Friday, May 24, 2019

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 19th century to the 21st 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 >

Wednesday, May 15, 2019

Tell NASA Your, or Your Family's, Apollo 11 Moon Landing Memories: Oral History Project


                    Iconic photograph of Buzz Aldren, the second man to walk on the Moon.
                                                                 (Image Source: NASA)

By Glenn A. Walsh
Reporting for SpaceWatchtower

July 20 marks the 50th anniversary of the first landing of human beings on another planetary body, the Earth's Moon. For those of you who were alive back then and observed this historic event, NASA wants to hear from you---or, if you were too young to remember this event, perhaps you can send an interview of a family member who did experience the excitement of watching history-in-the-making!

NASA is starting an Oral History Project seeking vocal comments from Americans who observed the first steps of American astronauts on the Moon, which culminated the 1960s Space Race in which the United States beat Russia to the Moon. This Oral History Project will continue for the rest of the year, with submission recordings due by 2019 December 31.

However, for those who can submit their recorded comments before June 14, those comments may be included in NASA Explorers: Apollo, a special NASA “commemorative audio series that examines the Moon’s cultural and scientific influence over the last half century, while also peering into the future of planetary exploration.”

For those of you too young to remember the Apollo Moon Landings, you can still participate in this project. Perhaps your parents, grandparents, or other relatives or friends remember this historic event. You could interview them and send that recording or recordings to NASA.

All of these recorded comments and interviews will be archived as part of the NASA Explorers: Apollo Oral History Project. And, NASA will use some of these recordings for the commemorative audio series, posted on the NASA web-site, and posted on NASA's social media platforms.

Send the completed recording(s) to the following e-mail address:

                                                apollostories@mail.nasa.gov

The following are guidelines and suggestions from NASA for completing the recordings and submitting your stories to NASA ---

How to record and submit your story

The deadline to submit your story to the Oral History Project is 2019 December 31. However, submissions received before 2019 June 14 will have the best chance at being featured within the audio series.
  1. Open the voice recording app on your mobile device. If you don’t have one, there are several free options you can download from your preferred app store.
  2. Record your story or interview. Try to follow the recording tips and guidelines below.
  3. Email your audio file to apollostories@mail.nasa.gov. In the text of your email, include your full name, your hometown and state. If you interviewed someone, please include their full name and hometown as well. Include any information you think helps give context to your story. (“I interviewed my grandma. She was 15 years old when the astronauts landed on the Moon …”).
  4. Keep an eye on your in-box. You’ll receive a thank-you email from us and we may follow up to get more detail or clarify something in your story.

Recording tips and guidelines

  • Try to keep your answers to each question under 120 seconds. Shorter stories will have a greater chance of being featured within NASA’s Apollo audio series, but longer stories may still be featured on nasa.gov or social media as a part of the Oral History Project. 
  • Start the recording by introducing yourself and telling us where you’re from. If you’re interviewing someone, do the same for them. We want to give you credit for the story!
  • Hold the recording device at least 6 inches from your face, or simply place it on a table in front of you or between you and the person you’re interviewing.
  • Allow for a natural pause between questions and answers.
  • Preferred audio file formats are .mp3, .mp4, .m4a or .wav.
Suggested questions to answer yourself or ask your interviewee
  • What does exploration mean to you?
  • What do you think it would be like to see humans walk on the Moon again?
  • When you think of the Moon, what comes to mind?
  • What do you want to know about the Moon?
If you remember the Apollo program ...
  • Where were you when humans walked on the Moon for the first time? Describe who you were with, what you were thinking, the atmosphere and how you were feeling.
  • What was your life like in 1969?
  • Do you remember learning about space in school? If so, what do you remember? 


Special Thanks: James J. Mullaney, former Curator of Exhibits and Astronomy at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.

Internet Links to Additional Information ---

NASA News Release: "Share Your Apollo Story with NASA."
Link >>> https://www.nasa.gov/apollostories

Apollo 11 ---
Link 1 >>> https://www.nasa.gov/mission_pages/apollo/missions/apollo11.html
Link 2 >>> https://www.nasa.gov/mission_pages/apollo/apollo-11.html
Link 3 >>> https://www.nasa.gov/apollo11-gallery
Link 4 >>> https://en.wikipedia.org/wiki/Apollo_11

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Wednesday, 2019 May 15.

                             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, May 1, 2019

Astro-Calendar: May / NASA Planetary Defense Conference

                                                     
Image of one full rotation of the Asteroid Bennu, as seen from NASA's OSIRIS-REx space probe, which is now studying Bennu and is expected to return to Earth a sample of the asteroid on 2023 September 24. This week (2019 April 29 to May 3), the bi-annual Planetary Defense Conference (regarding defense against asteroid strikes), sponsored by the International Academy of Astronautics, is being held in suburban Washington DC. More information: Link >>> http://pdc.iaaweb.org/
(Image Source: NASA)

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

 Related Blog Post ---

"Astro-Calendar: April / Possible GPS Date & Time Problem April 6."

Monday, 2019 April. 1.

Link >>> https://spacewatchtower.blogspot.com/2019/04/astro-calendar-april-possible-gps-date.html


Source: Friends of the Zeiss.
              Wednesday, 2019 May 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 >