Space Junk Tracking to be Hindered by Shutdown of USAF 'Space Fence'

This computer illustration depicts the density of space junk around Earth in low-Earth orbit. Image: ESA

WASHINGTON — The U.S. Air Force's decision to shut down a key component of its Space Surveillance Network will weaken the service's ability to accurately detect and characterize objects in Earth orbit, experts say.

The space fence shutdown, ordered by Gen. William Shelton, commander of Air Force Space Command, also will reduce the overall capacity of the system, these experts said. At the same time, they suggested it could increase pressure on the Air Force to award a contract on a next-generation system, which has stalled amid a Pentagon-wide review of its acquisition plans.

According to two recent memos obtained by SpaceNews, the Air Force will shut down the aging Air Force Space Surveillance System, also known informally as the Space Fence, Sept. 1. The memos, from Austin Frindt, a contracting officer with Air Force Space Command, were addressed to Five Rivers Services of Colorado Springs, Colo., operator of the current Space Fence, which consists of a line of VHF radars stretching across the southern United States.

Deployed in the 1960s, the VHF Space Fence includes three transmitter sites and six receiving stations. It is responsible for approximately 40 percent of all observations performed by the Air Force-run Space Surveillance Network, which includes other ground-and space-based sensor assets, said Brian Weeden, technical adviser at the Secure World Foundation, a nonprofit organization dedicated to space sustainability.

More - Link >>> http://www.scientificamerican.com/article.cfm?id=us-militarys-space-fence&WT.mc_id=SA_DD_20130814

Sources: SpaceNews, Tech Media Network, Scientific American Magazine.

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Glenn A. Walsh, Project Director,
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More FREE NASA Books

By Glenn A. Walsh
Reporting for SpaceWatchtower

 Last week, I reported on "NASA's Massive Free E-Book Collection":

Link >>> http://spacewatchtower.blogspot.com/2013/08/nasas-massive-free-e-book-collection.html

Richard Spencer, Information Services Manager for the Library at NASA Headquarters in Washington has informed me of more free NASA E-Books, and also some free regular books in celebration of 50 years of NASA.  Here is the message he sent me:

By the way, let your readers know that the Aeronautics Research Mission Directorate is also building a collection of free ebooks at http://www.aeronautics.nasa.gov/ebooks. 

 

Also, I oversee the Headquarters Information Center which distributes and sells the books to the public.  Currently, the History Program Office is celebrating 50 years of publishing books with a massive giveaway of many titles.  The price page (including which titles are available for free) is at: http://www.hq.nasa.gov/office/hqlibrary/ic/ic2.htm. We’re distributing them for a $3.00 per book shipping/handling fee (or visitors can walk in for copies – although we will be closing to public access for 9 months beginning Aug 21^st.)

 

Rick

 

Richard Spencer

Information Services Manager, BFJV, Inc.

Library, Information Center, Historical Reference Center

NASA Headquarters

300 E St. SW, Rm 1J22

Washington, DC 20546

(202) 358-0168

http://www.hq.nasa.gov/office/hqlibrary

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

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Glenn A. Walsh, Project Director,
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Electronic Mail - < gawalsh@planetarium.cc >
About the SpaceWatchtower Editor/Author: < http://buhlplanetarium.tripod.com/#GAW >
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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 >
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  < http://inclinedplane.tripod.com >
* Public Transit:
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Perseid Meteor Shower Peaks Sun., Mon. Nights

By Glenn A. Walsh
Reporting for SpaceWatchtower

The largest meteor shower of the year, the annual Perseid Meteor Shower, peaks Sunday and Monday nights. The actual peak is Monday afternoon at 2:00 p.m. EDT (18:00 Coordinated Universal Time), for those viewers where the Sun has already set.

A meteor shower normally consists of dust particles related to a comet. Each time a comet approaches the Sun, the comet loses dust particles following the melting of ice on the comet. These dust particles, called meteoroids, continue to follow the same orbit as the comet and form a meteoroid stream. Each year, as the Earth orbits the Sun, the Earth passes through several of these meteoroid streams, becoming Earth's meteor showers.

The Earth's gravity then attracts many of these meteoroids to fall to Earth, and they are viewed by people as meteors, as they burn-up in the atmosphere. Most are extremely small and burn-up completely. From time-to-time, larger particles enter the atmosphere and create brilliant displays known as fireballs. If these particles are large enough, they may not completely burn-up and land on Earth as a meteorite.

Meteors can be seen any night of the year, although they are not predictable and are rare outside of one of the annual meteor showers. The vast majority of meteors that can be seen during the Perseid Meteor Shower originate from the Comet Swift-Tuttle, which has an orbital period of 133 years. Comet Swift-Tuttle was discovered in 1862 and returned for viewing in 1992.

Comet Swift-Tuttle measures about 16-miles across, much larger than the object that is thought to have fallen to Earth which resulted in the extinction of the dinosaurs. Comet Swift-Tuttle will make a very close approach to the Earth in  the year 4479. Scientists are now studying whether some day Comet Swift-Tuttle could impact the Earth. Comet Swift–Tuttle has been described as "the single most dangerous object known to humanity".

Viewers in the Northern Hemisphere are fortunate that the Perseid Meteor Shower arrives during the Summer month of August, when temperatures are comfortable for nighttime viewing, although sometimes August can be very humid with poor seeing conditions.

It is best to look for the Perseids, or any meteor shower, after local midnight, when the Earth is then rotating toward the meteor shower. As most meteors are often dim, it is best to view a meteor shower away from city lights, which cause a brightening of the sky at night, and hence, the dimmest meteors are often missed. And, you want to go out ahead of time, before you start actual viewing of meteors, to get your eyes accustomed to the dark sky.

The Perseid Meteor Shower is named because the meteors appear to radiate from the Constellation Perseus. However, meteors can appear in any part of the sky at any time. In fact, looking  towards Perseus may not result in finding the best meteors, as meteors coming from the apparent radiant may be seen for a shorter time in the sky.

Telescopes and binoculars are really not useful when searching for meteors. You need a wide field-of-view to find a meteor. Hence, your best instrument for viewing meteors are simply your eyes!

More on the Perseid Meteor Shower: Link >>> http://en.wikipedia.org/wiki/Perseid

More on Meteor Showers: Link >>> http://en.wikipedia.org/wiki/Meteor_shower

More on Meteors: Link >>> http://en.wikipedia.org/wiki/Meteor#Meteor

More on Comet Swift-Tuttle: Link >>> http://en.wikipedia.org/wiki/Swift-Tuttle

Fifth largest fragment of the meteorite which struck Barringer Meteor Crater near Winslow, Arizona, which was displayed at Pittsburgh's original Buhl Planetarium and Institute of Popular Science:
Link >>> http://buhlplanetarium2.tripod.com/Buhlexhibits.htm#meteorite

Related Blog Post ---

NASA: Perseid Meteor Shower Has Most Fireballs  (2013 July 27):

Link >>> http://spacewatchtower.blogspot.com/2013/07/nasa-perseid-meteor-shower-has-most.html 

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

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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://buhlplanetarium.tripod.com/#GAW >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
< http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
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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:
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NASA's Massive Free E-Book Collection

Cosmonaut Pavel Belyayaev in 1965 from Rockets and People (Asif Siddiqi)

Alexis C. Madrigal Aug 8 2013

Behold, the hundreds of free e-books about space history contained on this webpage.

From old favorites like The Difficult Road to Mars: A Brief History of Mars Exploration in the Soviet Union and Wind Tunnels of NASA to experimental work like Aerospace Food Technology and Life in the Universe: Proceedings of a conference held at NASA Ames Research Center Moffet Field, California, June 19-20, 1979, this is one of the best collections of space arcana you're likely to find.

These books were placed online over the last decade, so some of the formatting leaves something to be desired. Many of the works have been broken up into tiny pieces, forcing one to click through page after page. But this is a singular information repository, a storehouse for our fascination with flight.

 More - Link >>> http://www.theatlantic.com/technology/archive/2013/08/nasas-massive-free-e-book-collection/278496/

Source: The Atlantic Magazine.

NASA History Series Publications - Free E-Books:
Link >>> http://history.nasa.gov/series95.html

 

Related Blog Post ---

 

More FREE NASA Books  (2013 Aug. 13):

Link >>> http://spacewatchtower.blogspot.com/2013/08/more-free-nasa-books.html

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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://buhlplanetarium.tripod.com/#GAW >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
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< 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 >

Sun's Magnetic Field About to Flip

Something big is about to happen on the sun.  According to measurements from NASA-supported observatories, the sun's vast magnetic field is about to flip.

"It looks like we're no more than 3 to 4 months away from a complete field reversal," says solar physicist Todd Hoeksema of Stanford University. "This change will have ripple effects throughout the solar system."

A new ScienceCast video anticipates the reversal of the sun's global magnetic field. Play it

The sun's magnetic field changes polarity approximately every 11 years.  It happens at the peak of each solar cycle as the sun's inner magnetic dynamo re-organizes itself.  The coming reversal will mark the midpoint of Solar Cycle 24. Half of 'Solar Max' will be behind us, with half yet to come.

Hoeksema is the director of Stanford's Wilcox Solar Observatory, one of the few observatories in the world that monitor the sun's polar magnetic fields.  The poles are a herald of change. Just as Earth scientists watch our planet's polar regions for signs of climate change, solar physicists do the same thing for the sun.

Magnetograms at Wilcox have been tracking the sun's polar magnetism since 1976, and they have recorded three grand reversals—with a fourth in the offing.

Astronomers at the Wilcox Solar Observatory (WSO) monitor the sun's global magnetic field on a daily basis. WSO home page

Solar physicist Phil Scherrer, also at Stanford, describes what happens: "The sun's polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity. This is a regular part of the solar cycle."

A reversal of the sun's magnetic field is, literally, a big event. The domain of the sun's magnetic influence (also known as the "heliosphere") extends billions of kilometers beyond Pluto. Changes to the field's polarity ripple all the way out to the Voyager probes, on the doorstep of interstellar space.

More - Link >>> http://science.nasa.gov/science-news/science-at-nasa/2013/05aug_fieldflip/

Source: NASA Science News.

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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://buhlplanetarium.tripod.com/#GAW >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
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Twitter: < https://twitter.com/spacewatchtower >
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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:
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Comet Graveyard Found in Asteroid Belt

These illustrations show the asteroid belt in the present day and in the early Solar System, located between the Sun (at centre) and four terrestrial planets (near the Sun) and Jupiter (at bottom left). The top image shows the conventional model for the asteroid belt; largely composed of rocky material. The middle image shows the proposed model, with a small number of active comets and a dormant cometary population. The lower diagram shows how the asteroid belt might have looked in the early Solar System, with vigorous cometary activity. (Credit: Ignacio Ferrin / University of Anitoquia)

A team of astronomers from the University of Anitoquia, Medellin, Colombia, have discovered a graveyard of comets. The researchers, led by Anitoquia astronomer Prof. Ignacio Ferrin, describe how some of these objects, inactive for millions of years, have returned to life leading them to name the group the 'Lazarus comets'.

The new work looked at a third and distinct region of the Solar System, the main belt of asteroids between the orbits of Mars and Jupiter. This volume of space contains more than 1 million objects ranging in size from 1 m to 800 km. The traditional explanation for asteroids is that they are the building blocks of a planet that never formed, as the movement of the pieces was disrupted by the strong gravitational field of Jupiter.

In the last decade 12 active comets have been discovered in the asteroid main belt region. This was something of a surprise and the Medellin team set out to investigate their origin. The team, made up of Prof. Ferrin and his colleagues Profs. Jorge Zuluaga and Pablo Cuartas, now think they have an explanation.

"We found a graveyard of comets," exclaims Professor Ferrín. He adds: "Imagine all these asteroids going around the Sun for aeons, with no hint of activity. We have found that some of these are not dead rocks after all, but are dormant comets that may yet come back to life if the energy that they receive from the Sun increases by a few per cent."

More - Link >>> http://www.sciencedaily.com/releases/2013/08/130802080248.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fspace_time+%28ScienceDaily%3A+Space+%26+Time+News%29

Sources: Royal Astronomical Society (RAS), ScienceDaily.com .

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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://buhlplanetarium.tripod.com/#GAW >
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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 >
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  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
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Astronomical Calendar: 2013 August

Image of America's first professional woman astronomer, Maria Mitchell, whose 195th
birthday is August 1 of 2013. She won a gold medal prize presented by the King of
Denmark, for her discovery of a comet named in her honor: Miss Mitchell's Comet.
(Image Sources: National Oceanic and Atmospheric Administration/ U.S. Department
of Commerce, Wikipedia.org )

Astronomical Calendar for 2013 August:

Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2013.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.


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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://buhlplanetarium.tripod.com/#GAW >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.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 >