Monday, August 10, 2020

Annual Perseid Meteor Shower Peaks Tue. Night / Early Wed. Morning

    
A short, cropped video-clip of a Perseids meteoroid (at the bright head of the "shooting-star" trail) entering the Earth's atmosphere in slow-motion (x0.1). The meteoroid measured about 0.39-inch / 10 milimeters. This video, aimed at the Constellation Camelopardalis, was taken from Berlin on 2019 August 14.
(Image Sources: Wikipedia.org, By Bautsch - Own work, CC0, https://commons.wikimedia.org/w/index.php?curid=81371519)

By Glenn A. Walsh
Reporting for SpaceWatchtower

This year's Perseid Meteor Shower, which peaks Tuesday evening / early Wednesday morning, is considered the best meteor shower of the year. And, this peak could stretch into Wednesday evening / early Thursday morning.

The peak of the Perseid Meteor Shower, this year, actually occurs Wednesday Morning, 2020 August 12 at 9:00 a.m. Eastern Daylight Saving Time (EDT) / 13:00 Coordinated Universal Time (UTC). However, the best time to watch most meteor showers, including this year's Perseids, is always between local midnight and dawn, when the Earth is rotating into the meteor shower.

At the peak time, sometimes up-to 50-to-100 meteors could possibly be seen per-hour, if observing conditions are ideal. Depending on your location, weather conditions, and the condition of your eye-sight, seeing 50-to-60 meteors per-hour would be more likely.

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. Dark-adapting your eyes for meteor watching could take up-to one half-hour.

For the Perseid Meteor Shower at this time, the Moon will be in a Waning Crescent Phase, having just passed the primary lunar phase of Last Quarter the previous day (Tuesday, 2020 August 11) at 12:45 p.m. EDT / 16:45 UTC. Although the Moon will be visible for most of the early Wednesday morning hours, there should not be quite as much reflected sunlight from the Moon to obscure the dimmer meteors. Try not to look directly at the Moon, so it does not hinder your dark-adapted eye-sight.

Actually, some meteors from the Perseid Meteor Shower can be seen as early as mid-July and as late as late August (~July 17 to August 24); but they are few and far between. Most Perseid meteors can be seen three-to-five days before and three-to-five days after the peak time, which is considered, approximately, between August 9 and 14 each year.

Viewers in the Northern Hemisphere are fortunate that the Perseid Meteor Shower arrives during the Summer month of August, when temperatures are comfortable for night-time viewing. However, some locations (such as in the mountains) could be cooler in the early-morning hours. So, be sure to check your local weather forecast (with NOAA Weather Radio, local radio or television, or the Internet) and bring a sweater or jacket with you if your location has a cooler forecast.

Be aware that sometimes August can be very humid with poor seeing conditions. And, the closer to the horizon, the worse the seeing conditions could be.

Binoculars and telescopes are not very useful for finding meteors. Meteors streak across the sky in a very brief 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 (perhaps on a blanket, sheet, or beach-towel—or possibly in a reclining beach or lawn-chair), in an area with a good view of the entire sky (with few obstructions such as buildings, trees or hills, perhaps at a higher elevation), and keep scanning the entire sky with your naked-eyes (one-power).

Meteor showers appear to emanate from a radiant point in the sky. For the Perseid Meteor Shower, the radiant appears to be within the Constellation Perseus, named for the hero of Greek mythology. 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. 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.

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, often high 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 fire-balls. 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, leaving behind a trail of dust and grit. Comet Swift-Tuttle was discovered in 1862 and last returned for viewing in 1992.

Comet Swift-Tuttle measures about 16 miles / 25 kilometers across, much larger than the object that is thought to have fallen to Earth which resulted in the extinction of the dinosaurs (about 6 miles / 10 kilometers across) approximately 66 million years ago (after living on Earth for about 165 million years!).

Comet Swift-Tuttle will make a very close approach to the Earth in the year A.D. 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".

So, the time for viewing is right, and the less moonlight is great. And, of course, with the warm weather most of us experience in the Northern Hemisphere, this time of year, what could be better for viewing meteors?

Of course, meteor showers, like all celestial observations, are weather-permitting. Even a few clouds could obscure quite a few meteors.

If the weather in your area does not permit direct viewing outdoors of this meteor shower, it is possible (but not guaranteed) you may be able to use Google, Yahoo, Bing, Lycos, or your favorite Internet search engine to find special web-casts of the meteor shower at one or more sites on the Internet.

A cautionary note for those who find it necessary to watch the meteor shower on the Internet. The video camera, used for each web-cast, can only aim at one part of the sky at a time. Hence, do not expect to see as many meteors as you might see with your own eyes outside. Outdoors, you can easily scan the entire sky for meteors, while a camera aimed at one area of the sky will only be able to see the meteors that enter that particular field-of-view.

Internet Links  to Additional Information ----

Perseid Meteor Shower: Link >>> https://en.wikipedia.org/wiki/Perseids

Comet Swift-Tuttle: Link >>> https://en.wikipedia.org/wiki/Comet_Swift%E2%80%93Tuttle

Constellation Perseus: Link >>> https://en.wikipedia.org/wiki/Perseus_%28constellation%29

Meteor Shower: Link >>> https://en.wikipedia.org/wiki/Meteor_shower

Meteor: Link >>> https://en.wikipedia.org/wiki/Meteoroid#Meteor

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

Meteorite: Link >>> https://en.wikipedia.org/wiki/Meteoroid#Meteorites

Fifth largest fragment of the meteorite which struck Barringer Meteor Crater near Winslow, Arizona, which was displayed (1939 to 1991) at the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science and technology museum from 1939 to 1991. Today, this meteorite is displayed on the second floor of Pittsburgh's Carnegie Science Center, next to the Henry Buhl, Jr. Planetarium:
Link >>> http://buhlplanetarium2.tripod.com/Buhlexhibits.htm#meteorite

Related Blog-Posts ---

"Tonight's 'Meteor Outburst' w/Web-Casts: 150 Years After Comet-Meteor Shower Link Found." Thur., 2016 Aug. 11.

Link >>> https://spacewatchtower.blogspot.com/2016/08/tonights-meteor-outburst-wweb-casts-150.html

 

"Great Perseid Meteor Shower Peaks Wed. Night w/ Web-Casts." Wed., 2015 Aug. 12.

Link >>> https://spacewatchtower.blogspot.com/2015/08/great-perseid-meteor-shower-peaks-wed.html

 

"Perseid Meteor Shower Peaks in Sky & Web-Casts." Tue., 2014 Aug. 12.

Link >>> https://spacewatchtower.blogspot.com/2014/08/perseid-meteor-shower-peaks-in-sky-web.html

 

"Perseid Meteor Shower Peaks Sun., Mon. Nights." Sat., 2013 Aug. 10.

Link >>> https://spacewatchtower.blogspot.com/2013/08/perseid-meteor-shower-peaks-sun-mon.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Monday, 2020 August 10.

                             Like This Post?  Please Share!

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

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

gaw

Glenn A. Walsh, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Thursday, August 6, 2020

Female Astrophysicist Helped Build 1st Atomic Bomb

                           Leona Woods.jpeg
           Photograph of Leona Woods Marshall at the University of Chicago on 1946 December 2.
(Image Sources: Wikipedia.org, By Argonne National Laboratory - Leona Woods Marshall Libby, Uranium People, pp. 182-183, Public Domain, https://commons.wikimedia.org/w/index.php?curid=25600002)

By Glenn A. Walsh
Rep. 5orting for SpaceWatchtower

Today marks 75 years since the first use of nuclear weapons in war-time, the culmination of the American Manhattan Project (named for the Manhattan District of the U.S. Army Corp of Engineers). It was at 8:16 a.m. Japan Standard Time (JST) on the morning of 1945 August 6 [Aug. 5, 7:16 p.m. Eastern War Time (EWT) / Aug. 5, 23:16 Coordinated Universal Time (UTC)] that the United States dropped the first atomic bomb on Hiroshima, Japan.

One of the very few female scientists who worked on the Manhattan Project went on to become a researcher in high-energy physics, astrophysics, cosmology, and diatomic molecular spectroscopy.

Leona Woods, later known as Leona Woods Marshall Libby, was the youngest (at age 23) and only female member of Enrico Fermi's team at the University of Chicago that built and experimented with the world's first artificial nuclear reactor. During the experimentation, Leona Woods was instrumental in the construction and then utilization of Geiger counters for analysis. When the first nuclear reactor went critical on 1942 December 2, she was the only woman present.

Leona Woods worked with Enrico Fermi on the Manhattan Project until 1943. Then in 1944, Leona Woods Marshall, with her first husband John Marshall (who was the great-great-great-grandson of US Supreme Court Justice John Marshall), moved to Hanford, Washington to work with the nuclear reactor creating plutonium for the Manhattan Project.

They helped solve the problem of xenon-135 "poisoning" at the  plutonium production site, which had stopped production. Leona Marshall also supervised the construction and operation of Hanford's plutonium production reactors.

She had been selected for the Manhattan Project due to her expertise in creating vacuums needed for boron trifluoride counters, for measuring neutrons and creating a nuclear chain reaction.

Leona Woods is considered the most accomplished of the few women working on the Manhattan Project. She had graduated high school in 1934 at age 14 and earned a B.S. degree in chemistry from the University of Chicago in 1938 at age 19.

Leona Woods completed her graduate work in chemistry in 1942. Her graduate supervisor was the future Nobel Laureate Robert S. Mulliken (who had been taught at the University of Chicago by Nobel Laureate Robert A. Millikan).

After World War II, she became a fellow at Erico Fermi's Institute of Nuclear Studies at the University of Chicago. In 1957 after a separation from her husband, she went to work at the Institute for Advanced Study at Princeton University in Princeton, New Jersey; at the time she was a single mother. The next year she became a fellow at the Brookhaven National Laboratory on New York's Long Island.

At New York University, she became an associate professor of atomic and nuclear physics in 1962.

From 1964 to 1970, she was a research professor in astrophysics and cosmology, as well as high-energy physics, at the University of Colorado. She also became a staff member at the RAND Corporation, a position she maintained until 1976.

In 1966, she divorced John Marshall and married Nobel Laureate Willard Libby. Willard Libby won the 1960 Nobel Prize in Chemistry for his contributions to the team that developed radio-carbon-14 dating, a process which revolutionized archeology and paleontology.

In 1973, Leona Woods Marshall Libby joined her husband at the University of California at Los Angeles as a visiting professor of environmental studies, engineering, engineering archaeology, mechanical aerospace, and nuclear engineering. Like her husband, she was a strong advocate for food irradiation as a way to kill harmful bacteria; she supported relaxing regulations on the use of food irradiation.

Over her life-time, she published more than 200 scientific papers. This included papers and books on early atomic research and environmental issues, as well as astrophysics topics.

In 1982, she edited Willard Libby's papers and published, with Rainer Berger, The Life Work of Nobel Laureate Willard Libby. Her husband had died two years earlier.

A 1969 paper she wrote was titled, Creation of an Atmosphere for the Moon, which she wrote for the RAND Corporation. In 1980, she wrote The Upside Down Cosmology and the Lack of Solar Neutrinos. She also published a paper titled, Venusian Geography.

Her last paper, produced in 1984, was on quasi-stellar objects or quasars.

She died at age 67, of an anesthesia-induced stroke, on 1986 November 10. She had been born on 1919 August 9.

Leona Woods Marshall Libby always felt that developing the atomic bomb was necessary, particularly since the Germans were working on the same project. She was also very concerned with the realistic expectation of a great loss of American soldiers and sailors had an invasion of Japan been considered necessary.

Regarding the advancement of nuclear science, she once said, “You can’t stop it. How can you stop it? You’re going to tell a guy like [Muammar] Gaddafi, ‘Don’t buy that bomb from the Israelis,’ or wherever you’re going to buy it? You can tell him, and he’s going to do—I mean you cannot stop the wheels. That’s my view. And again, the do-gooders and the crying on shoulders, these guys have got blue-eyed optimism that is not useful.”

Internet Links to Additional Information ---

More on Leona Woods Marshall Libby:
Link 2 >>> https://www.lindahall.org/leona-

Astronomy & World War II

woods/ 

Oral History Interview (1986) - Leona Woods Marshall Libby:

Related Blog Posts ---

"Requirement for World War II D-Day: Full Moon !" Thur., 2019 June 6.

Link >>> https://spacewatchtower.blogspot.com/2019/06/requirement-for-world-war-ii-d-day-full.html


"Astronomy & World War II." Sun., 2014 Sept. 7.

Link >>> https://spacewatchtower.blogspot.com/2014/09/astronomy-world-war-ii.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Thursday, 2020 August 6.

                             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, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Saturday, August 1, 2020

Astro-Calendar: 2020 August / 1st SpaceX Crew Dragon Splash-down Aug. 2


NASA astronauts Robert Behnken and Douglas Hurley (shown during a pre-flight test on 2020 March 30) will return to Earth on the SpaceX Crew Dragon on Sunday Afternoon, August 2, weather-permitting. The first splash-down of a crewed American spacecraft, since the Apollo-Soyuz Test Project on 1975 July 24, is planned to occur on the Crew Dragon Demo-2 flight, after leaving the International Space Station (ISS) on the evening of Saturday, August 1.
More Information & Video Coverage of the Return to Earth including Undocking from the Space Station & Spash-down: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2020.html#spacex2
(Image Source: NASA)

Astronomical Calendar for 2020 August ---
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2020.html#aug

 Related Blog Post ---

"Astro-Calendar: 2020 July / 50 Years of Video Calling."

Wednesday, 2020 July 1.

Link >>> https://spacewatchtower.blogspot.com/2020/07/astro-calendar-2020-july-50-years-of.html


Source: Friends of the Zeiss.
              Saturday, 2020 August 1.

                             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, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Monday, July 27, 2020

Thur.-AM U.S. Joins China & U.A.E in Race to Mars; Watch Launch Live

https://upload.wikimedia.org/wikipedia/commons/e/e5/PIA23882-MarsHelicopterIngenuity-20200429_%28trsp%29.png
Photograph of the first interplanetary helicopter to be flown on Mars early next year, following the landing of the NASA Mars 2020 mission to be launched on Thursday.
(Image Sources: NASA, Jet Propulsion Laboratory / California Institute of Technology, Wikipedia.org, By NASA/JPL-Caltech - https://photojournal.jpl.nasa.gov/jpeg/PIA23882.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=89835966)

By Glenn A. Walsh
Reporting for SpaceWatchtower

Thursday morning, NASA plans to launch the third space probe bound for Mars this month. NASA's Mars 2020 mission, including the Perseverance Rover and the first interplanetary helicopter, will join space probes from China and the United Arab Emirates traveling to Mars.

The launch of the NASA Mars 2020 mission will be broadcast, live, on NASA Television. An Internet link to NASA-TV is near the end of this blog-post.

Launch of the NASA Mars 2020 mission is scheduled for this-coming Thursday Morning, 2020 July 30 at 7:50 a.m. Eastern Daylight Saving Time (EDT) / 11:50 Coordinated Universal Time (UTC), on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. It is scheduled to land in Mars' Jezero Crater on 2021 February 18 at 3:00 p.m. Eastern Standard Time (EST) / 20:00 UTC.

Last Thursday (July 23), China launched their first mission to Mars (although a 2011 joint Russian-Chinese mission to Mars had a failed launch), expanding their rivalry with the United States into Deep Space. Named Tianwen-1 (Chinese for "Questions to Heaven" – from a classical poem that has verses about Outer Space), the five-ton spacecraft includes a Mars orbiter, a lander and a rover to study the Martian soil.

China has been working for a couple decades to match American supremacy in Outer Space, with a military-led space program. In 2003, China became just the third nation to launch astronauts into Earth orbit. China has sent two rovers to the Moon, including the very first one landing on the far side of the Moon (the side of the Moon that always faces away from Earth - not the “dark side of the Moon”). And, China is planning to launch a permanent space station into Earth orbit by 2022.

A surprise entry into the race to Mars is the first interplanetary spacecraft to be launched from the Arab world. The previous Monday (July 20 – the 51st anniversary of the first landing of U.S. astronauts on the Moon), the United Arab Emirates (U.A.E.) launched a space probe (from the Tanegashima Space Center in Japan) named Al-Amal (Arabic for Hope) to enter into orbit around the planet Mars, to study the planet's weather and atmosphere. Although this mission does not include a landing on Mars, the probe is expected to stay in orbit for at least one Martian year – 687 Earth days.

Led by Emirati engineers and scientists (women make-up 80 per-cent of their science team!), this mission is a collaboration with four U.S. institutions: University of California at Berkeley, University of Colorado at Boulder, Arizona State University, and Northern Arizona University.

While the U.S., Russia, and China have gotten all of the headlines for space exploration probes, the U.A.E already has nine functioning satellites in Earth orbit, launched the first Arab astronaut (on a Soyuz spacecraft from Kazakhstan) to the International Space Station (ISS) last September, and has a stated goal of establishing a human colony on Mars by the year 2117! Inspiring Arab youth is one of the major goals of the U.A.E. space program, to recall the Middle Ages when Arab scientists and mathematicians made several scientific advances.

The reason all three Mars missions are launching this month is to take advantage of a favorable alignment, between Earth and Mars, which occurs, on average, once every two years and 50 days. At this time Earth, in its closer orbit to the Sun, overtakes the slower Mars; Earth takes 365.256 days to orbit the Sun, while Mars' solar orbit lasts 687 Earth days.

It is at this time, when Earth and Mars are closest, that the travel time to Mars is much shorter (and the cost of a Mars mission is much lower). Each of these three missions will take approximately seven months to reach Mars.

This is also the best time to view Mars in the sky. Again, once every two years Mars appears larger and brighter to amateur astronomers and other planet and stargazers. Mars will appear the best in the second half of this year.

The NASA Mars 2020 mission includes the Perseverance Rover, which was designed with the assistance of the Curiosity Rover engineering team, to create a more robust Mars rover. The Perseverance Rover will have a major astrobiology mission, as well as investigate the planet's geology.

During its travels on the planet, Perseverance will collect soil samples and store the samples in special containers. NASA expects to retrieve these sample containers and return them to Earth for scientific analysis, during a potential, future Mars sample-return mission.

A Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) will power the Perseverance Rover. Left-over as a back-up unit for NASA's Curiosity Rover (which has been operating on Mars since 2012 August 6), it was provided to NASA by the U.S. Department of Energy.

It provides a steady supply of heat that is converted to electricity for use by the rover, without the concern that solar energy panels would be adversely affected by the Martian night-time, dust storms, and low sunlight during the Mars Winter. The MMRTG is expected to have a 14-year operational life-span and will be assisted by two lithium-ion rechargeable batteries.

A novel, new tool included with this mission is the Mars Helicopter Ingenuity drone, the first such helicopter deployed beyond Earth. This will be a test for this robotic technology, which could be included on future missions to planets and moons having atmospheres.

The primary mission of Perseverance is to investigate Jezero Crater, which scientists believe may have been an 820-foot / 250-meter-deep lake 3.9 billion to 3.5 billion years ago. This crater seems to have an ancient river delta, where flowing water could have deposited a great deal of sediment during the millions of years that water may have existed on the planet's surface.

Similar such areas on Earth are known to preserve microscopic fossils for billions of years. If life once existed on Mars, scientists believe this may be one of the best spots to search for similar micro-fossils.

NASA Television - Scheduled, Live Coverage of Mars 2020 Launch Begins Thursday, 2020 July 30 at 7:00 a.m. EDT / 11:00 UTC:
Link >>> https://www.nasa.gov/multimedia/nasatv/#public

Internet Links to Additional Information ---

Planet Mars: Link >>> https://en.wikipedia.org/wiki/Mars

NASA Mars 2020 Mission:
Link 1 >>> https://www.nasa.gov/perseverance
Link 2 >>> https://en.wikipedia.org/wiki/Mars_2020

NASA Perseverance Rover: Link >>> https://en.wikipedia.org/wiki/Perseverance_(rover)

NASA Mars Helicopter Ingenuity:
Link >>> https://en.wikipedia.org/wiki/Mars_Helicopter_Ingenuity

China Tianwen-1 Space Probe to Mars:

United Arab Emirates Al-Amal Space Probe to Mars:

Related Blog Posts ---

"Public Invited to Vote to Name NASA's Mars 2020 Rover--By This Monday, Jan. 27." 2020 Jan. 23.

Link >>> https://spacewatchtower.blogspot.com/2020/01/public-invited-to-vote-to-name-nasas.html



"For Students: Mars 2020 Name the Rover Essay Contest By Nov. 1." 2019 Oct. 15.

Link >>> https://spacewatchtower.blogspot.com/2019/10/for-students-mars-2020-name-rover-essay.html

 

"Place Your Name on Mars 2020 Rover Microchip By This Monday, Sept. 30." 2019 Sept. 26.

Link >>> https://spacewatchtower.blogspot.com/2019/09/place-your-name-on-mars-2020-rover.html

 

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Monday, 2020 July 27.

                             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, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Wednesday, July 22, 2020

Comet NEOWISE Still Visible; Passes Earth Wed. Night / Thur. AM

Comet 2020 F3 (NEOWISE) on Jul 14 2020 aligned to stars.jpg
Image of Comet NEOWISE taken with a 15-minute exposure from Germany on 2020 July 14.
(Image Sources: Wikipedia.org, By SimgDe - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=92294694)

By Glenn A. Walsh
Reporting for SpaceWatchtower

There is still time to view Comet NEOWISE, now visible in the evening sky at northern latitudes.

Officially called Comet 2020 F3 (NEOWISE), it will pass the Earth on Wednesday evening / Thursday morning (Wednesday night at 9:14 p.m. Eastern Daylight Saving Time (EDT) / Thursday at 1:14 UTC), at a distance of 64 million miles  / 103 million kilometers. As of July 18, the apparent visual magnitude of Comet NEOWISE was about +3, making it one of the brightest comets visible from Earth's Northern Hemisphere since Comet Hale-Bopp was observed in 1997.

Comet NEOWISE has already gone around the Sun and is headed back into the outer Solar System, with its closest solar approach occurring on July 3, at a distance from the Sun of 27 million miles / 43 million kilometers. Until now, the comet's orbital period was about 4400 years; with this most recent passage of the Sun, it will now take about 6700 years to return to the inner Solar System.

Stars are pinpoints of light, while a comet is much more diffuse, shining by reflected light from the Sun. So, a star of a certain apparent visual magnitude is much easier to spot than the fuzzy head of a comet of the same magnitude.

Although some say Comet NEOWISE can be seen with the naked-eyes (one-power), it would appear very diffuse, like a small, fuzzy blob. You really need binoculars or a small telescope to find it in the sky. And, you will not be able to notice the comet tail (which points-up, away from the Sun) without binoculars or a telescope.

Once found with binoculars or a telescope, you may, then, be able to look in the sky with your naked-eyes (one-power) and see the comet. It would be more likely visible with naked-eyes when using averted-vision. Using averted-vision is when you do not look directly at an object, but look somewhat away from the object of interest, viewing the object of interest at the edge of an eye's vision. Averted-vision is more sensitive than an eye's central vision.

This week, Comet NEOWISE is located about half-way between the Big Dipper and the horizon, when you look in the west-northwest sky about 30-to-45 minutes after sunset. Beyond that time each evening this week, the comet gets lower in the sky and sets.

Each day, the comet is a little higher in the sky, and a little further to the west (i.e. to the left). By July 23 and beyond, the comet will be to the lower-left of the Big Dipper, getting higher each day so by July 25 it will be to the left of the Big Dipper but a little lower in the sky.

This week will probably be the last good week for viewing the comet. Each day, as the comet gets further from the Sun, the comet nucleus becomes dimmer as it reflects less sunlight.

Although the best views will come at northern latitudes, including in the United States and Canada, it may be visible a little further south, such as in the southern United States. However, in the southern states the comet would appear much closer to the horizon; hence, a good, unobstructed horizon would be essential for viewing. The comet is not visible in the Southern Hemisphere.

As with all celestial observing, viewing this comet is always weather-permitting. For an object as diffuse or "fuzzy" as a comet, you need as clear as sky as possible. Clouds could make it quite difficult to locate a comet, even with binoculars or a telescope. Particularly in the Summer months when the sky can be rather humid, the lower in the sky the more difficult it will be to find a comet or any dim celestial object.

Also, city lights and Moon-light would brighten the sky making it more difficult to find dim objects.  It would be best to find an observing site away from city lights, for the best chance to find a comet. And, if possible, you want to try to look for a comet at a time when a large, bright Moon is not in the sky.

Fortunately, the Moon passed the New Moon Phase on Monday afternoon (2020 July 20 at 1:33 p.m. EST / 17:33 UTC - the 51st anniversary of the first landing of U.S. astronauts on the Moon), so Moon-light should not be a problem this week. In fact, later in the week you may also see a slim, waxing crescent Moon in the western sky.

At the following Internet link is a graphic, from EarthSky.org, which shows the location of the comet in the sky for the next few days:


Internet Links to Additional Information ---

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

Comet 2020 F3 (NEOWISE): Link >>> https://en.wikipedia.org/wiki/C%2F2020_F3_(NEOWISE)

Averted-Vision: Link >>> https://en.wikipedia.org/wiki/Averted_vision

Related Blog-Posts ---

"4 Comets May Be Visible w/ Small Telescopes." Wed., 2017 April 12.

Link >>> https://spacewatchtower.blogspot.com/2017/04/4-comets-may-be-visible-w-small.html

 

"Two Dim Comets May Be Visible in a Telescope." Sun., 2017 Feb. 19.

Link >>> http://spacewatchtower.blogspot.com/2017/02/two-dim-comets-may-be-visible-in.html

 

"Comet Lovejoy: Best View Next 2 Weeks." Wed., 2015 Jan. 7.

Link >>> https://spacewatchtower.blogspot.com/2015/01/comet-lovejoy-best-view-next-2-weeks.html


"Meteor Shower & Comet Part of Busy Weekend in Astronomy." Sat., 2015 Jan. 3.

Link >>> http://spacewatchtower.blogspot.com/2015/01/meteor-shower-comet-part-of-busy.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Wednesday, 2020 July 22.

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gaw

Glenn A. Walsh, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Thursday, July 16, 2020

Have Smart-Phone? Help NASA Document Satellite Streaks in Night Sky


This image of the night sky shows at least 19 streaks caused by the motion of the second batch of StarLink satellites launched on 2019 November 20. This 333-second photographic exposure was taken by astronomers Clara Martínez-Vázquez and Cliff Johnson using the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO) in northern Chile.
(Image Sources: Wikipedia.org, By NSF’s National Optical-Infrared Astronomy Research Laboratory/CTIO/AURA/DELVE - https://nationalastro.org/news/starlink-satellites-imaged-from-ctio/, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=89537986)

By Glenn A. Walsh
Reporting for SpaceWatchtower

With more than 500 “StarLink” satellites already placed in Earth orbit by SpaceX, scientists, photographers, Indigenous communities, and other stargazers are concerned that space clutter will endanger the view of the night sky that human-kind has enjoyed for millenia. Now, NASA is asking anyone with a smart-phone to photo-document the satellite streaks in the night sky, as more and more of these satellites enter Earth orbit.

A new Citizen Science Project, the Satellite Streak Watcher research project, asks amateur astronomers, photography enthusiasts, and anyone else interested to use their smart-phones to document the increasing number of satellite streaks in the night sky. All that you need is a smart-phone camera or other digital camera, a tripod to hold the camera steady, and long photographic exposures on dark, clear evenings or early mornings.

The best time to take these digital pictures is within the 90 minutes after sunset and within the 90 minutes before sunrise. Although the Sun is no longer shining on a portion of the planet during these time periods, the Sun still shines on the satellites in low-Earth orbit and will provide bright streaks on long-exposure photographs showing these satellites traveling through the sky.

SpaceX plans to launch around 12,000 StarLink satellites to help spread Internet access around the globe, with these space-based satellite systems. Other corporations, including Amazon, may launch even more “constellations” of Internet communication satellites.

This is in addition to the approximately 2,000 active satellites in orbit right now, as well as many de-commissioned satellites and other space junk. Within another decade or so, there could be upward of 40,000 active satellites in Earth orbit!

To be effective in relaying Internet access, low-Earth orbit is more advantageous. But, the lower the orbit the brighter a satellite appears in the night sky. More such satellites to cover the entire globe are needed when they are placed in a lower orbit, which even aggravates the situation. And, when each of these satellites is de-commissioned, it will add to the amount of space junk in orbit.

With all of these new, low-Earth orbit satellites, many astronomers are concerned that the sky may become so cluttered that astronomical research will be at risk. With so many streaks appearing in the night sky photographs astronomers use to study the cosmos, the study of deep space objects becomes extremely problematic.

Although SpaceX has promised to make future satellites with a darker, less reflective tint, it still is unclear that this will help the situation. However, satellite companies prefer a reflective surface on their satellites to reduce heat absorption from solar radiation.

For more than a century, scientific and educational institutions have tried to locate major astronomical observatories in remote areas away from large metropolitan cities, to avoid light pollution as well as other air pollutant sources. However, light pollution from a source in Earth orbit cannot be avoided from any place on the planet.

NASA wants to document the problem, for possible, future remediation efforts. So, if you have the interest and the proper equipment, perhaps you can help NASA photo-document these satellite streaks in the night sky and upload these images to the Satellite Streak Watcher research project.

Internet Links to Additional Information ---

Satellite Streak Watcher research project:
Link >>> https://www.anecdata.org/projects/view/687

SpaceX StarLink Satellites: Link >>> https://en.wikipedia.org/wiki/Starlink

Other Citizen Science Projects:
Link >>> http://buhlplanetarium2.tripod.com/FAQ/citizenscience.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Thursday, 2020 July 16.

                             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, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >

Saturday, July 4, 2020

Dim Lunar Eclipse Visible in Western Hemisphere Sat. Night / Sun. Morning

                                           
                                              Photographs of a Penumbral Lunar
                                              Eclipse / Penumbral Eclipse of the
                                              Moon in January of 1999 shows the
                                              dimming of the Southern Hemisphere
                                              (top half of the Moon in these photos)
                                              of the Moon (left photo) compared to
                                              the Moon seen outside of the Earth's
                                              shadow (right photo).
                                              (Image Sources: Wikipedia.org , By SockPuppetForTomruen (talk) - I
                                                             created this work entirely by myself. Transferred from en.wikipedia, Public
                                                             Domain, https://commons.wikimedia.org/w/index.php?curid=17097701)


By Glenn A. Walsh
Reporting for SpaceWatchtower

Late Saturday evening into Sunday morning, very observant viewers in most of Earth's Western Hemisphere (as well as most of Africa and Western Europe) may be able to see a dim Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon.

A Lunar Eclipse / Eclipse of the Moon is the type of eclipse which is safe to look at with the naked-eyes (one-power), binoculars, and telescopes.

During a Lunar Eclipse / Eclipse of the Moon, the Earth's solar shadow shines on part or all of the Moon, at or very close to the time of the Full Moon phase. The Earth actually casts two shadows: the main and darker Umbral Shadow along with the secondary and dimmer Penumbral Shadow.

In the case of a Total Lunar Eclipse / Total Eclipse of the Moon, the Earth's Umbral Shadow completely envelops the Moon. In the case of a Partial Lunar Eclipse / Partial Eclipse of the Moon, only part of the Moon is covered by the Umbral Shadow.

In the case of a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon, only the dimmer Penumbral Shadow covers part or all of the Moon. A Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon is dimmer than a Partial Lunar Eclipse / Partial Eclipse of the Moon.

Of course, weather conditions have to be clear to have a chance to see this eclipse. However, the shading of the Moon during such a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon is extremely subtle, and not everyone may be able to tell when the eclipse is occurring.

One strategy for successfully observing a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon could be the following: Note the time of greatest eclipse (given below); first look at the Moon a couple hours before the time of greatest eclipse; then, follow the Moon as the eclipse progresses and see if you can notice the dimming of the Moon's image.

And, if you have a light-meter, you could take measurements a couple hours before the eclipse, and while the eclipse is progressing.

This Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon could be visible to viewers in South America, most of North America (except Alaska, the northern-most sections of Canada, and Iceland), southern tip of Greenland, most of Africa, Western Europe, Atlantic Ocean, and most of the Pacific Ocean.

       Times of Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon Eclipse Phases

             (EDT = Eastern Daylight Saving Time; UTC = Coordinated Universal Time)

                                Saturday, 2020 July 4 to Sunday, 2020 July 5

Penumbral Lunar Eclipse Begins:                                    11:07:23 p.m. EDT / 3:07:23 UTC
Greatest Penumbral Lunar Eclipse:                                  12:30:02.2 a.m. EDT / 4:30:02.2 UTC
Primary Moon Phase - Full Moon:                                      12:44 a.m. EDT / 4:44 UTC
Penumbral Lunar Eclipse Ends:                                           1:52:27 a.m. EDT / 5:52:27 UTC

Special Note: Although the times given for the beginning and ending of the Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon are the correct times, it is highly unlikely that the beginning and ending can be viewed visually. On average, a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon is only visible approximately one-half-hour before until one-half-hour after the time of greatest eclipse.

Actual observations with precise times, of when such an eclipse is first visible and when the eclipse is no longer visible, would be valuable information for research scientists. Precise times can be determined from government time service radio stations, such as the following stations serving North America ---

  • Short-Wave: WWV, U.S. National Institute of Standards and Technology
  • Short-Wave: WWVH, U.S. National Institute of Standards and Technology
  • Short-Wave: CHU, National Research Council of Canada
  • Consumer “Atomic Clocks” Corrected Periodically by Long-Wave Radio Station WWVB, U.S. National Institute of Standards and Technology

SPECIAL ALERT: Do not confuse a Lunar Eclipse / Eclipse of the Moon with a Solar Eclipse / Eclipse of the Sun. Never look directly at any Solar Eclipse / Eclipse of the Sun unless you have the proper equipment and proper training to do so safely! Otherwise, eye-sight could be damaged, permanently!

SOLAR ECLIPSE / ECLIPSE OF THE SUN: TIPS FOR SAFE VIEWING:
Link >>> http://buhlplanetarium2.tripod.com/FAQ/soleclipse/solareclipseviewingtips.html

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

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

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

And, this year's July 5 Full Moon is also known, in Earth's Northern Hemisphere, as the Short-Night Moon. This is due to the fact that it is seen in the sky for less time in one night than any other Full Moon of the year, due to its low astronomical declination in the sky.

As the Sun appears high in the sky (high in astronomical declination) near the Summer Solstice (which was June 20), at the same time of the year the Moon appears to travel low in the sky resulting in a later Moon-rise and an earlier Moon-set.

Most years the Full Moon of June is the Short-Night Moon. However, since this year's July Full Moon is closer to the Sumner Solstice than the June Full Moon, the July Full Moon is the Short-Night Moon for 2020.

Also, Saturday (2020 July 4), in addition to being U.S. Independence Day, is Earth Aphelion Day, the one day when Earth is farther from the Sun (at 8:00 a.m. EDT / 12:00 UTC, at a distance of 94,507,634.78783841 statute miles / 152,095,295 kilometers) than any other day of the year. Although the coldest time of the year, the Earth's closest approach to the Sun actually occurred on January 5 at 2:47 a.m. EST / 7:47 UTC (91,398,199 statute miles / 147,091,144 kilometers).


Internet Links to Additional Information ---

Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon, 2020 July 4 to 5 --
More Information:
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2020.html#luneclipse20200705

More about a Lunar Eclipse / Eclipse of the Moon:
Link >>> https://en.wikipedia.org/wiki/Lunar_eclipse

Related Blog Posts ---

"Dim Lunar Eclipse in Eastern Hemisphere Friday / Saturday." Fri., 2020 June 5.
Link >>> https://spacewatchtower.blogspot.com/2020/06/dim-lunar-eclipse-visible-in-eastern.html

"Dim Penumbral Lunar Eclipse Early Wed. Morning" Tue., 2016 March 22.
Link >>> https://spacewatchtower.blogspot.com/2016/03/dim-penumbral-lunar-eclipse-early-wed.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Saturday, 2020 July 4.

                             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, Informal Science Educator & Communicator:
http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania.
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 >