Meteorology and Mercury: Learning about a Rare Astronomical Event

In El Paso, a team of humanists (led by The Humanities Collaborative at EPCC-UTEP's Faculty Research Associate, Dr. Andrew Fleck) and scientists collaborated to raise awareness of and interest in the transit that would occur. Although weather thwarted some aspects of our efforts, the occasion of the transit of Mercury allowed for the team to generate public interest in the cooperative study of the science of astronomy and the humanistic interest in the history of science.


A November 11, 2019 tweet from the account @earthskyscience shows a photograph of Mercury just after it crossed into the disk of the sun.

Scanning the Skies

In Europe through the seventeenth century, some things that we would today associate with the study of distant astronomical bodies were classified as part of the weather. Today’s weather forecasters are still called “meteorologists,” even though they do not usually report on meteors, comets, or extraterrestrial material. Into the seventeenth century, however, the powerful theories of Aristotle exerted enough influence that some of the phenomena that might seem to us to be obviously part of the discipline of astronomy were actually associated with a different territory in science. Today we understand that meteors are stony debris floating in the vacuum of space that may pass through the earth’s atmosphere and that comets are balls of dust, rock, and frozen gases orbiting stars like our sun at high velocity and leaving tails in their wake that are illuminated by the light of the star. Early modern Europeans understood meteors and comets to be debris exhaled by the Earth that ignited as they moved through our sky. In a sense, everything that happened more than a few feet above the ground, from clouds and rain through the distant stars of the constellations, participated in a unified realm of meteorology.

Leading up to the transit, much was made of Pierre Gassendi’s observation of the first transit of Mercury on 7 November 1631. Gassendi had learned that Johannes Kepler’s calculations suggested that Mercury would pass between Earth and the Sun and that human observers would be able to witness this orbit. Gassendi, and others, set up telescopes in order to describe the transit, but the weather in Europe did not cooperate and it was very cloudy at the time of the transit. Gassendi was fortunate that the clouds finally parted above his simple observatory that morning and he was able to trace the planet’s path across the disc of the Sun. Other observers were not as fortunate, so Gassendi’s account of the transit was the only one available to most readers in 1631-2. For us in El Paso, the unusual cloudiness of the day frustrated our ability to witness the transit through the telescopes Dr. Olienka De la O Fernandez had set up at the Valle Verde campus of El Paso Community College and that Dr. Hector Noriega-Mendoza set up at The University of Texas-El Paso. Instead, the many interested members of the community who hoped to see the transit had to be satisfied with the live-stream available through a variety of observatories broadcasting that morning. One of the best of these was that offered by Griffith Park Observatory in Los Angeles. A set of highlights from NASA’s Solar Dynamics Observatory were posted for the public.

Spreading the Word

The crowds that gathered at EPCC and UTEP to observe the transit became interested in the event in part through the extensive publicity generated in the weeks leading up to the event. Dr. Fleck arranged for a friend and colleague, Dr. Renee Weber of NASA’s Marshall Space Flight Center, to participate in several dialogues about the upcoming transit. Together they appeared on a radio program called Science Studio, hosted by Dr. Keith Pannell on the local NPR affiliate, KTEP. During that half-hour broadcast, Dr. Fleck and Dr. Weber talked about their broader interests in astronomy, including a long discussion of comets in English literature, and about the fascinating physics of the sun, before turning their attention to the science of the transit of Mercury. Observing such a transit offers on a much closer scale the same kinds of science behind the search for and study of “exoplanets,” those planets orbiting distant stars outside of our solar system. Dr. Fleck also appeared on his own in a conversation with Louie Saenz on KTEP’s Focus on Campus in order to generate awareness about the upcoming transit and a program that he and Dr. Weber would be presenting on the UTEP campus on the Monday prior to the transit.

On Monday, November 4, 2019, Dr. Fleck interviewed Dr. Weber via a video conference call in the UTEP Library's high-tech “Collaborative Lab.”


On November 4, 209, Dr. Fleck and Dr. Weber discuss the upcoming transit of Mercury.

The event, covered by two local television news stations (KDBC and KFOX), attracted a sizeable crowd. Fleck and Weber talked about the mechanics of the transit, about recent research on Mercury and the Sun, about the history of the transit of Mercury, and about the search for planets outside of our solar system over the last few decades. The audience learned about the reasons that make the transit of Mercury (and the similar phenomenon of transits of Venus) so rare and about the likelihood that most stars have planets of some variety in orbit around them. Together, Fleck and Weber also discussed such issues as the relationship between curiosity, research, and application – the fact that an early modern astronomer’s quest to create a network of observers watching transits in order to create an accurate measure of the distance between Earth and the Sun led to additional terrestrial exploration – and the philosophical implications for humans as they came to terms first with the fact that the cosmos does not revolve around us and then with the fact that our solar system is not the only one with potentially-habitable planets orbiting its star. These exciting conversations demonstrated that productive dialogue between STEM fields and humanists can reach a public audience.


November 11, 2019 was unfortunately a cloudy morning on the Valle Verde campus of El Paso Community College.


On November 11, 2019, Dr. Hector Noriega snaps a picture of the youngest observer hoping to see the transit of Mercury as Dr. Fleck steadies the telescope.

Finally, the day of the transit arrived on November 11. It was a very cloudy morning, but everyone involved in the events across the UTEP and EPCC campuses were optimistic that the clouds might just clear and the sun would shine brightly enough to make the shadow of Mercury visible through a telescope. Although that hope was frustrated, the public that showed up in two locations to ask about the transit and to hope that they might get a glimpse of speedy Mercury passing in front of the sun gave all of us hope that collaboration – across the disciplines of the humanities, across the fields of the university, across the boundaries of institutions, and across the public – might help us make the world go ’round in company with other curious human beings. 

Written by Dr. Andrew Fleck, The University of Texas at El Paso
Faculty Fellow, The Humanities Collaborative at EPCC-UTEP