Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is currently carried out mainly by astronomers with telescopes, its physical exploration is conducted both by uncrewed robotic space probes and human spaceflight. Space exploration, like its classical form astronomy, is one of the main sources for space science.
Sally Kristen Ride was an American astronaut and physicist. Born in Los Angeles, she joined NASA in 1978, and in 1983 became the first American woman and the third woman to fly in space, after cosmonauts Valentina Tereshkova in 1963 and Svetlana Savitskaya in 1982. She was the youngest American astronaut to have flown in space, having done so at the age of 32.
Donald Edward Williams was an American naval officer and aviator, test pilot, mechanical engineer and NASA astronaut. He logged a total of 287 hours and 35 minutes in space.
John Mace Grunsfeld is an American physicist and a former NASA astronaut. He is a veteran of five Space Shuttle flights and has served as NASA Chief Scientist. His academic background includes research in high energy astrophysics, cosmic ray physics and the emerging field of exoplanet studies with specific interest in future astronomical instrumentation. After retiring from NASA in 2009, he served as the deputy director of the Space Telescope Science Institute in Baltimore, Maryland. In January 2012, he returned to NASA and served as associate administrator of NASA's Science Mission Directorate (SMD). Grunsfeld announced his retirement from NASA in April 2016.
The effects of spaceflight on the human body are complex and largely harmful over both short and long term. Significant adverse effects of long-term weightlessness include muscle atrophy and deterioration of the skeleton. Other significant effects include a slowing of cardiovascular system functions, decreased production of red blood cells, balance disorders, eyesight disorders and changes in the immune system. Additional symptoms include fluid redistribution, loss of body mass, nasal congestion, sleep disturbance, and excess flatulence. Overall, NASA refers to the various deleterious effects of spaceflight on the human body by the acronym RIDGE.
Colonization or settlement of Mars is the theoretical migration of humans to Mars and the establishment of long-term human presence on the planet. The prospect has garnered interest from public space agencies and private corporations and has been extensively explored in science fiction writing, film, and art. Organizations have proposed plans for a human mission to Mars, the first step towards any colonization effort, but thus far no person has set foot on the planet, and there have been no return missions. However, landers and rovers have successfully explored the planetary surface and delivered information about conditions on the ground.
Brian Todd O'Leary was an American scientist, author, and NASA astronaut candidate. He was part of NASA Astronaut Group 6, a group of scientist-astronauts chosen with the intention of training for the Apollo Applications Program.
Space medicine is an area in aerospace medicine that focuses on the medical care of astronauts and spaceflight participants. The spaceflight environment poses many unique stressors to the human body, including G forces, microgravity, unusual atmospheres such as low pressure or high carbon dioxide, and space radiation. Space medicine applies space physiology, preventive medicine, primary care, emergency medicine, acute care medicine, austere medicine, public health, and toxicology to prevent and treat medical problems in space. This expertise is additionally used to inform vehicle systems design to minimize the risk to human health and performance while meeting mission objectives.
Thomas Henry Marshburn is an American physician and a former NASA astronaut. He is a veteran of three spaceflights to the International Space Station and holds the record for the oldest person to perform a spacewalk at 61 years old.
The idea of sending humans to Mars has been the subject of aerospace engineering and scientific studies since the late 1940s as part of the broader exploration of Mars. Long-term proposals have included sending settlers and terraforming the planet. Proposals for human missions to Mars have come from agencies such as NASA, CNSA, the European Space Agency, Boeing, and SpaceX. Currently, only robotic landers and rovers have been on Mars. The farthest humans have been beyond Earth is the Moon, under the NASA's Apollo program.
Health threats from cosmic rays are the dangers posed by cosmic rays to astronauts on interplanetary missions or any missions that venture through the Van-Allen Belts or outside the Earth's magnetosphere. They are one of the greatest barriers standing in the way of plans for interplanetary travel by crewed spacecraft, but space radiation health risks also occur for missions in low Earth orbit such as the International Space Station (ISS).
Serena Maria Auñón-Chancellor is an American physician, engineer, and NASA astronaut. She visited the ISS as a flight engineer for Expedition 56/57 on the International Space Station.
Kathleen Hallisey "Kate" Rubins is an American microbiologist and NASA astronaut. She became the 60th woman to fly in space when she launched on a Russian Soyuz spacecraft to the International Space Station (ISS) on July 7, 2016. She returned to Earth in Kazakhstan on October 30, 2016, aboard a Soyuz. She was a crew member of Expedition 48/49 and Expedition 63/64 of the ISS. Rubins has spent a total of 300 days, 1 hour, and 31 minutes in space which is the fourth most days in space by a U.S female astronaut.
Astronauts are exposed to approximately 72 millisieverts (mSv) while on six-month-duration missions to the International Space Station (ISS). Longer 3-year missions to Mars, however, have the potential to expose astronauts to radiation in excess of 1,000 mSv. Without the protection provided by Earth's magnetic field, the rate of exposure is dramatically increased. The risk of cancer caused by ionizing radiation is well documented at radiation doses beginning at 100 mSv and above.
Women have flown and worked in outer space since almost the beginning of human spaceflight. A considerable number of women from a range of countries have worked in space, though overall women are still significantly less often chosen to go to space than men, and by June, 2020 constitute only 12% of all astronauts who have been to space. Yet, the proportion of women among space travelers is increasing substantially over time.
NASA Astronaut Group 23 was announced on December 6, 2021, with the class reporting for duty some time in 2022. Twelve astronaut candidates were selected, including seven men and five women.
Julianne Pollard-Larkin is an American medical physicist, assistant professor at MD Anderson Cancer Center in Houston, TX and is also the interim Physics Service Chief for the Thoracic service of MD Anderson’s Division of Radiation Oncology. She is also the Vice-Chair of the American Association of Physicists in Medicine (AAPM) Diversity and Inclusion Subcommittee.
Anil Menon is a lieutenant colonel in the United States Air Force, emergency medicine physician and NASA astronaut.
Andre Douglas is an American systems engineer and NASA astronaut candidate.
