SpaceWatchtower: August 2014

Saturday, August 30, 2014

Supernovas Near Earth 10 Million Years Ago

Once every 50 years, more or less, a massive star explodes somewhere in the Milky Way. The resulting blast is terrifyingly powerful, pumping out more energy in a split second than the sun emits in a million years. At its peak, a supernova can outshine the entire Milky Way.

It seems obvious that you wouldn't want a supernova exploding near Earth. Yet there is growing evidence that one did—actually, more than one. About 10 million years ago, a nearby cluster of supernovas went off like popcorn. We know because the explosions blew an enormous bubble in the interstellar medium, and we're inside it.

A new ScienceCast video examines evidence that our solar system is inside a bubble of hot gas created by supernova explosions. Play it

Astronomers call it "the Local Bubble." It is peanut-shaped, about 300 light years long, and filled with almost nothing. Gas inside the bubble is very thin (0.001 atoms per cubic centimeter) and very hot (roughly a million degrees)—a sharp departure from ordinary interstellar material.

More - Link >>> http://science.nasa.gov/science-news/science-at-nasa/2014/26aug_localbubble/

Source: NASA Science News.

2014: 75th Year of Pittsburgh's Buhl Planetarium

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 >
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/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
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, August 28, 2014

Extrasolar Asteroid Smashup Seen by NASA Telescope

This artist's concept shows the immediate aftermath of a large asteroid impact around NGC 2547-ID8, a 35-million-year-old sun-like star thought to be forming rocky planets.
Image credit: NASA/JPL-Caltech › Full image and caption

NASA's Spitzer Space Telescope has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the formation of planets.

Scientists had been regularly tracking the star, called NGC 2547-ID8, when it surged with a huge amount of fresh dust between August 2012 and January 2013.

"We think two big asteroids crashed into each other, creating a huge cloud of grains the size of very fine sand, which are now smashing themselves into smithereens and slowly leaking away from the star," said lead author and graduate student Huan Meng of the University of Arizona, Tucson.

While dusty aftermaths of suspected asteroid collisions have been observed by Spitzer before, this is the first time scientists have collected data before and after a planetary system smashup. The viewing offers a glimpse into the violent process of making rocky planets like ours.

More - Link >>> http://www.jpl.nasa.gov/news/news.php?release=2014-291

Sources: NASA, Jet Propulsion Laboratory / California Institute of Technology.

2014: 75th Year of Pittsburgh's Buhl Planetarium

Tuesday, August 26, 2014

New Project Searches for ET Waste Heat

So bright, the aliens need shades <i>(Image: NASA/JPL-CALTECH/UCLA/Science Photo Library)</i>

(Image: NASA/JPL-CALTECH/UCLA/Science Photo Library)

By Rachel Ehrenberg

RATHER than searching for aliens phoning home, scientists are looking for signs of the homes themselves. A new project proposing that galaxy-spanning alien civilisations should generate detectable heat has turned up a few dozen galaxies that hold promise as harbours for life.

The best-known technique used to search for tech-savvy aliens is eavesdropping on their communications with each other. But this approach assumes ET is chatty in channels we can hear.

The new approach, dubbed G-HAT for Glimpsing Heat from Alien Technologies, makes no assumptions about what alien civilisations may be like.

"This approach is very different," says Franck Marchis at the SETI Institute in California, who was not involved in the project. "I like it because it doesn't put any constraints on the origin of the civilisation or their willingness to communicate."

More - Link >>> http://www.newscientist.com/article/mg22329831.600-spot-ets-waste-heat-for-chance-to-find-alien-life.html#.U_0fI7HClco

Source: New Scientist Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium

Saturday, August 23, 2014

Solar Storms May Have Altered Lunar Soil

This illustration shows a permanently shadowed region of the moon undergoing subsurface sparking (the "lightning bolts"), which ejects vaporized material (the "clouds") from the surface. Subsurface sparking occurs at a depth of about one millimeter. Image not to scale. Image: Andrew Jordan

By David Sims, University of New Hampshire

The moon appears to be a tranquil place, but modeling done by Univ. of New Hampshire and NASA scientists suggests that, over the eons, periodic storms of solar energetic particles may have significantly altered the properties of the soil in the moon’s coldest craters through the process of sparking—a finding that could change our understanding of the evolution of planetary surfaces in the solar system.

The study, published recently in the Journal of Geophysical Research-Planets, proposes that high-energy particles from uncommon, large solar storms penetrate the moon’s frigid, polar regions and electrically charge the soil. The charging may create sparking, or electrostatic breakdown, and this “breakdown weathering” process has possibly changed the very nature of the moon’s polar soil, suggesting that permanently shadowed regions, which hold clues to our solar system’s past, may be more active than previously thought.

More - Link >>> http://www.rdmag.com/news/2014/08/electric-sparks-may-alter-evolution-lunar-soil?et_cid=4113094&et_rid=544605860&location=top

Sources: University of New Hampshire, R & D Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium

Thursday, August 21, 2014

Cassini Spacecraft: Saturn Rings Older Than First Thought

Saturn's iconic rings seem to have formed
early in the planet's history.
Credit: CICLOPS/JPL/ESA/NASA

By Alexandra Witze and Nature magazine

Saturn’s spectacular ring system may date back some 4.4 billion years to the time when the planet itself formed, new findings suggest. The work could help to resolve a long-running debate about whether the rings are ancient or formed much more recently, on the order of hundreds of millions of years ago.

For the first time, NASA's Cassini spacecraft has measured the rate at which dust from outside the Saturn system is falling on the rings and polluting them. That rate turns out to be about 40 times lower than previously thought, which eliminates a major argument against the ‘old rings’ theory: that if the rings had been around for billions of years, they should have gotten coated with a dark spray of other particles and look a lot dirtier than they do.

"The rings can be three to ten times older than we used to think," says Larry Esposito, a planetary scientist at the University of Colorado Boulder.

More - :Link >>> http://www.scientificamerican.com/article/dust-reveals-ancient-origin-for-saturn-s-rings/?&WT.mc_id=SA_DD_20140821

Sources: Nature Magazine, Scientific American Magazine.

Biography of Allegheny Observatory Director James E. Keeler, who discovered the true composition of Saturn's Rings in 1895:
Link >>> http://johnbrashear.tripod.com/bio/KeelerJ.htm

2014: 75th Year of Pittsburgh's Buhl Planetarium

Tuesday, August 19, 2014

Help NASA Classify Pix From Space

One of the images from space in large NASA photo collection.
(Image Source: NASA)

By Eliott C. McLaughlin, CNN

NASA is asking for your help.

No, you do not get to go to space.

You do, however, get to view hundreds of thousands of images taken from space. Via The Gateway to Astronaut Photography of Earth, NASA is making available images ranging from the Mercury missions of the 1960s to photos recently snapped from the International Space Station.

The Complutense University of Madrid is spearheading efforts to catalog the photos and corral citizen input. It's broken the images into three components requiring different levels of participation:

1. Dark skies. This is the easiest project, as it requires no scientific expertise. "Anyone can help" by sorting the images into the categories: cities, stars or other objects, said Alejandro Sanchez, doctoral student at Complutense.

"Without the help of citizens, it is almost impossible to use these images scientifically. Algorithms cannot distinguish between stars, cities and other objects, such as the moon. Humans are much more efficient for complex image analysis," he said.

2. Night cities. Looking at night images, citizen scientists can tap their knowledge of local geography to match photos with positions on maps. Residents of a city can more easily identify a city's features than those who don't live there, Sanchez said. The data will be used to generate light maps of cities.

3. Lost at night. This is the trickiest, as it aims to identify cities in photos with 310-mile circumferences.

More - Link >>> http://www.cnn.com/2014/08/17/tech/nasa-earth-images-help-needed/

Gateway to Astronaut Photography of Earth: Link >>> http://eol.jsc.nasa.gov/

Sources: NASA, CNN.

2014: 75th Year of Pittsburgh's Buhl Planetarium

Saturday, August 16, 2014

Beautiful Morning Conjunction of Planets

Sleeping late is one of the simple pleasures of summer vacation. This week, waking up early will be a pleasure, too.

Set your alarm for 30 minutes before sunrise. Venus and Jupiter are converging in the dawn sky for a beautiful conjunction that will wake you up faster than a cup of strong coffee. To see it, you'll need a clear view of the east-northeastern horizon and … that's all. No telescope is required. These are the two brightest planets in the Solar System, and they are visible to the naked eye even from light-polluted cities.

A new ScienceCast video previews the spectacular morning conjunction of August 18, 2014. Play it

More - Link >>> http://science.nasa.gov/science-news/science-at-nasa/2014/15aug_conjunction/

Source: NASA Science News.

2014: 75th Year of Pittsburgh's Buhl Planetarium

Thursday, August 14, 2014

Gravity Anomaly May Protect Earth From Asteroids

Asteroid 1950 DA. Image: NASA
Researchers at the University of Tennessee at Knoxville have made a novel discovery that may potentially protect the world from future collisions with asteroids.

The team studied near-Earth asteroid 1950 DA and discovered that the body, which rotates so quickly it defies gravity, is held together by cohesive forces, called van der Waals, never before detected on an asteroid

“Following the February 2013 asteroid impact in Chelyabinsk, Russia, there is renewed interest in figuring out how to deal with the potential hazard of an asteroid impact,” said Ben Rozitis, a postdoctoral researcher in the University's Department of Earth and Planetary Sciences. “Understanding what holds these asteroids together can inform strategies to guard against future impacts.”

More - Link >>> http://www.laboratoryequipment.com/news/2014/08/gravity-find-may-protect-earth-asteroids?et_cid=4099217&et_rid=544605860&type=image

Sources: University of Tennessee at Knoxville, LaboratoryEquipment.com .

Related Blog Post ---

Laser Satellite to Defend Earth from Asteroid Impacts? (2014 Jan. 11):

Link >>> http://spacewatchtower.blogspot.com/2014/01/laser-satellite-to-defend-earth-from.html

2014: 75th Year of Pittsburgh's Buhl Planetarium

Tuesday, August 12, 2014

Perseid Meteor Shower Peaks in Sky & Web-Casts

A new ScienceCast video previews the competition between the SuperMoon of August and the 2014 Perseid meteor shower. Play it (Image / Video Source: NASA Science News)

By Glenn A. Walsh
Reporting for SpaceWatchtower

The time of posting of this blog post (August 12, 8:00 p.m. EDT / August 13, 0:00 Coordinated Universal Time) is the actual peak time of the the most famous and best observed meteor shower of the year. The Perseid Meteor Shower always peaks sometime during the night / early morning of August 12 to 13.

During the peak time, often 50 to 80 meteors can be seen per hour, if observing conditions are ideal. To see these meteors you need to be away from city lights, as artificial lighting can often drown-out the dimmer meteors.

However, the "SuperMoon," a Full Moon at the closest point to the Earth in 2014, which occurred this-past weekend, means that some of the dimmer meteors will be drowned-out by the brightness of this so-called SuperMoon. But, the Perseid Meteor Shower is one of the year's best meteor showers for fireballs, huge meteors which seem to explode in the upper atmosphere; so these can be seen even in bright moonlight.

The debris which forms the Perseid Meteor Shower comes from the Comet Swift Tuttle, which swings into the inner part of our Solar System every 133 years, leaving behind a trail of dust and grit.

Although the time of this blog posting is the peak of the Perseid Meteor Shower, it is hardly the best time for viewing meteors in North America, considering that the vast majority of the continent has not yet experienced sunset this day. However, even after sunset, you may want to wait a little while before going out to look for meteors. The best time to view a meteor shower is always between local midnight and dawn, when our planet is actually rotating into the meteor shower.

Binoculars and telescopes are not very useful for finding meteors. Meteors streak across the sky in a very short period of time, too short to aim binoculars or a telescope. So, the best way to view a meteor shower is to lie on the ground, in an area with a good view of the entire sky (with few obstructions such as buildings, trees or hills), and keep scanning the entire sky.

Meteor showers appear to emanate from a radiant point in the sky. For the Perseid Meteor Shower, the radiant appears to be the Constellation Perseus. However, you should not, necessarily, be looking only at Perseus, when looking for meteors in this shower. Meteors can appear in any part of the sky at any time.

Of course, meteor showers. like all celestial observations, are weather-permitting. If the weather in your area does not permit direct viewing outdoors of this meteor shower, it can be viewed during special web-casts at a couple sites on the Internet.

Internet Sites to View the Perseid Meteor Shower Near Peak, August 12 to 13:

Slooh Community Observatory: Link >>> http://live.slooh.com/

NASA Marshall Spaceflight Center:
Link >>> http://www.nasa.gov/watchtheskies/perseids-2014.html

NASA Science News - Perseid Meteors vs. the Supermoon:
Link >>> http://science.nasa.gov/science-news/science-at-nasa/2014/28jul_perseids2014/

History of the Perseid Meteor Shower:
Link >>> http://meteorshowersonline.com/perseids.html

Related Blog Posts ---

Another 'SuperMoon' (2014 Aug. 9):

Link >>> http://spacewatchtower.blogspot.com/2014/08/another-supermoon.html

Moon Set Favors July Meteor Shower; Also Web-Casts (2014 July 26):

Link >>> http://spacewatchtower.blogspot.com/2014/07/moon-set-favors-july-meteor-shower-also.html

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

2014: 75th Year of Pittsburgh's Buhl Planetarium

Saturday, August 9, 2014

Another 'SuperMoon'

By Glenn A. Walsh
Reporting for SpaceWatchtower

Yes, it is another "SuperMoon" this month, as some people refer to it.

Actually, the August Full Moon occurs very near the monthly perigee, or closest point in the Moon's orbit of the Earth. And while the Full Moon of July was considered a "SuperMoon" as will the Full Moon of September, this month the Moon will be closer to the Earth, and appear larger in the sky, than at any other time in 2014.

Since the Moon is closer to Earth than it typically is, the Moon looks a bit larger than usual in the sky, particularly near the horizon during Moon rise and Moon set (actually, the Moon always looks a little bigger during Moon rise and Moon set, as people's vision then compares the size of the Moon to other objects near the horizon).

The August Full Moon occurs on Sunday Afternoon, 2014 August 10 at 2:09 p.m. EDT / 18:09 Coordinated Universal Time. About nine minutes earlier, the Moon will have reached the point in its orbit of perigee, when it is only 356,896 kilometers from the Earth. Due to this Full Moon perigee, larger-than-normal high-tides are predicted along ocean coastlines on Sunday.

The Full Moon of August is known as the Sturgeon Moon in the Northern Hemisphere. It was so named by the Native American fishing tribes of northern North America, particularly around the Great Lakes, as this fish was most readily caught during the month of August.

Other tribes knew the August Full Moon as the Red Moon, due to the Moon's reddish appearance as it rises in the mid-Summer's humid haze. This Full Moon was also known as the Green Corn Moon or just Corn Moon and the Grain Moon for crops readying for harvest, as well as the Cow Buffalo Moon. And, there is record of some tribes calling it the Harvest Moon, while most tribes kept this designation for the September Full Moon.

In the Southern Hemisphere, the August Full Moon is known as the Snow Moon, Storm Moon, Hunger Moon, and Wolf Moon.

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/

Related Blog Post ---

July's Buck Moon & High Tides (2014 July 11):

Link >>> http://spacewatchtower.blogspot.com/2014/07/julys-buck-moon-high-tides.html

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

2014: 75th Year of Pittsburgh's Buhl Planetarium

Thursday, August 7, 2014

After a Decade European Space Probe Reaches Comet

Today, after a decade-long journey chasing its target, the European Space Agency's Rosetta probe, carrying three NASA instruments, became the first spacecraft to rendezvous with a comet, 67P/Churyumov-Gerasimenko.

"After 10 years, five months and four days travelling towards our destination, looping around the sun five times and clocking up 6.4 billion kilometers, we are delighted to announce finally we are here," said Jean-Jacques Dordain, ESA's director General.

Comet 67P/Churyumov-Gerasimenko by Rosetta’s OSIRIS narrow-angle camera on August 3, 2014, from a distance of 177 miles (285 kilometers). Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA Full image and caption

The latest images of the comet taken by Rosetta are available at http://www.nasa.gov/rosetta

Comet 67P/Churyumov-Gerasimenko and Rosetta are 252 million miles (405 million kilometers) from Earth, about halfway between the orbits of Jupiter and Mars. The comet is in an elliptical, 6.5-year orbit that takes it from beyond Jupiter at its farthest point, to between the orbits of Mars and Earth at its closest to the sun. Rosetta will accompany the comet for over a year as it swings around the sun and back out towards Jupiter again.

Rosetta is 62 miles (100 kilometers) from the comet's surface. Over the next six weeks, it will fly two triangular-shaped trajectories in front of the comet.

More - Link >>> http://science.nasa.gov/science-news/science-at-nasa/2014/06aug_rosetta6/

Source: NASA Science News.

Related Blog Post ---

European Space Probe Aims for 1 Comet, Finds 2 (2014 July 22):

Link >>> http://spacewatchtower.blogspot.com/2014/07/european-space-probe-aims-for-1-comet.html

2014: 75th Year of Pittsburgh's Buhl Planetarium

Tuesday, August 5, 2014

Will Earth Fossils Be Found on the Moon?

by Jacob Aron

Signs of ancient life could be littered across the moon, just waiting for an intrepid explorer to find them. That's according to physicists who tested what would happen if a chunk of rock containing microscopic fossils from Earth were to be launched into space and smash into the lunar surface. Finding one could give us a pristine glimpse into past life on Earth.

Meteorites found on Earth that were created by impacts on the moon and Mars suggest that cosmic bodies regularly chuck rocks at each other. A few researchers have claimed that some of these meteorites show signs of fossilised bacteria, the most famous being Mars rock ALH 84001. However, the evidence is shaky – and misses a more fundamental question, says Mark Burchell at the University of Kent, UK.

"No one ever seems to have asked, even if the fossils did exist in a rock, would they survive?" he says. To find out, Burchell and his colleagues tried to simulate the conditions that fossilised diatoms – microscopic algae with detailed shells – would face on a trip from here to the moon.

More - Link >>> http://www.newscientist.com/article/dn25961-ancient-earth-fossils-could-be-found-on-the-moon.html#.U-FFfqKwe4I

Source: New Scientist Magazine.

2014: 75th Year of Pittsburgh's Buhl Planetarium

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, August 1, 2014

Astronomical Calendar: 2014 August

Image of one of the first practical photographic cameras. This Daguerreotype camera was built by La Maison Susse Frères in 1839, with a lens by Charles Chevalier. August 19 marks the 175th anniversary of the release of the first practical photographic process patent.
More information: http://www.worldphotoday.org/ (Image Source: Wikipedia.org )

Astronomical Calendar for 2014 August:

Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2014.html#aug

The current month's Astronomical Calendar can also be found on the cover page of the History of The Buhl Planetarium and Institute of Popular Science, Pittsburgh web site at this link:

Link >>> http://buhlplanetarium.tripod.com/#astrocal

Source: Friends of the Zeiss.

2014: 75th Year of Pittsburgh's Buhl Planetarium

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 >