Requirements for becoming an astronaut

Which medical and psychological standards will be used to select the candidates?

An ESA Astronaut requires a multitude of skills, capabilities and characteristics. One important component of finding someone with the ‘right stuff’ is an assessment of how healthy each applicant is from a medical and psychological perspective. A general overview of the types of medical and psychological health criteria that will be used in assessing each candidate is given overpage.

In general, normal medical and psychological health standards will be used. These standards are derived from evidence-based medicine, verified from clinical studies.

• The applicant must be free from any disease.
• The applicant must be free from any dependency on drugs, alcohol or tobacco.
• The applicant must have the normal range of motion and functionality in all joints.
• The applicant must have visual acuity in both eyes of 100% (20/20) either uncorrected or corrected with lenses or contact lenses.
• The applicant must be free from any psychiatric disorders.
• The applicant must demonstrate cognitive, mental and personality capabilities to enable him/her to work efficiently in an intellectually and socially highly demanding environment

Do I need to be fit to become an astronaut? Which sport should I pursue?

It is important to be healthy, with an age-adequate fitness level. We are not looking for extreme fitness or top level athletes – too many over developed muscles may be a disadvantage for astronauts in weightlessness.

There is no specific sport that can be recommended. Physical activities are in general beneficial to your health.

How can I prepare for the medical tests?

During the medical selection, applicants will undergo numerous tests across many health areas. Some tests are physically demanding, like bicycle or treadmill exercises. Some may also be invasive and others may be just questionnaires. There is nothing you can do generally to prepare for these medical examinations. If an examination requires specific preparations, such as fasting before giving a blood sample, applicants will receive instructions.

Do astronauts develop serious health problems during their stays in space?

No, there are no dangerous conditions that develop because of spaceflight. However, the space environment is hazardous and the astronauts’ well-being depends on life-support systems. Weightlessness does have potentially temporary negative effects on human physiology, such as physical deconditioning and bone demineralisation. The ESA Crew Medical Support Office and its staff are responsible for avoiding such hazards and preventing the space environment from affecting the physical and mental health of the astronauts. The environment and life-support systems are closely monitored, and there is a thorough preventive and countermeasure programme.

Is it more difficult for a woman to become an astronaut?

No, from the physical point of view, it is not harder for a woman. The medical and psychological requirements for women and men are identical, apart from, of course, some gender-specific medical examinations.

Physical fitness and cardiovascular fitness are always evaluated on an individual basis and the fitness target values are adjusted to the physiological differences between men and women. A woman therefore does not have to meet the male norms, and vice-versa.

My vision is not perfect; can I still become an astronaut?

There is no clear yes/no answer because there is such a multitude of visual defects. However, vision problems account for most disqualifications. The main tests involve visual acuity, colour perception and 3-D vision.

Wearing spectacles or contact lenses is not a reason for disqualification per se, but it has to be evaluated if, for example, a visual defect is known to progress rapidly. This could mean disqualification. Minor visual defects, even though requiring lenses, may be regarded as compatible with space duties.

Recently, a variety of surgical interventions to correct visual acuity has become more common. Some of these procedures will lead to disqualification, while others are acceptable. Every case will be judged individually.