." Charles Duke, the CAPCOM (Capsule Communicator in the Johnson Space Flight Center in Houston). replied, "Roger, Twan— Tranquility, we copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot."

The mission schedule called for the lunar astronauts to have a five hour sleep period, before preparing for walking on the Moon, due to the hectic schedule they had followed for landing the LEM on the Moon. However, both astronauts chose to forgo the sleep period, as they felt they probably could not get to sleep anyway.

Originally, the first walks on the Moon, by the two astronauts, had been scheduled for the early morning hours, North American time, of Monday ("Moonday" - the day of the week actually named for the Moon), July 21. However, with the elimination of the early sleep period, the astronauts started immediately to prepare for stepping onto the lunar surface. This eventually allowed the first steps on the Moon to be seen on live television throughout the world, at the end of the Sunday evening prime-time television period in the Eastern Time Zone of North America (and even earlier for the rest of the United States), instead of during the middle-of-the-night in North America as was originally scheduled.

Neal Armstrong first opened the door of the LEM late Sunday Evening, 1969 July 20 at 10:39 p.m. EDT / July 21, 2:39 UTC. He set foot on  the Moon at precisely 10:56:20 p.m. EDT / July 21, 2:56:20 UTC (hence, by the time scale used by most scientists, Coordinated Universal Time, the first step on the Moon did occur on "Moonday"), saying the now historic words, "That's one small step for [a] man, one giant leap for mankind."

There is some debate (as described in news articles listed below in "Related Blog Posts") as to whether Neal Armstrong's now famous quote said "one small step for man" or "one small step for a man." However, there was no doubt in the minds of millions of television viewers on Earth (the television audience for this event has been estimated to be at least 600 million, worldwide) that two Americans had walked on the Moon.

On 1969 July 20, the Moon was a waxing crescent phase, with 31 percent of the Moon's visible disk illuminated. The lunar phase of First Quarter did not occur until July 22 at 8:10 a.m. EDT / 12:10 UTC. Of course, the Sea of Tranquility, where the Apollo 11 LEM landed, was within this 31 percent of the illuminated Moon, as viewed from Earth.

That day in Pittsburgh, the Moon rose at 11:57 a.m. EDT / 15:57 UTC and set at 11:44 p.m. EDT / July 21, 3:44 UTC. So, at the time of the first steps of men on the Moon, the Moon was still visible in the sky in Pittsburgh, and in most of North America, weather-permitting.

More on the historic mission of Apollo 11:
Link 1 >>> http://www.nasa.gov/externalflash/apollo40/
Link 2 >>> http://www.nasa.gov/apollo45/
Link 3 >>> http://en.wikipedia.org/wiki/Apollo_11

NASA commemorates the historic flight of Apollo 11:
Link >>> http://www.jpl.nasa.gov/news/news.php?release=2014-229&utm_source=iContact&utm_medium=email&utm_campaign=NASAJPL&utm_content=daily20140715

Photograph of Astronaut Neal Armstrong about to step on the Moon for the first time, from the live television broadcast:
Link >>> http://spacewatchtower.blogspot.com/2014/07/astronomical-calendar-2014-july.html

The Historic Mission of Apollo 11, Man Walks on the Moon for the First Time
A Personal Remembrance From 40 Years Ago By Glenn A. Walsh (2009 July):
Link >>> http://buhlplanetarium2.tripod.com/bio/Apolloremembrance.htm

Related Blog Posts ---

45th Anniversary: Apollo 8 Orbits the Moon Christmas Eve  (2013 Dec. 24):

Link >>> http://spacewatchtower.blogspot.com/2013/12/45th-anniversary-apollo-8-orbits-moon.html

 

JFK: Loss of the Man Who Sent Us to the Moon  (2013 Nov. 22):

Link >>> http://spacewatchtower.blogspot.com/2013/11/jfk-loss-of-man-who-sent-us-to-moon.html

 

Moon Day - A National Holiday ?  (2013 July 20):

Link >>> http://spacewatchtower.blogspot.com/2013/07/moon-day-national-holiday.html

 

Famous Moon Landing Quote Scrutinized by Scientists  (2013 June 2):

Link >>> http://spacewatchtower.blogspot.com/2013/06/famous-moon-landing-quote-scrutinized.html

 

Neil Armstrong's First Words on Moon: Brother Claims Scripted  (2013 Jan. 3):

Link >>> http://spacewatchtower.blogspot.com/2013/01/neil-armstrongs-first-words-on-moon.html

 

1st Man on Moon Dies at 82  (2012 Aug. 25):
Link >>> http://spacewatchtower.blogspot.com/2012/08/1st-man-on-moon-dies-at-82.html

 

Most U.S. Flags on Moon Still Standing  (2012 July 28):

Link >>> http://spacewatchtower.blogspot.com/2012/07/most-us-flags-on-moon-still-standing.html

 

Source: Glenn A. Walsh, Reporting for SpaceWatchtower, a project of Friends of the Zeiss.


2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Thursday, July 17, 2014

Solar Sail Spacecraft Test in 2016








LightSail is designed to be the first mission
to demonstrate controlled solar sailing for
small, affordable spacecraft called cubesats.
Josh Spradling / The Planetary Society
LightSail 1 will launch onboard SpaceX’s Falcon Heavy rocket to demonstrate propellant-free propulsion.

By Clara Moskowitz

Just as sailboats use wind pressure to propel through water, solar sails use the pressure from light radiated by the sun to move through space. Once the province of science fiction authors such as Arthur C. Clarke, solar sailing is gradually moving into the realm of reality. A privately funded $4.5-million mission to test solar sailing technology called LightSail now has a launch date in April 2016 and a ride to space onboard SpaceX’s Falcon Heavy rocket. Once in orbit, LightSail 1 will make maneuvers using sunlight, rather than rocket fuel. “Solar sailing has been under development at a slow pace for a lot of years,” says LightSail Project Manager Doug Stetson of the nonprofit Planetary Society, which is organizing and funding the mission. “The reason it’s hung on all these years is because of the potential for basically free propulsion throughout the solar system.”

LightSail 1 is a small spacecraft made of a stock of three 10-centimeter-wide squares called cubesats. After being carried to medium Earth orbit—more than 2,000 kilometers above the planet, high enough to escape most of its atmospheric drag—LightSail 1 will deploy four ultrathin Mylar sails that will stretch to 32 square meters (potentially large enough for naked-eye observers to spot from the ground). These sails will be bombarded with sunlight and each light particle, or photon, that impacts them will impart a tiny bit of momentum. Added up, those tiny bits should be enough to move the spacecraft without the need for heavy and expensive chemical propellant. If LightSail’s orbital speed increases once it deploys its sail, engineers will know it works.

In theory, solar sailing should be powerful enough to propel a spacecraft out of Earth orbit and into the solar system. “The disadvantage to that is it takes a long time [to move], just like it takes a lot longer to sail to the Bahamas than drive a speedboat,” Stetson says. Still, in space beyond Earth’s atmosphere without friction to stop it, once a solar sail gets going, it keeps accelerating as long as sunlight keeps hitting it. That makes solar sails an appealing option to explore the whole of the solar system and beyond. Many experts say they’re the likeliest candidate to propel the first interstellar mission to another star, with extra thrust supplied by a laser, perhaps stationed in orbit around the sun, aimed at the sail in addition to sunlight. One downside, however, is that solar sails don’t come with brakes or any means of changing trajectory or slowing down once they’re zooming. One possible solution is using a planet or star’s gravity to decelerate the craft or slingshot it along a desired path.

More - Link >>> http://www.scientificamerican.com/article/lightsail-solar-sailing-launch-date/?&WT.mc_id=SA_DD_20140716

Source: Scientific American Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Tuesday, July 15, 2014

NASA Visits Pluto in 2015, Plans Visit to Jupiter Moon Europa

Compiled from NASA’s Galileo spacecraft data, this colorized surface image of Europa shows the blue-white terrains which indicate relatively pure water ice.
Compiled from NASA’s Galileo spacecraft data, this colorized surface image of Europa shows the blue-white terrains which indicate relatively pure water ice. Scientists are very interested in these features because they may offer a way to investigate the habitability of the moon’s interior ocean.
Image Credit: 
NASA/JPL-Caltech/SETI Institute

With one year to go before the New Horizons spacecraft encounters Pluto, NASA has started planning for a mission to Jupiter's Moon Europa.

In July 2015, NASA will discover a new world.  No one knows what to expect when the alien landscape comes into focus.  There could be icy geysers, towering mountains, deep valleys, even planetary rings.

At this point, only one thing is certain:  Its name is Pluto.

On July 14th, 2015, NASA's New Horizons spacecraft will make a close flyby of that distant world. "Because Pluto has never been visited up-close by a spacecraft from Earth, everything we see will be a first," says Adriana Ocampo, the Program Executive for NASA's New Frontiers program at NASA headquarters. "I know this will be an astonishing experience full of history making moments."

More - Link >>> http://science.nasa.gov/science-news/science-at-nasa/2014/14jul_pluto2015/

NASA has issued an Announcement of Opportunity (AO) for proposals about science instruments that could be carried aboard a future mission to Jupiter’s moon Europa. Selected instruments could address fundamental questions about the icy moon and the search for life beyond Earth.

“The possibility of life on Europa is a motivating force for scientists and engineers around the world,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This solicitation will select instruments which may provide a big leap in our search to answer the question: are we alone in the universe?”

The Decadal Survey deemed a mission to Europa among the highest priority scientific pursuits for NASA. It listed five key science objectives in priority order that are necessary to improve our understanding of the potentially habitable moon:

  • Characterize the extent of the ocean and its relation to the deeper interior
  • Characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange
  • Determine global surface, compositions and chemistry, especially as related to habitability
  • Understand the formation of surface features, including sites of recent or current activity, identify and characterize candidate sites for future detailed exploration
  • Understand Europa’s space environment and interaction with the magnetosphere.

More - Link >>> http://www.nasa.gov/press/2014/july/nasa-seeks-proposals-for-europa-mission-science-instruments/#.U8WXJaKweKI

Source: NASA.

2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Friday, July 11, 2014

July's Buck Moon & High Tides



By Glenn A. Walsh
Reporting for SpaceWatchtower

One of the largest Full Moons of the year, which may affect the tides, occurs Saturday Morning. The Full Moon of July occurs 2014 July 12 at 7:25 a.m. EDT / 11:25 Coordinated Universal Time.

Due to the fact that this Full Moon occurs less than 24 hours before lunar perigee, the Moon's closest approach to the Earth this month, it will be one of the closest, and appear as one of the largest, Full Moons of 2014.

When a Full Moon closely aligns with a lunar perigee, some people refer to it as a "SuperMoon." However, the Full Moon of August will actually appear as the largest "SuperMoon" of 2014.

Lunar perigee occurs early Sunday Morning, 2014 July 13 at 4:00 a.m. EDT / 8:00 UTC, when the Moon will be only 358,260 kilometers from the Earth.

In addition to appearing a wee bit larger in the sky, it is also predicted that this Full Moon close to lunar perigee will result in larger than usual high tides near ocean coastlines.

As we recently passed the Summer Solstice on June 21, when the season of Summer officially began, the Sun appears the highest in the sky during these Summer months (the primary reason Summer months are so much warmer than other months of the year). In astronomical terms, the Sun has a high or positive declination in the sky. Consequently, this is also the season when the Moon appears the lowest in the sky, with a low declination. At this time of year, the Sun is in the sky almost 15 hours every day (another reason Summer months are so warm) while the Moon appears in the sky less than 10 hours a day.

The July Full Moon is known as the Buck Moon, as it usually occurs around the time bucks are beginning to grow new antlers. Some people refer to the July Full Moon as the Thunder Moon, due to the many electrical storms prevalent during the "Dog Days of Summer," approximately July 3 to August 11.

Native Americans also referred to the July Full Moon as the Hay Moon, Buffalo (Bull) Moon, and the Hot Sun Moon.

In the Southern Hemisphere, the July Full Moon is known as the Wolf Moon, Old Moon, and Ice Moon.

More on astronomical declination: Link >>> http://en.wikipedia.org/wiki/Declination

More on the so-called "SuperMoon": Link >>> http://en.wikipedia.org/wiki/Supermoon

More on the Full Moon: Link >>> http://en.wikipedia.org/wiki/Full_moon

More on Full Moon names ---
Link 1 >>> http://earthsky.org/astronomy-essentials/full-moon-names
Link 2 >>> http://en.wikipedia.org/wiki/Full_moon#Harvest_and_Hunter.27s_moons
Link 3 >>> http://www.farmersalmanac.com/full-moon-names/

Source: Glenn A. Walsh, Reporting for SpaceWatchtower, a project of Friends of the Zeiss.


2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Tuesday, July 8, 2014

Iron Richness Hints at Mercury's Violent Creation

Mercury in a false-color NASA image
Cosmic collisions reason why Mercury is a "freak" among solar system's rocky planets, scientists say. Planet has more iron than it should, they explain.
(Photo : NASA)



By Jim Algar, Tech Times

A giant "hit and run" impact with another planet billions of years in the past may explain the unexpected and mysterious internal makeup of Mercury, the solar system's closest planet to the sun, researchers say.

The mystery is that a small planet shouldn't have as much iron as has been observed on Mercury, they say. The Earth, Mars and Venus -- the solar system's other rocky worlds -- are about 30 percent iron.

So why is Mercury almost 60 percent iron?

The answer may be down to a particularly violent "childhood" in which Mercury was involved in a number of impacts that stripped away much of the materials other than iron that we would expect to see there, planetary scientists Erik Asphaug of the University of Arizona says in a study published in the journal Nature Geoscience.

More - Link >>> http://www.techtimes.com/articles/9969/20140708/mercurys-rocky-childhood-one-reason-iron-richness.htm

Source: TechTimes.com .

2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >

Saturday, July 5, 2014

Cosmic Cold Spot: 'Hole' in Universe?

Get WISE to voids <i>(Image: NASA/JPL-Caltech/UCLA)</i>
Get WISE to voids (Image: NASA/JPL-Caltech/UCLA)

By Maggie McKee

IT HAS been called a bruise on the sky – a curious cold spot in the afterglow of the big bang that has sparked wild cosmic theories attributing it to a run-in with another universe or a wrinkle in space-time.

Now it seems the answer may be a little more mundane: the biggest known hole in the universe.

The cold spot appears in maps of the cosmic microwave background (CMB), the earliest light emitted in the universe. Temperature variations in the light show up as a mottled pattern in the maps, which can be explained if quantum fluctuations at the universe's birth were stretched out by a brief but spectacular cosmic growth spurt known as inflation.

But some features in the maps don't fit into the leading models of inflation. For example, the relatively even pattern of the CMB is marred by an unusually large cold region. Scientists have struggled to explain it, suggesting a number of ideas that require exotic physics or even evidence for a multiverse.

A much simpler explanation is that the cold spot is caused by a giant void in the universe. The cosmos consists of a web of bright galaxies and clusters surrounded by dark pockets that contain little matter. Radiation loses energy when it crosses these empty regions, so a large void could cause a cold spot in our CMB maps. But most surveys haven't looked at a wide enough region of the sky to be able to find such a void relatively close to Earth. One study that claimed to have discovered one in 2007 was later disputed.

More - Link >>> http://www.newscientist.com/article/mg22329762.800-biggest-void-in-universe-may-explain-cosmic-cold-spot.html#.U7hQRCdyyKI

Source: New Scientist Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium Historic Zeiss II Planetarium Projector at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.


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gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >