India Launches Rover to Probe Moon's South Pole

                             
In the 1980s, photographs of the Moon's South Pole, similar to the photo above (which is a photo of the waxing crescent Moon), were taken using the rather unique 10-inch Siderostat-type Refractor Telescope, in the third floor astronomical "People's Observatory" of 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), by American Lunar Society Founder Francis G. Graham, as part of a national research project to better map the area near the Moon's South Pole. Yesterday, India launched an unmanned rover probe to explore the Moon's South Pole. 
(Image Source: Friends of the Zeiss)

By Glenn A. Walsh

Reporting for SpaceWatchtower

Yesterday (Monday, 2019 July 22), India launched a space probe and rover bound for the South Pole area of Earth's Moon. The launch, which had been delayed since July 15 due to technical problems, came just a couple days after the 50^th anniversary of the first humans, American astronauts Neil Armstrong and Buzz Aldrin, to set-foot on the Moon.

If this mission is successful, India will become the fourth Earth nation to soft-land a probe on the Moon. Up until now, only the United States, Russia, and China have successfully soft-landed probes on the Moon. On January 3, China became the first nation to soft-land a probe on the far side of the Moon, the Chang'e 4 Lander and Rover.

On April 11, the Beresheet Lunar Lander, developed by Israel's private SpaceIL organization and launched from Cape Canaveral by SpaceX, attempted a soft-landing on the Moon. However, the robotic probe crashed on the lunar surface due to a main engine failure in the final descent.

The Indian Space Research Organization (ISRO) named the new space probe Chandrayaan-2, which translates from Sanskrit to mean “Moon vehicle.” The probe was launched from the Satish Dhawan Space Center at Sriharikota in Andhra Pradesh state on July 22 at 2:43 p.m. local time / 5:13 a.m. Eastern Daylight Saving Time (EDT) / 9:13 Coordinated Universal Time (UTC).

The first Indian probe sent to the Moon, Chandrayaan-1, was a lunar orbiter and impacter which was launched on 2008 October 22. It entered lunar orbit on 2008 November 8 and operated until August of 2009. In a controlled manner, the Chandrayaan-1 Moon Impact Probe separated from the orbiter and struck near the Shackleton Crater, near the South Pole, on 2008 November 14. The probe strike ejected sub-surface soil, which was analyzed to determine if water-ice was present. After evaluating the data from the impact probe, Indian scientists confirmed that water existed in the lunar soil near the South Pole.

Weighing 3.8 tons, Chandrayaan-2 consists of an orbiter, lander, and rover and carries 13 payloads. It will travel for 2 months before settling into a circular orbit 62 miles / 100 kilometers above the lunar surface.

The space probe's lander, named Vikram (for Indian space pioneer Vikram Sarabhai), will then land near the South Pole. Vikram will confirm the technology to soft-land on the lunar surface.

A robotic rover named Pragyan (meaning “wisdom”), after separating from the lander, will travel near the South Pole area for a half-month (the amount of time sunlight will be available). Vikram and Pragyan will collect mineral and chemical samples from the lunar surface, sending the data back to India. The primary goal of the mission is to study the water-ice and determine the amount of water available near the South Pole.

The orbiter will map the surface of the Moon and evaluate what can be found of an outer atmosphere of the Moon.

India plans to launch a Chandrayaan-3 mission to the Moon in the 2023-2024 period. In 2014, India became the first Asian nation to put a probe (Mangalyaan) into orbit around the planet Mars. ISRO is also considering putting a probe in orbit of the planet Venus by 2023.

ISRO hopes to send Indian astronauts into Earth orbit by 2022. The Indian space agency also plans on launching their own space station into Earth orbit by 2030.

Even up until the 1980s, the South Pole was one area of the Moon that was not well mapped. As part of a national research project in the 1980s to better map the Moon's South Pole area, photographs of the Moon were taken by American Lunar Society Founder Francis G. Graham using the rather unique 10-inch Siderostat-type Refractor Telescope, in the third floor astronomical observatory of 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).

Although Buhl Planetarium's “People's Observatory” was primarily used as a public observatory to educate the general public, particularly students, from time-to-time the City of Pittsburgh-owned telescope was used for scientific research.

At the time, Francis G. Graham was a Buhl Planetarium and Observatory Lecturer. Today, he is Professor Emeritus of Physics at Kent State University.

Internet Links to Additional Information ---

Indian Chandrayaan-2 Space Probe:
Link 1 >>> http://www.planetary.org/explore/space-topics/space-missions/chandrayaan-2.html
Link 2 >>> https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=CHANDRYN2
Link 3 >>> https://en.wikipedia.org/wiki/Chandrayaan-2

Indian Space Research Organization (ISRO):
Link 1 >>> https://www.isro.gov.in/
Link 2 >>> https://en.wikipedia.org/wiki/Isro

Buhl Planetarium's “People's Observatory” & 10-inch Siderostat-type Refractor Telescope:

Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html

Related Blog Posts --

"American Lunar Society Founder on 50th Anniversary: 1st Humans Walk on Moon !, KOKH’S QUESTION: After 50 Years, Why No Lunar Settlements ?"

2019 July 16.

Link >>> http://spacewatchtower.blogspot.com/2019/07/american-lunar-society-founder-on-50th.html

"American Lunar Society Founder on 50th Anniversary: 1st Humans Orbit Moon, The Incredible Legacy of Apollo 8." 2018 December 24.

Link >>> http://spacewatchtower.blogspot.com/2018/12/50th-anniversary-incredible-legacy-of.html

 

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Tuesday, 2019 July 23.

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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 >

American Lunar Society Founder on 50th Anniversary: 1st Humans Walk on Moon !

     
Historic plaque on the ladder of the Lunar Excursion Module (LEM), "Eagle," commemorating the first human landing site on the Moon. (Image Sources: NASA, Wikipedia.org: Public Domain)

Editor's Note: Precisely 50 years ago, from the time of the posting of this blog-post, NASA's Apollo 11 spacecraft launched from the Kennedy Space Center, Florida at 9:32 a.m. Eastern Daylight Saving Time (EDT) / 13:32 Coordinated Universal Time (UTC) on Wednesday, 1969 July 16. Four days later, Neil Armstrong and Buzz Aldrin would become the first humans to step onto another world, the Earth's Moon. The following is a brief essay regarding the historical and scientific significance of the Apollo 11 mission, as well as possible reasons no crewed mission has returned to the Moon since the Apollo 17 mission in December of 1972. The author of this essay is Francis G. Graham, Professor Emeritus of Physics, Kent State University, and Founder of the American Lunar Society. Earlier in his career, he was a Planetarium and Observatory Lecturer 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.

             KOKH’S QUESTION: After 50 Years, Why No Lunar Settlements ?

By Francis G. Graham, Professor Emeritus of Physics, Kent State University

and Founder of the American Lunar Society

Reporting for Spacewatchtower

In the middle of the last century, not yet three fourths complete, human beings did an amazing thing.

They built several large chemical rockets and made a few trips to the Moon and back. The rocket type was the “Saturn V”, which had nothing to do with Saturn; it was a monster of a rocket, of which the preceding rockets were small by comparison. Yet this 360-foot-tall rocket and its associated technology was the minimum needed to accomplish the task with one rocket flight.

But since then, there have been no manned flights to the Moon. There have been no lunar settlements. To the bafflement of 1950’s science fiction writers, humans went to the Moon, and then stopped going there, or even anywhere else except Earth orbit. Prior to the 1960’s, except in the circles of such science fiction writers, talk of going to the Moon was crazy. So it was again in the 1990’s.

Which brings us to Kokh’s Question, named after Peter Kokh, an ardent lunar exploration activist, and founder of the Artemis Society.

.

The question is:“If lunar exploration began in the 1960s, why aren’t there lunar settlements now?”

Click on the Following Link To Continue Reading Professor Graham's Commentary ---

Link >>> http://buhlplanetarium2.tripod.com/weblog/grahamscorner/KOKHs_QUESTION.pdf

Internet Links to Additional Information ---

Apollo 11: Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2019.html#moonday

Personal Remembrance of Apollo 11 Mission by Glenn A. Walsh:
Link >>> http://buhlplanetarium2.tripod.com/bio/Apolloremembrance.htm

Related Blog Posts ---

"Pittsburgh Museum Displays Historic Apollo 11 Moon Mission Artifacts."

2018 October 24.

Link >>> http://spacewatchtower.blogspot.com/2018/10/pittsburgh-museum-displays-apollo-11.html

"Apollo 11 TV Camera Developer Dies at 91." 2015 Feb. 23.

Link >>> http://spacewatchtower.blogspot.com/2015/02/apollo-11-tv-camera-developer-dies-at-91.html

"45 Years Ago: Man Lands on the Moon !" 2014 July 20.

Link >>> https://spacewatchtower.blogspot.com/2014/07/45-years-ago-man-lands-on-moon.html

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

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

"Moon Day - A National Holiday ?" 2013 July 20.

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

 

"American Lunar Society Founder on 50th Anniversary: 1st Humans Orbit Moon, The Incredible Legacy of Apollo 8." 2018 December 24.

Link >>> http://spacewatchtower.blogspot.com/2018/12/50th-anniversary-incredible-legacy-of.html

 

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

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

Source: Francis G. Graham, Professor Emeritus of Physics, Kent State University & Founder of the American Lunar Society.

              Tuesday, 2019 July16.

                             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 >

Astro-Calendar: July / 50th Anniversary: Humans Land on Moon !

                        
This is a photograph of the boot-print on the lunar surface of Apollo 11 Lunar Module Pilot Buzz Aldrin, the second man to walk on the Moon 50 years ago this month. This particular boot-print was part of an experiment to test the properties of the lunar regolith. This boot-print occurred about an hour after he and Apollo 11 Commander Neil Armstrong set-foot on the Moon on Sunday Evening, 1969 July 20. This photograph has become one of the iconic images of this historic space mission.
More information: http://buhlplanetarium4.tripod.com/astrocalendar/2019.html#moonday
(Image Sources: NASA, Wikipedia.org, By NASA / Buzz Aldrin - This image or video was catalogued by NASA Headquarters of the United States National Aeronautics and Space Administration (NASA) under Photo ID: AS11-40-5877., Public Domain, https://commons.wikimedia.org/w/index.php?curid=468121)

Astronomical Calendar for 2019 July / 50th Anniversary: Humans Land on Moon ! ---
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2019.html#jul

 Related Blog Post ---

"Astro-Calendar: June / ISS Astronauts to Return June 24."

Sunday, 2019 June 2.

Link >>> https://spacewatchtower.blogspot.com/2019/06/astro-calendar-june-iss-astronauts-to.html

Source: Friends of the Zeiss.
              Monday, 2019 July 1.

                             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, 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 >

2019 Summer Begins at Moment of Solstice, Mid-Day

          

(Graphic Source: © Copyright 2005, Eric G. Canali, former Floor Operations Manager of 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) 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

This morning, Summer begins in the Northern Hemisphere of Earth, while at the same time, Winter begins in the Southern Hemisphere.

For 2019, the season of Summer begins at Earth's Northern Hemisphere's Summer Solstice (and the season of Winter begins at the Southern Hemisphere's Winter Solstice) at the moment of the June Solstice: Friday Morning, 2019 June 21 at 11:54 a.m. Eastern Daylight Saving Time (EDT) / 15:54 Coordinated Universal Time (UTC).

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 on one day of the year (in the Northern Hemisphere, on or near the day we now call June 21), the Sun would appear to stand-still as Sol reaches its highest 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, before appearing to reverse direction.

Although the Summer months in the Northern Hemisphere are known for the year's warmest weather, the Earth is actually at the point in its orbit farthest from the Sun (astronomically known as the point of aphelion) around July 5; the Earth's closest approach to the Sun (perihelion) each year is around January 2. Hence, in general, the distance from the Earth to the Sun is not the major factor determining the heat of Summer or the cold of Winter.

Solar radiation, and hence the heat from the Sun, 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.

While the Sun does have motions, it is actually the motion of the Earth tilted on its axis, away from the plane of the ecliptic (Earth's orbital plane around the Sun), while revolving around the Sun, that causes the Earth's seasons. As of the 2019 June Solstice, this tilt of Earth's axis is precisely 23.43676 degrees / 23 degrees, 26 minutes, 12.3 seconds. Hence, as the Earth arrives at the point in its orbit around the Sun, when the north polar axis is most directly inclined toward the Sun, this marks the Summer Solstice in the Northern Hemisphere and the Winter Solstice in the Southern Hemisphere.

Alternately, the Winter Solstice in the Northern Hemisphere (the Winter Solstice is always on or near December 21) occurs when the Earth reaches the point in its orbit when the North Pole is most directly inclined away from the Sun. And, conversely, at this time Summer begins in the planet's Southern Hemisphere.

For Earth observers at precisely 23.43676 degrees / 23 degrees, 26 minutes, 12.3 seconds North Latitude at the moment of June Solstice, the Sun will appear to shine directly overhead. The line around the Earth at 23.43676 degrees / 23 degrees, 26 minutes, 12.3 seconds North Latitude is known as the Tropic of Cancer. Likewise, at 23.43676 degrees / 23 degrees, 26 minutes, 12.3 seconds South Latitude is located the Tropic of Capricorn, where the Sun appears directly overhead at the moment of the December Solstice.

However, as the tilt of the Earth is dynamic, and changes minutely over the years, the location of the Tropic lines also change. Currently, these Tropic lines are moving north at the rate of 0.47 arc-seconds / 49.21 feet / 15 meters per year.

The names Tropic of Cancer and Tropic of Capricorn were coined in the last centuries B.C., when the Sun would appear in the Constellation Cancer the Crab on the June Solstice and in the Constellation Capricornus the Horned Goat on the December Solstice. However today, hours after the June Solstice, the Sun enters the Constellation Gemini the Twins, 30 degrees from Cancer. And at the December Solstice, the Sun is now in the Constellation Sagittarius the Archer.

This is due to “Precession of the Equinoxes” of Earth, which is analogous to the wobbling of a spinning top. In the case of the Earth, this 25,772-year wobble causes observers to view the Sun in different parts of the sky over the centuries, at the same time of year while remaining in the same geographical location. As the Earth wobbles over the centuries, the north pole star also changes. Currently, Polaris is our north pole star; around A.D. 13,700, Vega will be our north pole star, due to the Precession of the Equinoxes.

No matter which hemisphere, the day of the Summer Solstice always has the most hours and minutes of daylight (the length of time between sunrise and sunset) for the year, while the Winter Solstice always has the least number of hours and minutes of daylight for the year. The exact number of hours and minutes of daylight, for a particular location, depends on the locale's geographic latitude on the Earth. Astronomers and long-distance radio enthusiasts, both of whom mostly depend on non-daylight hours to ply their craft, often prefer the days closer to the Winter Solstice.

The Vernal Equinox, when the season of Spring begins in the Northern Hemisphere (and the season of Autumn begins in the Southern Hemisphere), occurs between the Winter and Summer Solstices when the Earth reaches the point in its orbit around the Sun when the Earth's axis is inclined neither toward nor away from the Sun. Likewise, when the Earth reaches the point in its orbit around the Sun, between the Summer and Winter Solstices, when the Earth's axis is inclined neither toward nor away from the Sun, this is known as the Autumnal Equinox (beginning of Fall or Autumn) in the Northern Hemisphere; at this time Spring begins in the Southern Hemisphere. And, half-way between the beginning points of each season are Cross-Quarter Days, each related to traditional holidays: Groundhog Day (February 2), May Day (May 1), Lammas Day (traditionally, the first harvest festival of the year on August 1), and Halloween (October 31).

In ancient times, the Summer Solstice was known as Mid-Summer Day, in early calendars observed around June 24. At that time, May 1 to August 1 (i.e. the two Cross-Quarter Days) was considered the season of Summer. Such early European celebrations were pre-Christian in origin. Many will associate this ancient holiday with the famous William Shakespeare play, “A Midsummer Night's Dream.” Some speculate that the play was written for the Queen of England, to celebrate the Feast Day of Saint John.

As with the Roman Catholic Church's decision to Christianize the pagan Winter Solstice festivals with the introduction of Christmas Day on December 25 (by an early calendar, December 25 was reckoned as the Winter Solstice), the Church began to associate the Mid-Summer festivals with the Nativity of Saint John the Baptist on June 24. In the Christian Bible, the Gospel of Saint Luke implies that Saint John was born six months before the birth of Jesus, although no specific birth dates are given.

The most famous celebration of the Summer Solstice occurs each year at the Stonehenge pre-historic monument in England. Constructed between 3,000 B.C. and 1,600 B.C. in three phases, the actual purpose of the landmark is still unclear. However, it seems to have been associated with burials, originally. It was also used as a type of astronomical observatory, particularly for observing the Sun, which was important to help early cultures make annual decisions regarding agriculture.

Stonehenge is known as a way for pre-historic peoples to mark both the Summer and Winter Solstices. From inside the monument, a viewer facing northeast can watch the Sun rise (weather-permitting) above a stone outside the main circle of rocks, known as the Heel Stone, on the day of the Summer Solstice in the Northern Hemisphere. Although today, due to serious erosion of the stones, visitors on the Summer Solstice can only walk around the landmark from a short distance away during this annual event.

Although not as prominent as Stonehenge, a calendar ring using smaller rocks was also constructed at Nabta Playa in southern Egypt, perhaps as early as 7,000 years ago! As with Stonehenge, some stones aligned with sunrise on the day of the Summer Solstice.

Today, a Stonehenge-like event occurs each year at the University of Wyoming (UW) Art Museum in Laramie, Wyoming, free-of-charge to the general public. At 12:00 Noon Mountain Daylight Saving Time (MDT) / 2:00 p.m. EDT / 18:00 UTC on the day of the Summer Solstice, visitors can see a single beam of sunlight shine through a solar tube in the ceiling of the UW Art Museum's Rotunda Gallery; the beam of sunlight then shines onto a 1923 Peace Silver Dollar embedded in the floor of the Museum's Rotunda Gallery. Visitors are encouraged to arrive at the museum by 11:30 a.m. MDT / 1:30 p.m. EDT / 17:30 UTC, to view this rather unique architectural feature.

The bright Star Spica (Alpha Virginis), the brightest star in the Constellation Virgo the Virgin and the 16^th brightest star in Earth's night sky (Apparent Visual Magnitude: + 0.97), may have helped develop another one of civilization's early calendars. A calendar of ancient Armenia used the year's first sighting of Spica in the dawn sky, a few days before the Summer Solstice, to mark the beginning of the New Year for this particular calendar. The development of this calendar somewhat coincided with the beginning of agriculture in Armenia.

Like clock-work, a well-known asterism (pattern of stars in the sky, not officially recognized as a constellation) of three stars shaped as a triangle is visible nearly overhead around local midnight during the Summer months (weather-permitting). And logically, as Star Trek's Mr. Spock might say, this asterism is known as the Summer Triangle!

Three of the brightest stars in the Summer sky constitute the Summer Triangle ---

1. Vega (Alpha Lyrae - brightest star in the Constellation Lyra the Harp); brightest of the three stars and closest to the zenith (highest point in the sky);
2. Altair (Alpha Aquilae - denotes the eagle eye and brightest star in the Constellation Aquila the Eagle); second brightest star of the trio;
3. Deneb (Alpha Cygni - denotes the tail star, is the brightest star in the Constellation Cygnus the Swan, and is the “head” star of the asterism known as the Northern Cross).

The term Summer Triangle was popularized in the 1950s by American author H.A. Rey and British astronomer Patrick Moore, although constellation guidebooks mention this triangle of stars as far back as 1913. And, during World War II, military navigators referred to this asterism as the “Navigator's Triangle.”

Regardless of city light pollution, the three bright stars of the Summer Triangle should be visible to nearly everyone in Earth's Northern Hemisphere (weather-permitting). So, just look overhead late-evening or early-morning throughout the Summer for these annual visitors to our Summer sky!

Internet Links to Additional Information ---

Summer Solstice: 
Link 1 >>> http://scienceworld.wolfram.com/astronomy/SummerSolstice.html 
Link 2 >>> http://en.wikipedia.org/wiki/Summer_solstice  

Season of Summer: Link >>> http://en.wikipedia.org/wiki/Summer  

History of Mid-Summer: Link >>> http://en.wikipedia.org/wiki/Midsummer
 
Summer "Solstice Day" Annual Free-of-Charge Day (With Snowballs !), 1985 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):  
Link >>> http://spacewatchtower.blogspot.com/2015/06/snowballs-on-first-day-of-summer.html

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

News Release - University of Wyoming Stonehenge-type event:
Link >>> https://www.uwyo.edu/uw/news/2018/06/uw-art-museum-to-celebrate-summer-solstice-june-21.html

Star Spica: Link >>> https://en.wikipedia.org/wiki/Spica

Precession of the Equinoxes: Link >>> https://en.wikipedia.org/wiki/Axial_precession 

Tropic of Cancer: Link >>> https://en.wikipedia.org/wiki/Tropic_of_Cancer 

Tropic of Capricorn: Link >>> https://en.wikipedia.org/wiki/Tropic_of_Capricorn 

Summer Triangle: Link >>> https://en.wikipedia.org/wiki/Summer_Triangle

Related Blog Posts ---

"Science Experiments Children & Teens Can Do At Home !" 2018 June 5.

Link >>> http://spacewatchtower.blogspot.com/2018/06/science-experiments-children-teens-can.html

 

"Snowballs on the First Day of Summer!" 2015 June 21.

Link >>> http://spacewatchtower.blogspot.com/2015/06/snowballs-on-first-day-of-summer.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Friday, 2019 June 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, 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 >

Requirement for World War II D-Day: Full Moon !

Spring Tides, the greatest tides of a lunar month, occur when the gravity of the Moon and the Sun are in direct alignment with the Earth, which occurs during Full Moon and New Moon phases of the Earth's Moon. Neap Tides, when the Sun's gravity partially cancels-out the gravitational pull of the Moon resulting in lower tides, occur during the Moon's First and Last Quarter phases. Spring Tides were a prerequisite for a successful D-Day invasion on 1944 June 6.
(Graphic Source: National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce)

By Glenn A. Walsh

Reporting for SpaceWatchtower

On Tuesday Morning, 1944 June 6, 75 years-ago today on a date known as “D-Day”, Allied Forces landed on the coast of Normandy in France, to begin the liberation of German-occupied France in Operation Overlord during World War II. The date of D-Day was no accident. The phase of the Moon was critical if D-Day was going to be a success!

Operation Overlord was actually the code-name for the entire Battle of Normandy. The Normandy Landings, commonly known as D-Day, was officially known as Operation Neptune, as it was to be the largest sea-borne invasion in history. In Roman mythology, Neptune was the god of the sea. Of course, Neptune also became the name of the eighth planet from the Sun, first observed by Johann Galle on 1846 September 23, from calculations developed by Urbain Le Verrier.

The D-Day invasion force consisted of 5,000 ships and landing craft carrying 130,000 soldiers across the English Channel from England to the Normandy beaches. More than a thousand air transports carried another 24,000 paratroopers and glider men, who landed in zones behind enemy lines. Just before sunrise, the Allied airplanes and ships started a constant bombardment on German strongholds along the coast. The nations participating in the D-Day invasion were the United States, Canada, Great Britain, Australia, Czechoslovakia, France, Norway, and Poland. 

Military planners set certain conditions for the Normandy invasion. First, it had to be a complete surprise to the Germans defending the French coast. Even though the Germans were expecting some type of invasion some day, they did not when or where it would occur.

In fact, U.S. General George S. Patton, who was well-respected by the German High Command, prepared a phantom army in eastern England for a supposed alternate invasion of France at Pas de Calais in Operation Fortitude. Through false intelligence leaks to German intelligence and deceptive military radio traffic (the 1944 version of “fake news”), as well as fictitious props and decoys to be observed by German air reconnaissance, German military planners were successfully convinced that the Allied invasion would occur at the narrowest section of the English Channel.

Also necessary for a successful invasion would be early morning time-of-day, reasonable weather and sea conditions, the lowest and then highest tides possible, and a Moon phase of Full Moon.

There are two reasons why the phase of the Moon was so important.

1. Spring Tides - Although D-Day occurred during the season of Spring, Spring Tides have nothing to do with the Spring season. Each day, the gravity of the Moon causes high and low tides along ocean coast-lines. Twice a month, at the Full Moon and New Moon phases of Earth's Moon, the Earth, Moon, and Sun are in a straight alignment known as a Syzygy. At this time, the gravity of the Sun reinforces the gravity of the Moon to provide the highest and lowest tides of the month; these are known as Spring Tides.
   Special Note: Summer in June of 1944 would not begin until Wednesday, 1944 June 21 at 13:02:45 Greenwich Mean Time (GMT - equivalent to today's Coordinated Universal Time) / 9:02:45 a.m. U.S. Eastern War Time (equivalent to today's Eastern Daylight Saving Time) / 3:02:45 p.m. British Double-Summer Time. During World War II, Great Britain advanced clocks two hours ahead of normal time (Greenwich Mean Time) during the warm-weather months, while America advanced clocks one hour ahead of Standard Time, called “War Time,” for the duration of the war. Allied Invasion Forces utilized British Double-Summer Time.
2. Full Moon - A Full Moon can provide illumination at night (after dusk) and early morning (before dawn), for areas where there is no artificial illumination, for aircraft pilots, glider pilots, and paratroopers.

The best tides were extremely important for the landing of troops on the Normandy beaches to be successful. Military planners needed the lowest tides possible at the beginning of the invasion near sunrise, while the highest tides possible during the actual ship landings later in the morning. During only a three-day period twice a month, when Spring Tides were available (during Full Moon and New Moon phases), could the needs of these military plans be satisfied.

Originally, U.S. General Dwight D. Eisenhower, Supreme Commander of the Expeditionary Forces in Europe, had planned to implement D-Day in May, but the invasion force was not ready. He decided that the invasion force would be ready by June 5, when Spring Tides and the Full Moon would be advantageous (even though Full Moon did not actually occur until June 6). However on June 4, British military weather forecasters advised him that high winds and heavy seas made a June 5 landing impossible. So, General Eisenhower reluctantly agreed to a 24-hour delay.

Had bad weather also prevented a June 6 landing in Normandy, the D-Day landings may have been postponed until the June 18 to 20 period of time (probably June 19) during the New Moon phase when Spring Tides would also be available. The New Moon phase occurred on Tuesday, 1944 June 20 at 17:00 Greenwich Mean Time (GMT) / 1:00 p.m. U.S. Eastern War Time / 7:00 p.m. British Double-Summer Time.

However, an invasion during the New Moon phase did have the major disadvantage of no illumination from the Moon during the early morning, pre-sunrise paratrooper and glider landings behind enemy lines. So, General Eisenhower really did want to execute D-Day on June 6, which would also maximize the number of fighting days on the European Continent during the warm-weather months.

A very low tide at the very beginning of the invasion would expose mined obstacles, such as stakes, ramps, tetrahedrons, hedgehogs, and Belgian Gates, all connected with barbed wire, which the Nazis had placed in the ocean near shore specifically to prevent invasion ships from landing. A very low tide would allow engineers in demolition parties to destroy these obstacles before the landing ships arrived.

Military planners also planned on having these demolitions executed during a rising tide. This was necessary since they needed the landing craft to land on the beach as soon as the obstacles were gone. And, the landing craft needed a high tide to land on the beach.

However, the engineers only had about a half-hour, between initial landings of the demolition crews (on June 6 at 4:30 Greenwich Mean Time / 12:30 a.m. U.S. Eastern War Time / 6:30 a.m. British Double-Summer Time) and the rising water level of the rising tide, to perform their demolitions. In the case of Omaha Beach, code name for one of two beaches where American troops landed, it was not enough time. The military planners had planned on the demolition crews providing 16 gaps in the Nazi's wall of obstacles; the engineers only had time to create 5 such gaps. This is why Omaha Beach is considered the bloodiest landing of the five beaches where troops landed.

American troops also landed at Utah Beach, while Canadian troops landed at Juno Beach. British troops landed at Gold and Sword Beaches.

A key part of the plan was to land troops behind enemy lines long before sunrise on D-Day, to capture or destroy rail and road bridges, secure control of causeways, and secure control of key roads and intersections. This was accomplished by U.S. and British Airborne Divisions through landings by paratroopers and glider men. Paratroopers and silent gliders started landing in Normandy on June 5 around 23:30 Greenwich Mean Time / 7:30 p.m. U.S. Eastern War Time / June 6, 1:30 a.m. British Double-Summer Time, following pathfinder paratroopers who had jumped about an hour earlier.

So, military planners considered it very important to have a bright Full Moon available to guide the Airborne Divisions to the drop-sites, and to guide the paratroopers and glider men to their landing sites. The time of the phase of Full Moon on D-Day (June 6) occurred at 18:58 Greenwich Mean Time / 2:58 p.m. U.S. Eastern War Time / 8:58 p.m. British Double-Summer Time.

Until recently, there was a mistaken belief that, to ensure darkness and complete surprise to Nazi troops as aircraft approached Normandy, military planners had planned on a late-rising Moon. In other words, the Moon would not rise, and create the needed night-time illumination, until after the aircraft had reached Normandy. This mistaken belief was promoted by a magazine article published in the Saturday Evening Post on 1946 June 8 by General Eisenhower's chief-of-staff during the war, General Walter Bedell Smith. In the article, General Smith wrote, “For the airborne landings … we needed a late-rising full Moon, so the pilots could approach their objectives in darkness, but have moonlight to pick out the drop zones.”

Early this month, in a Sky and Telescope Magazine on-line article, the record is corrected by Texas State University Professor Donald Olson. Citing astronomical calculations, Professor Olson found that the Moon actually rose about an hour and a-half before sunset on June 5 and remained in the sky the rest of the evening and the early morning of June 6 until around sunrise. Over Normandy, Moon-rise occurred on June 5 at 18:30 Greenwich Mean Time / 8:30 p.m. British Double-Summer Time, when the Moon was 99 per-cent illuminated by the Sun; sunset was June 5 at 20:01 Greenwich Mean Time / 10:01 p.m. British Double-Summer Time.

Local lunar transit, when the Moon reaches the highest point in the sky on a particular day, occurred over Normandy on June 5 at 23:19 Greenwich Mean Time / June 6 at 1:19 a.m. British Double-Summer Time. This was equivalent to June 5, 7:19 p.m. U.S. Eastern War Time, even though the Moon would not rise in America until later in the evening (Moon-rise in Pittsburgh was June 5, 7:40 p.m. U.S. Eastern War Time).

Actually, this is typical behavior of a Full Moon. Every month, on or near the day of Full Moon, the Moon rises around the time of sunset, stays visible in the sky providing the brightest Moon-light of the month (weather-permitting) all-night-long, and sets around the time of sunrise.

The success of D-Day was truly a team effort, and science and technology played a critical role in the Allied victory in Normandy. Astronomers, meteorologists, geologists, geographers, engineers, military planners, radio operators, aircraft pilots and crews, glider pilots, paratroopers, and combat field medics were an important part of the invasion, in addition to the thousands of soldiers, sailors, and Marines who landed on the beaches that historic day.

Internet Links to Additional Information ---

More detailed information on Astronomy, Tides, and the D-Day Landings from
Sky and Telescope Magazine:
Link >>> https://www.skyandtelescope.com/astronomy-news/astronomy-d-day-sun-moon-tides/

D-Day:
Link 1 >>> https://www.history.com/topics/world-war-ii/d-dayhttps://www.history.com/topics/world-war-ii/d-day
Link 2 >>> https://en.wikipedia.org/wiki/Normandy_landings

Full Moon: Link >>> https://en.wikipedia.org/wiki/Full_moon

Spring Tides: Link >>> https://en.wikipedia.org/wiki/Tide#Range_variation:_springs_and_neaps

Syzgy: Link >>> https://en.wikipedia.org/wiki/Syzygy_(astronomy)

Related Blog Posts ---

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

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

 

"WWII Medals Return to Earth in Time for Veterans' Day." Tue., 2014 Nov. 11.

Link >>> https://spacewatchtower.blogspot.com/2014/11/wwii-medals-return-to-earth-in-time-for.html

 

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Thursday, 2019 June 6.

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           More Astronomy & Science News - SpaceWatchtower Twitter Feed:
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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 >

Astro-Calendar: June / ISS Astronauts to Return June 24

International Space Station (ISS) Expedition 59 crew: (from left to right) astronauts David Saint-Jacques of the Canadian Space Agency and Anne McClain of NASA: cosmonauts Oleg Kononenko and Aleksey Ovchinin of Roscosmos; and NASA astronauts Nick Hague and Christina Koch. Crew members David Saint-Jacques, Anne McClain, and Oleg Kononenko are scheduled to return to Earth on June 24, using the Soyuz MS-11 spacecraft to land in Kazakhstan.
(Image Sources: NASA, Wikipedia.org, By NASA/Robert Markowitz - https://www.flickr.com/photos/nasa2explore/40055482243/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=76435324)
More on the ISS: Link >>> http://buhlplanetarium2.tripod.com/FAQ/sightopportun/ISS.html

Astronomical Calendar for 2019 June ---
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2019.html#jun

 Related Blog Post ---

"Astro-Calendar: May / NASA Planetary Defense Conference."

Monday, 2019 May 1.

Link >>> https://spacewatchtower.blogspot.com/2019/05/astro-calendar-may-nasa-planetary.html

Source: Friends of the Zeiss.
              Sunday, 2019 June 2.

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            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 >

New Era of Measurement: Kilogram Now Defined for All-Time

Replica of the International Prototype Kilogram (IPK) on display at the Museum of Science and Industry (Cité des Science et de l’Industrie) in Paris, France. The actual IPK served as the international standard for the kilogram from 1889 until the beginning of this week.
(Image Sources: Wikipedia.org, By Japs 88 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19652787)

By Glenn A. Walsh

Reporting for SpaceWatchtower

This week, weight measure moved from the 19^th century to the 21^st century. The official international measurement of weight or mass, the kilogram (kg), was redefined from a physical prototype to a fundamental physical property of the Universe.

The kilogram is the measurement of mass or weight, originally part of the Metric System now known as the International System of Units (SI). In the United States which uses Imperial Units, 1 pound is defined as 0.45359237 kilograms.

On World Metrology Day, Monday, 2019 May 20, scientists implemented the final conversion of a measure of the SI from a physical artifact to a mathematical equation of a universal constant.

From 1889 until this week, the kilogram was defined as the mass of the International Prototype Kilogram (IPK), a golf-ball sized object stored in a vault with six precise replicas at the International Bureau of Weights and Measures [or in French: Bureau International des Poids et Mesures (BIPM)], located in Saint-Cloud, France on the outskirts of Paris. Two additional precise replicas exist at the United States National Institute of Standards and Technology in Gaithersburg, Maryland, just outside of Washington DC. And, several other countries around the world also possess precise replicas.

As a measurement standard for each country, these replicas have been needed for science experiments that require very precise weight measurements and for international trade in items restricted by weight, including radioactive materials.

Manufactured as a right-circular cylinder, the IPK is composed of a platinum alloy known as "Pt 10Ir", which is 90% platinum and 10% iridium (by mass). The addition of 10% iridium greatly improved the hardness from the previous, all-plantinum kilogram definition artifact: the Kilogram of the Archives (Kilogramme des Archives), produced as a prototype in 1799. In 1875, when it was determined to make a new kilogram definition artifact, the Kilogram of the Archives was used to derive the IPK.

The decision to modernize the definition of the kilogram came last November 16 in Versailles, France, as scientists unanimously approved the change at a meeting of the General Conference on Weights and Measures. However, this decision was many years in-the-making, as scientists deliberated on how to solve a problem with the International Prototype Kilogram.

As an international standard, the International Prototype Kilogram (also known to scientists as the “Big K” or “Le Grand K") was meant to be unchanging, to ensure standardization throughout the international system of the measurement of mass or weight. But, with a physical artifact, this was not possible.

As any human-made object is imperfect, so was the International Prototype Kilogram. The IPK has lost 50 micrograms (about the weight of an eyelash) since it was created in 1889. And, replicas in each country, meant to be the standard for each country based on the IPK in Paris, may have lost more, less, or no micrograms. Hence, the IPK could no longer be a precise standard, nor could any of the replicas.

So, beginning this-past Monday, the kilogram is now defined by a concept from Quantum Mechanics: the Planck Constant, derived by German theoretical physicist Max Planck in 1900. Max Planck received the 1918 Nobel Prize in Physics "in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta".

The new definition of the kilogram is now determined to be the Planck constant, as defined by the ISO standard, set to 6.62607015×10⁻³⁴ J⋅s exactly. Ironically, the old kilogram (International Prototype Kilogram) was used to measure the value of the Planck Constant.

So, now the kilogram is defined by an unchanging standard “for all times, for all people.”

The original 1889 International Prototype Kilogram will now be displayed in a museum, instead of being securely hidden-away in a vault.

The kilogram was not the only SI standard redefined on May 20. New definitions for electric current, temperature, and the amount of a substance also changed. As with the kilogram, all of these new definitions are also related to constants of the physical Universe.

Internet Links to Additional Information ---

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

International Prototype Kilogram:
Link >>> https://en.wikipedia.org/wiki/International_prototype_kilogram

Planck Constant: Link >>> https://en.wikipedia.org/wiki/Planck_constant

International Bureau of Weights and Measures:
Link >>> https://en.wikipedia.org/wiki/International_Bureau_of_Weights_and_Measures

U.S. National Institute of Standards and Technology (previously, National Bureau of Standards):
Link 1 >>> https://www.nist.gov/
Link 2 >>> https://en.wikipedia.org/wiki/National_Institute_of_Standards_and_Technology

Related Blog Post ---

"Official Kilogram Standard Contaminated: Experiments Could be Affected.

The Kilogram Has Gained Weight." 2013 Jan. 6.

Link >>> https://spacewatchtower.blogspot.com/2013/01/official-kilogram-standard-contaminated.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Friday, 2019 May 24.

                             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 >