Al Drago/The New York Times

Sen. Mark Kelly (D-Ariz.) and his wife, former Rep. Gabby Giffords, depart a swearing-in ceremony in December. Before reaching federal office, Kelly was best known as an astronaut.

February 9, 2021

Cornell Professor Reflects on Arizona Sen. Mark Kelly’s Contributions to Space Exploration

Print More

While COVID-19 took center stage last year, science continued to celebrate exceptional leaps in other areas of research. The lessons learned from trial and error even found themselves translated into politics. 

The bridge between science and government was showcased in December 2020 when Sen. Mark Kelly (D-Ariz.), a retired astronaut, was sworn in as Arizona’s newest senator in a special election.

Kelly’s experience as a scientist has informed his resilience and aptitude to make a bid for office, as he contributed to large bodies of research and logged over 50 days in space during his service to NASA from 2001 through 2011

“When you are orbiting the earth at 25 times the speed of sound and bad stuff starts to happen, you have to work the problem as a team,” Kelly said in his campaign announcement. “You can not dismiss ideas based on the politics of the person offering them.”

Two months before he was sworn into office, Kelly’s great contribution to space research was recognized by NASA as integral research since the founding of the International Space Station in 2000.

In 2014, Mark Kelly and his twin brother, Scott Kelly, who is also a retired astronaut, participated in NASA’s twin study to make observations on the changes the human body endures in microgravity. The study shed light on how scientists can better prepare the human body for extreme environments — as the pace of space exploration picks up steam. 

Weill Cornell Prof. Christopher E. Mason, physiology and biophysics, spearheaded the gene expression leg of the study that Kelly participated in. Mason worked simultaneously with nine other research teams, each focusing on a specific biological factor including circadian rhythm, mathematical modeling, cognition, exercise and changes in the genome.

“I have always had an interest in space and genetics,” Mason said. “[I’m interested in what] happens to the body in [microgravity].” 

Scott Kelly, Mark Kelly’s twin brother, headed into space in 2014 and lived at the International Space Station for one year, while Mark stayed on Earth. The two routinely sent biological samples.

Using the biological samples, Mason examined the gene changes in Scott’s DNA and RNA compared to Mark’s, as well as their microbiota — the sum of all the bacteria found on the Kellys in both biological samples.  

The results were surprising: Scott’s telomeres had grown longer, a shocking discovery since telomeres shorten with age, according to Mason.

“[Telomeres] are basically the caps at the end of the chromosomes which keep the DNA intact and maintain integrity,” Mason explained. “You can imagine a shoelace and you have little plastic ends in the bottom — it’s like that but for your DNA.”

Mason suspects that the elongation may be due not to the effects of space, but to Scott’s strict work schedule aboard the International Space Station.

“When they are in space, they actually have a well-balanced nutritious diet, they exercise every day and they are pretty regimented about getting sleep,” Mason said. “They ironically have a healthier lifestyle in some ways than on Earth.”  

To eliminate potential variability in the study, Mark was given the option to follow the same diet and exercise schedule on Earth as his brother in space. However, as Mason described in an interview with the Sun, Mark ultimately opted for “nachos and margaritas.”

The study also found that Scott’s immune system went on “high alert” while in space, likely due to stress on the body from the extraterrestrial environment. In the space station, he picked up new microbiota.

When Scott Kelly returned to Earth, his cognitive function — measured by the speed at which he could solve problems — was also slightly lower than before his expedition.

Mason counted thousands of genes that had changed expression while in space, and about 91 percent of them reverted to their state before the trip after landing on Earth, the study found. 

Overall, the study reinforced that the human body — with the aid of gene editing — could be robust enough to survive longer missions in space.

“Most things about the body are very plastic and reform back to baseline,” Mason said. “We [now] know the beginning roadmap of what we would do to protect the genome or protect astronauts, especially if they are going somewhere on a one-way trip where there’s more radiation or environmental stressors.”