Spacecraft are engineered to withstand the load it endures during launch and other possible events that might occur on its mission, while carrying payload such as cargo or science instruments that cover its costs.
One example is the Psyche mission, which studies an asteroid believed to be left over from planet formation like Earth. Scientists hope it will shed more light on dark energy.
Unmanned Spacecrafts
Unmanned spacecraft are designed to carry out missions without human participation on board, typically at lower costs and risk than their manned counterparts.
At present, spacecraft include robotic spacecraft, unmanned resupply spacecraft and unmanned scientific/observational probes. Furthermore, certain habitable spacecraft such as Salyut 7 and Mir from ISS contain robotic features and capabilities with various levels of autonomy.
NASA has increasingly relied on unmanned probes for conducting its scientific work in space. Examples include Mars Pathfinder rover and Galileo spacecraft exploring Mars, while satellite observatories such as Hubble Space Telescope provide us with amazing pictures of distant heavenly bodies in the cosmos.
However, there’s no denying the public remains eager to witness astronauts in space – hence its inclusion as an integral component of NASA’s budget even during these financially constrained times. It will provide astronauts with transport back to the Moon as permanent residence and eventually take them on missions to other planets.
Robotic Spacecrafts
Space robots can perform many of the same functions that humans do, such as navigation and collecting data, but much faster, giving scientists access to more areas in less time.
Most space probes, like those sent to explore Mars by robotic rovers, are unmanned. Unlike Apollo lunar landings which involved human life support systems that required fueling on an ongoing basis and took up precious space, robotic probes do not incur such expenses.
These spacecraft are also better suited to long journeys, repetitive measurements and remote areas where humans cannot withstand extreme temperatures and radiation exposure. Furthermore, some planets cannot be reached using current crewed spaceflight technology.
Cargo or resupply spacecraft are typically robotic spacecraft used to deliver food and water supplies to the International Space Station, or replenish satellites already in orbit with fuel. Some may even provide emergency repairs on damaged satellites by docking with them to repair or service it directly.
Human Spacecrafts
Humans travel into space on board manned spacecraft that are launched from Earth and return after orbiting it, using high-energy density propellants for launch and dissipating energy as heat during reentry through Earth’s atmosphere. Space flight requires higher velocities than ground or air transport, causing greater forces on astronauts’ muscles; however, weightlessness reduces this sensation, aiding their maneuvering vehicles and conducting EVAs successfully.
Yuri Gagarin became the first human in space with his Vostok 1 rocket’s suborbital flight. Shortly afterwards, the United States began developing their own human spacecraft programs — eventually producing Mercury and Gemini vehicles.
Interstellar Spacecrafts
Voyagers made history when they left Earth’s orbit to venture beyond our solar system’s bubble of charged particles and enter space between stars 92 billion miles away from home and still sending data back home, decades after launch. Today they remain silent ambassadors of our planet’s past and future.
Recently, scientists at JHU-APL published a study outlining a proposed interstellar probe which would travel further and faster than Voyager to reach the edge of our solar system and explore space beyond. Their proposed mission would rely on next-generation plutonium-238 thermoelectric generators which can remain operational even thousands of miles from their Sun.
The probe would use gravity assist to speed towards various celestial bodies such as Jupiter or Uranus, siphoning off some of their speed as it passed by and using its increased velocity to reach outer edges of our solar system and enter its heliosheath.