Guidelines for naming a planet’s surface are biased towards men, academic claims as research finds just 2% of craters on Mars are named after women

An academic has said that guidelines for naming the planet’s surface features are not comprehensive enough and are biased towards men, with research showing that less than 2% of Mars’ craters are named after women.

Analysis of the International Astronomical Union (IAU) database also revealed that only 32 (2%) of the 1,578 known lunar craters are named after a woman.

Planetary features are distinct characteristics or elements found on or within a planet’s surface.

In addition to craters, it also includes mountains, valleys, canyons, volcanoes, oceans, deserts and many others.

In an open letter published in the journal Nature Astronomy, Annie Lennox, a doctoral researcher at the Open University, said the male-biased culture of naming planetary features is “inherently harmful to women and marginalized groups.”

It urges the International Astronomical Union — an international association of professional astronomers — to change its policies that are “biased toward cisgender white men.”

Ms Lennox, from Aberdeenshire, said: “Space exploration has revealed worlds of rock, ice and…metal.”

“For all worlds in our solar system, it has become commonplace to name prominent surface features such as craters.

“Distant craters on the Moon, Mars and Mercury record a history much closer to home: celebrating the achievements of humanity, and to a lesser extent the human race.”

Italian astronomer Giovanni Battista Riccioli first began naming lunar craters in 1635, Lennox said, and adopted the names of famous scientists for his discoveries — a tradition still followed at the International Astronomical Union today.

While the IAU does not award names itself, it helps establish working groups or task forces to propose and approve names for specific features based on certain guidelines – often honoring historical figures, myths, or cultural themes.

Ms Lennox said the IAU guidelines have an impact on the diversity and inclusiveness of the scientific communities that ultimately choose the names.

“Surface features are named according to conventions established and maintained by the IAU,” she said.

“It is frustrating that elements of current agreements crystallize historical injustices and contribute to a lack of diversity within labels.

“This is an example of how the systematic underrepresentation and undervaluation of women and marginalized groups appears in today’s scientific systems.”

Her research found that Mercury is slightly better than the Moon and Mars in female representation – with 49 out of 415 craters (11.8%) having feminine names.

Ms Lennox believes this is because Mercury is a more recently explored planet than some other planets in the solar system and may have benefited from the increase in the number of women working in STEM.

Mars is the worst, with only five of the 280 craters (1.8%) named after women.

Meanwhile, all the names of the craters on Venus have a female origin, but Ms Lennox said only 38% were “named after real women who have made real contributions to society”.

“On the only planet that purports to exclusively celebrate the contributions of women, more meaningless features, arbitrary female first names or names of mythical goddesses are given than those of real women,” she said.

“The crux of this argument is that valuing celebrity status—focusing on recognition and prioritizing fame over contribution—inherently disadvantages women and marginalized groups regardless of field.”

Ms Lennox said searching for the names of interplanetary craters was her starting point, but she now works with teams around the world to analyze every named feature in the solar system.

“I’ve named some of the potholes myself,” she said.

“I knew I wanted to name my discoveries after women because I felt women were rarely represented in the field I was studying, even though statistics on this are not readily available.

“That realization really drove this whole project.”