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Adventures In Time And Space 5: Cinder Lake Crater Fields

 Crater field #1 was designed to simulate Apollo 11 landing site taken from Lunar Orbiter images

Crater field #1 (above) was designed to simulate Apollo 11 landing site taken from Lunar Orbiter images (below)

The San Francisco Volcanic Field is located on the Colorado Plateau in northern Arizona. The major stratovolcano in the volcanic field is San Francisco Mountain. Cinder debris, black pea-sized frothy lava from these once-active volcanoes, covered the surrounding sedimentary rock surface during the Quaternary period.

In the 1960s, NASA wanted to train the astronauts in geology. The Astrogeology branch of the United States Geological Survey (USGS) in Flagstaff chose northern Arizona because its geological formations were thought to be similar to those on the moon. The Cinder Lake crater field was specifically chosen for the creation of a realistic lunar-like landscape.

In 1967, NASA completed the first phase of its lunar analog crater field with a 500 square-foot area designed to duplicate a section of Mare Tranquillitatis, a potential Apollo 11 lunar landing site that was captured in images from Lunar Orbiter II. The Cinder Lake field initially contained 47 craters with diameters of 5 to 40 feet. It was expanded later that year to an 800 square-foot field with 143 craters total. Over 300 pounds of dynamite and over 13,000 pounds of ammonium nitrate were used to blast the craters from the black lightweight cinder debris.

Cinder Lake Crater Field #1 was used to help train astronauts on identifying craters and on determining their location in a lunar landscape. The astronauts also practiced using geologic hand tools and testing scientific experiment packages and various lunar vehicle prototypes. A simulated Apollo lunar module ascent stage was also constructed and placed on a ramp to give it the appropriate height off the lunar analog surface.

In the second phase, NASA decided to build a larger 1,200 square-foot test field with 354 craters just north of Cinder Lake Crater Field #1. The new location was selected because the dark basaltic cinder over there covered the lighter clay beds, so that blasting craters would create distinctive light-colored ejecta, including crater rays.

Crater field was used to create Apollo 11 EVA planning map

Crater field was used to create Apollo 11 EVA planning map (simulated LM on ramp center left)

Final crater field contained 143 craters (simulated Lunar Module on ramp)

Final crater field contained 143 craters (simulated Lunar Module on ramp)

 Crater field #1 was used also to test Explorer vehicle prototype

Crater field #1 was used also to test Explorer vehicle prototype

The Pencil: History Of Design And Circumstance

Henry Petroski, the Aleksandar S. Vesic Professor of Civil Engineering and a professor of history at Duke University, traces the origins of the pencil by starting with the writing technologies of ancient Greece and Rome, continuing in the 1500s with the discovery of the mineral graphite, and goes through the Industrial Revolution with the development of mass production. He discusses how Henry David Thoreau worked in his father’s pencil factory, inventing techniques for grinding graphite powder and blending different mixtures of graphite, clay, and other substances to produce pencils with varying qualities of darkness and hardness. Petroski shares with us what the common pencil can teach us about design, engineering, and technology.

What Is A Number 2 Pencil?

Why do they always insist on you using a number 2 pencil?

scantron

Most modern pencils have a core made of a mixture of graphite and clay. The word pencil comes from the Latin word penicillus, meaning a little tail. In the 1500s, it was called plumbago, Latin for lead ore, because it was thought to be a form of lead. Consequently, the pencil core is still referred to as pencil lead, even though it never contained the element lead. Ironically, until about a half century ago, lead poisoning from pencils was possible due to the use of lead paint for the outer coat. This paint then could be ingested when the pencil was bitten or chewed.

Graphite is a mineral that is an allotrope of carbon (on the right, below). Allotropes are pure forms of an element that differ in structure. Graphite is carbon laid out in slippery sheets. Diamond (on the left, below) is carbon bonded into a rigid structure. Graphite was named in 1789 by Abraham Werner from the Greek word grapho, meaning to draw or to write. Unlike diamond, graphite is a conductor of electricity. Because of this property, it is useful as electrodes in arc lamps and batteries.

allotropes carbon

The development of the modern pencil started in the 16th century, when a large deposit of graphite was discovered in England that was very pure and solid enough to be cut into sticks and used for marking sheep. But because graphite is soft, the graphite sticks were wrapped in sheepskin or string for neatness and to prevent them from breaking apart. Shortly afterward, an Italian couple named Bernacotti, in an effort to improve the overall design, had started hollowing out sticks of wood and inserting graphite sticks into them. In 1795, Nicholas Conté discovered a procedure of mixing powdered graphite with clay to form rods that were then baked in a kiln. Conté discovered that by changing the ratio of graphite to clay, he could change the hardness of the pencil rod. The greater the amount of graphite, the softer the rod and the darker the pencil mark as it deposits more graphite onto the paper. The greater the clay, the harder the rod, the lighter the mark.

Conté created a numbering system for grading pencil hardness. He started at 1 and higher numbers indicated softer rods. Incidentally, this procedure of mixing graphite and clay was developed independently in the US in the 1800s by the father of Henry Thoreau, John Thoreau. His grading system, however, used higher numbers to designate, instead, harder rods. This 1-4 numbering system by Thoreau is still used in the US today. For the rest of the world, most of the pencils are graded on the European HB system developed in the early 20th century by Brookman, an English pencil maker. It allows for a greater selection of graphite-to-clay ratios by using a continuum from H (for hardness, or increasing clay) to B (for blackness, or increasing graphite).

pencil grades

If we translate the Thoreau numbering system to the European HB system, it is as follows:

1 = B          2 = HB          2.5 = F          3 = H          4 = 2H

The grade HB is at the middle of this continuum, offering a balance between erasability (graphite) and durability (clay). You want a pencil mark to be reasonably easy to erase without ripping a hole in the paper, but not so soft and dark that it smudges all over. Consequently, the standard writing pencil is graded HB… or… wait for it… number 2.

Nobel Prize 2008

"Prizes to those who, during the preceding year, shall have conferred the greatest benefit to mankind."

“Prizes to those who, during the preceding year, shall have conferred the greatest benefit to mankind.”

The 2008 Nobel Prize awards for chemistry, physiology or medicine, and physics were recently announced as they are every year at around this time.

As I mentioned in last year’s post, the Nobel Prize awards were established in 1895 according to the will of Swedish chemist, engineer, and inventor Alfred Nobel and endowed by his estate. Other than the three natural science awards, Alfred also wanted awards for literature and peace. All five Nobel Prizes were first awarded in 1901. In 1968, Sweden’s central bank established and endowed the Nobel Memorial Prize in Economic Sciences for their 300th anniversary. This prize for economics in honor of Alfred Nobel was first awarded the following year.

The Royal Swedish Academy of Sciences grants the prizes for chemistry and physics (and economics), while the Karolinska Institute grants the prize for physiology or medicine.

The Nobel Prize awards are presented in Stockholm, Sweden (except for the Nobel Peace Prize, which is presented in Oslo, Norway) every year on December 10, which is the anniversary of Alfred Nobel’s death.

The Nobel Prize science medals were designed by Swedish engraver Erik Lindberg in 1902. The Latin inscription on the medals is

Inventas vitam juvat excoluisse per artes

and can be translated as And all who found new arts, to make man’s life more blest or fair. The inscription is from Book 6, line 663 of Vergil’s Aeneid:

And poets, of whom the true-inspired song deserved Apollo’s name;
and all who found new arts, to make man’s life more blest or fair;
(translation by Theodore C. Williams)

For the chemistry and physics medals, Erik Lindberg chose to show Nature being unveiled by the Genius of Science. For the medal for physiology or medicine, Erik chose to show the Genius of Medicine gathering water to quench the thirst of a sick child.

"And all who found new arts, to make man's life more blest or fair"

Chemistry: Genius of Science unveiling Nature

The 2008 Nobel Prize for Chemistry is awarded to Boston University Medical School scientist Osamu Shimomura, Columbia University scientist Martin Chalfie, and Howard Hughes Medical Institute scientist Roger Tsien for their discovery and development of the green fluorescent protein (GFP).

"And all who found new arts, to make man's life more blest or fair"

Physiology or Medicine: Genius of Medicine quenching the thirst of the Ill

The 2008 Nobel Prize for Physiology or Medicine is awarded to German Cancer Research Center at Heidelberg scientist Harald zur Hausen for his discovery that human papilloma viruses cause cervical cancer.

"And all who found new arts, to make man's life more blest or fair"

Physics: Genius of Science unveiling Nature

The 2008 Nobel Prize for Physics is awarded for two discoveries: for Enrico Fermi Institute scientist Yoichiro Nambu and his discovery of the mechanism of spontaneous broken symmetry in subatomic physics and for High Energy Accelerator Research Organization (KEK) scientist Makoto Kobayashi and Yukawa Institute for Theoretical Physics (YITP) scientist Toshihide Maskawa and their discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature.

Adventures In Time And Space 4: Royal Observatory At Greenwich

The Prime Meridian near Flamsteed House

The Prime Meridian near Flamsteed House

The Royal Observatory at Greenwich is on a hill in Greenwich Park in London and is the location of the Prime Meridian. The observatory was commissioned in 1675 by King Charles II for the purposes of celestial navigation and cartography. The king appointed John Flamsteed as the first Astronomer Royal to serve as the director of the new observatory.

The Prime Meridian passes through the Greenwich Observatory complex and is marked by a stainless steel strip in the courtyard. In recent times, a green laser also marks the location and shines across the night sky. The Prime Meridian is part of a geographic coordinate system. This coordinate system is useful for making maps because every location on Earth can be identified by its latitude and longitude.

The latitude is an angular measurement ranging from 0° at the Earth’s equator to either +90° at the north pole or −90° at the south pole. Lines of latitude are circles of differing circumferences on the Earth’s surface. The largest circle is called a great circle and it is the equator. Lines of latitude also are called parallels because the circles are parallel to each other. The equator divides the Earth into the Northern Hemisphere and the Southern Hemisphere. On the Earth’s surface, each degree of latitude corresponds to a distance of about 111 kilometers.

The longitude is an angular measurement ranging from 0° at the prime meridian to either +180° eastward or −180° westward. All meridians are halves of great circles which converge at the north and south poles. The prime meridian and its opposite, the 180th meridian at 180° longitude, together form a great circle around the sphere of the Earth and divides it into the Eastern Hemisphere and the Western Hemisphere. Because lines of longitude converge at the poles, each degree of longitude corresponds to a different distance on the Earth’s surface as the latitude changes. At the equator, the distance is about 111 kilometers, but this distance gets smaller until it reaches 0 kilometers at the poles.

For further precision, each degree of latitude and longitude (°) is divided into 60 minutes (‘), each of which is further divided into 60 seconds (”), e.g., San Antonio, Texas is located at 29°25′26″ N and 98° 29′ 37″ W. These coordinates also can be expressed as decimal fractions, e.g., San Antonio is 29.42412 and -98.49363.

Unlike the equator, which is the one great circle perpendicular to the Earth’s axis of rotation, the location of the prime meridian is arbitrary, and can be part of any great circle that runs through both poles. Throughout history, it was common practice to choose a nation’s capital or some other popular location, so different maps had different prime meridians. Finally, it was decided in 1884 to have delegates from 25 nations meet in Washington, DC, for the International Meridian Conference. The delegates voted to adopt Greenwich as the location for the universal Prime Meridian.

Map of the Prime Meridian at the Royal Observatory Greenwich (south is up)

Map of the Prime Meridian at the Royal Observatory Greenwich (south is up)

Once Greenwich was chosen as the universal Prime Meridian, the longitude at any location can be determined by calculating the time difference between that location and Greenwich. Since a day has 24 hours and a circle has 360°, then the sun moves across the sky at a rate of 15° per hour. As a simple example, if a location is six hours behind the time at Greenwich, then that location is near 90° west longitude. Obviously, a chronometer set to Greenwich time and the local time need to be known.

GPS shows 0.00149 degrees (about 5.3 seconds) due to IERS Meridian being about 100 meters eastward

GPS shows 0.00149 degrees (about 5.3 seconds) due to IERS Meridian being about 100 meters eastward

So why doesn’t the Greenwich Prime Meridian show 0° longitude? The reason has to do with the fact that the Earth is not really a perfect sphere and that, until recently, most maps had to shift their lines of latitude and longitude until they matched local surface measurements to some reasonable amount.

It was only until the existence of artificial satellites that maps finally could be adjusted to the center of the Earth’s mass and not to various local surfaces. The current coordinate system, the World Geodetic System, was established in 1984 (WGS 84) and measures global surface locations to within ±1 meter or better. WGS 84 showed that the Greenwich Prime Meridian was actually about 5.3 seconds or about 100 meters west of 0° longitude. The new meridian is known as the International Reference Meridian and is maintained by the International Earth Rotation and Reference Systems Service (IERS). It is the reference meridian of the Global Positioning System (GPS) run by the United States Department of Defense.

The IERS Reference Meridian is about 5.3 seconds (about 100 meters) east of the Greenwich Meridian

The IERS Reference Meridian is about 5.3 seconds (about 100 meters) east of the Greenwich Meridian