Space Exploration Missions
In 2010, youth worldwide shared their visions of the future of human space flight and told us that satisfying inherent human curiosity is one of the major reasons why it is important. Indeed, because of this basic need, we have been exploring space in wonder, while gazing from Earth, since the dawn of humankind.
More recently, over the past five decades, we have successfully launched spacecraft into space. Within our solar system, robotic missions have surveyed the sun, planets, and moons near and far, while other missions have sought out knowledge about asteroids and comets. During the Apollo space flight program, we visited our moon, allowing for humans to actually step out onto the lunar surface and explore it firsthand. Since then, robotic missions have landed rovers directly on Mars so that we can study its surface and atmosphere remotely. At the same time, Mir, Shuttle, and the International Space Station (ISS) have focused on learning how humans can live and work in space, gaining essential data about how low gravity and living outside of Earth’s protective atmosphere affect the human body. Whether researching directly with people on crewed space missions or remotely with robotic spacecraft, these types of investigations all require the work of 1000’s of people and are important aspects of successful human space exploration. More future research of both types will enhance our knowledge of the solar system and enable us to live on other planets.
The universe is huge though, and our questions are numerous. Our sun is only one of about 200-400 billion stars in the Milky Way galaxy and the Milky Way is only one of 100’s of billions of galaxies in the visible universe. Just recently, two robotic spacecraft, Voyagers 1 and 2, have begun to explore beyond the edge of our solar system and into interstellar space. Closer to home, the Hubble Space Telescope, positioned in orbit above the Earth’s atmosphere, has been transmitting images of distant objects in the universe for more than a decade. Its images have revolutionized our thinking about the age of the universe and revealed forces that we have never encountered before and still do not fully understand, such as dark energy and dark matter. In a few years, a new more powerful telescope will be launched deeper into space that will allow us to view even older and more distant stars and galaxies.
Space exploration opportunities are growing. To date, only a few government space agencies have carried out missions, but many additional countries are now becoming more actively involved in space exploration, developing their own independent space programs and partnering with other space agencies for joint activities. Over the past decade or so, private space companies have been emerging to take a prominent role in space travel systems and exploration. Their growing participation is further indication of how space exploration is diversifying, increasing the potential for an influx of new ideas and for more people, even students, to engage directly in space science and to one day possibly travel to space.
Space Science and Technology
Past and current missions and those yet only in the dream stage require human imagination, ingenuity, and persistence to create the technology and design the experiments that enable progress in space exploration. Key space technologies are both large and small, spanning from vehicles to carry and protect equipment, robots, and humans to nanotechnology and pharmaceuticals. Robotic spacecraft, landers, and rovers, for instance, can be designed to tolerate heat, cold, vacuum, and radiation that would kill a human crew. These robots can collect a great deal of information during a mission by using scientific instruments that “sense” their surroundings much the same way that human explorers use their senses--sight, hearing, smell, and so on — to learn about the places they discover. These instruments commonly include cameras (to take pictures of planetary surfaces and atmospheres), spectrometers (to precisely measure the color or wavelength of light to tell from a distance what elements, chemicals, and minerals make up its atmosphere and surface), and electromagnetic wave detectors (to map a planet's outer atmosphere and magnetic field).
Since human explorers have the best ability to adapt to the unexpected (especially when things go wrong!), to prioritize amongst choices during complex experiments and constructions, and to possess the passion and drive for discovery, we have also devised technological tools that assist our in-person experimentation. Onboard the ISS, for example, astronauts and cosmonauts use tools such as growth chambers, centrifuges, microscopes, imagers, and detectors to carry out experiments. Other advanced technology includes space suits, robotic assistants, and telecommunications. Collectively, research carried out by robots and humans allows us to expand our knowledge about the space environment, basic principles about the nature of matter unperturbed by the Earth’s gravitational field, and the impact of space on the human body and other living things. The more we explore, however, the more we realize what we do not know, but as technology and research advance, so does human understanding and our capability to do further space science and exploration.
The human body changes in space, and crewed space flight offers opportunities to scientifically examine these changes and create technologies that can act as countermeasures to their effects. Exposure to space conditions alters the sensory-motor and cardiovascular systems and can weaken the musculoskeletal and immune systems. Stress associated with being far from Earth, altered biological rhythms, busy schedules, confined conditions, and the small number of people one interacts with day after day in space can lead to errors and changes in a person’s behavior. Many countermeasures to help minimize these problems already exist onboard a space craft, such as medical equipment, vehicle anti-radiation shielding, life support systems, exercise equipment, and careful daily scheduling. More scientific research and countermeasure technology is needed, however, in order to allow humans to travel deeper into the solar system and beyond.
We can use technology and scientific methods to learn a lot about space without ever leaving Earth. For instance, we can study objects in space using ordinary light and radio wave telescopes or Earth-based radars. We can study meteorites--rocks that fell to Earth from space — in much more detail on Earth than onboard a spacecraft. Drop towers and airplanes that climb and dive on steep roller-coaster paths can provide opportunities to study weightlessness. Important space environment experimental analogs also exist on Earth, such as extreme or remote locations at the bottom of the ocean, near the South Pole, and in the middle of the hot dry desert, and research facilities with specialized equipment.
With the aid of technology, humans have remotely and directly begun exploring the solar system and beyond. Through scientific experimentation, we are beginning to answer the many questions about space that have captivated our imaginations for thousands of years. In 2012, we asked youth worldwide to share their vision and tell us about the future: “How will humans use science and technology to explore space, and what mysteries will we uncover?”
History of Human Exploration