Flyby Spacecraft
Flyby spacecraft pass planets or moons only once, using onboard instruments to capture images and measure magnetic fields, atmospheres, and particle environments during a brief encounter. They do not slow down or go into orbit but continue onward along their flight path.

Examples include Voyager 1 and Voyager 2, which collected data from Jupiter, Saturn, Uranus, and Neptune before heading toward interstellar space. China’s Tianwen‑2 will also perform a flyby of a main-belt comet after collecting samples from a near‑Earth asteroid, combining exploration and sample-return goals.

​Orbiter Spacecraft
Orbiters slow down near their targets so they can be captured by gravity and circle a body many times. From orbit, they can build detailed maps, monitor changes over time, and act as relay stations for other spacecraft. Engineers must ensure that orbiters can function through periods of occultation, when the planet blocks sunlight or radio contact.
Examples:

• Lunar orbiters such as 嫦娥一号 and 嫦娥二号 mapped the Moon’s topography and surface features for later landing missions.​
• 天问一号 serves as a Mars orbiter, imaging the surface and supporting communications with the 祝融 rover.​
• Earth‑observation orbiters include 高分五号 and 高分十四号, which provide hyperspectral and high‑resolution imaging of land and atmosphere.​
• 风云三号E (polar‑orbit) and 风云四号 (geostationary) are meteorological satellites measuring clouds, temperature, and humidity for weather forecasting.​
• 大气环境监测卫星, 陆地观测卫星, 海洋二号C, and 委内瑞拉遥感卫星 are Earth‑observation and environmental satellites used to monitor air quality, land resources, ocean conditions, and regional imaging needs.​
• 东方红一号 and 东方红五号 platforms support communication, broadcasting, and observation payloads in Earth orbit, illustrating the evolution of Chinese satellite buses.

Space Observatory Spacecraft
Space observatories operate in Earth orbit or special solar orbits to study stars, galaxies, black holes, and exoplanets. Observing from space avoids atmospheric distortion and allows measurements in wavelengths blocked at the surface, such as some ultraviolet and infrared bands.
Examples:

• The Hubble Space Telescope observes mainly in visible and ultraviolet light from low Earth orbit.
• The James Webb Space Telescope (JWST) orbits around the second Lagrange point (L₂), about 1.5 million km from Earth, using a 6.5 m segmented mirror and a large sunshield for infrared astronomy.
• China’s 悟空号 (DAMPE) studies high‑energy cosmic rays and gamma rays, and 墨子号量子卫星 (Mozi/QUESS) tests quantum communication and entanglement experiments from low Earth orbit.
• China’s Xuntian (巡天) Space Telescope, which will share an orbit with the Tiangong space station, is designed to conduct wide‑field galaxy surveys and allow in‑orbit maintenance.
  

Communication and Navigation Spacecraft
Some spacecraft are developed to support exploration and operations rather than directly study celestial bodies. Communication spacecraft act as relays, transferring data between distant spacecraft and Earth, especially when surface transmitters have limited power.

For example, Mars Odyssey relays data from Mars rovers back to Earth.
Other orbiting spacecraft, like navigation satellites, provide position and timing signals. Systems such as the Global Positioning System (GPS) and BeiDou Navigation Satellite System (北斗卫星导航系统) make precise navigation possible on Earth and support spacecraft trajectory determination in deep space missions.

Rover Spacecraft
Rovers are mobile robots capable of moving across a planet’s surface. They carry navigation cameras, spectrometers, and robotic arms to collect and analyze samples. Mobility allows them to explore varied terrains and compare geological features.
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NASA’s Perseverance rover records rock samples in sealed tubes on Mars, while China’s Zhurong (祝融) rover investigates Martian soil and sand dunes. Both provide data that complement orbiter observations.

Penetrator Spacecraft
​Penetrators are built to impact a surface at high velocity and embed scientific instruments beneath the upper layer. This design allows them to study subsurface materials that cannot be reached by landers or observed from orbit.
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The Deep Impact mission used such a device to strike Comet Tempel 1 and analyze its internal composition. Future concepts may use penetrators to study icy moons, searching for signs of water or buried organic materials.