Headlines about NASA’s Twins Study Stir Public Confusion

Category: Science/Environment


Unlocking Word Meanings

Read the following words/expressions found in today’s article.

  1. aboard / əˈbɔrd / (adv) – carried on a transportation vehicle

    The astronauts were aboard the International Space Stations for six months.

  2. headline / ˈhɛdˌlaɪn / (v) – to put a title in a report or article

    News websites headlined their articles with details of the shuttle launch.

  3. rebut / rɪˈbʌt / (v) – to disprove something or to present arguments

    The scientist planned to rebut what the journalist said through an interview.

  4. isolation / ˌaɪ səˈleɪ ʃən / (n) – the state or condition of being alone and separated from others

    He was the only astronaut in the International Space Station. His isolation made him sad.

  5. hostile / ˈhɒs tl / (adj) – unpleasant or unfriendly

    Mercury’s environment is so hostile; many believe it cannot sustain any life form.


Read the text below.

Several news sites have incorrectly reported that astronaut Scott Kelly is no longer identical to his twin brother.

Retired astronauts Scott and Mark Kelly are NASA’s first and only identical twins who are part of the agency’s Twins Study program. With this project, NASA aims to get insights on the changes that happen to people who travel to space and those who remain earthbound.

For the Twins Study, Scott went aboard the International Space Station for 340 days, which is much longer than the usual six-month mission. After the mission, NASA compared the twins in several aspects.

When Scott came back, some news sites incorrectly headlined their reports saying that the twins were no longer identical. Some even cited a 7% change in Scott’s DNA. However, some experts rebutted, saying that Scott’s DNA did not change by 7%. If it had changed just by over 2%, Scott would be more different from another human being than a chimpanzee.

Experts said that the news sites mistook DNA—how genes are arranged—with gene expression, which is how genes function within the cell. In the Kellys’ case, Scott’s immune system became hyperactive compared to Mark’s because of the former’s exposure to space.

NASA plans to use studies on prolonged spaceflight, including Scott’s 340-day mission, to determine the effects of five factors—space radiation, isolation, distance from Earth, gravitational conditions, and hostile environments—on humans. The agency is compiling the data in preparation for a possible mission to Mars, which would take about three years.

Viewpoint Discussion

Enjoy a discussion with your tutor.

Discussion A

• If extended missions to space were proven to cause major changes in astronauts, should future missions still proceed? Explain.
• Would you be willing to risk your own health for a study or cause that you believe in? Why or why not?

Discussion B

• How do you think astronauts build physical and mental strength to cope with the conditions in space? Discuss.
• Which of the five factors mentioned (space radiation, isolation, distance from Earth, gravitational conditions, hostile environments) would be most difficult for astronauts to handle? Why?