Gathering of Intelligence | Solvay 1927

I taught physics to high school students for my career. Names of important people in the history of physics, chemistry, and other sciences were always included in our textbooks and discussions. These people laid the foundation for what we believe today about how the world works.

In 1927, many of those individuals gathered for the Solvay Conference in Brussels. The colorized photograph below may have captured the most intelligence in one place and time the world has seen. Of the 29 attendees, 17 had won, or would go on to win, the Nobel Prize. Notable in the front row is the only woman at the conference, Marie Curie. She had won two Nobel Prizes in physics and in chemistry.

The primary mission of the conference was to discuss the impact of a new theory embraced by the man at the far right in the second row. The scientist Neils Bohr strongly supported the theory of quantum mechanics. He and Werner Heisenberg argued for what is called the Copenhagen Interpretation. In it, physical systems have a set of probabilities of outcomes if they are going to be measured. The act of measurement causes that set of possible probabilities to reduce to one outcome. Albert Einstein, center front row, did not like the idea of probabilities in nature. He said “God does not play dice”. Bohr replied “Einstein, stop telling God what to do”. Quantum mechanics is widely accepted today and is applied in many aspects of our lives.

The scientific contributions by each of the pictured individuals are described at this link. Scroll part way down that page to find them.



Ships Passing in the Night

It was 6:30 pm on 24 Jan 2018. The International Space Station was due to pass directly over our part of Iowa from WSW to NE. It was 3˚F outside with more than a foot of snow on the ground. Instead of going outside, I set the iPad in the bedroom window, closed the door, and recorded the pass for 6 minutes. While I watched the spaceship cruise above the trees at 5 mi/sec, an airship also cruised over at about 0.2 mi/sec. The stars silently observed from their perches. I stayed warm.

NightCap Camera | iPad2 | ISO=1536 | 356 sec | Click to embiggen

Morning Sun

I explained to my son how my shadow was cast almost straight down at noon when we were 12˚south of the equator in Peru. That had never happened to me before. Living 42˚north of the equator, we always cast shadows. They are short in the summer when the Sun is high in the sky and long in the winter when the Sun is low. But, never straight down like this.

My son posed a question about sunrises at the equator. “Does the Sun rise straight up due east each day of the year.” I said it doesn’t rise due east every day. But, it does rise nearly straight up. He acted skeptical. It was time to use desktop planetarium software to simulate the view.

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Fireballs Across the Sky

My great-grandparents were married in 1870. They farmed in west-central Illinois a mile from his brother. The brothers moved to Illinois from Ohio. Earlier, they moved to Ohio from Virginia during the Civil War. The rectangle in this 1941 aerial photo shows the location of the farmstead where my great-grandparents lived after they were married.


Here are my great-grandparents and their five children in about 1890. My grandfather is the one in the center back row.

Here is my great-grandfather’s brother and his wife. They eventually had seven children. Notice a date of Oct 74 at the bottom. That is when a relative photographed the original photo from nearly 100 years before.


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DAWN Spacecraft | End of Mission

NASA’s DAWN spacecraft ran out of fuel used to point its antenna toward Earth. Communications failed on 31 Oct and 1 Nov 2018. It was launched in 2007 to study minor-planets Vesta and Ceres, the two largest asteroid bodies in our solar system. It achieved the mission goals which I have highlighted in several previous posts. NASA issued this press release about the DAWN mission which I encourage you to read.

DAWN was the first spacecraft to fly to a body of the solar system, descend into orbit, conduct science, ascend from orbit, travel to a second body, descend into orbit, conduct science, and all under the propulsive power of an ion engine instead of a chemical rocket engine.

Chief Engineer and Mission Director Mark Rayman reflects on the mission in this video.


ISS Passed by Saturn and Mars

The International Space Station approached from the northwest at 9 pm on 8 Aug 2018. It went high overhead in a southeasterly direction. It tracked above Saturn and the Teapot in Sagittarius before disappearing near Mars. There it entered the darkness of Earth’s shadow.

Taken on iPad with NightCap | ISS mode | 189 sec exp

Here is the same image annotated. Can you also see the light trails left by two passing jets? Tap images for more detailed views.

Looking SE at 9 pm