On Earth we are now considered to be in a new epoch, the Anthropocene, in which humankind has become a leading order influence on the planet—in effect, turning Earth into a slightly different planet. In the new era of exoplanet science, formerly uncertain terms in the Drake equation such as the fraction of stars with planets are now observationally constrained—for example, most stars have planets! One of the biggest remaining uncertainties in the equation is the average lifetime of a technological civilization before it destroys itself or consumes all its energy sources.

This is what thinking about other planets in addition to the Earth does. It takes one from wondering what the impacts of anthropogenic greenhouse gas increases will do to sea level, to extreme temperatures, to hurricane intensities, to regional drought in our lifetimes, and ups the ante to the larger question of whether in the long run our civilization will eventually figure things out and learn to sustain itself, or perish.

As I near the end of my career, this opportunity to reflect upon it has made me more aware of lessons I have learned (mostly unintentionally) along the way:

1.) Serendipity can have a great deal to do with the progression of a career.

Many of us may have agonized about the direction we should follow in our careers when we were in school—I certainly did. My career has been anything but a straight line determined by my initial choices. Rather, it has been defined by a combination of failures, being in the right place at the right time, and openness to go in new directions. I have experienced one of the most remarkable periods in the history of science. I entered science about a decade after launch of the first Earth‐orbiting weather satellites and the first successful spacecraft missions to other planets, and I have witnessed visits to every planet in the solar system. I have been in science during the period of humanity’s awakening about anthropogenic climate change (unfortunate for humanity but a tremendous stimulus for more deeply understanding our own planet). Finally, I have seen the universe unveiled as the home of thousands (at least) of known planets orbiting other stars, and I was able to be a contributor to one of the earliest groups thinking about how to determine which of these might be good candidates to harbor life. My career has clearly been shaped by these external events.

2,) Science is usually a team sport.

The media tend to portray science using the paradigm of the heroic lone scientist, usually out in the field, gathering data, and experiencing that “eureka!” moment that immediately overturns an existing science paradigm. Perhaps that is sometimes true, but it has not been my own experience. Almost all my published papers were joint efforts with colleagues whose technical expertise and scientific insight complement my own. I hope that this essay is a suitable way to express my gratitude for how I have benefited from their talents. Some of my papers arose from data collected (by others) during field experiments, but most were modeling, theory, or remote sensing data analyses. And in fields as complex as the climates of Earth and other planets, paradigm overturning is usually a slow motion process—several of my more successful papers have been more highly cited in recent years than in the years that followed their publication.

3.) Cross‐discipline research has made me a better scientist.

I am often asked, “How does studying other planets help you understand Earth?” Although there are a few examples (Kahn, 1989), in general, the best way to understand Earth is to study Earth. The real value of studying both Earth and other planets is the perspective it has provided me on both. A foundation in Earth science helps one interpret observations of other planets, since much of the well‐explored physics of our own atmosphere can be applied to other planets. There are baroclinic eddies on Mars and Saturn, lightning storms due to water condensation on Jupiter and Saturn (and methane convective storms on Titan), and so on. But the relatively poorly observed planets of our Solar System and barely observed rocky exoplanets force us to ask basic, global questions and put our own planet in a larger context. In Earth science, we got caught up in the details so much a couple of decades ago that we largely stopped asking basic questions. In recent years, though, climate change has taught us that we do not understand Earth as well as we may have thought, and some scientists have begun once again to ask basic questions of our planet. These papers and others like them have effectively taken a planetary perspective on our own planet, to the betterment of our field. Exoplanet science has taken things a step further by placing the “small” number of planets in our solar system into the context of thousands of other planets. Given that large a sample, seemingly simple questions such as what determines whether a planet even has an atmosphere turn out to be much more fascinating than anticipated (e.g., Zahnle & Catling, 2017). Conversely, the history of habitability in our own solar system provides insights into processes that may be in play on exoplanets that we as yet know little about (Del Genio et al., 2019). This cross‐discipline fertilization is a trend I hope will continue.