Mars, as seen by the webcam on European Space Agency’s Mars Express orbiter in 2016. (Ho/Agence France-Presse via Getty Images/European Space Agency)

As an astrophysicist, I must caution against premature optimism from the experiments of the International Potato Center as described in the April 4 Health & Science article “A ‘Unique’ potato that can grow in a Mars-like climate.”

The study cannot and does not fully mimic the conditions on Mars that would hamper the growth of potatoes and other food. We cannot effectively replicate on Earth the absence of a strong magnetic field on Mars, the continuous unshielded exposure to cosmic rays, and the impact of Mars’s low gravity (one-third of Earth’s). Plants also would be challenged by the toxic soil of Mars, the average temperature of minus-75 degrees Fahrenheit (which can go as low as minus-184 degrees), the absence of liquid water on the planet’s surface, etc. How accurately did the simulated atmosphere represent the gas ratios on Mars of 96 percent carbon dioxide, 2 percent argon, 1.9 percent nitrogen and 0.1 percent oxygen? Or the air pressure, which is 6 percent of Earth’s? How closely did artificial lighting approximate Martian sunlight and its composition?

This research may help us expand farming on Earth, but the researchers have a long way to go, literally, to farm on Mars.

Epaminondas G. Stassinopoulos, Potomac