Stars in our eyes


One of the most joyous scientific accomplishments of 2022 was the launch and deployment of the James Webb Space Telescope. The resulting images, glorious unto themselves, reveal new discoveries, new objects of research.

The human instinct for exploration has been unleashed and the possibilities seem endless.

For many years, the Hubble Space Telescope has provided one fantastic image after another of planets, stars, and galaxies. Almost immediately after images from the Webb Telescope started to appear, observers wanted to compare the output of Webb and Hubble. The two pictures below (Hubble on top, Webb on the bottom) are deep-field images revealing thousands of galaxies. You can see the detail in the Webb image far exceeds the Hubble.

Hubble Telescope Image

Hubble Telescope Image (Credit: NASA, ESA.)

Recently, I was looking through the 1895 book The Stars, by George F. Chambers. In one chapter, he focuses on counting the stars in “the galaxy,” a term he used to encompass the Milky Way. There was no recognition that other galaxies even existed. What came to be known as the Andromeda Galaxy was still thought to be a gaseous cloud (nebula) in our galaxy.

That 1895 book went on to discuss “the facts” of astronomy. Those “facts” would change many times in the following decades.

Human essence

It is intrinsic to human nature that we explore — and that we get excited about our discoveries.

For centuries, scientists have been perfecting more powerful telescopes and microscopes that allow us to see farther and with more focus. The pursuit of better “seeing” is rarely questioned.  Not only does it appeal to our exploration genes, it plays to the tremendous value we assign to our sense of sight.

Webb Telescope Image

Webb Telescope Image (Credit: NASA, ESA, and CSA)

The appeal of looking at new, unseen places is powerful. It is exciting to look deeper into the universe or to take pictures of mountains on Pluto, which not long ago had been a dot that you might be able to see if you knew exactly where and when to look.

Every new close-up of Jupiter and its moons delivers previously unseen worlds that are different from Earth, often in unexpected ways.

At some level, when we are looking at places that we have never looked at before, it is “easy science.” We see something new and different. We start to describe the phenomena with our laws of physics, chemistry, and biology. We use this qualitative research and, perhaps, other more quantitative data of an object’s characteristics to advance and test our understanding of the natural world.

With such observations, we are expanding our experience of nature in easy, intuitive ways.

Mission to Planet Earth

I worked at NASA for more than 25 years before coming to the University of Michigan.

It was understood — as part of the job — that missions to other planets were more exciting and engaging than missions to observe Earth. Those missions were not as encumbered by politics as Earth science missions.

Telescopes that flew in space and looked outwards were well received. Telescopes that looked at the Earth were deemed political fodder and mockingly called “GoreSat.”

Hubble and Webb Telescopes would discover new worlds. Earth science satellites would measure rain.

At one point in my time at NASA, I tried to frame the ease of planetary science versus the torment of Earth science. Using a telescope to observe new places was fundamentally exciting, especially to the people who appropriate money to federal agencies.

I also maintained that, compared to Earth, these regions were data-poor. This lack of data made scientific investigation relatively smooth. Obviously, the more observations and analysis one has recorded, the more contradictions one is likely to find.

Scientists have a far more difficult time developing a tidy consistent story for the Earth-bound sciences when dealing with centuries of quantitative research.

For a while, NASA used the name “Mission to Planet Earth” to convey the same sense of exploration and discovery that the astronomy and planetary missions enjoyed. But the outward-looking culture of NASA was deeply entrenched. During the design phase of one mission, I remember seeing an animated mockup of how a suite of instruments would work in concert. After watching the animation for a while, one of the people in the room said it was very pretty, but the instruments should be looking down at Earth, not outwards to space.

But isn’t Earth more important?

As Earth scientists at NASA, we had to answer the questions: “So what? Exactly how was this mission going to benefit humans, the economy, and society?” Space and astronomy missions didn’t seem to face the same questions.

The Earth science missions were profoundly important to the well-being of humans and our ecosystems. They were important to the health and safety of the planet. One would think that would ensure support for our work.

But it was never enough just to learn something new: How was it going to reduce uncertainty? (It would not.) How would it benefit policy? When would there be an end to these missions? Hadn’t we learned enough — all that was worth knowing — about planet Earth?

On closer examination, the looming issue of “regulation” is firmly planted at the foundation of all these questions. Imagine if scientific observations revealed damage to Earth, and were used to shape federal policy and other regulatory actions. How does this research, for example, influence behavior at the Environmental Protection Agency?

This is a classic situation where resistance outshines understanding. Ironically, it is because of that profound importance to the well-being of humans and our ecosystems that Earth science is political and controversial. It is not benign discovery. At the same time, planetary and astronomy missions often are justified as relevant to “understanding Earth” and life on Earth.

The value of context

I think it is important to understand the underlying subtext at work here.

We have come a long way in our observations, understanding, and predictions about Earth. Many countries beyond the U.S. have embraced and diversified scientific exploration and observation.

This diversification includes nations that hold radically different perspectives on environmental security and economics. We are not hostage to U.S. political whims, and enjoy the benefit of global perspectives.

There is, however, a fundamental underlying aspect of Earth observations.

Though they might provide fundamental, exciting discoveries for scientists on the ground, they do not promise the undeniable appeal of observing thousands of never-before-seen  galaxies or the actual surface of a comet. Earth observations provide important and continuing data in an already seemingly data-rich field. But the problems are much harder now and more data is needed to answer some urgent questions: How fast will the ice melt? Can we stop it? What will we do about it?

The Earth observations have provided knowledge of what we are doing to the planet and how we can behave to benefit our future. They tell us the hard work we will need to do to ensure a secure environment.

(Lead image: Construction of the Detroit Observatory at U-M. Image courtesy of U-M’s Bentley Historical Library.)


  1. John Snell - 1970-74

    Many thanks for this Ricky. Many good issues raised, especially that of the subtext! We even now often see the Blue Marble with other than North America front and center. I wish I could have heard you and your brother discussing the topic of looking up/looking down!


    • Richard Rood

      Thanks John,

      For those who don’t know, my (late) brother was an astrophysicist.

      The last real conversation I had with him was hilarious, and included him describing to his Freshman PE teacher at NCSU that what he was being asked to do was physically, in the sense of physics, impossible.


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