American Scientist

The Many Sides of Science

To the Editors:

It struck me that two adjacent articles in the March–April issue show a strong contrast in their approaches to doing science. Robert Pennock’s “The Call of Science” (Science and Engineering Values) highlights the essential role of evidence, while also mentioning the importance of honesty, objectivity, perseverance, and humility. Caryn Babaian, on the other hand, emphasizes the roles that visualization, imagination, and artistic creativity play in scientific discovery and understanding in her article, “Deconstructing DNA Beyond the Helix.”

What a rich ferment of talents comes to the fore to produce this magnificent edifice we call science! May each of us bring our strengths and contribute our gifts to this process of generating knowledge and understanding. Spoudon xynones indeed!

I did notice that Babaian indicated in her article that Rosalind Franklin’s crystallographic results were obtained using electrons, whereas I believe she meant to write x-rays, or perhaps photons.

E. Michael Attas
Pinawa, Manitoba, Canada

Dr. Babaian responds:

The atoms of the DNA fiber contain electrons that diffract x-rays; the beam directed at them is described as either photons or x-rays.

Sometimes people describe x-rays as a stream of electrons because x-rays are produced in a cathode-ray tube, but “photons” is used more frequently.

An x-ray is a packet of electromagnetic energy (photon) that originates from an electron cloud of an atom. So most accurately, the image was obtained using photons emitted from electron clouds.

To the Editors:

As I was paging through the March–April issue of American Scientist, I was astounded to see in Bhimsen Shivamoggi’s article “Gas Dynamics of Solar and Stellar Winds” an image of the star LL Ori colliding with gas to create a “bow shock” effect (above).

As a young postdoc trying out the new camera on the Mayall 4-Meter Telescope at Kitt Peak National Observatory in Arizona, I tested some large-format interference filters on the Orion Nebula. A few days later, having copied the imagery and printed it on a large print, I noticed a faint curved structure around one of the minor stars in the nebula. Additionally, I could pick out several bubbles surrounding other stars.

A few months later, I had begun a survey of the Milky Way searching for faint nebular structures. I noticed another partial shock associated with Zeta Ophiuchi, a single star located in the constellation of Ophiuchus. Several of us completed that survey that extends around the entire Milky Way in a 14-degree-wide band.

A few years later, I had moved to Goddard Space Flight Center in Maryland where I met Sabatino Sofia, one of the foremost astronomers on the structure of the Sun. In a conversation one day, I showed him several prints, which led to a the first observational paper on distorted interstellar bubbles. Later, we published a number of papers describing the effects of early star associates that create superbubbles. And after that, astronomers using the Hubble Space Telescope produced the image that you included in your article.

Theodore R. Gull
Emeritus Astronomer
NASA Goddard Space Flight Center

Gibbs’s Legacy

To the Editors:

I read with great pleasure Lee S. Langston’s wonderful article on J. Willard Gibbs (“The American Inventor of Modern Thermodynamics,” Technologue, March–April 2024). I taught at Yale University for 14 years and heard many tales about Gibbs. In one story, Michael Faraday came to visit Yale. He was greeted at the train station by the governor of New Jersey, the president of Yale, and other dignitaries. He went down the line shaking hands, and when he came to the end he exclaimed, “Where is Gibbs?” Well, of course, no one in the line even knew who Gibbs was.

Ted W. Reid
Lubbock, TX