Friday, February 23, 2018

Proposed NASA Budget Cuts IR Space Telescope & Phases Out International Space Station



This photograph shows a model of what the Wide-Field Infrared Space Telescope (WFIRST) would look like, if ever constructed. (Image Sources: NASA, Wikipedia.org)

By Glenn A. Walsh
Reporting for SpaceWatchtower

A proposed Wide-Field Infrared Space Telescope would be canceled, and funding for the International Space Station would be phased-out by 2025, in a NASA budget for Fiscal Year 2019 proposed by the Trump Administration. The budget places higher priorities on missions which would take humans back to the Moon, and eventually to Mars.

An Internet link to the entire proposed FY 2019 NASA budget can be found near the end of this blog-post.

This proposal bumps-up NASA funding to $19.9 billion for one year (due to the recently-passed two-year Federal budget compromise), but reduces the budget back to $19.6 billion for future years. NASA Acting Chief Financial Officer Andrew Hunter said the extra $300 million for FY 2019 will be spread across several agency programs: planetary science, construction, exploration research, aiding transition of NASA communications services to commercial satellites, and commercial cargo.

There are other NASA programs slated for elimination by this proposed budget including five Earth-science missions (most related to climate change, including one in collaboration with the National Oceanic and Atmospheric Administration). And, it is proposed that the NASA education office, which for decades has helped the general public, particularly school children, understand the various NASA missions, would also be shuttered.

However the biggest surprise in the budget, and the surprise that has most outraged scientists, is the cancellation of the Wide-Field Infrared Space Telescope (WFIRST). To be launched in the mid-2020s after the launch of the James Webb Space Telescope, the primary mission of WFIRST is to study dark energy, little understood by scientists, which comprises 68.3 per-cent of the energy in the known Universe. Another important mission of WFIRST is the continual search for planets in other solar systems, including a chronograph which should provide the first direct images and spectra of some of these exo-planets.

WFIRST was first proposed in 2010, as the result of an exhaustive study of possible NASA missions conducted every ten years called the Decadal Survey. An expert committee of scientists, organized by the National Academies of Sciences, Engineering, and Medicine, had declared WFIRST as the top priority for a large “flagship” space telescope after the Webb Space Telescope is orbited and operating.

The American Astronomical Society (AAS – the major organization of professional astronomers in North America) has denounced the proposed cancellation of WFIRST saying, "We cannot accept termination of WFIRST, which was the highest-priority space-astronomy mission in the most recent decadal survey." In the statement issued by AAS President-elect Megan Donahue, she also says, "And the proposed 10% reduction in NASA's astrophysics budget, amounting to nearly $1 billion over the next five years, will cripple US astronomy."

In an op-ed column in SpaceNews.com, Jon A. Morse, former Director of NASA's Astrophysics Division (who now heads the non-profit BoldlyGo Institute and is a Research Associate at the Harvard-Smithsonian Center for Astrophysics), said “The long-term picture that the WFIRST cancellation and budget reduction presents for the future of NASA’s astrophysics program is troubling...Despite performing world-class science that captures the imaginations of people around the globe, it is stunning to see that the astrophysics funding is projected to be below its budget from 15 years ago, as though it were a dying field of inquiry with no discoveries left to make. Nothing could be further from the truth!”

Jon Morse concludes the op-ed column by saying, “Congress needs to restore the WFIRST mission to NASA’s portfolio, to avoid the catastrophe of a “lost decade” and atrophying U.S. leadership in some of the world’s most exciting scientific fields.”

The eventual phase-out of Federal funding for the International Space Station (ISS) by 2025 was expected. It is the wish of the Trump Administration to transition the ISS to the private sector by 2025. To aid in this transition to ISS operation by corporate entities, NASA would be funded $150 million in the first year, with the eventual expenditure of $900 million over the next five years for such a commercial transition.

For the return of Americans to the Moon, the budget proposes that a “key power and propulsion space tug” be commercially launched by 2022, as a major part of NASA's Lunar Orbital Platform – Gateway. The proposed budget also includes a new lunar robotic exploration program and an Exploration Research and Technology program to increase technological knowledge needed to sustain human habitation of the Moon and beyond.

While the astrophysics budget is proposed to be cut, the planetary science budget would be increased by $2.2 billion. This includes $50 million to begin planning for a robotic Mars sample return mission, as well as $150 million for planetary defense against wayward asteroids.

Other planetary missions included in the budget are the Mars 2020 Rover mission and “Europa Clipper,” which will investigate Jupiter's icy moon, Europa, which has a large sea below the ice that could include some forms of life.

As with most Presidential proposed budgets, this proposal will undoubtedly be modified by the U.S. Congress before being formally enacted. Already, some members of Congress are condemning the proposed budget cuts to NASA programs.

Senator Bill Nelson (D-FL), ranking member of the Senate Commerce, Science, and Transportation Committee, said in a statement, “The administration’s budget for NASA is a nonstarter. If we’re ever going to get to Mars with humans on board and return them safely, then we need a larger funding increase for NASA.” Senator Nelson was the second sitting member of Congress to fly in space, as a Payload Specialist aboard the Space Shuttle Columbia, launched on 1986 January 12 (this was the last successful Space Shuttle mission before the tragic loss of the Space Shuttle Challenger on 1986 January 28).

Senator Nelson also said, regarding the ending of Federal funding for the ISS, “Turning off the lights and walking away from our sole outpost in space at a time when we’re pushing the frontiers of exploration makes no sense.”

Criticism by U.S. Rep. Eddie Bernice Johnson (D-TX), ranking Democrat on the House Science, Space, and Technology Committee, went beyond the cuts to NASA: “When I was first briefed on ‘highlights’ of President Trump’s budget request, I was incredulous at its treatment of our federal science agencies. To propose slashing EPA’s budget and DOE’s EERE, eliminating NASA’s education programs and several Earth science instruments and missions, and cutting NOAA’s oceans and atmospheric programs, just to name a few of the damaging proposals in this document, shows that this Administration has no appreciation for the role that these agencies play in driving the economy, keeping our nation competitive, and protecting the environment and public health. The only good thing about this budget is that it’s so extreme, I have no doubt that it will be summarily rejected by both sides of the aisle.”

Internet Links to Additional Information ---

Wide-Field Infrared Space Telescope (WFIRST):
Link >>> https://en.wikipedia.org/wiki/Wide_Field_Infrared_Survey_Telescope

Trump Administration FY 2019 Budget Request for NASA:
Link >>> https://www.nasa.gov/sites/default/files/atoms/files/fy19_nasa_budget_estimates.pdf

Information Regarding Budget of NASA:
Link >>> https://en.wikipedia.org/wiki/Budget_of_NASA

Related Blog Post ---

"NASA & the Trump Administration." 2017 Jan. 23.

Link >>> http://spacewatchtower.blogspot.com/2017/01/nasa-trump-administration.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2018 February 23.

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Duquesne Incline cable-car railway, Pittsburgh:
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Tuesday, February 6, 2018

Web-Cast: 1st Test Launch of SpaceX Falcon Heavy Rocket Tue. Afternoon

                            Falcon Heavy cropped.jpg
The SpaceX Falcon Heavy Launch Rocket on launch pad LC-39A (Launch Complex 39A) at the John F. Kennedy Space Center, Cape Canaveral, Florida.
(Image Sources: Wikipedia.com, By SpaceX - This file has been extracted from another file: Falcon Heavy Demo Mission (38583829295).jpg, CC0, https://commons.wikimedia.org/w/index.php?curid=65217917)

By Glenn A. Walsh
Reporting for SpaceWatchtower

UPDATE 2: Launch is now scheduled no earlier than 3:45 p.m. EST / 20:45 UTC, Tuesday, 2018 February 6, due to wind shear in the upper level of the atmosphere.

UPDATE: Launch is now scheduled no earlier than 3:05 p.m. EST / 20:05 UTC, Tuesday, 2018 February 6.

The pioneering private space firm, SpaceX, plans the first test launch of its heavy-lift rocket, called Falcon Heavy, this afternoon (Tuesday, 2018 February 6), with a 3-hour launch window opening at 1:30 p.m. Eastern Standard Time (EST) / 18:30 Coordinated Universal Time (UTC). At the end of this blog-post are Internet links to the live, Internet Web-Cast stream from SpaceX of the launch of the Falcon Heavy.

The Falcon Heavy Rocket will lift-off from launch pad LC-39A at the John F. Kennedy Space Center in Cape Canaveral, Florida. Launch pad LC-39A (Launch Complex 39-A) was the site of the Apollo spacecraft launches to the Moon, as well as the launches during the Space Shuttle program.

The Falcon Heavy Rocket is a modification of the SpaceX Falcon 9 launch vehicle, plus two first-stage Falcon 9 rockets as strap-on boosters. With the Falcon Heavy, SpaceX expects to be able to launch much heavier payloads into orbit and into Deep-Space.

For low Earth orbit (LEO), the Falcon Heavy will be able to lift payloads up to 140,700 pounds / 63,800 kilograms. The SpaceX Falcon 9 Rocket (with full-thrust) can only lift payloads up to 50,300 pounds / 22,800 kilograms.

For launching into geostationary or geosynchronous orbit, the Falcon Heavy (with first-stage and side booster recovery) can lift up to 17,637 pounds / 8,000 kilograms. For a recoverable Falcon 9 Rocket, the maximum lift is 12,100 pounds / 5,500 kilograms. Satellites launched into geostationary or geosynchronous orbit are often communications, navigation (i.e. GPS), or weather probes, which need to appear to remain above one particular portion of the Earth.

The Falcon Heavy Rocket is designed for future crewed missions, as well as lifting heavy payloads. Last year, SpaceX announced that two unnamed passengers would fly in a SpaceX Dragon Capsule, launched by a Falcon Heavy, for a trip around the Moon and back to Earth sometime in 2018.

For this test launch, the payload selected by SpaceX Founder and Chief Executive Officer Elon Musk will be none-other than a cherry-red Tesla Roadster. The electric automobile company, Tesla, was also founded by Elon Musk!

In Instagram social media posts yesterday, Elon Musk shows a “passenger” may be aboard the Tesla Roadster during the Falcon Heavy launch. “Starman in a Red Roadster,” a dummy in an official SpaceX spacesuit, is shown suited-up, buckled-in and ready for launch!

The plan is not to have this Tesla Roadster simply reach Earth orbit. SpaceX plans for this payload to go into a highly elliptical orbit around the Sun. And, it seems, the cherry-red color of the Tesla Roadster is no accident. From time-to-time, this Tesla Roadster will come close to the Red Planet, Mars!

Elon Musk has publicly stated his interest in sending a rocket, and eventually people, to Mars. SpaceX has already begun development of a successor to the Falcon Heavy, known as the BFR Rocket, for long-duration space flights.

Ever the optimist, Elon Musk had originally planned the first test flight of the Falcon Heavy in 2013, when he announced development of the launch vehicle in 2011. However, despite taking longer to develop, today's launch will be a milestone for the private rocket launch industry. The Falcon Heavy will be the most powerful American rocket built since the famed Saturn V Rocket, which took men to the Moon in the late 1960s and early 1970s.

In the 1980s, NASA had hoped that the Space Shuttle would lower the cost of transportation to space, eventually making such transit routine. However, despite the idea of reusing Space Shuttle vehicles, after they glided to a landing on an extended airport-type runway, the cost of Space Shuttle missions were never brought down to a reasonable cost.

SpaceX, which has pioneered reusing much of their flight equipment, has significantly brought down the cost of Falcon Heavy launches to $90 million. This compares to the launch cost of the most powerful rocket operating today, United Launch Alliance's Delta IV Heavy, which costs between $300 million and $500 million.

One of the major reasons SpaceX can have such a low-cost access to Outer Space is because the company tries to reuse nearly everything in a space launch. For instance, in this test launch, SpaceX will attempt to land all three of the Falcon Heavy's first-stage core boosters, for reuse on future launches. If this is successful, this will be yet another amazing accomplishment for SpaceX.

Amazon.com Founder Jeff Bezos, who has also founded a private space company known as Blue Origin, is also developing a heavy-lift rocket called New Glenn. And, of course, NASA continues developing the Space Launch System (SLS), including a heavy-lift rocket, for crewed missions to the Moon and Mars. Test flights of both New Glenn and SLS are expected in 2020.

Internet Links to Live, Web-Cast Stream of Falcon Heavy Test Launch, Tuesday, 2018 February 6 (3-hour launch window opens at 1:30 p.m. EST / 18:30 UTC):
Link 1 >>> http://www.spacex.com/webcast
Link 2 >>> https://www.space.com/17933-nasa-television-webcasts-live-space-tv.html

Internet Links to Additional Information ---

SpaceX Falcon Heavy Rocket: Link >>> https://en.wikipedia.org/wiki/Falcon_Heavy

SpaceX BFR Rocket: Link >>> https://en.wikipedia.org/wiki/BFR_(rocket)

Photos: SpaceX Falcon Heavy Readies for Launch:
Link >>> https://www.space.com/39279-spacex-first-falcon-heavy-rocket-photos.html

Related Blog-Posts ---

"Winter & SpaceX Launch w/ Web-Cast Tonight; Ursid Meteors Peak Dec. 22."

2015 Dec. 21.

Link >>> http://spacewatchtower.blogspot.com/2015/12/winter-spacex-launch-w-web-cast-tonight.html 

 

"NASA Orders SpaceX Astronaut Launches." 2015 Nov. 22.

Link >>> http://spacewatchtower.blogspot.com/2015/11/nasa-orders-spacex-astronaut-launches.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2018 February 6.

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& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
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South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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:
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* Civil War Museum of Andrew Carnegie Free Library:
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Duquesne Incline cable-car railway, Pittsburgh:
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* Public Transit:
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Thursday, February 1, 2018

Astronomical Calendar: 2018 February


Last month, SpaceWatchtower said: "January could be called the month of the Moon!" See why:
Link >>> http://spacewatchtower.blogspot.com/2018/01/astronomical-calendar-2018-january.html
Well, 2018 February is the month with NO Full Moon phase! With only 28 days in the month of February, and with both January and March having a "Blue Moon," this does not allow any Full Moon to fall within 2018 February.
(Image Sources: Wikipedia.org , By Tomruen - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=53147136 )

Astronomical Calendar for 2018 February: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2018.html#feb

 Related Blog Post ---


"Astronomical Calendar: 2018 January." 2018 Jan. 2.

Link >>> http://spacewatchtower.blogspot.com/2018/01/astronomical-calendar-2018-january.html


Source: Friends of the Zeiss.
              2018 February 1.

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Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
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South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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, January 27, 2018

Lasers to Clear-Away Space Junk?

                                                                      
This graphic shows how a ground-based laser system may be able to clear-away space junk by de-orbiting the particles.
(Graphic Source: Wired Magazine < https://www.wired.com/2011/10/space-junk-laser/ >)

By Glenn A. Walsh
Reporting for SpaceWatchtower

Can lasers be used to clear-away space junk? For more than 20 years, scientists have been considering using ground-based lasers to solve an increasing problem for satellites and other spacecraft in Earth orbit. Now, the Chinese are proposing to use space-based lasers to solve the problem.

No, we are not talking about completely incinerating space junk with laser beams, as phaser beams on the popular science-fiction television and motion picture series, Star Trek, are often seen to incinerate targets. The idea is to affect the orbit of the particular piece of space junk, so the heating of the object by a laser beam either moves the object to an orbit that does not threaten operating satellites, moves it to an orbit where it will eventually de-orbit and burn-up in the atmosphere, or both. Some people refer to such a ground-based laser system as a “Laser Broom.”

Space junk or space debris has been in orbit, just above Earth's atmosphere, since the dawn of the Space Age in 1957, when Russia orbited the first artificial satellites, Sputnik 1 & 2. This was followed soon-after by the first American satellite, Explorer 1. Wednesday marks the 60th anniversary of the launch of Explorer 1.

Since then, the United States, Russia, and China have sent both crewed and uncrewed spacecraft into Earth orbit. Thirteen other nations and the European Union have also sent uncrewed satellites into orbit. And, more recently, private firms such as SpaceX have started sending uncrewed spacecraft into orbit, with the prospect of sending crewed spacecraft in the not-too-distant future.

After more than 60 years, many obsolete and unused satellites, as well as spent rocket boosters and other auxiliary apparatus, remain in orbit. And, through collisions of some of these objects, small and even more dangerous artificial space particles now exist in orbit.

February of 2009 saw the first collision between an active satellite (Iridium satellite-telephone communications satellite) and a defunct satellite (Russian Cosmos weather satellite). Such collisions were predicted in 1978 by NASA scientist Donald Kessler, and hence this new phenomena is known as the Kessler Syndrome.

The cluttering of orbits with such particles from space collisions was predicted, by the Kessler Syndrome, to eventually make certain orbits quite unsafe for new satellites, and hence, unusable by space-faring nations. The danger is that much of this space junk travels at speeds of nearly 17,000 miles per hour or 7.5 kilometers per second.

Tiny particles, such as even a flake of paint, from some previous space missions, traveling at those kind of speeds, can be hazardous to satellites, the International Space Station (ISS), and particularly to someone outside a spacecraft conducting an extra-vehicular activity (EVA - ie. a space-walk). The ISS is clad in special shielding to protect the orbital laboratory from small impacts often received from orbiting space debris. And, to avoid the larger orbiting particles, sometimes the Space Station is moved out-of-the-way.

Even in low Earth orbit, much of this space junk could remain in orbit for years or even centuries. In geo-synchronous orbit (approx. 22,236 statute miles / 35,786 kilometers above the Earth; an orbit that mimics the rotation rate of the Earth), space junk could remain in orbit indefinitely, as there is minimal friction to create drag and slow the space junk. Many communications satellites are placed in geo-synchronous orbits, so they appear to stay above one part of the Earth at all times.

In 1996, NASA and the U.S. Air Force, in a study titled Project ORION, suggested using ground-based lasers to nudge space junk out-of-the-way or toward de-orbiting. These would be very powerful lasers (5 kilowatts in power, costing around $800,000 a piece), which would vaporize surface material on target space debris, to drive it toward the atmosphere where it would burn-up.

Scientists noted that such a system could also be used to move active satellites into more advantageous orbits. This would reduce the need for such satellites to be launched with additional rocket propellent, saving weight and money

Such a laser system, including operating system and telescope, would cost in the tens of millions of dollars. Scientists believe such a system could engage about 10 pieces of space junk per day. However, such powerful lasers could be seen as a threat to orbiting spacecraft of other nations.

In 2015, a team of scientists from Japan's RIKEN research lab proposed sending a laser cannon to the ISS, to clear-away space junk in low Earth orbit. Mounted on the ISS, the project would begin with a much weaker laser, about 10 watts of power firing 100 laser pulses a second. Eventually, according to the researchers, a dedicated space junk-cleaning satellite could house a 500,000-watt laser, which could pulse 50,000 times per second. Again, a major obstacle to this proposal is the fear that this space-based laser cannon could have military applications.

In a scientific research paper issued this month, Chinese researchers are also proposing a powerful space-based laser to clean-up space junk. The paper titled, “Impacts of orbital elements of space-based laser station on small scale space debris removal” published in the February issue of Optik – International Journal for Light and Electron Optics, was produced by scientists at the Chinese Air Force Engineering University.

It is, perhaps, appropriate that China concentrate on the removal of space debris. China created a great deal of space debris in 2007, with an anti-satellite missile test on an old Chinese satellite. This one test created thousands of new pieces of junk in low Earth orbit, the most severe fragmentation in the history of space debris. One fragment seems to have damaged a Russian spacecraft in 2013.

However, there is great skepticism as to whether space junk is all China is interested in, regarding space-based lasers. A U.S. Congressional commission, the U.S.-China Economic Security and Review Commission, reported last year that China is very interested in shooting-down U.S. satellites.

Internet Links to Additional Information ---

Laser: Link >>> https://en.wikipedia.org/wiki/Laser

Space Junk or Space Debris: Link >>> https://en.wikipedia.org/wiki/Space_debris

Laser Broom: Link >>> https://en.wikipedia.org/wiki/Laser_broom

Daley, Jason. "Amateur Astronomer Finds Long-Lost NASA Satellite." 

Smithsonian Magazine 2018 Jan. 29.


Palmer, David. "Satellite 'License Plates' Could Prevent a Disaster in Low Earth Orbit."
Blog: The Crux.
Discover Magazine 2017 Dec. 18.
Link >>> http://blogs.discovermagazine.com/crux/2017/12/18/satellite-license-plates/#.Wm7cHnlG3IV

Related Blog Posts ---

"New USAF 'Space Fence' to Track Space Junk by 2019." 2014 May 10.

Link >>> http://spacewatchtower.blogspot.com/2014/05/new-usaf-space-fence-to-track-space.html

 

"Sequestration: Cuts to USAF 'Space Fence' Tracking Space Junk ?" 2013 April 16.

Link >>> http://spacewatchtower.blogspot.com/2013/04/sequestration-cuts-to-usaf-space-fence.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2018 January 27.

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                Want to receive SpaceWatchtower blog posts in your in-box ?
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gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
TransportWatchtower Blog: < http://transportwatchtower.blogspot.com  >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >

Monday, January 8, 2018

100 Years Ago: Shapley Discovers True Magnitude of Milky Way & True Location of Earth in Galaxy



                                                  HarlowShapely-crop.jpeg
Photograph of astronomer Harlow Shapley, who discovered a century ago that the Milky Way Galaxy was much larger than previously thought, and that Earth and our Solar System are not at the center of the Galaxy. (Image Source: Wikipedia.org )
Near the end of this blog-post is a photograph showing Harlow Shapley at the ceremony, where he delivered the keynote address, for the dedication of a rather unique 10-inch Siderostat-Type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.

By Glenn A. Walsh
Reporting for SpaceWatchtower

As we move further into the 21st century, often people do not realize that it was only a century ago that we began to understand how large our Milky Way Galaxy really is, and our true place in the Galaxy.

Today, 100 years ago (on 1918 January 8), astronomer Harlow Shapley wrote a letter to British astronomer Arthur Eddington announcing a new breakthrough regarding the Universe's “galactic system.” In part, he wrote to Dr. Eddington:

To be brief, the globular clusters outline the sidereal system, but they avoid the plane of the Milky Way...All of our naked-eye stars, the irregular nebulae, eclipsing binaries—everything we know about, in fact, and call remote, [belong to this system] except those compactly formed globular clusters, a few outlying cluster-type variables, the Magellanic Clouds, and perhaps, the spiral nebulae. The globular clusters apparently can form and exist only in the parts of the universe where the star material is less dense and the gravitational forces less powerful than along the galactic plane. This view of the general system, I am afraid, will necessitate alterations in our ideas of star distribution and density in the galactic system.

Harlow Shapley studied bright globular star clusters, instead of individual stars. These globular clusters were outside of our Galaxy's true center, where cosmic dust blocks light from some stars (this cosmic dust had previously convinced astronomers that we were near the center of the Galaxy). The globular clusters studied were quite bright, even at large distances. After measuring the distances to many globular clusters, he was able to use them to find the true center of the Milky Way.

By observing and analyzing Cepheid and other variable stars, particularly RR Lyrae stars, he had concluded that the Milky Way Galaxy was much larger than astronomers of the time had believed. Now believing that our Galaxy was about 300,000 light-years in diameter, Dr. Shapley was correct that it was much larger than previously thought, but he also over-estimated the size..

And, while most scientists of the time assumed that our Solar System was in, or near, the center of the Milky Way Galaxy, Dr. Shapley also concluded, using parallax observations, that our Solar System was actually no-where near the center and actually toward one side of the Galaxy.

At the time Dr. Shapley was working for astronomer George Ellery Hale, using the 60-inch reflector telescope at Mount Wilson Observatory near Pasadena, California. The world's largest operating telescope at that time, the lens blank had been funded by Dr. Hale's father, William Hale, while the rest of the observatory was funded by industrialist and philanthropist Andrew Carnegie through his Carnegie Institution of Washington. Dr. Shapley went on to become Director of the Harvard College Observatory in 1921, remaining Director until 1952.

Harlow Shapley published a series of 14 scientific papers, between 1915 and 1919, detailing his research and conclusions. Scientists immediately read and started debating his results. Although American astronomer Henry Norris Russell wrote an article in Scientific American magazine, where he described Dr. Shapley's results as “simply amazing,” the general public did not become aware of the “great enlargement” of the Milky Way Galaxy until much later. Due to World War I and the War's aftermath, the first news article on the subject only appeared on the front page of The New York Times on 1921 May 31, along with a front page article in the Chicago Daily Tribune.

Although Harlow Shapley revolutionized our view of the Milky Way Galaxy, and the location of our Solar System in the Galaxy, his views were still very controversial among scientists, and he believed some things that have since been proven incorrect. While he had concluded that the Milky Way Galaxy was 300,000 light-years in diameter, we now know that our Galaxy is between 100,000 and 180,000 light-years in diameter.

Because he thought the Milky Way was so large, he also concluded that the Milky Way was most if not all of the Universe. For several scientific reasons, he thought that, what we know now as the Andromeda Galaxy as well as other spiral nebulae, could not be large and outside of our Galaxy.

Consequently, a Great Debate on the nature of the Universe and the possible existence of other galaxies was held between Dr. Shapley and Heber D. Curtis, Director of the Allegheny Observatory in Pittsburgh. This Great Debate was held before the U.S. National Academy of Sciences in Washington, DC on 1920 April 26.

Science author and retired college Astronomy professor Thomas William Hamilton writes, "What is generally overlooked, thanks to Shapley's own PR efforts, is that in the great debate between Harlow Shapley and Heber Curtis each was half right and half wrong, as Curtis persisted in the view we were near the center of our galaxy, but argued there are many other galaxies; while Shapley deduced we are on the outskirts, but believed ours was the only galaxy."

Although both astronomers presented convincing evidence for their positions (later, some of this evidence was verified by other scientists), regarding the main dispute of whether other galaxies existed, Dr. Curtis has been proven correct. (A link to additional information about this Great Debate near the end of this blog-post.)

Over the years, Harlow Shapley delivered many academic lectures. On Wednesday Evening, 1941 November 19, he delivered the keynote address at the dedication of a rather unique 10-inch Siderostat-Type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science (a link to more information about this telescope near the end of this blog-post).

Harlow Shapley had a close relationship with Buhl Planetarium. Leo Scanlon, co-founder of the Amateur Astronomers Association of Pittsburgh in 1929, builder of the world's first all-aluminum observatory dome in 1930, and one of the first Buhl Planetarium lecturers in 1939, had worked with Dr. Shapley as early as 1934. After Mr. Scanlon presented a paper titled, "The Efficiency of Amateur Variable Star Observers," before the 1934 convention of the American Association of Variable Star Observers (AAVSO) at the Franklin Institute in Philadelphia, Dr. Shapley facetiously suggested that Mr. Scanlon should read the same paper to Dr. Shapley's sometimes sloppy staff at Harvard!

Harlow Shapley was a great supporter of Amateur Astronomy. Although delayed by the United States entry into World War II, a nation-wide organization of amateur astronomers, called the Astronomical League, was finally established on 1947 July 4. Dr. Shapley served as Interim President at the founding convention at Philadelphia's Franklin Institute (a preliminary planning meeting, in 1940, had occurred at Buhl Planetarium). (A link to additional information regarding the creation of the Astronomical League near the end of this blog-post.)

Harlow Shapley served on the Board of Trustees of Science Service from 1935 to 1971 and was elected President of the American Association for the Advancement of Science in 1947.

Today (2018 January 8) also marks the 150th anniversary of the birth of English astronomer Frank Watson Dyson, who became Director of the Royal Greenwich Observatory (England's Astronomer Royal) in 1910 and remained Director for 23 years. Dr. Dyson also studied the structure of the Milky Way and the Sun.

Frank Watson Dyson organized two historic expeditions to study the Total Eclipse of the Sun in 1919. He specifically proposed using observations from this eclipse to confirm predictions made by Albert Einstein, in Dr. Einstein's 1915 General Theory of Relativity. Observations of a slight shift in star positions near the Sun, during the eclipse, confirmed the theory's predictions, immediately making Albert Einstein world famous.

In the 1920s, Frank Watson Dyson started using the new technology of radio to transmit precise time signals of Greenwich Mean Time (the recognized international time scale used by most scientists, now known as Coordinated Universal Time) every quarter-hour on a radio station operated by the British Post Office. In 1924, he arranged for the British Broadcasting Corporation to transmit these precise time signals as “six pips” at the beginning of each hour. Back in 1868, Pittsburgh's Allegheny Observatory had provided railroads and cities precise time signals via the telegraph.

Special Thanks: Marilyn E. Morgan, Mount Wilson Observatory.

The following two news articles, with two photographs, come from the Pittsburgh Post-Gazette on Thursday Morning, 1941 November 20. The previous evening, Harvard College Observatory Director Harlow Shapley (third from left, in the left photograph) delivered the keynote address at the dedication of a rather unique 10-inch Siderostat-Type Refractor Telescope, at Pittsburgh's original Buhl Planetarium and Institute of Popular Science. Also pictured in this photograph are (left to right) William H. Barton, Director of New York City's Hayden Planetarium, Buhl Planetarium Director Arthur Draper, and Mrs. Nicholas E. Wagman (whose husband, at that time, was Director of Pittsburgh's Allegheny Observatory). (Sources: Pittsburgh Post-Gazette, Friends of the Zeiss)

http://buhlplanetarium3.tripod.com/Buhlscrapbook-Siderostat2.JPG

Book Chapter Citation ---

Bartusiak, Marcia. The Day We Found the Universe. New York: Pantheon Books, 2009. 114-134. Print.

Internet Links to Additional Information ---

Harlow Shapley -
Link 1 >>> http://www.encyclopedia.com/people/science-and-technology/astronomy-biographies/harlow-shapley
Link 2 >>> https://en.wikipedia.org/wiki/Harlow_Shapley

The 1920 Great Debate on the Scale of the Universe - Between Harlow Shapley and Heber D. Curtis, Director of Pittsburgh's Allegheny Observatory:
Link >>> http://buhlplanetarium2.tripod.com/bio/greatdebate.html

Harlow Shapley and Buhl Planetarium Assist in Creation of The Astronomical League:
Link >>> http://buhlplanetarium4.tripod.com/AstroLeague.html

10-inch Siderostat-Type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science:
Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html

History of Andrew Carnegie and Carnegie Libraries:
Link >>> http://www.andrewcarnegie.cc

Frank Watson Dyson ---

Related Blog Posts ---

"Centennial: Mt. Wilson Observatory's 100-inch Hooker Telescope." 2017 Nov. 3.

 Link >>> http://spacewatchtower.blogspot.com/2017/11/centennial-mt-wilson-observatorys-100.html


Centennial: Einstein's General Theory of Relativity." 2015 Nov. 25.

Link >>> http://spacewatchtower.blogspot.com/2015/11/centennial-einsteins-general-theory-of.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2018 January 8.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
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                Want to receive SpaceWatchtower blog posts in your in-box ?
                Send request to < spacewatchtower@planetarium.cc >.

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
TransportWatchtower Blog: < http://transportwatchtower.blogspot.com  >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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, January 2, 2018

Astronomical Calendar: 2018 January


January could be called the month of the Moon! Two Full Moons occur in January, January 1 and 
January 31. The Full Moon of January 1 is the closest to Earth, and largest in appearance, for 2018, 
due to close proximity to Lunar Perigee (which can lead to large tides along ocean coastlines), which some people refer to as a "Super-Moon." A second "Super-Moon" occurs on January 31 for the second Full Moon in a calendar month, known as a "Blue Moon." And, the January 31 Full Moon occurs at the time of a Total Lunar Eclipse visible over most of the Earth except most of South America, most of Africa, Western Europe, and Antarctica. An Eclipse of the Moon / Lunar Eclipse is the type of eclipse completely safe to watch with telescopes, binoculars, and the naked-eyes.
(Image Sources: Wikipedia.org , By Tomruen - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=53147136 )

Astronomical Calendar for 2018 January: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2018.html#jan

 Related Blog Post ---


"Astronomical Calendar: 2017 December." 2017 Dec. 1.

Link >>> http://spacewatchtower.blogspot.com/2017/12/astronomical-calendar-2017-december.html


Source: Friends of the Zeiss.
              2018 January 2.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
TransportWatchtower Blog: < http://transportwatchtower.blogspot.com  >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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, December 21, 2017

Winter Begins; Ursid Meteors Peak Friday

http://buhlplanetarium.tripod.com/pix/graphics/solsticeimage008.png
This diagram shows the position of the Earth, in relation to the Sun, at the time of the Winter Solstice, as well as the other solstice and equinoxes of the year, in Earth's Northern Hemisphere.
(Graphic Source: ©1999, Eric G. Canali, former Floor Manager of Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Founder of the South Hills Backyard Astronomers amateur astronomy club; permission granted for only non-profit use with credit to author.)

By Glenn A. Walsh
Reporting for SpaceWatchtower

The season of Winter, in the Northern Hemisphere of Earth, begins at the moment of the Winter / December Solstice, Thursday, 2017 December 21 at 11:28 a.m. Eastern Standard Time (EST) / 16:28 Coordinated Universal Time (UTC)---the moment of the posting of this blog-post. This moment also marks the astronomical beginning of the Summer season in the Southern Hemisphere.

Almost 24 hours later, Friday morning will mark the peak time for the annual Ursid Meteor Shower; of course dark skies are needed to actually see meteors. This meteor shower peaks Friday, 2017 December 22 at 10:00 a.m. EST / 15:00 UTC.

                                               Winter Solstice 2017

In etymology, the word solstice comes from the Latin terms sol (Sun) and sistere (to stand-still). In ancient times, astronomers / astrologers / priests recognized that one day of the year when the Sun would appear to reach its lowest point in the sky for the entire year. The motion of the Sun's apparent path in the sky (what is known astronomically today as the Sun's declination) would cease on this day, and the Sun would appear to stand-still, before reversing direction.

With our Gregorian Calendar, this usually occurs on, or very close to, December 21. In ancient times, when people used the Julian Calendar, the Winter Solstice was on, or very close to, December 25, what we now know as Christmas Day. Mid-Winter festivals, at the time of the Winter Solstice, were common in ancient times. Instead of competing with these traditions, the early Roman Catholic Church Christianized the Winter festivals by observing the birth of Jesus Christ on December 25 (the actual birth date of Jesus was probably in September).

Today, we know that, while the Sun does have motions, it is actually the motion of the Earth, tilted on its axis 23.44 degrees from the plane of our Solar System while revolving around the Sun, that causes the Earth's seasons. Hence, as the Earth arrives at the point in its orbit around the Sun, where the south polar axis is most directly inclined toward the Sun (thus, the Sun appears at its lowest point for the year in the Northern Hemisphere sky) around December 21, this marks the Winter Solstice in the Northern Hemisphere (and the Summer Solstice in the Southern Hemisphere).

Alternately around June 21, the Summer Solstice marks the beginning of Summer in the Northern Hemisphere (and this date also marks the Winter Solstice, which is the beginning of Winter in the Southern Hemisphere) as the Earth reaches the point in its orbit where the north polar axis is most directly inclined toward the Sun.

The day of the December Solstice is the only time of the year when the Sun reaches the point of Local Solar Noon at the South Pole. Conversely, it is also the only time of the year when Local Solar Midnight occurs at the North Pole. And, of course, it is the reverse during the June Solstice: the only time the Sun reaches the point of Local Solar Noon at the North Pole and the only time when Local Solar Midnight occurs at the South Pole.

Although the Winter months in the Northern Hemisphere are known for the year's coldest weather, the Earth is actually at the point in its orbit closest to the Sun (astronomically known as the point of perihelion) on or very near January 2. The Earth is farthest from the Sun, each year shortly after the Northern Hemisphere's Summer Solstice, on or very near July 5 (the point of aphelion).

Solar radiation, and hence heat from the Sun, to warm an Earth hemisphere depends on the length of daylight and the angle of the Sun above the horizon. The tilt of the planet's axis toward the Sun determines the additional and more direct solar radiation received by a planet's northern or southern hemisphere, and hence, the warmer season of the respective hemisphere.

The Earth's perihelion in January and aphelion in July is due to the elliptical nature of the Earth's orbit around the Sun. Perihelion and aphelion would not occur if the Earth's orbit was a true circle.

Since the Earth is closest to the Sun near the beginning of the Northern Hemisphere's Winter Season, the Earth, then, moves faster in its orbit around the Sun than it moves in July, making the Northern Hemisphere's Winter a shorter season than Summer. Winter will last for only 89 days, while this past-Summer lasted nearly 93 days. This is one of the observed consequences of Johannes Kepler's Laws of Planetary Motion, which he published at the beginning of the 17th century.

The day of the Winter Solstice is known as the “shortest day of the year” and the “longest night of the year” as the Sun shines on the Northern Hemisphere for the shortest length of time for the entire year, on this day. For this reason, Homeless Persons' Memorial Day is commemorated on December 21.

Interestingly, the climate of a locale in the Southern Hemisphere is, on average, slightly milder than a location at the same latitude in the Northern Hemisphere, because the Southern Hemisphere has significantly more ocean water and much less land. Water warms-up and cools-down more slowly than does land. The only exception is the Antarctic, which is colder than the Northern Hemisphere's Arctic region, possibly because most of the Arctic region is covered with water (although, often frozen water on the surface, but liquid water beneath the ice) while Antarctica is mostly a land mass.

                                              Ursid Meteor Shower

Almost 24 hours after the Winter Solstice comes the peak of the annual Ursid Meteor Shower, which actually begins on December 17 and usually lasts about a week ending December 24, 25, or 26. The Ursids seem to comprise a narrow stream of debris originating from Comet Tuttle. Hence, it is difficult to see Ursid meteors outside of a 12-hour window before and after the peak, where possibly 12 meteors per-hour could be seen, under ideal conditions.

The Ursid Meteor Shower is so-named because most meteors appear to radiate from a point near the Star Beta Ursae Minoris (apparent meteor shower radiant) in the Constellation Ursa Minor (better known as the asterism the “Little Dipper”), which is the brightest star in the bowl of the Little Dipper. Some people call these meteors “Ursids,” in an attempt to emphasize that their apparent radiant is Ursa Minor, not Ursa Major (the asterism the “Big Dipper”).

However, you should not, necessarily, be looking only at the Little Dipper when looking for meteors in this shower. Meteors can appear in any part of the sky at any time (although a meteor's tail may tend to point back toward the radiant).

Of course meteor showers, like all celestial observations, are weather-permitting. If there are more than a few clouds in the sky, meteors will be much more difficult to find. Clear skies are not always available in the skies of late Autumn and early Winter. And, it is always best to get away from city lights, for the opportunity to see the smaller, dimmer meteors. As always, the best time to view any meteor shower is between local midnight and local dawn, when the Earth is actually rotating into the stream of meteoric debris.

Binoculars and telescopes are not very useful for finding meteors. Meteors streak across the sky in a very short period of time, far too short to aim binoculars or a telescope. So, the best way to view a meteor shower is to lie on a blanket or beach towel on the ground, or use a reclining a chair, outdoors 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.

So, if you go out to see the Ursid Meteor Shower, start looking for meteors around local midnight, or perhaps a little later. Make sure you have a good site where you can see most of the sky, and that sky is relatively clear. Be sure to dress properly for the early morning temperatures, now that we are at the very beginning of Winter.

And, you want to go out ahead of time, before you actually start looking for meteors, to get your eyes accustomed to the dark sky. Dark-adapting your eyes for meteor-watching could take up to a half-hour.

Special Thanks: Eric G. Canali, former Floor Manager of Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Founder of the South Hills Backyard Astronomers amateur astronomy club.

Internet Links to Additional Information ---

More on the Winter Solstice:
Link 1 >>> http://scienceworld.wolfram.com/astronomy/WinterSolstice.html
Link 2 >>> http://en.wikipedia.org/wiki/Winter

More on a Solstice: Link >>> http://en.wikipedia.org/wiki/Solstice

Popular Winter Planetarium Sky Shows Shown at Pittsburgh's original Buhl Planetarium and Institute of Popular Science (1939 to 1991), including full scripts of each show:
The Star of Bethlehem >>> http://buhlplanetarium3.tripod.com/skyshow/bethlehem/
The Stars of Winter >>> http://buhlplanetarium3.tripod.com/skyshow/winter/

More on calendars ---
       Gregorian Calendar: Link >>> http://en.wikipedia.org/wiki/Gregorian_calendar
       Julian Calendar: Link >>> http://en.wikipedia.org/wiki/Julian_calendar

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

More on the Homeless Persons' Memorial Day:
Link >>> http://nationalhomeless.org/about-us/projects/memorial-day/

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2017 December 21.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
TransportWatchtower Blog: < http://transportwatchtower.blogspot.com  >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >